Week 5 - Cardiology Flashcards
What is the 1st line investigation for patients with chest pain, palpitations or blackouts?
ECG
For what 2 conditions is an ECG life-saving?
- Arrhythmias
2 Acute Myocardial Infarction
What are 2 ways to determine the heart rate in an ECG?
- 300 divided by the number of large squares between each QRS complex
- Number of QRS complexes across ECG (10sec) x6
What is the normal range for an ECG PR interval?
- <1 large square
- <200ms
What is the normal range for an ECG QRS interval?
- <3 small squares
- <120ms
What is the normal range for an ECG QT interval?
- <11 small squares
- <440ms
What are the 5 questions to determine an ECG rhythm?
- What is the QRS rate?
- Are the QRS complexes regular?
- Is the QRS broad or narrow?
- Are there P waves?
- What is the P:QRS relation?
Describe normal sinus rhythm?
- Normal QRS rate
- Regular QRS complexes
- Narrow QRS complex
- P waves present
- 1:1 P:QRS relation
Describe complete AV block?
- Slow QRS rate
- Regular QRS complexes
- Can be broad or narrow QRS
- P waves present
- No P:QRS relation
Describe Second degree AV block?
- Normal/Slow QRS rate
- Irregular QRS complexes
- Narrow QRS
- P waves present
- 1:1 or 2:1 P:QRS relation
What is left axis deviation in an ECG?
-30 to -90 degrees (predominantly negative QRS in II and aVF)
Describe the normal morphology of the P, QRS & T wave?
- P wave is positive in the inferior leads
- ST segment is flat
- T wave has the same polarity as the QRS
What leads would show ST elevation in an anterior ST elevation in acute coronary occlusion?
V1-4
What leads would show ST elevation in a lateral ST elevation in acute coronary occlusion?
- Lead I
- aVL
- V5&6
What leads would show ST elevation in an inferior ST elevation in acute coronary occlusion?
- Lead II
- Lead III
- aVF
What 2 things are needed to show ST elevation MI?
- Does the patient have signs of MI
2. Reciprocal ST depression in the opposite leads of ST elevation
Describe Pericarditis on the ECG?
- No reciprocal ST depression
- ST elevation across all the leads so not fitting a coronary distribution!
Describe a supraventricular tachycardia?
- Fast QRS rate
- Regular QRS complex
- Narrow QRS
- Can’t tell if there are P waves due to QRS going to quickly
- No idea about the P:QRS relation
Describe regular broad complex tachycardia?
- Fast QRS rate
- Regular QRS complexes
- Broad QRS
- No idea if there are P waves
- No idea about P:QRS relation
What is the gold standard for EBM?
RCT
What are guidelines evidence A?
Data derived from multiple randomised clinical trials or meta-analyses
What are guidelines evidence B?
Data derived from a single randomised clinical trial or large non-randomised studies
What are guidelines evidence C?
Consensus of opinion of the experts &/or small studies, retrospective studies, registries
What is a clinical trial?
Evaluation of a new therapeutic intervention (drug, device, procedure/surgery) in human volunteers
What must human volunteers be in clinical trials?
Healthy or patients with a disease
What is the clinical trial designed to be?
Unbiased, accurate, estimate of the effect of treatment
What are 4 questions to ask when interpreting a clinical trial introduction?
- What are they doing?
- Does it make sense?
- Is it an important problem?
- Does it relate to my patients?
What is the most important section in a clinical trial?
Methods
What are the 4 questions to ask when interpreting the clinical trial methods?
1. Who did the study?- academics, industry (degree of involvement) 2. Who was included? 3. Who was excluded? 4. Do they represent real life patients?
What are the 3 questions to ask when interpreting the clinical trial inclusion/exclusion criteria?
- What were the inclusion criteria?
- What were the exclusion criteria?
- Are the reasons for exclusion clear?- Intervention not thought to work in some, Safety
What are the 5 types of clinical trials?
- Randomized double blind placebo controlled trial
- Cluster randomized trial
- Factorial trial
- Cross over trial
- Adaptive trial design
What are 4 types of comparators?
- Placebo
- Active
- Factorial
- Blinding
What are the 4 outcomes of clinical trials?
- Hard endpoints- death, MI
- Soft endpoints- QoL
- Surrogates- decline in renal function
- Safety- angioedema
Describe the statistical analysis of clinical trials?
- Should be specified a priori
- Changes should be clearly documented with good
reason - Appropriate power calculation
- Interim analysis- was the trial stopped early?
What are the 4 factors to statistical analysis specified priori?
- Primary analysis
- Secondary analysis
- Subgroups
- Intention to treat
What is the formula to clinical trials results?
- Describe the population
- Effect on outcomes
- Subgroups
- Safety
Describe the CONSORT flow diagram & what it includes?
- Accounts for every patient
- Withdrawals
- Protocol violations
- Loss to follow up
- Exclusions
- Final number randomised and analysed
What are the 3 population questions to ask to check for bias in a clinical trial?
- Do they look like the patients they said they would enrol?
- Do they look like my patients?- characteristics, background therapy
- Are the groups balanced?
What are the 5 questions to ask regarding clinical trials effect size?
- What is the effect size?
- Is it clinically meaningful?- NNT
- Is it statistically robust?- P value, 95% confidence interval
- Is it consistent for different endpoints especially
the components of a primary composite? - Is it consistent across subgroups?- Internal validity
Describe the composites of clinical trials?
- Equal numbers of the two components
- Same direction and size of effect in both components of the composite
What are the 4 questions to ask regarding clinical trials discussion?
- Does the interpretation reflect the data?
- Is it a fair reflection?
- Does it frame it in the context of the wider literature?
- Are there any glaring omissions?
What are the 4 main factors interpreting a clinical trial?
- Take each section in turn
- Pay particular attention to the methods- Bias
- Are the results clinically meaningful and
robust?- Efficacy and safety - Do they apply to the patients that you see?
What is the definition of Heart Failure?
Failure of the heart to pump blood (=oxygen) at a rate sufficient to meet the metabolic requirements of the tissues
What is heart failure caused by?
Abnormality of any aspect of cardiac function & with adequate cardiac filling pressure.
What is heart failure characterised by?
Typical haemodynamic changes (e.g. systemic vasoconstriction) & neurohumoral activation
What does heart failure cause clinically?
Breathlessness, effort intolerance, fluid retention & is associated with frequent hospital admission & poor survival
Describe the disabling effects of heart failure?
- Associated with a worse quality of life than almost any other medical condition
- Because of symptoms (dyspnoea, fatigue) & frequent deterioration leading to hospital admission
What is the chance of deadly outcomes in heart failure?
- Worse survival than most forms of cancer
- 50% mortality within 5 years
List the 5 common (in UK) causes of heart failure?
- Coronary artery disease (MI)
- Hypertension
- “Idiopathic” (i.e. unknown)
- Toxins (alcohol, chemotherapy)
- Genetic?
List the 6 less common (in UK) causes of heart failure?
- Valve disease
- Infections (virus, Chaga’s)
- Congenital heart disease
- Metabolic (e.g. haemochromatosis, amyloid, thyroid disease)
- Pericardial disease (e.g. TB)
- Endocardial disease
List the 4 main types of heart failure?
- HF-REF (“systolic HF”)
- HF-PEF (“diastolic HF”)
- Chronic (“congestive”)
- Acute (“decompensated”)
Describe HF-REF (“systolic HF”)?
- Reduce ejection fraction
- Younger
- More often male
- Coronary aetiology
Describe HF-PEF (“diastolic HF”)?
- Preserved ejection fraction
- Older
- More often female
- Hypertensive aetiology
Describe Chronic (“congestive”)?
- Present for a period of time
- May have been acute or may become acute
Describe Acute (“decompensated”)?
- Usually admitted to hospital
- Worsening of chronic
- New onset (“de novo”)
List the pathophysiology result of myocardial injury?
Left ventricular systolic dysfunction –> Perceived reduction in circulating volume & pressure –> Neurohumoral activation –> Systemic vasoconstriction. Renal sodium & water retention
List the 4 neurohumoral activations during myocardial injury?
- Sympathetic nervous system
- RAAS
- ET, AVP etc
- Natriuretic peptides
List 3 symptoms of heart failure?
- Dyspnoea (orthopnoea, PND) & cough
- Ankle swelling (also legs/abdomen)
- Fatigue/tiredness
List 6 signs of heart failure?
- Peripheral oedema (ankles, legs, sacrum, abdomen)
- Elevated JVP
- Third heart sound
- Displaced apex beat (cardiomegaly)
- Pulmonary oedema (lung crackles)
- Pleural effusion
What classification system is used in heart failure diagnosis?
