Cardiology 2 Flashcards
What is atrial fibrillation?
The most common sustained cardiac arrhythmia
Characterised by irregularly irregular ventricular pulse and loss of association between the cardiac apex beat and radial pulsation
What are the adverse effects of the loss of active ventricular filling in AF?
Stagnation of blood in the atria –> thrombus formation
Reduced cardiac output may lead to heart failure
What are the types of AF?
Acute: onset within 48h Paroxysmal: spontaneous termination Recurrent: 2+ episodes Persistent: not self terminating but successful cardioversion Permanent: resistant to cardioversion
What is the aetiology of AF?
11% idiopathic Coronary/valvular heart disease Hyperthyroidism Diabetes Lung cancer Excess caffeine and alcohol
How does symptomatic AF present?
Dyspnoea Palpitations Syncope/dizziness Chest pain Stroke or TIA
What are the signs of AF?
S3 heart sound
Irregularly irregular pulse
What is seen on ECG in AF?
Variability in R-R intervals
No P waves
What other investigations are important in AF?
24h ambulatory ECG
Bloods: TFTs, FBC, biochem, electrolytes esp K, coagulation screen (pre warfarin)
CXR for structural causes
Baseline TTE
What are the indications for urgent admission in AF?
Pulse >150BPM or systolic BP<90mmHg
Loss of consciousness, severe dizziness, ongoing chest pain, progressive dyspnoea
What is the treatment of acute AF with and without haemodynamic instability?
With: emergency electrical cardioversion
Without: Electrical cardioversion or pharmacological cardioversion (flecainide or amiodarone)
In which patients is rhythm control preferred to rate control in AF?
AF has a reversible cause
HF is present and caused by AF
New onset AF
Rate control= >65 years, history of ischaemic HD
What is the first line monotherapy rate control in AF, and the contraindications?
Atenolol/bisoprolol (CI: COPD, asthma, bradycardia, heart block)
Diltiazem/verapamil (CI: heart failure)
What is the second line rate control treatment of AF?
Combine two medications: a beta blocker, diltiazem, digoxin)
Why should sotalol be avoided in AF?
Long QT Syndrome and toursades des pointes risk
Detail rhythm control of AF.
Electrical cardioversion with amiodarone before and after
OR
Drug treatment: amiodarone (if structural heart disease) or flecainide/amiodarone (if no structural heart disease)
What is the treatment of AF if drug treatment has failed to control symptoms?
Left atrial/AVN ablation and/or pacing
Which score assesses stroke risk in AF patients?
CHA2DS2VASc
Which score assesses risk of bleeding in patients on anticoagulation?
HAS-BLED
What is the thromboprophylaxis treatment of AF?
Warfarin or a NOAC.
What are the main subtypes of heart block?
AV block: block in the AV node or bundle of His
Bundle branch block: block lower down.
What does the Bundle of His split into?
Left bundle branch (which has anterior and posterior divisions) and right bundle branch
What is shown on an ECG in complete bundle branch blocks (left or right)?
Wide QRS (>0.12s), normal axis
RBBB: RSR in V1 (M) and W in V6 (marrow)
LBBB: septal depolarization is reversed so change in initial direction of QRS (William).
What are the pathological effects of complete bundle branch blocks?
LBBB: late activation of the left ventricle
RBBB: late activation of the right ventricle
What is a hemiblock?
Block in the separate divisions of the left bundle produces a swing of depolarization (electrical axis)
What is seen in left anterior hemiblock, and left posterior hemiblock?
LA: left axis deviation, Q waves in I and aVL, small R in III
LP: right axis deviation, small R in I, small Q in III
What is first degree AV block?
Prolongation of PR interval >0.2s
Every atrial depolarization conducts to ventricles but it is delayed
What are the types of 2nd degree AV block?
Mobitz type I
Mobitz type II (2:1 or 3:1)
What is Mobitz type I heart block?
Progressive lengthening of the PR interval with eventual dropped ventricular contraction
How long is the QRS complex in Mobitz type II block?
