CVS Flashcards
define pre-load and after-load
pre-load = volume in ventricle at end of diastole
after-load = total peripheral resistance
what is Frank-Starling’s law?
more ventricular distension during diastole = greater volume ejected during systoe
How would you calculate the heart rate from an ECG strip?
Each strip is 10 seconds long
Count the amount of QRS and then multiply by 6
What lead is normally the most positive? What would be the most positive in LBBB and RBBB respectively?
Lead II is normally the most positive
LBBB - Lead aVL
RBBB- Lead III
State the normal parameters for the PR interval, the QRS interval and the QT interval
PR - 120-200ms QRS - <120ms QT - 2 large squares
RBBB can be present without heart disease, however name three common causes of LBBB
- Anterior MI
- Congestive Heart Failure
- Left Ventricular Hypertrophy
Describe the diagnostic features of a STEMI
- Cardiac Chest Pain
- ECG changes (persistent ST elevation or new LBBB)
- Raised Troponin I (greater than 100 nanograms)
What are the parameters for ECG changes in a STEMI?
ST elevation in atleast 2 leads
Elevation greater than 1mm in limb leads and 2mm in chest leads
Describe the ECG changes in an NSTEMI
may show: ST segment depression T wave inversion Normal
When might an STEMI be mistaken for an NSTEMI?
If you have ST segment depression in V1-V4, it may be the reciprocal changes of a posterior STEMI
Describe the pathophysiology of ACS
- Plaque rupture
- Thrombosis to varying degrees
- Inflammation
- Artery occlusion and reduced blood supply to myocardium
What layer of the heart do the coronary arteries lie in?
Epicardium
Describe 5 of the classical presentations of ACS
- Central crushing chest pain lasting >20 mins
- Nausea
- Sweating
- Breathlessness
- Palpitations
Some ACS can be ‘Silent’, what groups of people can this occur in? How would they present?
- Elderly and Diabetics
- Syncope, Epigastric Pain
What is the S4 heart sound?
Blood striking against a non compliant ventricle
What happens to Troponin I in an MI
Begin to rise 3-4hrs post MI Remain elevated for up to 2 weeks
what level of hs-TnI is highly likely of myocardial necrosis in men and women?
34 in men
16 in women
When should Troponin I be sampled?
One sample on admission If onset of the symptoms was less than 3 hours ago, take another sample one hour after the original
Give 4 false positives of Troponin I
- Advanced renal failure
- Large PE
- Severe CCF
- Aortic Dissection
- sepsis
- stroke
- cardiomyopathy
- malignancy
Give 3 possible features of an MI on a CXR
- Cardiomegaly
- Pulmonary Oedema
- Widened Mediastinum
In four steps describe the initial medical management of suspected ACS
1) Morphine and Antiemetic (Metacloperamide)
2) Oxygen (Sats>94% or <88% if COPD)
3) Nitrates (GTN Spray)
4) Asparin 300mg Loading Dose
What are the four requirements for Prasugrel in an MI?
- Undergoing PCI
- Less than 75 y/o
- Weight >60kg
- No prior TIA/Stroke
non-pharmacological management long term post MI (other than the 5 drugs what else can be done?
- Cardiac Rehab
- Cut out smoking
- Diet and Alcohol,
- DVLA advice (able to drive after one week, if a bus/lorry driver can’t for 6 weeks)
- ?Dyspepsia (provide PPI with Asparin)
what are the 5 drugs patients must have following an MI?
- Aspirin
- ACEi - Ramipril
- B-blocker - Bisoprolol
- Statin - Atrovostatin
- ADP- receptor antagonist - ticagrelor
Describe the management of NSTEMI
- Pain relief
- Aspirin 300mg
- LMWH
- Repeat ECG
- Risk assessment of patient with elevated hs-Tnl - grace score
- Ticagrelor if risk >3%
- Anti-anginals - nitrates
What is the Grace Score?
Used on ACS patients to estimate their inpatient and 3 year mortality
Describe the complications of an MI
- DARTH VADER
- Dresler syndrome - pericarditis post MI
- Arrhythmias
- Rupture of heart
- Tamponnade
- HF
- Valve complications
- Aneurysm of ventricle
- Death
- Emboli
- Recurrence
Name four STEMI mimics on ECG
- Early repolarisation in young & fit
- Pericarditis (saddle shaped)
- Brugada Syndrome (Sodium Channelopathy)
- Takotsubo Cardiomyopathy (temporary and brought on by stress - broken heart syndrome)
what is significant about an ECG showing ST depression in leads V1-V4 and what should be done?
may be a true STEMI in posterior aspect of heart so should be treated as a STEMI and should have posterior leads done - V7-9 as well as Right ventricular lead
what is ST elevation in RV4 highly sensitive for?
right ventricular infarction
What is stable angina?