New York Heart Association Functional Classification (class 1-4)
Describe Class 1 heart failure according to the New York Heart Association Functional Classification?
No symptoms & no limitation in ordinary physical activity, e.g. shortness of breath when walking, climbing stairs etc.
Describe Class 2 heart failure according to the New York Heart Association Functional Classification?
Mild symptoms (mild shortness of breath &/or angina) & slight limitation during ordinary activity
Describe Class 3 heart failure according to the New York Heart Association Functional Classification?
- Marked limitation in activity due to symptoms, even during less-than-ordinary activity, e.g. walking short distances (20–100 m)
- Comfortable only at rest
Describe Class 4 heart failure according to the New York Heart Association Functional Classification?
- Severe limitations
- Experiences symptoms even while at rest
- Mostly bedbound patients
List the 6 investigations that you would do in all patients with suspected heart failure?
- ECG
- CXR (exclude lung pathology, pulmonary oedema)
- Echocardiogram (chamber size, systolic & diastolic function, valves), CMR alternative
- Blood chemistry (U&Es, Cr, urea, LFTs, urate)
- Haematology (Hb, RDW)
- Natriuretic peptides (BNP, NT-proBNP)
What are the 4 stages to diagnosing heart failure?
- Signs & symptoms
- Examination
- Natriuretic peptides
- Echocardiography
What are the 5 investigations that you would do for selected heart failure patients?
- Coronary angiography
- Exercise test
- Ambulatory ECG monitoring
- Myocardial biopsy
- Genetic testing
Describe the SIGN guidelines for heart failure treatment?
- Beta blocker & ACE inhibitor
- MRA added to ACE inhibitor or ARB
- Sacubitril/Valsartan, stop ACE inhibitors & ARBS, continue beta blocker & MRA
- ICD or CRT-P/CRT-D, Ivabradine if sinus rhythm heart rate is >75bpm
- Digoxin, Hydralazine/isosorbide denigrate if intolerant to ACE inhibitor, ARB or Sacubitril/Valsartan due to renal dysfunction, hyperkalaemia or other side effects
- Referral to National Transplant Unit (LVAD/cardiac transplantation)
What are 2 conditions that you would use diuretics?
- Pulmonary oedema
2. Peripheral oedema
What is an ARB an alternative to?
Patients intolerant of an ACE inhibitor due to cough
What are the most evidence-based therapies in heart failure?
Beta-blockers
What does LCZ696 (Sacubitril/Valsartan) do?
- Angiotensin Receptor Neprilysin Inhibition (ARNI)
- Blocks Neprilysin & AT1 Receptor
List 5 products of Natriuretic peptides (BK, ADM Subs-P, VIP, CGRP)?
- Vasodilation
- Natriuresis (excretion of sodium in urine)
- Diuresis
- Inhibition of pathologic growth/fibrosis
- Degradation products
List the 3 different devices for heart failure?
- Implantable cardioverter-defibrillator (ICD)
- Biventricular/multi-site pacing or “cardiac resynchronisation” therapy with implantable cardioverter defibrillator (CRT- D)
- “Cardiac resynchronisation” therapy with pacing (CRT-P)
What drug inhibits the sinus node?
Ivabradine
What does SHIFT stand for?
Systolic Heart failure treatment with the inhibitor ivabradine Trial
What are the 2 types of ventricular assist devices?
- Pulsatile-Flow Left Ventricular Assist device
2. Continuous-Flow Left Ventricular Assist Device
What is SynCardia/ CardioWest?
Total artificial heart
What type of heart failure do we still not have evidence-based treatment for?
Heart failure with preserved ejection fraction
List 6 treatments for acute heart failure?
- Bilevel or continuous positive airway pressure (preload reduction)
- Dobutamine, dopamine, milrinone (increase inotropy)
- Furosemide (natriuresis)
- Nitrates, morphine (venodilation)
- Nitroprusside (arterial vasodilation)
- Ultrafiltration (aqual natriuresis)
What would you do for patients with cardiogenic shock in acute heart failure?
- Circulatory support (pharmacological, mechanical)
- Immediate stabilisation & transfer to ICU/CCU
What would you do for patients with respiratory failure in acute heart failure?
- Ventilatory support (oxygen, non-invasive positive pressure ventilation, mechanical ventilation)
- Immediate stabilisation & transfer to ICU/CCU
What is the CHAMP mnemonic for identification of acute aetiology?
- Coronary syndrome
- Hypertension emergency
- Arrhythmia
- Mechanical cause
- Pulmonary embolism
List the 7 clinical features of acute heart failure congestion?
- Pulmonary oedema
- Orthopnoea/Paroxysmal nocturnal dyspnoea
- Peripheral (bilateral) oedema
- Jugular venous dilatation
- Congested hepatomegaly
- Gut congestion, ascites
- Hepatojugular reflux
List the 4 clinical features of acute heart failure hypoperfusion?
- Cold sweating extremities
- Oliguria
- Mental confusion
- Dizziness
- Narrow pulse pressure
What would you get with hypoperfusion no congestion in acute heart failure?
Cold-dry (inadequate peripheral perfusion, hypovolemic)
What would you get with no hypoperfusion and no congestion?
Warm-dry (adequate peripheral perfusion = compensated)
What would you get with no hypoperfusion and positive congestion?
Warm-wet (adequate peripheral perfusion)
Would you get with hypoperfusion and congestion?
Cold-wet (inadequate peripheral perfusion)
Describe the blood pressure in a patient with warm-wet acute heart failure?
Elevated or normal systolic blood pressure
What are the 2 forms of warm-wet acute heart failure?
- Vascular type- fluid redistribution, hypertension predominates
- Cardiac type- fluid accumulation, congestion predominates
How would you treat vascular type warm-wet acute heart failure?
- Vasodilator
- Diuretic
How would you treat cardiac type warm-wet acute heart failure?
- Diuretic
- Vasodilator
- Ultrafiltration (consider if diuretic resistance)
How would you treat warm-dry acute heart failure?
Adjust oral therapy
How would you treat cold-dry acute heart failure?
- Consider fluid challenge
- Consider inotropic agent if still hypoperfused
Describe the blood pressure in a patient with cold-wet acute heart failure?
Systolic blood pressure <90mmHg or normal
How would you treat cold-wet acute heart failure with a decreased systolic blood pressure?
- Inotropic agent
- Consider vasopressor in refractory cases
- Diuretic (when perfusion corrected)
- Consider mechanical circulatory support if no response to drugs
How would you treat cold-wet acute heart failure with a normal systolic blood pressure?
- Vasodilators
- Diuretics
- Consider inotropic agent in refractory cases
What does the presence of congestion in acute heart failure indicate?
“Wet” patient
What does NO presence of congestion in acute heart failure indicate?
“Dry” patient
Describe stage 1 heart failure?
- Redistribution
- Pulmonary capillary wedge pressure (PCWP) 13-18mmHg
Describe stage 2 heart failure?
- Intersitial oedema
- Pulmonary capillary wedge pressure (PCWP) 18-25mmHg
Describe the chest X-ray appearance of stage 1 heart failure?
- Redistribution pulmonary vessels
- Cardiomegaly
Describe the chest X-ray appearance of stage 2 heart failure (interstitial oedema)?
- Kerley Lines
- Peribronchial Cuffing
- Hazy contours of vessels
- Thickened interlobar fissures
Describe stage 3 heart failure?
- Alveolar oedema
- PCWR >25mmHg
Describe the chest X-ray appearance of stage 3 heart failure (alveolar oedema)?
- Consolidation
- Air bronchogram
- Cottonwool appearance
- Pleural effusions
Describe class I congestive heart failure?
Pulmonary hypertension with no limitation of usual physical activity
Describe class II congestive heart failure?
- Pulmonary hypertension with mild limitations of physical activity
- No discomfort at rest, but normal physical activity causes increased dyspnea, fatigue, chest pain or pre-syncope
Describe class III congestive heart failure?
- Pulmonary hypertension with marked limitation of physical activity
- No discomfort at rest, but less than ordinary activity causes increased dyspnea, fatigue, chest pain or pre-syncope
Describe class IV congestive heart failure?
- Pulmonary hypertension, unable to perform any physical activity & who have signs of right ventricular failure at rest
- Dyspnea &/or fatigue may be present at rest & symptoms are increased by almost any physical activity
Where are the biggest vessels in a normal chest X-ray?
