Cardiology Flashcards
The chambers and the valves pump the sentiment around...
What dietary changes does NICE recommend to reduce risk of CVD? (%fat intake, frequency of food groups)
The NICE guidelines on cardiovascular disease (updated February 2023) recommend the following dietary changes:
Total fat is less than 30% of total calories (primarily monounsaturated and polyunsaturated fats)
Saturated fat is less than 7% of total calories
Reduced sugar intake
Wholegrain options
At least 5 a day of fruit and vegetables
At least 2 a week of fish (one being oily)
At least 4 a week of legumes, seeds and nuts
What dies NICE recommended in terms of exercise to reduce risk of CVD?
The NICE guidelines recommend (limited by co-morbidities):
Aerobic activity for a total of at least 150 minutes at moderate intensity or 75 minutes at vigorous intensity per week
Strength training activities at least 2 days a week
What is the difference between primary and secondary prevention in CVD?
Prevention of cardiovascular disease falls into two main categories:
Primary prevention for patients that have never had a diagnosis of cardiovascular disease.
Secondary prevention after a diagnosis of angina, myocardial infarction, TIA, stroke or peripheral arterial disease.
What does the QRISK score estimate?
The QRISK score estimates the percentage risk that a patient will have a stroke or myocardial infarction in the next 10 years.
What QRISK3 score does NICE recommend as the threshold to commence medication? What medication would be offered?
The NICE guidelines (updated February 2023) recommend when the result is above 10%, they should be offered a statin, initially atorvastatin 20mg at night.
When is atorvastatin offered to patients as primary prevention of CVD? (Give 3 circumstances)
- QRISK3 score >10%
- Chronic kidney disease (eGFR less than 60 ml/min/1.73 m2)
- Type 1 diabetes for more than 10 years or are over 40 years
What is the mechanism of action for statins?
Statins reduce cholesterol production in the liver by inhibiting HMG CoA reductase.
When does NICE recommend checking lipids after commencing statins? When should statin dose be increased?
NICE recommend checking lipids at 3 months after starting statins and increasing the dose to aim for a greater than 40% reduction in non-HDL cholesterol.
When does NICE recommend checking LFTs after starting statins and why?
NICE recommend checking LFTs within 3 months of starting a statin and again at 12 months. Statins can cause a transient and mild rise in ALT and AST in the first few weeks of use. They usually do not need to be stopped if the rise is less than 3 times the upper limit of normal.
Name some rare but significant side effects of statins.
- Myopathy (causing muscle weakness and pain)
- Rhabdomyolysis (muscle damage – check the creatine kinase in patients with muscle pain)
- Type 2 diabetes
- Haemorrhagic strokes (very rarely)
Which antibiotics interact with statins and would prompt withholding statins during the course?
Macrolide antibiotics e.g. clarithromycin, erythromycin
Name 2nd line cholesterol lowering drugs when statins are contraindicated.
Ezetimibe
PCSKg inhibitors (evolocumab, alirocumab)
Name the 4 A’s of secondary prevention in CVD
A – Antiplatelet medications (e.g., aspirin, clopidogrel and ticagrelor)
A – Atorvastatin 80mg
A – Atenolol (or an alternative beta blocker – commonly bisoprolol) titrated to the maximum tolerated dose
A – ACE inhibitor (commonly ramipril) titrated to the maximum tolerated dose
What medications are started after an MI? What is the duration?
After a myocardial infarction, patients are offered dual antiplatelet treatment initially, with:
- Aspirin 75mg daily (continued indefinitely)
- Clopidogrel or ticagrelor (generally for 12 months before stopping)
What is the inheritance pattern of familial hypercholesterolaemia?
autosomal dominant
What criteria can be used to make a clinical diagnosis of familial hypercholesterolaemia (2)? What level of serum cholesterol would be a sign?
Simon Broome criteria
Dutch Lipid Clinic Network Criteria
cholesterol of >7.5 mmol/L
What are the characteristics of stable angina?
Caused by exertion, relieved by rest or GTN spray
What investigation can be used to assess cardiac function?
Cardiac stress testing
What does cardiac stress testing involve?