Chest discomfort provoked by effort/emotion and relieved by rest
Describe four potential symptoms of Stable Angina
- Chest Pain
- Throat tightness
- Arm Heaviness
- Exertional Breathlessness
What features would make Angina unlikely?
Continuous/Very prolonged pain
Unrelated to activity level
Associated with other symptoms such as dizziness/dysphagia
Describe two methods of functional imaging
Stress Echo
Cardiac MRI
Describe pharmacological managements of Stable Angina
- Immediate - GTN spray
- Prevent symptoms - B-blocker, CCB, nitrates
- Secondary prevention - AAAA
- Aspirin, ACEi, Atorvostation, Atenelol (Bblocker)
When would you prescribe Ivabradine?
As an alternative to a Beta Blocker, for example if the patient is Hypotensive
When would you prescribe Ranolazine in Stable Angina?
- If intolerant to all the other drugs
- Commenced by consultants
- eGFR>30 (reduces sodium and hence calcium - relaxes muscle)
Other than Stable/Unstable, describe two other types of Angina
- Decubitus Angina - precipitated by lying flat
- Vasospastic Angina - spasm of coronary artery
How would you educate a patient in how to use GTN spray in Stable Angina?
- Repeat dose after 5 minutes if required If still persisting after 5 minutes of the second dose, call an ambulance
- SE: Headache, Hypotension
Describe the classes of HTN in terms of clinic readings
- Class 1 - 140/90
- Class 2 - 160/100
- Severe - 180/110
Describe the classes of HTN in terms of home readings
- Class 1 - 135/85
- Class 2 - 150/95
what is essential hypertension?
- accounts for 95% of hypertension
- aka primary hypertension
- hypertension has developed on its own and does not have a secondary cause
Give 4 broad causes of Secondary HTN
- Renal (Renal Artery Stenosis, PCKD)
- Pregnancy
- Drugs (Steroids, COCP, Cocaine)
- Endocrine (Cushings, Conns)
- Obesity
- (ROPED)
what are some complications of hypertension?
- Ischaemic heart disease
- Cerebrovascular accident (i.e. stroke or haemorrhage)
- Hypertensive retinopathy
- Hypertensive nephropathy
- Heart failure
at what blood pressure should a patient be offered ambulatory monitoring?
>140/90
when should treatment be initiated for hypertension?
treat stage 1 if <80 and
- evidence of end organ damage
- cvd
- enal impairement
- DM
- 10-year risk >20%
treat all stage 2
What is Malignant Hypertension?
- Rapid rise in blood pressure to over 200/130, leading to vascular and organ damage
- Can causes bilateral retinal haemorrhages, headache, visual disturbances
How does Hypertension present?
Generally asymptomatic - may have headache
If sweating/palpitations - Phaeochromocytoma
If muscle tetany/weakness - Hyperaldosteronism
Describe 5 investigations (apart from BP) necessary for HTN
- Full range of bloods (inc cholesterol)
- Urinalysis (A:Cr, Protienuria, Haematuria)
- ECG
- Fundoscopy
- Cardiac Echo
You should aim to reduce blood pressure slowly in Hypertensive patients. What is the BP goal in treated patients?
- Normal <140/90
- Diabetic <130/80
non-pharmacological treatments for hypertension
wieght reduction
minimise salt intake
minimise alcohol
aerobic exercise
smoking cessation
Describe the four step (up) management of Hypertension
Describe the 3 classes of CCBs, an example of each and their actions
- Dihydropyridine - acts on peripheral vasculature (eg Amlodipine, Nifedipine)
- Phenylalkamine - acts on cardiac vasculature (eg Verapamil)
- Benzothiazepine - acts on cardiac and peripheral vasculature (eg Diltiazem)
Describe the difference between a Hypertensive Emergency and a Hypertensive Urgency
Emergency - High BP with critical illness (AKI,MI, Encephalopathy)
Urgency - High BP without critical illness at the moment, often accompanied by retinal damage
Describe the management of a Hypertensive EMERGENCY
Reduce diastolic to 110mmHg in 3-12hrs
Use IV Sodium Nitroprusside/Labetolol/GTN/Esmolol (acts in 30s)
Describe the management of a Hypertensive URGENCY
- Reduce diastolic to 100mmHg in 48-72hrs
- Usually use Nifedipine AND Amlodipine for 3 days and then continue Amlodipine alone
- some patients have ACEi and calcium antagonist
how does phaeochromocytoma present? (triad)
- episodic headache
- sweating
- tachycardia
(most wont have all 3)
how is a diagnosis of phaeochromocytoma made?