Vessels in lower zones are larger than equivalent vessels in upper zones
What should be considered when a chest X-ray shows upper zone vessels are equal to or greater than equivalent lower zone vessels?
Elevation of pulmonary venous pressure
What is the basic anatomic unit of pulmonary structure & function?
Secondary lobule (smallest lung unit that is surrounded by connective tissue septa)
What does the central terminal bronchiole supply?
5-15 pulmonary acini, that contain the alveoli for gas exchange
Describe Kerley B lines?
- Septal Lines: fluid leakage into interlobular septa
- Seen at the bases perpendicular to the pleural surface & measure 1-2cm
What is the diagnosis if the Kerley B lines are transient/rapidly developing?
Interstitial pulmonary oedema
Describe Kerley A lines?
Oblique lines longer than Kerley B lines
What are Kerley A lines caused by?
Distension of the anastomotic channels between
the peripheral & central lymphatics
Describe Kerley C lines?
Reticular opacities at the lung bases
Describe Peribronchial cuffing?
- Normally walls of bronchi are invisible
- When fluid collects in peribronchial interstitial space the bronchial walls become visible
Describe the hazy contour of vessels in interstitial oedema?
Vessels enlarge & lose their defined margin due to surrounding oedema, requires previous examinations
What is subpleural pulmonary oedema?
Fluid accumulated in the loose connective tissue beneath the visceral pleura
Describe the X-ray appearance of subpleural pulmonary oedema?
Sharply defined band of increased density:
- If adjacent to a fissure makes the fissure look thick
- When in costophrenic angle produces a lamellar-shaped fluid collection resembling a pleural effusion
What is alveolar oedema?
Represents spill of fluid from interstitium into alveolar spaces resulting in airspace opacity
Describe alveolar oedema?
- Bilateral usually
- If unilateral predisposition for right lung
- “Bat’s wing” or “Butterfly” distribution (perihilar shadowing predominantly in central portions & fades out)
- Rapid change
What are pleural effusions?
Fluid within potential space between parietal and visceral fluid
Describe pleural effusions?
- Divided into transudates & exudates
- Protein levels >30g/l, LDH>200IU, pH <7.1 consistent with exudate
Give 6 causes for transudate alveolar oedema?
- Left Ventricular failure
- Cirrhosis
- Nephrotic syndrome
- Myxoedema
- PE
- Sarcoidosis
Give 5 causes for exudate alveolar oedema?
- PE
- Bacterial infection
- Bronchial cancer
- Fungal/viral infection
- Lymphoma
What % of pleural effusions in chronic heart failure are bilateral?
70%
How much fluid in alveolar oedema must be present to be seen on a PA and supine chest X-ray?
PA- 175ml
Supine- 500ml
What can larger effusion cause?
Obscure heart border & displace mediastinum, airways & diaphragm
What are the 4 principle signs of subpulmonic effusion?
- Lateral peak of hemidiaphragm
- Costophrenic angle ill-defined or blunted
- Posterior costophrenic sulcus is fluid-filled
- On left increased distance between lung & gastric air bubble
What is the difference between acute & chronic heart failure?
AHF often used to mean new onset acute or decompensation of CHF characterised by signs of pulmonary +/or peripheral oedema
What is the definition of a valve?
Device for controlling the passage of fluid through a pipe or duct, especially an automatic device allowing movement in one direction only
List 5 possible abnormalities in the heart valve leaflets?
- Calcification
- Thickening
- Degeneration
- Infection
- Prolapse
List the 3 signs of acute rheumatic fever?
- Painful joints
- Fever
- Rash
Describe rheumatic valve disease?
- 1-3% of strep pyogenes throat infections
- Caused by antibody cross reactivity affecting connective tissue
- Cardiac injury generated by recurrent inflammation & fibrinous repair & scarring
- Less prevalent in antibiotic age
Describe the aortic valve?
- Lies between LV & aorta
- 3 cusps: trileaflet
- Right, left, non coronary
List 4 causes of aortic stenosis?
- Thickening
- Calcification
- Rheumatic valve disease
- Congenital
What does aortic stenosis cause?
- Increased LV cavity pressure
- Pressure overload –> LV hypertrophy
List the 5 symptoms of aortic stenosis?
- Shortness of breath
- Presyncope
- Syncope
- Chest pain
- Reduced exercise capacity
List 5 causes of aortic regurgitation?
- Degeneration
- Rheumatic valve disease
- Aortic root dilatation
- Systemic disease
- Endocarditis
Give 4 examples of systemic diseases which can cause aortic regurgitation?
- Marfan’s syndrome
- Ehlers Danlos syndrome
- Ankylosing Spondylitis
- SLE
What does aortic regurgitation cause?
- Volume overload
- LV dilatation
List the 2 symptoms of aortic regurgitation?
- Shortness of breath
2. Reduced exercise capacity
What % of the population have a bicuspid valve (two leaflet aortic valve instead of the normal 3 leaflet)?
1-2%
Describe the problem with the bicuspid valve (two leaflet aortic valve instead of the normal 3 leaflet)?
- Prone to premature dysfunction
- Associated with aortic abnormalities
- Genetic component (~10%)
Describe the mitral valve?
- Lies between LA & LV
- 2 leaflets
- Anterior & posterior
List 6 potential causes of mitral stenosis?
- Rheumatic valve disease
- Pressure overload
- Dilated LA
- Atrial fibrillation
- Pulmonary hypertension
- Secondary right heart dilatation
List the 5 symptoms of mitral stenosis?
- Shortness of breath
- Palpitation
- Chest pain
- Haemoptysis
- Right heart failure symptoms
List the 5 possible causes of mitral regurgitation?
- Volume overload – LA / LV
- LV & LA dilatation
- Pulmonary hypertension
- Secondary right heart dilatation
- Atrial fibrillation
List the 3 symptoms of mitral regurgitation?
- Shortness of breath
- Palpitation
- Right heart failure symptoms
Describe the pulmonic/pulmonary valve?
- 3 leaflets
- Lies between RV & pulmonary artery
- Issues tend to be a disease of childhood/early adulthood
Describe the tricuspid valve?
- 3 leaflets
- Lies between RA & RV
- Isses tend to be a disease of childhood but can also arise in adulthood
List 6 ways of investigating valvular heart disease?
- Echo
- CT
- MRI
- Exercise Tolerance Test
- Cardiopulmonary Exercise Testing (CPET)
- Stress echo
How can you diagnose valvular heart disease?
Left/Right heart catheterisation
What are 3 ways of treating valvular heart disease?
- Medication
- Surgical intervention- valve replacement
- Procedural intervention- TAVI, Mitraclip, valvuloplasty
What are the 4 factors to take into consideration when performing a valve replacement?
- Mechanical vs tissue valve
- Durability (age/life expectancy)
- Anticoagulation (compliance)
- “Next intervention”
What does TAVI stand for?
Transcatheter aortic valve implantation
Describe a TAVI?
- Non-surgical alternative to open heart surgery
- Carried out in a cardiac catheterisation laboratory
- Normally takes 1-2hrs
- Tube up from the leg to crush the original valve & inflate a large stent with the new valve inside
What is the Mitraclip typically for?
Mitral regurgitation when the patient isn’t fit for surgery
What is a valvuloplasty?
- Also known as balloon valvuloplasty/balloon valvotomy
- Repairs a heart valve that has a narrowed opening
- The valve flaps (leaflets) may become thick or stiff & they may fuse together (stenosis)
What is the Melody valve?
- Replacement pulmonary heart valve (stenosis)
- Used to replace a blocked or leaky valve that has been previously repaired to correct congenital heart defects present at birth
What is endocarditis?
- Infection of endocardium (lining of heart) & usually involves the heart valves
- Formation of a vegetation
- Results in damage to cusp of valves
List the 4 heart valves in order of whats most –> least likely to develop endocarditis?
- Mitral valve
- Aortic valve
- Tricuspid valve
- Pulmonary valve
Describe the vegetation in endocarditis?
Mass of platelets, fibrin, microcolonies of microorganisms & scant inflammatory cells
What are the 2 types of bugs causing endocarditis?
- Bacterial
2. Fungal
What is a common bacteria causing endocarditis?
Coxiella burnetii (Q fever)
What are 2 types of gram positive bacterial cocci causing endocarditis?
- Staphylococci
2. Streptococci
What are 2 types of Staphylococci bacteria causing endocarditis?
- Coagulase negative Staphylococci (CoNS)
2. Staph. aureus (MRSA, MSSA)
What are 2 types of Streptococci bacteria causing endocarditis?