Cardiac stress testing involves assessing the patient’s heart function during exertion. This can involve having the patient exercise (e.g., walking on a treadmill) or giving medication (e.g., dobutamine) to stress the heart. The options for assessing cardiac function during stress testing are an ECG, echocardiogram, MRI or a myocardial perfusion scan (nuclear medicine scan).
What investigations can be used to assess for coronary artery narrowing? Which is gold standard?
CT coronary angiography
Invasive coronary angiography (gold-standard)
What ECG changes may indicate ischaemia or previous MI?
- Pathological Q waves (in particular).
- Left bundle branch block (LBBB).
- ST-segment and T-wave abnormalities (for example T-wave flattening or elevation, or T-wave inversion).
What are the 1st line treatments for stable angina?
- GTN PRN - symptomatic relief
- Beta-blocker (e.g. bisoprolol) OR CCB (e.g. diltiazem or verapamil C/I in HFREF)
What are some side effects of GTN?
headaches and dizziness caused by vasodilation
What is a contraindication of CCBs?
HFREF
What are some 2nd line treatments for stable angina?
- Long-acting nitrates (e.g., isosorbide mononitrate)
- Ivabradine
- Nicorandil
- Ranolazine
How much fluid is in the pericardium?
less than 50 mls
List causes of pericarditis (7). What is the most common?
- Idiopathic (no underlying cause)
- Infection (e.g., tuberculosis, HIV, coxsackievirus, Epstein–Barr virus and other viruses)
- Autoimmune and inflammatory conditions (e.g., systemic lupus erythematosus and rheumatoid arthritis)
- Injury to the pericardium (e.g., after myocardial infarction, open heart surgery or trauma)
- Uraemia (raised urea) secondary to renal impairment
- Cancer
- Medications (e.g., methotrexate)
Which phase of the heart beat/function does pericardial effusion affect?
Diastole
Explain the process of the effect of pericardial tamponade on cardiac output.
Pericardial effusion => raised intra-pericardial pressure => reduced filling in diastole => lower cardiac output during systole => cardiac tamponade
Describe the chest pain in pericarditis.
Sharp, central/anterior, pleuritic (worse on inspo), orthopnoea (worse when lying down), improved on sitting forward
What sign can be elicited on auscultation in pericarditis?
Pericardial friction rub
What can be seen on a blood test in pericardial effusion
raised inflammatory markers
What can be seen on ECG in pericarditis?
Saddle-shaped ST elevation
PR depression
Diagnostic test for pericarditis?
Echo
Medical management of pericarditis?
NSAID (aspirin or ibuprofen)
Colchicine - longterm, 3 months, to reduce risk of recurrence
2nd line) steroids
Management of pericardial tamponade
Pericardiocentesis
Symptoms of pericarditis/cardiac tamponade
Pain - sharp, constant sternal pain relieved by sitting forward. Pain may radiate to the left shoulder and/or left arm and/or into the abdomen, and is worse when lying on the left side and on inspiration, swallowing, and coughing.
Fever
Cough
Arthralgia.
Cardiac tamponade may have associated breathlessness, dysphagia, cough, and hoarseness.
Signs of pericarditis
Auscultation - pericardial friction rub (high pitched scratching sound, best heard over the left sternal border during expiration).
Cardio exam - Signs of cardiac tamponade include pulsus paradoxus (decrease in palpable pulse and arterial systolic blood pressure of 10 mmHg on inspiration); and hypotension, muffled heart sounds, and jugular venous distention (Beck’s Triad).
What is cardiac output?
volume of blood ejected by the heart per minute
What is stroke volume?
volume of blood ejected during each beat
What is the formula for cardiac output and stroke volume
CO = SV x HR
How does left ventricular failure affect pulmonary circulation?
Blood is not flowing efficiently through the left side of the heart => backlog of blood in the left atrium, pulmonary veins and lungs => increased volume and pressure => pulmonary oedema
What is acute left ventricular failure caused by? What are the triggers?
Caused by decompensated chronic heart failure
Triggers:
- iatrogenic (e.g. aggressive IVI)
- MI
- arrhythmias
- sepsis
- hypertensive emergency
What is the typical presentation of acute LVF?
Acute shortness of breath, worse on lying flat, better with sitting up
- Type 1 respirator failure
- looking and feeling unwell
- cough with frothy white or pink sputum
What is the nature of the cough in pulmonary oedema?
