25. Acquired diseases of the heart and the pericardial sac

Acquired diseases of the heart and pericardial sac

Acquired valve disease includes stenosis and regurgitation of the aortic, mitral, tricuspid and pulmonary valves. Causes include degenerative calcification, rheumatic disease, infective endocarditis, congenital bicuspid valve and functional annular dilatation.
Aortic stenosis causes pressure overload and concentric left ventricular hypertrophy; symptoms classically include exertional dyspnoea, angina and syncope.
Mitral regurgitation causes left atrial and ventricular volume overload, with dyspnoea, fatigue and atrial fibrillation. Mitral stenosis commonly follows rheumatic disease and causes pulmonary venous hypertension, dyspnoea and atrial fibrillation.
Echocardiography assesses valve anatomy, severity, ventricular function and pulmonary pressure. Treatment ranges from surveillance and medical management to repair/replacement or transcatheter intervention.

Infective endocarditis is microbial infection of endocardial surfaces, usually valves. Risk factors include prosthetic valves, previous endocarditis, certain congenital lesions, intracardiac devices and injection drug use.
Features include fever, new or changing murmur, embolic phenomena, petechiae, splinter haemorrhages, glomerulonephritis and heart failure. Clinical signs may be subtle.
Obtain multiple sets of blood cultures before antibiotics if the patient is stable enough; perform transthoracic and often transoesophageal echocardiography. Use modified diagnostic criteria and investigate culture-negative causes when appropriate.
Treatment is prolonged IV antimicrobial therapy guided by cultures and susceptibility. Surgery is considered for heart failure due to valve dysfunction, uncontrolled infection/abscess, fungal or resistant infection, and selected embolic-risk situations.

Acute pericarditis causes sharp pleuritic chest pain improved by sitting forward, a pericardial friction rub and widespread ST elevation/PR depression on ECG. Causes include viral/idiopathic, post-MI, uraemia, autoimmune disease, malignancy and infection.
Treat uncomplicated inflammatory pericarditis with NSAID/aspirin plus colchicine when appropriate, with gastroprotection and activity restriction. Treat the underlying cause and avoid corticosteroids unless specifically indicated.
Pericardial effusion may be asymptomatic or cause tamponade. Echocardiography assesses size and haemodynamic effect. Tamponade requires urgent drainage and treatment of the cause.
Constrictive pericarditis causes impaired diastolic filling, systemic venous congestion, oedema, ascites and raised JVP. Diagnosis uses echocardiography, CT/MRI and sometimes catheterisation; pericardiectomy is considered for chronic symptomatic constriction.

Coronary artery disease may require CABG when anatomy, symptoms or prognostic indications favour surgery; optimise antiplatelet, lipid-lowering and risk-factor therapy.
Cardiac surgery decisions integrate symptoms, imaging, ventricular function, comorbidities, frailty and patient preference. Complications include bleeding, stroke, renal injury, infection, arrhythmia and graft/valve dysfunction.