- Strep. viridans
2. Enterococci
What is a common fungus causing endocarditis?
Candida species
What are 3 different types of gram negative bacteria causing endocarditis?
- HACEK organisms
- Pseudomonas aeruginosa
- Enterobacteriales (Coliforms) ie. E.coli
What are the 3 classifications of endocarditis?
- Native valve endocarditis (NVE)
- Endocarditis in IVDUs (intravenous drug user)
- Prosthetic valve endocarditis (PVE)
What is a common organism causing Native valve endocarditis (NVE)?
Streptococcus viridans
What are 3 common organisms causing Endocarditis in IVDUs?
- Staphylococcus aureus
- Gram Negative Organisms
- Fungi
What are 3 common organisms causing Prosthetic valve endocarditis (PVE)?
- Coagulase negative Staphylococci (CoNS)
- Gram Negative Organisms
- Fungi
Describe the general epidemiology of endocarditis?
- Common!
- Rates vary according to: age & incidence of IVDU
- 3x more common in men
- Increasing in elderly patients: 25-50% of cases occur in the over 60s
What are the risk factors for Native valve endocarditis (NVE)?
Underlying valve abnormalities in 55-75%
- Aortic stenosis
- Mitral Valve Prolapse (MVP)
What are the 3 different aetiologies of aortic stenosis?
- Age-related calcification in ~50%
- Calcification of congenitally abnormal valve ~30-40%
- Rheumatic fever ~10%
Describe the pathogenesis of strep pyogenes in rheumatic heart disease?
Infection –> Partially/Not Treated –> Liberation of the toxin –> Anti-Streptolysin O (ASO) Antibodies produced against Streptolysin –> Cardiac valve also attacked by antibodies –> Stenosis/Regurgitation
What valve is most likely to be affected in Endocarditis in IVDU?
Tricuspid valve endocarditis more common than aortic/mitral
List the 3 general clinical features of acute endocarditis?
- Toxic presentation
- Progressive valve destruction & metastatic infection developing in days to weeks
- Most commonly caused by S. aureus
List the 4 general clinical features of subacute endocarditis?
- Mild toxicity
- Presentation over weeks to months
- Rarely leads to metastatic infection
- Most commonly Strep. viridans or Enterococcus
Describe the early manifestations of endocarditis?
- Fever + Murmur = infective endocarditis until proven otherwise
- Fatigue & malaise
What is the incubation period of endocarditis?
2 weeks (longer in prosthetic valve endocarditis (PVE)
What % of endocarditis presents with a murmur?
80-85% (often absent in tricuspid endocarditis)
Describe the embolic events associated with endocarditis?
- Can take days-weeks to occur
- Seen earlier in acute endocarditis
- Small/Large emboli
- Right sided endocarditis- septic pulmonary emboli
Give 3 features of small emboli in endocarditis?
- Petechiae
- Splinter haemorrhages
- Haematuria
Give 2 features of large emboli in endocarditis?
- CVA (Stroke)
2. Renal infarction
What are the long term effects of endocarditis?
- Oslers nodes
- Immunological reaction
- Tissue damage
Describe Oslers nodes?
- Painful palpable lesions
- Found on hands & feet
List 4 immunological reactions seen in long term endocarditis?
- Splenomegaly
- Nephritis
- Vasculitic lesions of skin & eye
- Clubbing
List 2 forms of tissue damage seen in long term endocarditis?
- Valve destruction
2. Valve abscess
In what 3 scenarios would you think its infective endocarditis?
- All patients with S. aureus bacteraemia (SAB)
- IVDU with any positive blood cultures
- All patients with prosthetic valves & positive blood cultures
What is the most important investigation when diagnosing endocarditis?
Blood cultures
Describe how endocarditis is diagnosed?
- Constant bacteraemia
- 3 sets of blood cultures
- Volume most important factor (10mls/bottle)
- Before antibiotics
- Aseptic technique
What are the 2 different echocardiographs you can use to diagnose endocarditis?
- Transthoracic (TTE)
2. Transoesophageal (TOE)
Describe a Transthoracic (TTE) echocardiograph?
- Non-invasive
- Transducer placed at front of chest
- 50% sensitivity
Describe a Transoesophageal (TOE) echocardiograph?
- Invasive
- Transducer placed in oesophagus
- 85-100% sensitivity
What is major endocarditis according to the Duke Criteria?
- Typical organism in 2 separate blood cultures
- Positive echocardiogram or new valve regurgitation
What is minor endocarditis according to the Duke Criteria?
- Predisposition (heart condition or IVDU)
- Fever >38 ̊C
- Vascular phenomena (eg. septic emboli)
- Immunological phenomena (eg. oslers nodes)
- Positive blood cultures (not meet major criteria)
What are the 3 indications for surgical intervention for endocarditis?
- Heart failure
- Uncontrollable infection (abscess, Persisting fever + positive blood cultures >7 days, Infection caused by multi-drug resistant organisms)
- Prevention of Embolism (Large vegetations + embolic episode)
Describe antimicrobial therapy for endocarditis?
- Bactericidal agents at high doses
- Treatment tailored to organism susceptibility
- Duration of therapy (NVE: 4 weeks, PVE: 6 weeks)
- IV therapy for duration in most cases
What would the antimicrobial therapy be for endocarditis via Streptococcus species?
Benzylpenicillin +/- Gentamicin
What would the antimicrobial therapy be for endocarditis via Enterococcus species?
Amoxicillin or Vancomycin +/- Gentamicin
What would the antimicrobial therapy be for endocarditis via S.aureus (MSSA)?
Flucloxacillin +/- Gentamicin
What would the antimicrobial therapy be for endocarditis via S.aureus (MRSA)?
Vancomycin +/- Gentamicin
What would the antimicrobial therapy be for endocarditis via Coagulase Negative Staphylococci (CoNS)?
Vancomycin +/- Gentamicin +/- Rifampicin
What are the 3 purposes of cardiovascular imaging?
- Define the structure/anatomy of the heart
- Detail the function or physiology (valve function, coronary physiology)
- Image the heart during stress (provoke ischaemia, assess valve function)
What are the 2 basic forms of cardiovascular imaging?
- CXR
2. ECG
What are the 3 advanced forms of cardiovascular imaging?
- Ultrasound (Transthoracic Echocardiography, Transoesophageal Echocardiography)
- Ionising radiation (nuclear, CT, invasive angiography)
- MRI
What does an ECG do?
- Visual representation of the electrical activity of the heart
- Abnormalities of rhythm, conduction, repolarisation
What is the coronary difference between STEMI & NSTEMI?
- STEMI: coronary blocked/no flow
- NSTEMI: coronary partially blocked/persistent flow
What 5 things does a chest X-ray show?
- Cardiac silhouette (size & position)
- Pulmonary vasculature
- Great vessels
- Pulmonary oedema
- Pleural effusions
What are the 4 standard views of the heart in imaging?
- Left parasternal long axis view (PLAX)
- Short axis view of left ventricle (PSAX)
- Short axis view, aortic valve (PSAX)
- Apical four chamber view
What 3 things can an echo doppler show on cardiovascular imaging?
- Assessment of flow
- Valve function
- Pericardial effusion
- Ejection fraction
Describe contrast echocardiography?
- Technique for improving echocardiographic resolution & providing real time assessment of intracardiac blood flow
- Inject tiny bubbles into the venous system & they refract ultrasound beams
Describe a Transoesophageal echocardiograph (TEE)?
- Invasive but safe
- TEE probe into mouth & down oesophagus
- TEE probe can also be placed in the stomach
- Sound waves create pictures of the heart
- Patient lies on left side
What are the 4 indications for echocardiography?
- Structure + function of heart
- Valve assessment
- Pericardial assessment
- Assess inducable ischaemia (stress)
What are the 4 PROS of echocardiography?
- Cheap
- Available
- Portable
- No radiation
What are the 2 CONS of echocardiography?
- Requires good acoustic window
2. User dependent
What are the 3 types of functional stress testing (imaging for ischaemia)?
- Exercise stress testing
- Nuclear stress testing
- Echo stress testing
What are the 2 indications for nuclear perfusion imaging?
- Assess ischaemia
2. Assess ejection fraction
What are the PROS & CONS of nuclear perfusion imaging?
- PROS: availability
- CONS: radiation, no structural assessment
What would we use a coronary artery calcium scan for?
- Refine clinically predicted risk of CHD beyond that predicted by standard cardiac risk factors
- Used in asymptomatic patients
What is coronary calcium present in direct proportion to?
Extent of atherosclerosis (20% of plaque is calcified)
What are the 2 indications for cardiac CT?