Cough with frothy white or pink sputum
What are some signs on examination in LVF?
- raised RR
- reduced O2 sats
- inc HR
- 3rd heart sound
- b/l basal crackles
- hypotension in severe cases (cardiogenic shock)
What is BNP?
B-type natriuretic peptide is a hormone released from ventricles when myocardium is stretched beyond normal , suggesting heart is overloaded.
It relaxes smooth muscle in blood vessels, reducing systemic vascular resistance. It also acts as a diuretic
Describe the sensitivity and specificity of BNP
BNP is sensitive (rules out) but not specific (rule in)
What is a normal ejection fraction?
Above 50%
How is cardiomegaly classified on CXR?
> 0.5 of cardiothoracic ratio
What is the management of LVHF (hint: mnemonic)?
SODIUM
Sit up
Oxygen
Diuretics
IVI stopped
Underlying causes stop
Monitor fluid balance
What management can be started by a specialist in severe cases of LVHF?
- IV opioids = vasodilators
- IV nitrates = vasodilators
- Inotropes e.g. dobutamine = improve CO
- Vasopressors e.g. noradrenalin = improve BP
- NIV
- invasive ventilation
How do inotropes work?
alter heart contractility
Positive inotropes increase the contractility => inc CO and mean arterial pressure
How do vasopressors work?
cause vasoconstriction => inc systemic vascular resistance => inc MAP => inc BP => inc tissue perfusion
What follow up is required for NT-pro-BNP >2000ng/L?
Urgent specialist assessment and echo in 2 weeks
What follow up is required for NT-pro-BNP 400-2000ng/L?
specialist assessment and echo within 6 weeks
What is the management of HF with reduced EF
- Stop drugs that worsen HF
- Diuretic
- Offer ACE-i (exc valve disease) and B-b
What are symptoms of chronic heart failure?
- SOBOE
- cough
- Orthopnoea
- PND
- peripheral oedema
- fatigue
What are some signs of chronic heart failure?
- tachycardia/pnoea
- HTN
- murmur or 3rd heart sound
- b/l basal crackles
- raised JVP
- peripheral oedema
Describe the classifications in the New York Heart Association Classification (NYHA)
Class I: No limitation on activity
Class II: Comfortable at rest but symptomatic with ordinary activities
Class III: Comfortable at rest but symptomatic with any activity
Class IV: Symptomatic at rest
What is the 1st line medical treatment for chronic heart failure?
A – ACE inhibitor (e.g., ramipril) or ARB titrated as high as tolerated
B – Beta blocker (e.g., bisoprolol) titrated as high as tolerated
A – Aldosterone antagonist when symptoms are not controlled with A and B (e.g., spironolactone or eplerenone)
L – Loop diuretics (e.g., furosemide or bumetanide)
When is ACE-i contraindicated in chronic heart failure? What medication can be used instead?
If due to valvular heart disease. Use ARB instead (candesartan)
What are some causes of secondary hypertension?
ROPED
Renal artery stenosis
Obesity
Pre-eclampsia
Endocrine (Cushing’s, Conn’s, Phaeochromocytoma)
Drugs (alcohol, NSAIDs, oestrogen, liquorice)
What causes the 1st and 2nd heart sounds?
1st HS is caused by closure of the AV valves (tricuspid and mitral)
2nd HS is caused by closure of the semilunar valves (pulmonary and aortic)
What is the 4th heart sound?
heard directly before S1
always abnormal, rare
indicates stiff or hypertrophic ventricles
Describe how different valvular defects can affect chamber morphology?
When pushing against a stenotic valve, the muscle has to try harder, resulting in hypertrophy:
- Mitral stenosis causes left atrial hypertrophy
- Aortic stenosis causes left ventricular hypertrophy
When a leaky valve allows blood to flow back into a chamber, it stretches the muscle, resulting in dilatation:
- Mitral regurgitation causes left atrial dilatation
- Aortic regurgitation causes left ventricular dilatation
What murmur is caused by aortic stenosis? Where does it radiate?
Ejection systolic, high-pitched, crescendo-decrescendo. radiates to the carotids
What murmur is caused by aortic regurgitation?
early diastolic, soft murmur
Austin-Flint murmur - heard at the apex, “rumbling” sound