Cardiomyopathy, pericardial disease and congenital heart disease

Question 1

Acute myocarditis - causes

Answer 1

Inflammation of the myocardium.

Causes – idiopathic (50%), viral (flu, hepatitis, mumps, rubeola, Coxsackie, polio, HIV), bacterial (clostridia, diphtheria, TB, meningococcus, mycoplasma, brucellosis, psittacosis), spirochaetes (leptospirosis, syphilis or Lyme), protozoa, drugs (cyclophosphamide), toxins or vasculitis.

Question 2

Acute myocarditis - clinical features

Answer 2

Fatigue, dyspnoea, chest pain, fever, palpitations, tachycardia or S4 gallop.

Question 3

Acute myocarditis - investigation and management

Answer 3

• Investigations – ECG (for ST elevation or depression, T wave inversion, atrial arrhythmias or transient AV block) and positive troponin I or T can confirm the diagnosis.
• Management – supportive – patients may fully recover or have intractable heart failure.

Question 4

Dilated cardiomyopathy - causes

Answer 4

A dilated heart of unknown cause.

Causes - congenital or associated with alcohol, hypertension, haemochromatosis, viral infection, autoimmune, peri or postpartum or thyrotoxicosis.

Question 5

Dilated cardiomyopathy - clinical features

Answer 5

• Symptoms – presents with fatigue, dyspnoea, pulmonary oedema, right ventricular failure, emboli, atrial fibrillation or ventricular tachycardia.
• Signs – hypotension, tachycardia, raised JVP, displaced and diffuse apex beat, S3 gallop rhythm, mitral or tricuspid regurgitation, pleural effusion, oedema, jaundice, hepatomegaly or ascites.

Question 6

Dilated cardiomyopathy - investigation and management

Answer 6

• Investigations - bloods (plasma BNP is sensitive and specific and hyponatraemia indicates a poor prognosis), CXR (cardiomegaly or pulmonary oedema), ECG (tachycardia and T wave changes) and Echo (globally dilated hypokinetic heart with a low ejection fraction).
• Management – bed rest, diuretics, digoxin, ACEi, anticoagulation, biventricular pacing or ICD.

Question 7

Hypertrophic cardiomyopathy - definition and clinical features

Answer 7

Asymmetric septal hypertrophy leads to left ventricular outflow tract obstruction (LVOT). HCM is the leading cause of sudden death in young patients.

• Prevalence – 0.2% are transmitted by autosomal dominant inheritance but 50% are sporadic. 70% have mutations in genes encoding β-myosin, α-tropomysin and troponin T.

Question 8

Hypertrophic cardiomyopathy - clinical features

Answer 8

• Symptoms – sudden death is the first presentation in many patients but can also present with angina, dyspnoea, palpitations, syncope and congestive cardiac failure.
• Signs – jerky pulse, double apex beat, thrill at left sternal edge and harsh ejection systolic murmur.

Question 9

Hypertrophic cardiomyopathy - investigations

Answer 9

• ECG – left ventricular hypertrophy, progressive T wave inversion, deep Q waves, atrial fibrillation, WPW syndrome, ventricular ectopics or ventricular tachycardia.
• Echo – asymmetrical septal hypertrophy, small LV cavity with hyper-contractile posterior wall, mid-systolic closure of aortic valve or systolic movement of mitral valve.
• Cardiac catheterisation – to assess severity of gradient, coronary artery disease or MR.

Question 10

HCM - management and prognosis

Answer 10

• Management – β blockers or verapamil to control the symptoms (by reducing ventricular contractility) and amiodarone to control arrhythmias (e.g. AF or VT). Anticoagulate these patients for paroxysmal AF or systemic emboli. A septal myomectomy (surgical or chemical – with alcohol) to decrease outflow tract gradient is reserved for those with severe symptoms.
• Prognosis – mortality rate is 6% per year when <14 years and 2.5% per year when >14 years.