- Coronary artery anatomy
2. Great vessel anatomy
What are the 2 PROS of cardiac CT?
- Good “rule out” for CAD
2. Low risk
What are the 3 CONS of cardiac CT?
- Radiation dose
- Requires low heart rate
- No functional assessment of ischaemia
Describe hwo to perform a coronary angiography?
- Percutaneously pass wires through the radial arteries, then pass a catheter to directly inject contrast into the coronary arteries
- Then we image these to look for any stenosis
What are the 4 indications for invasive angiography?
- Ischaemia
- Primary PCI
- Valve assessment
- Assessment ventricular pressures R+L
What are the 3 PROS for invasive angiography?
- Gold standard
- Option for intervention during same procedure
- Availability
What are the 2 CONS for invasive angiography?
- Radiation
2. Risks: CVA, MI, contrast reaction, bleeding & death
What is the contrast used in cardiac MRIs?
Gadolinium to assess scar tissue (fibrosis)
What are the 4 indications for cardiac MRI?
- Assess structure & function
- Perfusion/stress
- Assess great vessels
- Tissue characterisation (infiltrative cardiomyopathies, precious infarction)
What are the 3 PROS for cardiac MRI?
- Gold standard LV assessment
- Reproducable
- No radiation
What are the 4 CONS of cardiac MRI?
- Cost
- Availability
- Clostrophobia
- Pacemakers
What is the most detailed way to assess heart function?
Cardiac MRI
What 2 things can an aortic root abscess cause?
- Heart block
2. NSTEMI- coronary artery involvement
List the 8 potential symptoms of an MI?
- Chest pain
- Back pain
- Jaw pain
- Indigestion
- Sweatiness, clamminess
- Shortness of breath
- None (diabetes/dementia)
- Death
List the 6 potential signs of an MI?
- Tachycardia
- Distressed patient
- Heart Failure (crackles/ raised JVP)
- Shock
- Arrhythmia
- None
What is troponin?
- Part of the cardiac myocyte
- Release into blood stream is a marker of cardiac necrosis
- High sensitivity troponin (able to detect very small MIs)
What is the universal definition of MI?
Any elevation in troponin in clinical setting consistent with myocardial ischaemia
What are the different types of MI?
- Type 1
- Type 2
- Type 3
- Type 4a
- Type 4b
- Type 5
Describe type 1 MI?
Spontaneous MI due to a primary coronary event (coronary artery plaque rupture & formation of thrombus)
Describe type 2 MI?
Increased oxygen demand or decreased oxygen supply
Describe type 3 MI?
Sudden cardiac death
Describe type 4a MI?
MI associated with percutaneous coronary intervention (doctor induced)
Describe type 4b MI?
MI Stent thrombosis documented by angiography or post mortem (doctor induced)
Describe type 5 MI?
MI associated with CABG (doctor induced)
Describe the condition of the coronary arteries in type 2 MI?
- Fixed atherosclerosis & supply-demand imbalance OR
- Supply-demand imbalance alone
List the 6 causes of type 2 MI’s?
- Congestive heart failure- acute
- Tachy-arrhythmias
- Pulmonary embolism
- Sepsis
- Apical ballooning syndrome (Takosubo cardiomyopathy)
- Anything that stresses the heart (eg critically unwell patient)
List 3 non coronary causes of chronic elevated troponin (not an MI)?
- Renal failure
- Chronic heart failure
- Infiltrative cardiomyopathies eg amyloidosis, hemochromatosis, sarcoidosis
What is unstable angina?
An acute coronary event without a rise in troponin
Give 2 examples of unstable angina presentations?
Clinical presentation of an MI + ECG changes
Or
Tight narrowings on coronary angiography
How is unstable angina rare now?
Because of high sensitivity troponin
What 3 conditions could an NSTEMI be?
- Unstable angina
- Non-Q-wave acute myocardial infarction (NQMI)
- MI
What 2 conditions could a STEMI be?
- Q wave myocardial infarction (Qw MI)
2. MI
What does ST elevation on an ECG reflect?
Occlusion of a coronary artery (occurs in regional patterns)
Describe a posterior infarct on the ECG?
Location means ST elevation not seen
Describe a left bundle branch block on the ECG?
- If NEW can indicate infarction
- If OLD can obscure ST elevation during an infarct (always ask senior advice as to whether to treat as a STEMI or not)
What coronary arteries are affected in an inferior infarct?
RCA (mostly) or Left circumflex artery
What coronary arteries are affected in a posterior infarct?
Circumflex (mostly) or RCA
What coronary arteries are affected in a lateral infarct?
Left circumflex artery
What coronary arteries are affected in an anteroseptal infarct?
LAD
What are the 2 ECG anterior leads?
- aVR
2. V1-6
What are the 2 ECG lateral leads?
- aVL
2. Lead I
What are the 3 ECG inferior leads?
- Lead III
- aVF
- Lead II
What leads would show reciprocal ST depression in an anterior STEMI?
Lead II&III, aVF (inferior leads)
What leads would show ST elevation in a high lateral STEMI?
- Lead I
- aVL
(often missed)
What leads would show reciprocal ST depression in a high lateral STEMI?
Lead II&III & aVF
inferior leads
What leads would show reciprocal ST depression in an inferior STEMI?
Lead I & aVL
high lateral leads
Describe the ECG appearance with a posterior wall infarction?
- No ECG leads look directly at the posterior wall of the heart
- Anterior leads are directly opposite = anterior ST depression
- Often associated with inferior/lateral ST elevation
Describe the ECG appearance with a left bundle branch block?
- QRS >120ms-1 (3 small squares)
- Dominant S wave in V1
- Deflected QRS in V1
- Broad R wave with deep S wave & inverted T wave in V6
What are the 9 steps to immediate management of a STEMI?
- ABCDE assessment
- Put in an ambulance attached to defibrillator
- Aspirin 300mg PO
- Unfractionated heparin 5000U IV
- Morphine 5-10mg iv
- Anti-emetics
- Clopidogrel (in ambulance)
- Ticagrelor 180mg (in hospital)
- Activate PPCI team at Golden Jubilee National Hospital
What are the 2 different doses of Clopidogrel for management of a STEMI?
- 600mg if for PPCI
2. 300mg if for Thrombolysis (75mg if aged > 75)
What 6 benefits are there to using PCI instead of thrombolysis in a STEMI?
- Improves survival
- Reduces strokes
- Reduces the chance of further MI
- Reduces the chance of further angina
- Speeds up recovery
- Shortens the time spent in hospital
What should the median door to balloon time be (DBT)?
<30mins
What are the 5 steps to subsequent management for a STEMI?
- Monitor in Coronary Care Unit for complications of MI
- Drugs for secondary prevention
- Echocardiogram for LV function & cardiac structure
- Cardiac rehabilitation
- If LVSD at >9 months consider primary prevention ICD
List the 4 drugs you would give an MI patient for secondary prevention?
- ACE inhibitors
- Beta blockers
- Statins
- Eplerenone (potassium-sparing diuretic)- only for diabetes & LVSD/clinical HF
List the 5 complications of an MI?
- Arrhythmias (VT/AF)
- Heart failures
- Cardiogenic shock (intra-aortic balloon pump)
- Myocardial rupture
- Psychological (anxiety, depression, cardiac rehab)
Describe the 3 different types of myocardial ruptures in MI complications?
- Septum- Ventricular Septal Defect- surgery
- Papillary muscle- mitral regurgitation- surgery
- Free wall- tamponade- usually fatal
What does IABP stand for?
Intra-aortic balloon pump = ventricular assist device
List the 4 step subsequent management plan for an NSTEMI?
- Monitor in Coronary Care Unit for complications of MI (Aspirin, Clopidogrel or ticagrelor, Low molecular weight heparin or fondaparinux)
- Drugs for secondary prevention
- Echocardiogram for LV function & cardiac structure
- Cardiac Rehabilitation
What scoring system is used to assess someones ACS risks?
GRACE score (low, intermediate & high)
Describe the relevance of Timing of Coronary Revascularisation in NSTEMI (TIMACS)?
- Randomised to early (< 24h) or delayed (minimum 36h, median 50h) angiography+/- PCI
- No significant reduction in death/MI
- Substantial benefit in high risk group
- No benefit in lower risk groups
If patients “stabilise” post admission what do the WoS guidelines suggest?
- Low risk: discharge on medical treatment
- Intermediate risk: discharge to be readmitted for
angiogram within 1-2/52 - High risk (GRACE>140): urgent inpatient angiogram
- ALL VIA SCI gateway: E-REFERRAL
What does DAPT stand for?