> 0.12s
Where is the blockage in Mobitz type II block?
Bundle of His
What has occurred when there is complete dissociation between the atria and ventricles?
3rd degree AV block
What are five causes of heart block?
Acute MI SLE Endocarditis Cardiomyopathy Hypokalaemia/hypomagnesaemia
How is heart block treated?
Pacemaker
Acute bradycardia: atropine, isoprenaline/adrenaline, temporary pacing
What occurs in preserved ejection fraction heart failure?
Impaired LV relaxation - diastolic, normal LV ejection fraction
Define reduced ejection fraction heart failure, and what it leads to.
Ejection fraction below 40%
Impaired contraction –> reduced cardiac output
Give three causes of high output heart failure?
Anaemia
Paget’s disease
Hyperthyroidism
Low output heart failure is where output is decreased and fails to increase with exertion. Give the three types and an example.
Chronic excessive afterload: AS/HTN
Excessive preload: MR/fluid overload
Pump failure: systolic/diastolic failure, anti-arrhythmics are negatively ionotropic
How does acute heart failure present?
Pulmonary or peripheral oedema without peripheral hypoperfusion
Give five signs and symptoms of left ventricular failure.
Dyspnoea/PND/orthopnoea Poor exercise tolerance Fatigue Wheeze Nocturnal cough with pink frothy sputum
Give five signs and symptoms of right ventricular failure.
Peripheral oedema Ascites Pulsation in neck and face from tricuspid regurgitation Nausea and anorexia RV heave from PHTN
How is heart failure initially investigated?
ECG and BNP
If any abnormalities, then echo and/or CXR
What is seen on CXR in heart failure?
Alveolar oedema Kerley B lines (interstitial oedema) Cardiomegaly Dilated prominent upper lobe vessels Pleural Effusion
What criteria is used to diagnose congestive heart failure?
Framingham criteria
What is the New York classification of heart failure?
- No dyspnoea but heart disease present
- Comfortable at rest, dyspnoea on ordinary activities
- Less than ordinary activity causes dyspnoea, which is limiting
- Dyspnoea present at rest
Why should alcohol be reduced in managing heart failure?
Can act as a negative inotrope, increases BP and risk of arrhythmias
What is the treatment of preserved ejection fraction heart failure?
Loop diuretic
Any other treatment of CV disease
What is the three step treatment of reduced ejection fraction heart failure?
1) ACEI and BB
2) Aldosterone antagonist/ARB/hydralazine AND nitrate
3) Digoxin/Ivabradine
Loop diuretic for fluid overload
Which drugs should be avoided in heart failure?
Verapamil, diltiazem, short acting dihydropyridine agents
Which additional drug can be used in heart failure and when?
Sacubitril valsartan
For patients who are symptomatic on ACEIs or ARBs
What is included in the acute coronary syndrome?
Unstable angina
NSTEMI
STEMI
Name some non-modifiable risk factors for ACS.
Male FH of premature CHD Premature menopause Ethnicity: S.Asian Increasing age
What symptoms is ACS chest pain associated with?
Sweating
Nausea
Dyspnoea
Palpitations
How might atypical ACS present?
Women and elderly
Abdo discomfort or jaw pain
What are three signs of ACS?
Low grade fever
Hypo or hypertension
S3 and S4
Signs of CCF
What is seen on ECG in ACS?
New ST segment elevation
Initially peaked T waves then T wave inversion
New Q waves
What is seen on ECG in myocardial ischaemia?
ST depression
What other investigations are important in ACS?
FBC, potassium, magnesium, eGFR, lipid profile, CRP Cardiac troponins T and I Myocardial creatine kinase CXR and Echo Pulse oximetry and blood gases Cardiac angiography
What is the pre-hospital or initial management of ACS?
Oxygen
SL glycerol trinitrate
IV morphine
300mg Aspirin
How is reperfusion achieved in STEMIs or NSTEMIs?