Question 11

Restrictive cardiomyopathy

Answer 11

Causes – idiopathic, amyloidosis, haemochromatosis, sarcoidosis or scleroderma. It presents like constrictive pericarditis with features of right ventricular failure – raised JVP with prominent x and y descents, hepatomegaly, ascites and oedema Treat the cause!

Question 12

Cardiac myxoma

Answer 12

A rare benign cardiac tumour with a prevalence of <5 per 10,000 – usually sporadic but can also be familial. It may mimic infective endocarditis – fever, weight loss, clubbing and raised ESR or mitral stenosis – LA obstruction, systemic emboli or atrial fibrillation. Treatment is excision.

Question 13

Acute pericarditis - causes

Answer 13

There is inflammation of the pericardium.

Can be idiopathic or secondary to viruses (Coxsackie, influenza, Epstein-Barr, mumps, varicella or HIV), bacteria (pneumonia, rheumatic fever, TB, staphylococcus, streptococcus), fungi, MI, Dressler’s syndrome, drugs (procainamide, hydralazine, penicillin or isoniazid), uraemia, RA, SLE, myxoedema, trauma, surgery, malignancy, radiotherapy or sarcoidosis.

Question 14

Acute pericarditis - clinical features

Answer 14

Central chest pain that is worse on inspiration or lying flat and relieved on sitting forward, pericardial friction rub, there may be a pericardial effusion or tamponade.

Question 15

Acute pericarditis - investigations

Answer 15

ECG shows concave saddle shaped ST elevation or may be normal in 10%, bloods – FBC, ESR, Us and Es, cardiac enzymes (troponin may be raised), viral serology, blood cultures and CXR may show cardiomegaly indicating a pericardial effusion or an Echo.

Question 16

Acute pericarditis - management

Answer 16

Analgesia e.g. 400mg Ibruprofen TDS and treat the underlying cause. Consider Colchicine before giving steroids or immunosuppressants (can increase risk of reoccurrence).

Question 17

Pericardial effusion - definition and features

Answer 17

There is accumulation of fluid in the pericardial sac – same causes as pericarditis.

• Clinical features – dyspnoea, raised JVP, Ewart’s sign (bronchial breathing at the left lower base due to a large effusion compressing the left lower lobe) and look for cardiac tamponade.

Question 18

Pericardial effusion - diagnosis and management

Answer 18

• Diagnosis – CXR shows an enlarged globular heart, ECG shows low voltage QRS complexes and alternating QRS morphologies and Echo shows an echo free zone surrounding the heart.
• Management – treat underlying cause – pericardiocentesis may be diagnostic in infection or therapeutic in tamponade. Send pericardial fluids for culture, ZN stain/TB culture and cytology.

Question 19

Constrictive pericarditis

Answer 19

The heart is encased in a rigid pericardium.

• Causes – often unknown in the UK but elsewhere usually TB and can follow any pericarditis.
• Clinical features – mainly of right sided heart failure – raised JVP, Kussmaul’s sign (JVP rises with inspiration), a soft and diffuse apex beat, quiet heart sounds, added S3, diastolic pericardial knock, hepatomegaly, splenomegaly, ascites and peripheral oedema.
• Investigations – CXR – small heart ± cardiac calcification.
• Management – surgical excision.

Question 20

Cardiac tamponade - causes and signs

Answer 20

Fluid raises intra-pericardial pressure, hence poor ventricular filling and fall in CO.

• Causes – pericarditis, aortic dissection, haemodialysis, warfarin or septal puncture after biopsy.
• Signs – hypotension, tachycardia, pulses paradoxus, raised JVP, Kussmauls sign and quiet S1/S2.

Question 21

Cardiac tamponade - diagnosis and management

Answer 21

• Diagnosis – Beck’s triad – hypotension, raised JVP and a small, quiet heart, CXR - large heart, ECG – low voltage QRS, Echo – diagnostic – echo free zone around heart and RA/RV collapse.
• Management – effusion needs urgent drainage – send fluid for culture, ZN stain and cytology.