Dual anti-platelet therapy
Give an example of a P2Y12 inhibitor?
Ticagrelor
What is the recommended DAPT treatment for type I MI?
P2Y12 inhibitor (ticagrelor), in addition to aspirin, for 12 months unless there are contradictions such as excessive risk of bleeds
What is the recommended DAPT treatment for type IIb MI?
P2Y12 inhibitor (ticagrelor) for 3-6months after DES implantation may be considered in patients deemed at high bleeding risk
What is the recommended DAPT treatment for type IIb MI?
P2Y12 inhibitor (ticagrelor) in addition to aspirin for beyond 1hr may be considered after careful assessment of the ischaemic & bleeding risks of the patient
What are the 5 peri-operative CVS complications?
- Surgical stress response
- Altered myocardial O2 supply/demand
- Fluid shifts
- Altered coagulation
- Disruption to medication
What 4 things do you look at to work out if you can safely anaesthetise a patient?
- Risk
- Optimisation
- Myocardial oxygen supply/demand
- Peri-operative pitfalls
What 4 questions do you want to ask in a heart disease pre-surgical history?
- Normal status for patient?- onset, symptoms, duration, relief, frequency, Stable/unchanged OR unstable/deteriorating
- New/worrying features-
Symptoms at rest or minimal exertion, Orthopnoea - Treatment?
- Previous (recent) anaesthesia?
What are 4 conditions requiring further action before heart surgery?
- Unstable coronary syndromes
- Decompensated heart failure
- Significant arrhythmias
- Severe valve disease
What is the ASA scoring system in assessing a patients peri-operative risk?
1 = healthy 2 = mild systemic disease 3 = severe systemic disease 4 = severe disease / constant threat to life 5 = moribund 6 = organ donor E = emergency
What is the metabolic equivalent of task (METs) in assessing a patients peri-operative risk?
1 MET = basal metabolic... TV 3 METs = walking 100m flat 4 METs = one flight stairs / gardening 7 METs = jogging 10 METs = strenuous sport
_______ METs is associated with increased peri-operative risk?
<4 METs
When is Lee’s Revised cardiac risk index used?
- Validated for elective surgery
- Predicts cardiac event rate
Describe Lee’s Revised cardiac risk index?
- High risk surgery = 1pt
- Ischaemic heart disease = 1pt
- History heart failure = 1pt
- Cerebrovascular disease = 1pt
- Insulin therapy = 1pt
- Creatinine > 177μmol/l = 1pt
What is the % risk for a Lee’s Revised cardiac risk index score of 0,1,2 and ≥3 pts?
- 0pts= 0.4%
- 1pt= 0.9%
- 2pts= 6.6%
- ≥3pts=11%
How would you optimise a patient before heart surgery?
- Meet patient, discuss issues, allay fears: bloods, G&S, ECG etc. Anaemia: diagnose & treat
- Take correct meds!
- Minimise fasting & keep hydrated
- Operating list management / communication
- Prophylactic revascularisation? Not unless needed anyway
Describe the myocardial oxygen supply?
- Oxygen content of blood
- Coronary blood flow: CO/MAP, HR / diastolic time, Anatomy/pathophysiology
Describe the myocardial oxygen demand?
- Heart rate
- Contractility
- Pre-load
- Afterload
What is the amount of oxygen that a haemoglobin will carry?
1.34mls
What is the amount of oxygen dissolved in the blood?
0.003
Describe how to avoid the peri-operative pitfalls?
- Specific technique probably less important than prerequisite skill & care
- Maintain optimal hydration (not ’dry’ or ‘wet’) & early return to normal diet
- Adequate analgesia intra/post operatively
- Avoid post-op N/V
- Normal medications as appropriate
- Early mobilisation
Describe the 3 structural components of the anatomical heart?
- Atrial chambers- Atrioventricular valves
- Ventricular mass- Ventriculoarterial valves
- Great arteries
Describe the morphology of the right ventricle?
Trabeculated endocardium, insertion of chordae to interventricular septum, moderator band
Describe the morphology of the left ventricle?
Smooth endocardium, sphere cavity
Describe the morphology of the right atrium?
- Sinoatrial node
- Broad appendage
Describe the morphology of the left atrium?
- Narrow
- Long appendage
What are the 2 forms of atrial septal defects?
- Secundum (most common)
2. Primum
What is the difference between the secundum & primum atrial septal defect (ASD)?
Primum is far more complex & better thought of as ‘partial AVSD’
Describe the Secundum ASD?
- Shunts left to right when in isolation
- Right heart volume loading
What would the examination show in Secundum ASD?
- Pulmonary flow murmur
- Fixed, split second heart sound
What 5 things may Secundum ASD lead to?
- RV failure
- Tricuspid regurgitation
- Atrial arrhythmias
- Pulmonary hypertension
- Eisenmenger syndrome
Describe a coarctation of the aorta?
- Highly variable in severity
- Tends to form after LSA in a ‘juxta-ductal’ position
- Age at presentation depends on position and severity
What can a pre-ductal coarctation of the aorta cause?
Lower limb cyanosis
List the 4 clinical signs of coarctation of the aorta?
- Upper body hypertension
- Berry aneurysms
- Claudication
- Renal insufficiency
What does a coarctation of the aorta have a strong association with?
Bicuspid aortic valve
What may be present in a Chest X-ray of coarctation of the aorta?
Rib notching due to retrograde flow from high pressure anterior intercostal arteries to low pressure posterior
What are the 3 ways that you can surgically repair a coarctation of the aorta via thoracotomy?
- Subclavian flap
- End to end
- Jump graft
What clinically is common in coarctation of the aorta?
Accelerated coronary artery disease & may suggest a more generalised arteriopathy
What is a Cyanotic lesion?
- Group-type of congenital heart defect (CHD) that occurs due to deoxygenated blood bypassing the lungs & entering the systemic circulation OR
- Mixture of oxygenated & unoxygenated blood entering the systemic circulation
Describe the foetal circulation?
- In-utero oxygenation is by the maternal placenta
- Pulmonary circulation is minimal & at high resistance
- Of the blood that is pumped to the pulmonary artery via the right ventricle, most passes to the aorta via the ductus arteriosus
Describe the pathway of oxygenated blood in the foetal circulation?
- Returns to RA via IVC
- It then bypasses the RV/PA via the foramen ovale
Describe Transposition of the great arteries?
- Congenital
- Abnormal development of the fetal heart during the first 8 weeks of pregnancy
- Aorta is connected to the R ventricle & the pulmonary artery is connected to the L ventricle (swap)
Describe what happens in an atrial switch operation?
A baffle or channel is created to redirect the blood flow within the heart
What heart chamber ends up pumping blood to the systemic circulation in an atrial switch?
Right ventricle (not designed for this role and can therefore begin to fail)
List the 4 complications of an atrial switch operation?
- Dilatation
- Tricuspid regurgitation
- Heart failure
- Atrial arrhythmias
Describe what happens in an arterial switch operation?
- Aorta is detached from the R atrium (above the valve) & connected to the L atrium
- Pulmonary artery is detached (above the valve) from the L atrium and tied to the R atrium
- Coronary arteries are cut out of the pulmonary artery & attached to the aorta
What heart chamber ends up pumping blood to the systemic circulation in an arterial switch?
Left ventricle
What is the possible complication with an arterial switch?
Coronary artery complications
What are the 4 defects associated with Tetralogy of Fallot?
- Ventricular septal defect
- Overiding aorta
- Right ventricular outflow tract tachycardia (RVOT)
- Right ventricular hypertrophy
What are the 2 operations available for Tetralogy of Fallot?
- BT shunt
2. Complete repair
Describe a BT shunt for Tetralogy of Fallot?
- Surgical procedure used to increase pulmonary blood flow for palliation in duct dependent cyanotic heart defects
- Patient will not have a recordable blood pressure
Describe the 3 steps to complete repair of Tetralogy of Fallot?
- Pulmonary artery & R ventricle enlarged using a patch
- Muscular obstruction is removed
- VSD close with a patch
What 3 things can happen when repairing Tetralogy of Fallot?
- Significant pulmonary regurgitation- RV dilatation +/- dysfunction
- Arrhythmia- Particularly ventricular tachycardia (SVT with RBBB can be similar)
- Pulmonary arterial/branch PA stenoses
Describe a Univentricular Heart?