Primary PCI is superior to fibrinolysis
Before, give aspirin, ticagrelor, and unfractionated/LMW heparin
If not suitable, then fibrinolysis
What is the treatment of patients post-MI?
Clopidogrel and aspirin Beta blocker ACEI Statin Eplerenone if signs of HF
What is the gold standard diagnosis of Prinzmetal’s angina?
Coronary angiography with provocative tests (ergonovine/acetylcholine/dopamine)
Define postural hypotension.
Drop in BP>20/10mmHg within three minutes of standing
Why does postural hypotension occur?
Normal pooling of the blood in the lower limbs is not correctly regulated by the CV system when moving to a vertical position
Give five causes of postural hypotension
Multi-system atrophy Pregnancy Diuretics/vasodilators Aortic stenosis/AF Heart failure
When do you refer to cardiology in postural hypotension?
If the ECG is abnormal, or heart disease is suspected
What self measures can be taken to improve postural hypotension?
Stand up slowly and dorsiflex the feet first
Cross legs whilst upright
Raise head of the bed
Morning caffeine
What is the first line management of postural hypotension?
Increase intravascular fluid volume with large daily salt intake until weight has increased by 1.3-2.3kg
What is second line management of postural hypotension?
Fludrocortisone 0.1-0.2mg/day
Still requires high salt diet and adequate fluid intake
What is the main consequence of renal artery stenosis?
Renal hypoperfusion leads to hyperactivation of the renin-angiotensin-aldosterone axis, causing hypertension
Give three causes of renal artery stenosis.
Atherosclerosis
Takayasu’s arteritis
Fibromuscular dysplasia of the renal artery - string of beads appearance on MR angiography
Describe the hypertension of renal artery stenosis.
Abrupt onset and severe
Resistant to standard medical therapy
With hypokalaemia
How else may renal artery stenosis present?
Decompensatoin of CCF in an already hypertensive patients e.g. flash pulmonary oedema
What is the main finding of renal artery stenosis on examination?
Systolic-diastolic bruit heard over the flank
How is RAS diagnosed?
U&Es, glucose, lipids
24h urinary protein excretion, presence of RBC
Duplex renal USS and Doppler
CT/MR angiography
How is RAS managed?
Avoid ACEIs, ARBs, and other nephrotoxic drugs
Angioplasty with stenting
Where are the most common locations for peripheral vascular disease?
Subclavian artery
Brachiocephalic trunk
Give five possible symptoms of PVD.
Intermittent claudication Critical limb ischaemia Skin ulceration Paraesthesiae and coldness Hair loss
How is PVD diagnosed?
BP both arms difference>15mmHg
Duplex USS
Palpation of pulses
ABPI
What are the different scores of the Ankle-brachial pressure index?
Normal=1
Claudication=0.6-0.9
Rest pain=0.3-0.6
Impending gangrene=0.3 or less
How is PVD treated?
Antiplatelets
Peripheral vasodilators such as naftidrofuryl oxalate
Endovascular surgery
What is ventricular tachycardia?
A broad complex tachycardia originating from a ventricular ectopic focus
Defined as 3+ ventricular extrasystoles in succession at a rate of more than 120BPM
What are the types of VT?
Fascicular
Right ventricular outflow tract
Toursades des pointes
Polymorphic ventricular tachycardia
What is the cause of VT?
Coronary and structural disease
Low K, Mg, Ca
Caffeine or cocaine
How does VT present?
Symptoms of ischaemic heart disease, or haemodynamic compromise from poor perfusion
What is seen on ECG in VT?
Rate 150-200BPM
Wide QRS complexes>120ms
AV dissociation
Fusion beats
What is the treatment of pulseless VT?
Treated as for VF (CPR, assessment of rhythm, unsynchronised defibrillation)
Post cardiac arrest treatment: ABCDE approach SpO2 94-98% 12-lead ECG Treat cause and control temp
What is the treatment of unstable VT with reduced cardiac output?
Synchronised cardioversion
Advanced cardiac life support
What is the treatment of haemodynamically stable VT?