Question 22

Bicuspid aortic valve

Answer 22

These work well at birth and go undetected. Many eventually develop aortic stenosis needing valve replacement ± aortic regurgitation predisposing to infective endocarditis ± aortic dilation or dissection. Intense exercise may accelerate complications so do yearly echocardiograms.

Question 23

Atrial septal defect - types

Answer 23

Ostium secundum - defects high in the septum are commonest and are often asymptomatic until adulthood as the left to right shunt depends on compliance of the left and ventricles. Left ventricular function decreases with age augmenting the left to right shunt leading to dyspnoea and heart failure at age 40-60 years. There may be pulmonary hypertension, cyanosis, arrhythmias, haemoptysis and chest pain.

Ostium primum are lower in the septum, are associated with atrioventricular valve abnormalities and present early.

Question 24

ASD - signs and complications

Answer 24

• Signs – atrial fibrillation, fixed split S2, pulmonary ejection systolic murmur and a raised JVP. Pulmonary hypertension may eventually lead to pulmonary or tricuspid regurgitation.
• Complications – reversal of left to right shunt = Eisenmenger’s complex – initial left to right shunt lead to pulmonary hypertension and shunt reversal, cyanosis and heart failure. Paradoxical emboli can occur – venous emboli pass through ASD into the arterial circulation.

Question 25

ASD - investigations

Answer 25

ECG – RBBB with left axis deviation and prolonged PR interval in a primum defect or right axis deviation in a secundum defect. CXR – small aortic knuckle, pulmonary plethora or progressive atrial enlargement. An echocardiogram is diagnostic. Cardiac catheterisation – shows step up in O2 saturation in right atrium (due to blood from the LA).

Question 26

ASD - management

Answer 26

Transcatheter closure is recommended in children before the age of 10 years and in adults who are symptomatic or if pulmonary to systemic blood flow ratio is >1.5:1.

Question 27

VSD - causes and complications

Answer 27

• Causes - congenital – prevalence is 2 in 1000 or acquired e.g. following myocardial infarction.
• Complications – aortic regurgitation, infundibular pulmonary stenosis, infective endocarditis, pulmonary hypertension or Eisenmenger’s complex – shunt reversal.

Question 28

VSD - investigations

Answer 28

ECG – normal in small VSD, left axis deviation and LV hypertrophy in moderate VSD or LV and RV hypertrophy in severe VSD. CXR – normal heart size ± mild pulmonary plethora in small VSD or cardiomegaly, large pulmonary arteries and marked pulmonary plethora in a large VSD. Cardiac catheterisation – high oxygen saturation in the right ventricle.

Question 29

VSD - management

Answer 29

Medical at first as it may close spontaneously.

Indications for surgery include – failed medical therapy, symptomatic VSD, shunt ratio 3:1 or infective endocarditis.

Question 30

Coarctation - definition and associations

Answer 30

Congenital narrowing of the descending aorta usually occurs just distal to the origin of the left subclavian artery and is more common in boys. Associations – bicuspid aortic valve or Turner’s syndrome.

Question 31

Coarctation - signs and complications

Answer 31

• Signs – radio-femoral delay, weak femoral pulse, hypertension, scapular bruit or systolic murmur (best heard over the left scapula).
• Complications – heart failure or infective endocarditis.

Question 32

Coarctation - investigation and management

Answer 32

• Investigations – CT or MRI aortogram and CXR showing rib notching.
• Management – either surgery or balloon dilation ± stenting.

Question 33

Tetralogy of Fallot

Answer 33

The most common cyanotic congenital heart disorder thought to be caused by failure of the truncus arteriosus to separate into the aorta and pulmonary arteries. There are 4 typical features – ventricular septal defect, pulmonary stenosis, RV hypertrophy and an overriding aorta.