- Rare within CHD
- 1 functioning ventricle reliant on shunts for mixing of the blue & red blood
- The aim of surgery will always be to create 2 functioning ventricles
What may be created if surgery is not feasible in the treatment of a Univentricular Heart?
Fontan circulation will be created
What 4 anatomical factors can lead to a Univentricular Heart?
- Opening between ventricles (VSD)
- Underdeveloped right ventricle
- Opening between atria (ASD)
- Absent tricuspid valve
Describe a Fontan Circulation?
- IVC & SVC are directly plumbed into the pulmonary arteries bypassing the heart altogether
- The single functional ventricle is used to support the systemic circulation
What does the pulmonary circulation depend on?
High systemic venous pressure & low pulmonary vascular resistance
What are the 4 issues with a Fontan Circulation?
- PE- due to increased pulmonary vascular resistance
- Arrhythmia- due to increased preload & stroke volume affected
- Dehydration- reduced systemic venous pressure
- Bleeding- collapses systemic circulation
What may heart shunts be?
Cyanotic or not cyanotic
What 3 things defines systemic hypertension?
- Persistent elevation in arterial BP >140/90mmHg
- BP level that increases the vascular risk in patients sufficient to require intervention
- Threshold at which benefits of action (i.e. therapeutic intervention’) exceed those of inaction
What has a linear relationship with blood pressure?
CV events such as MI, stroke, heart failure & PVD
What are the 3 pathophysiological factors of hypertension?
- Defects in renal sodium haemostasis
- Functional vasoconstriction
- Defects in vascular smooth muscle growth & structure
What 2 physiological abnormalities result in hypertension?
- Increased cardiac output (autoregulation)
2. Increased total peripheral resistance
List what systemic hypertension is an independent risk factor for?
Development of coronary artery disease, cerebrovascular disease, peripheral artery disease & heart failure
Describe the effect of hypertension on risk of CV mortality?
Cardiovascular disease risk doubles for every 20mmHg increase in systolic & 10mmHg increase in diastolic pressure
List the 7 classifications of hypertension?
- Optimal (<120/80)
- Normal (120-129/80-84)
- High normal (130-139/85-89)
- Grade 1 hypertension (140-159/90-99)
- Grade 2 hypertension (160-179/100-109)
- Grade 3 hypertension (>180/110)
- Isolated systolic hypertension (>140/<90)
Describe Primary Hypertension?
- 90-95% cases of hypertension
- No identificable cause
- Associated with non-modifiable/modifiable risk factors
List the 4 non-modifiable risk factors for primary hypertension?
- Age
- Gender
- Ethnicity
- Genetic factors
List the 5 modifiable risk factors for primary hypertension?
- Diet (high salt, low fruit/veg)
- Physical activity
- Obesity
- Alcohol in excess
- Stress
List the 5 possible causes of secondary hypertension?
- Endocrine- hyperaldosteronism, phaechromocytoma, thyroid disorders, Cushing’s syndrome
- Vascular- co-artation of aorta
- Renal- renal artery stenosis, renal parenchymal disease
- Drugs- NSAID, herbal, cocaine, exogenous steroid
- Other- obstructive sleep apnoea
What does uncontrolled hypertension do?
Affects specific organ groups leading to end organ damage
List the 4 possible complications of hypertension?
- Stroke (35-40%)
- MI (20-25%)
- Heart failure (50%)
- Renal failure (35-40%)
Describe the clinical presentation of hypertension?
- Generally asymptomatic, discovered incidentally
- Uncommonly associated with headache & visual disturbance
What should a hypertension diagnosis not be made on?
A single elevated BP reading, there needs to be at least 2 readings, 5mins between readings over at least 2 visits
Describe 24 hour ambulatory blood pressure monitoring?
- Portable measurement device
- BP taken 20-30 mins throughout the day, 2 hourly overnight
Describe home blood pressure monitoring?
2 readings, twice a day, taken over 4-7 days
What is the office BP definition of hypertension?
- SBP= >140mmHg
&/or - DBP= >90mmHg
What is the ambulatory BP definition of hypertension?
- Daytime/awake mean= SBP >135mmHg &/or
DBP >85mmHg - Nighttime/asleep mean= SBP >120mmHg &/or DBP >70mmHg
- 24hr mean= SBP >130 &/or DBP >80mmHg
What is the home BP definition of hypertension?
- SBP= >135mmHg
&/or - DBP= >85mmHg
Describe the 4 diagnostic evaluation steps of a patient with hypertension?
- Confirm the diagnosis with an out of office blood pressure monitoring
- Assess cardiovascular risk
- Determine the presence of end organ damage or associated complications (e.g. IHD, CKD, PVD, CVA)
- Assess presence of secondary hypertension
What are the 6 factors to ask about in a hypertensive patients history?
- Risk factors
- Family history
- Relevant medical condition- CKD, OSA, Diabetes
- Established complications- stroke, IHD, heart failure, PVD
- Current & past BP medications
- Other Drugs
List 6 other drugs which are relevant in a hypertensive history?
- OCP
- Liquorice
- Steroids
- NSAIDS
- Cyclosporin
- Illicit substances
List the 11 things that you would assess in a hypertensive examination?
- BP measured both arms
- Weight/BMI
- Xanthelasma
- Pulses
- Oedema
- Rashes
- Heart- murmurs
- Lungs- failure
- Abdomen- renal masses
- Vascular bruits- kidneys, carotids
- Eyes
List the 7 initial investigations that you would do in a hypertensive patient?
- U&Es
- Glucose/HbA1c
- Lipid profile
- TFTs
- LFTs
- Urine dipstick +/- ACR
- 12-lead ECG (?LVH)
List the 5 additional tests that you would do in a hypertensive patient?
- Renin & aldosterone (primary hyperaldosteronism)
- 24hr urine catecholamines (phaechromocytoma)
- Echo
- Renal ultrasound
- MRA renal
How would you assess a patients CV risk?
- Based on BP category, presence of end organ damage, presence of diabetes, CV or renal disease
- There are various calculators available to calculate CV risk (QRISK, ASSIGN SCORE)
What are the 3 ways to manage hypertension?
- Lifestyle measures
- Pharmacological management
- Device based therapies
List the 6 lifestyle interventions for hypertension?
- Exercise
- Weight loss (10kg)
- Reduction in sodium intake (6g NaCl)
- Reduction in alcohol intake
- DASH diet
- Smoking cessation
How do we treat a high normal BP (130-139/85-89mmHg)?
- Lifestyle advice
- Consider drug treatment in very high risk patients with CVD, esp coronary artery disease
How do we treat a grade 1 hypertensive patient (BP 140-159/90-99mmHg)?
- Lifestyle advice
- Immediate drug treatment in high/very high risk patients with CVD, renal disease or hypertension-mediated organ damage (HMOD)
- Drug treatment in low moderate risk patients without CVD, renal disease or HMOD after 3-6months of lifestyle intervention if BP not controlled
How do we treat a grade 2 hypertensive patient (BP 160-179/100-109mmHg)?
- Lifestyle advice
- Immediate drug treatment in all patients
- Aim for BP control within 3months
How do we treat a grade 3 hypertensive patient (BP >180/110mmHg)?
- Lifestyle advice
- Immediate drug treatment in all patients
- Aim for BP control within 3months
What are the 4 types of pharmacological managements for hypertension?
- Diuretics
- ACE-i/angiotensin II receptor blockers (ARB)
- Vasodilators
- Others ie. methyldopa, hydralazine, monoxidine
What are 3 types of diuretics?
- Loop
- Thiazide
- Potassium sparing
What are 3 types of vasodilators?
- Calcium channel blockers
- Beta blockers
- Alpha blockers
What step 1 antihypertensive drug treatment would you use in a patient under 55years?
ACE inhibitor or low-cost angiotensin II receptor blocker (ARB)
What step 2 antihypertensive drug treatment would you use in a patient under 55years?
- ACE inhibitor or low-cost angiotensin II receptor blocker (ARB) +
- Calcium-channel blocker (CCB)
What step 3 antihypertensive drug treatment would you use in a patient under 55years?
- ACE inhibitor or low-cost angiotensin II receptor blocker (ARB) +
- Calcium-channel blocker (CCB) +
- Thiazide-like diuretic
What step 4 antihypertensive drug treatment would you use in a resistant patient?
- ACE inhibitor or low-cost angiotensin II receptor blocker (ARB) +
- Calcium-channel blocker (CCB) +
- Thiazide-like diuretic +
- Consider further diuretic or alpha- or beta-blocker +
- Referral
What step 1 antihypertensive drug treatment would you use in a patient over 55years/ black person of African/Caribbean origin of any age?