IV 300mg Amiodarone/IV Lidocaine
2nd line cardioversion
If poor left ventricular dysfunction, then amiodarone
How is VT prevented against in patients with a history?
Implantable cardioverter defibrillator
What are the types of SVTs?
AV nodal re-entry tachycardia
AV re-entry tachycardia
Atrial tachycardia
What are some causes of SVTs?
Accessory bypass pathways e.g. WPW is most well known type of AVRT
Fast conducting and slow conducting pathways
Abnormalities of impulse conduction
What is seen on ECG during an attack of SVT?
P waves may not be visible
Short PR<0.12s and delta wave - WPW pattern, evidence of pre-excitation
What is the treatment of haemodynamically unstable SVT?
DC cardioversion
What is the treatment of haemodynamically stable SVT?
Vagal manoeuvres e.g. carotid massage or Valsalva
IV adenosine
Cardioversion 3rd line
What is the function of adenosine and are there any contraindications?
Blocks conduction through the AV node
CI: severe asthma
What is the ongoing management of SVT?
Radiofrequency ablation of the slow/accessory pathway
Rate limiting CCB, flecainide
What are the symptoms of aortic stenosis?
Asymptomatic even if moderate (but still susceptible to SCD)
Dyspnoea on exertion, angina, syncope
What are the signs of AS?
Pulsus parvus et tardus
Narrow pulse pressure
Crescendo-decrescendo systolic ejection murmur loudest at apex, 2nd IC space, radiation to carotids
What is the gold standard diagnosis of valvular disease?
Echo with Doppler
What is the treatment of AS?
Treat any HF
Aortic valve replacement
What are the complications of calcific cardiac valves?
Infective endocarditis
Small systemic emboli
What are the causes of aortic regurgitation?
Rheumatic heart disease
Bicuspid aortic valve
SLE
What is the AR murmur?
Early diastolic murmur heard best in the aortic area, with the patient sitting forward and in expiration
What is the treatment of AR?
Vasodilators and inotropic agents prior to aortic valve replacement
What are the effects of mitral stenosis?
Increased left atrial and pulmonary arterial pressure, which leads to RV dilation and tricuspid regurgitation
What are three causes of mitral stenosis?
Rheumatic fever
Degenerative calcification
Lutembacher’s syndrome
How does mitral stenosis present?
AF, progressive dyspnoea, palpitations, haemoptysis
Malar flush, raised JVP, signs of RV failure
Mid-late diastolic murmur, best heard in left lateral position with bell
What is the treatment of mitral stenosis?
Percutaneous mitral commissurotomy (balloon valvuloplasty)
What is the murmur of mitral regurgitation?
Pansystolic murmur at the apex
Which patients are at risk of having a silent MI?
Elderly
Diabetic
When are Q waves pathological?
> 40ms (1mm) wide
2mm deep
Seen in leads V1-V3
What are the symptoms of neutrally mediated (reflex) syncope?
Prodrome of sweating, pallor, nausea and vomiting
Transient loss of consciousness
What is seen on ECG in hypothermia?
J waves - notch in the downward portion of the R wave in QRS complex
Which beta blockers can be used in heart failure?
Bisoprolol
Carvedilol
Nebivolol
What is stage 1 hypertension?
Clinic reading of 140/90 AND home reading of 135/85
What is stage 2 hypertension?
Clinic reading of 160/100 AND home reading of 150/95
When should stage 1 hypertension be treated?
Age under 80 and:
- Q risk over 10%
- diabetes/renal/CV disease
- Target end organ damage
Outline the management of hypertension for patients aged under 55 or type 2 diabetics.
1) ACEI/ARB
2) ACEI/ARB + CCB/thiazide like diuretic
3) ACEI/ARB + CCB + thiazide like diuretic
4) If K+ <=4.5, low dose spironolactone; if K+ >4.5, alpha or beta blocker
What is the difference in management in Afro Caribbean patients or patients aged over 55 at presentation?
First step is a CCB