- measuments of urinary and plasma fractionated metanephrines and catecholamines
- 24 hour urine collection
- CT or MRI scan of abdomen and pelvis to detect adrenal tumours
- MIBG scan can detect tumours not detected by CT or MRI
how is a phaeochromocytoma managed?
- all patients should undergo resection
- hyptension control in meantime is combined alpha and beta adrenergic blockade
- phenoxybenzamine most commonly used
- BETA NEVER INITIATED BEFORE ALPHA
Heart Failure is when cardiac output fails to meet the body’s requirements. Using the mnemonic HEART MAy DIE, give some causes.
- Hypertension
- Embolism
- Anaemia
- Rheumatic fever
- Thyrotoxicosis
- MI
- Arrhythmia
- Diet
- Infection
- Endocarditis
what are the 2 categories of heart failure?
diastolic = (filling) ventricular volume/capacity for blood is reduced, too stiff or ventricular walls thick (HRpEF)
systolic - (contractility) cant pump with enough force, walls thin/fibrosed, chamber enlarged, abnormal or uncoordinated myocardial contraction (HFrEF)
Describe the features of SYSTOLIC Heart Failure
Inability of the heart to contract, EF<40% Caused by IHD/MI/Cardiomyopathies
Describe the features of DIASTOLIC Heart Failure
- Inability of the heart to relax, EF>50% (HFpEF)
- Caused by Ventricular Hypertrophy/Tamponade
Right Ventricular Failure is caused by LVF or Chronic Lung Disease, give 3 features
- Peripheral Oedema
- Ascites
- Facial Engorgement
State 3 causes of ACUTE Heart Failure
- Infections
- Anaphylaxis
- PE
Heart Failure can be Low Output or High Output, give some causes of High Output and what is it?
- IE High but not high enough Pregnancy, Hyperthyroidism, Anaemia
- heart has enlarged and becomes fragile
Describe the use of BNP
- BNP can be used to rule out Heart Failure if it is less than 100ng/l
- Not diagnostic as BNP can be raised by anything that causes chamber stress (AF etc)
Using the A-E mnemonic describe the 5 features of a CXR of Heart Failure
- A - Alveolar Oedema (Bat Wings)
- B - Kerley B Lines (Interstitial Oedema)
- C - Cardiomegaly
- D - Dilated Veins
- E - Effusions
Other than bloods and CXR, what is the gold standard for testing cardiac function?
Echocardiography
What is Cardiac MRI used for in the context of Heart Failure?
- Better at imaging the RV
- Good at assessing scar tissue
Give 5 features of Heart Failure
- Cyanosis
- Low BP
- Narrow Pulse Pressure
- Apex Displacement
- RV Heave
Describe the New York Classification of Heart Failure
- I - Heart Disease present but no limitations
- II - Comfortable at rest but dyspnoea in normal activities
- III - Less than ordinary activity causes dyspnoea
- IV - Dyspnoea at rest
There are many medications that can be given for Heart Failure, but what device could patients have fitted?
Cardiac Resynchronisation Therapy Adds pacing to septal and lateral walls will reduce QRS width Considered if signs of LBBB Can combine with Defib device
describe NICE management of HF
- Furosemide
- ACEi
- ARB
- Bblockers
physiological effects of betablockers in heart failure
- reduce HR
- reduce BP
- 1+2= reduced myocaridal oxygen demand
- reduce mobilisation of glycogen
- negate unwanted effects of catecholamines
whan is ivabradine used in heart failure?
- when pt cannot tolerate B blockers
- resting hr higher than 75 despite B blockers
- has no impact on blood pressure
when are vasodilators hydralazine and isosorbide mononitrate used in heart failure?
- in combination shown to be beneficial
- african or carribean patients
- if pt cannot take ARB or ACEi
- add to ACEi or ARB in resistant CCF
what is the benefit of using nitrates in HF
reduce preload, reduce pulmonary oedema, reduce ventricular size