Calcium-channel blocker (CCB)
What 4 factors are taken into consideration when choosing the most appropriate anti-hypertensive for a patient?
- More important to achieve control of BP rather than “fret” over the choice of anti-hypertensives
- Co-morbidities
- Marked differences between drugs in side effect profile
- Often, more than 1 drug will be required
Give 3 examples of how co-morbidites can affect how you chose an anti-hypertensive drug?
- Beta-blockers in heart failure/ asymptomatic coronary heart disease
- ACEi in heart failure
- ACEi in diabetes mellitus
What did a meta-analysis on 11,000 patients from 42 anti-hypertensive drug trials show?
Combination therapy is ~5x more effective than increasing the dose of 1 drug (monotherapy; stepped care approach)
What are the BP treatment targets?
- <140/90
- Ideally <130/80 if tolerated
Give 2 examples of device based therapies used in hypertension management?
- Renal denervation
2. Baroceptor stimulation
Describe the prevalence of atrial fibrillation?
- Commonest sustained cardiac arrhythmia
- Affects 1.5-2% of the population
- A major risk factor for stroke (5-fold increase)
Describe the symptoms of atrial fibrillation?
- Asymptomatic
- Palpitation
- Dyspnoea
- Rarely, chest pain, syncope
- May present with complications, e.g. stroke
What are the 2 factors to diagnosing atrial fibrillation?
- Irregular pulse: “irregularly irregular”, confirmed by 12-lead ECG
- May require prolonged ambulatory ECG recordings to detect paroxysmal AF
What are the 3 types of atrial fibrillations?
- Paroxysmal intermittent, starting & stopping
- Persistent- needs intervention to terminate the arrhythmia, e.g. IV antiarrhythmic injection/DC cardioversion
- Permanent
Describe the ECG appearance of atrial fibrillation?
- Rate variable
- Irregular, narrow QRS - No P waves
Describe the ECG appearance of atrial flutter?
- Rate variable
- Regular narrow QRS
- Sawtooth atrial activity 300bpm, variable AV block
Describe the prevalence of atrial flutter?
- More common with increased age
- More common in males
List 11 conditions which predispose to the progression of atrial fibrillation?
- Hypertension
- Symptomatic heart failure
- Valvular heart disease
- Cardiomyopathies
- Atrial septal defects
- Coronary artery disease
- Thyroid dysfunction
- Obesity
- Diabetes mellitus
- COPD
- Chronic renal disease
What are the 5 objectives for atrial fibrillation treatment?
1. Prevention of stroke 2. Symptom relief 3. Optimum management of concomitant cardiovascular disease 4. Rate control 5. +/- Correction of rhythm disturbance
What are the 4 essential investigations for atrial fibrillation?
- ECG
- Echocardiogram
- Thyroid Function Tests
- Liver Function Tests
What is the target heart rate for atrial fibrillation?
- <110/min
- If still symptomatic, aim for <80/min
What should AF patients without heart failure be started on?
- Beta-blocker (bisoprolol 2.5-5mg OD or Atenolol 25-50mg BD)
OR - Rate-limiting Ca2+ antagonist (Verapamil MR 120-240mg OD)
What is the 2nd line treatment for atrial fibrillation?
Digoxin
What are the 3 major risk factors for stroke & thrombi-embolism in non-valvular AF?
- Previous stroke
- TIA or systemic embolism
- Age >75 years
What are the 6 clinical relevant non-major risk factors for stroke & thrombi-embolism in non-valvular AF?
- CHF or moderate-severe LV systolic dysfunction (LV EF <40%)
- Hypertension
- Diabetes mellitus
- Age 65-74years
- Female sex
- Vascular disease
Describe the stroke risk factor-based point-based scoring system for AF patients (CHA2DS2-VASc)?
- Congestive heart failure/LV dysfunction= 1
- Hypertension= 1
- Age >75= 2
- Diabetes mellitus= 1
- Stroke/TIA/thrombo-embolism= 2
- Vascular disease= 1
- Age 65-74= 1
- Sex category (female)= 1
What is the main issue with warfarin?
Narrow therapeutic window (can cause intracranial bleed)
List the 4 new oral anticoagulant drugs (NOACs) & what they work on?
- Dabigatran- Thrombin inhibitor
2. Rivaroxaban- Factor Xa inhibitor
3. Apixaban- Factor Xa inhibitor
4. Edoxaban- Factor Xa inhibitor
Describe the clinical pharmacology of Apixaban?
- ~50% oral bioavailability
- Not a pro-drug
- No food effects
- ~27% renal clearance
- 12hr t1/2
- 3-4hr Tmax
Describe the clinical pharmacology of Rivaroxaban?
- 80-100% oral bioavailability
- Not a pro-drug
- 20mg & 15mg doses need to be taken with food
- ~33% renal clearance
- 5-9hr t1/2 in young, 11-13hr t1/2 in elderly
- 2-4hr Tmax
Describe the clinical pharmacology of Dabigatran?
- ~6.5% oral bioavailability
- Pro-drug
- No food effects
- 85% renal clearance
- 12-16hr t1/2
- 0.5-2hr Tmax
Describe the clinical pharmacology of Edoxaban?
- 62% oral bioavailability
- Not a pro-drug
- No food effects
- 50% renal clearance
- 10-14hr t1/2
- 1-2hr Tmax
What 4 main effects did the meta-analysis of NOACs trials show?
- Reduced stroke / systemic embolism by 19%
- Reduced all-cause mortality by 10%
- Reduced intracranial haemorrhage by 52%
- Increased risk of GI bleeding
What is the management for an AF patient with a CHA2DS2-VASc score of 0?
No antiplatelet or anticoagulant treatment
What is the management for an AF patient with a CHA2DS2-VASc score of 1?
Oral anticoagulants should be considered (IIaB)
What is the management for an AF patient with a CHA2DS2-VASc score of >2?
Oral anticoagulants indicated (NOAC, warfarin) but assess for contra-indications & correct reversible bleeding risk factors
What treatment may be considered in patients with clear contra-indications for Oral anticoagulants?
Left atrial appendage occlusion devices
What is IIaB treatment?
Catheter ablation
What are the 5 types of patients that need to be referred for operation specialist assessment?
- Still symptomatic despite adequate rate control
2. Young age (<60)
3. Inadequate rate control despite β blocker (or Ca++ antagonist) + digoxin
4. Structural heart disease on echo
5. AF & coexisting heart failure
When would “rhythm control” be affective in AF patients?
Younger patients & patients with ongoing symptoms despite good rate control
What are the 3 options for rhythm control in AF patients?
- Direct current cardioversion (for persistent AF)
- Antiarrhythmic drugs
- Catheter ablation
What are the 3 types of Antiarrhythmic drugs used in the treatment of AF?
- Class 1 (Na+ channel blockers)
- Class 3 (K+ channel blockers, prolong action potential duration / QT interval)
- Multichannel blockers
Give 2 examples of Class 1 Antiarrhythmic drugs used in AF treatment?
- Flecainide 100mg bd
2. Propafenone 150-300mg bd
Give 2 examples of Class 3 Antiarrhythmic drugs used in AF treatment?
- Sotalol (β blocker with additional Class 3 activity) 80mg bd
- Amiodarone 200 mg daily
Give an example of a multichannel blocking Antiarrhythmic drugs used in AF treatment?
Dronedarone 400 mg bd
What are Antiarrhythmic drugs usually used in combination with for AF treatment?
Beta blocker
What is catheter ablation used for?
Identification of triggers for paroxysmal AF in the pulmonary veins
Describe the outcomes of Pulmonary vein isolation in paroxysmal/persistent AF?
- Paroxysmal: curative in up to 65-80%
- Persistent: 50-60% curative
What are the 2 different types of catheter ablation?
- Radiofrequency current (“burning”)
2. Cryo-ablation (“freezing”)
What are the 2 types of AF patients that should be considered for referral to an arrhythmia specialist for consideration of ablation according to SIGN?
- Highly symptomatic paroxysmal AF resistant to 1+ antiarrhythmic drugs & little/no comorbidity
- Symptomatic AF (paroxysmal/persistent), symptomatic HF & left ventricular systolic dysfunction with a left ventricular ejection fraction of 25–35%
What should Catheter ablation techniques for atrial fibrillation focus on according to SIGN?
Electrical isolation of the pulmonary veins
What should be considered for highly symptomatic patients with little or no comorbidity according to SIGN?
An early ablation strategy
What should patients who present with typical atrial flutter be offered according to SIGN?
Radiofrequency catheter ablation
