Valvular heart diseases Year 4 Internal Medicine Notes

Valvular heart diseases Year 4 · Internal Medicine Collection: 4TH YEAR ALL NOTES / IMED / IMED 4.2 / Ngugi -- Slide 1 VALVULAR HEART DISEASES 2023 Slide 2 MITRAL REGURGITATION MWONGERA G. CLARAH 2023 Slide 3 Introduction Mitral regurgitation (MR) is incompetency of the mitral valve causing flow from the left ventricle (LV) into the left atrium during ventricular systole.\nComplications include progressive heart failure, arrhythmias, and endocarditis.\nPrognosis depends on LV function and etiology, severity, and duration of MR. Patients with mild, asymptomatic MR may be monitored, but progressive or symptomatic MR requires mitral valve repair or replacement. Slide 5 Classification Acute Rapid rise in LA pressure Because compliance is normal\nMarked symptomatic deterioration Chronic Gradual LA dilatation with minor increase in pressure\nFew symptoms. LV dilates slowly\nLV diastolic and LA pressures gradually increase as a result of chronic volume overload of the LV Slide 6 Classification Continued Primary - common causes are mitral valve prolapse and rheumatic fever Secondary- due to LV dilation or infarction. Slide 7 Etiology Mitral valve prolapse Damage to valve cusps and chordae (e.g. rheumatic heart disease, endocarditis)\nDilatation of the LV and mitral valve ring (e.g. coronary artery disease, cardiomyopathy)\nIschemia or infarction of the papillary muscle Myocardial infarction Following Mitral valvotomy or valvuloplasty Slide 8 Mitral valve prolapse ‘floppy’ mitral valve\nMore common cause of mild mitral regurgitation It is caused by\ncongenital anomalies\ndegenerative myxomatous change Connective tissue disorders such as Marfan’s syndrome Slide 9 MVP cont’d In its mildest forms,\nthe valve remains competent but bulges back into the atrium during systole,\ncausing a mid-systolic click but no murmur.\nIn the presence of a regurgitant valve,\nthe click is followed by a late systolic murmur, Lengthens as the regurgitation becomes more severe. A click is not always audible\nphysical signs vary with posture and respiration. Slide 10 Cont’d Progressive elongation of the chordae tendineae leads to increasing mitral regurgitation,\nIf chordal rupture occurs, regurgitation suddenly becomes severe.\nThis is rare before the fifth or sixth decade of life.\nIt is associated benign arrhythmias, atypical chest pain and a very small risk of embolic stroke or TIA. Long-term prognosis is good Slide 11 Other causes Mitral valve function depends on\nchordae tendineae\nTheir papillary muscles Dilatation of the LV distorts the geometry of these and may cause mitral regurgitation\nDilated cardiomyopathy and heart failure from coronary artery disease are common causes of so-called ‘functional’ mitral regurgitation.\nEndocarditis is an important cause of acute mitral regurgitation. Slide 12 Clinical Features Symptoms Depends on severity of the regurgitation. Chronic mitral regurgitation produces a symptom complex similar to MS. Sudden-onset mitral regurgitation usually presents with acute pulmonary oedema.\nDyspnoea (pulmonary venous congestion) \nFatigue (low cardiac output) \nPalpitation (atrial fibrillation, increased stroke volume) \nOedema, ascites (right heart failure) Slide 14 Signs Seen in Moderate or severe MR. Include: Atrial fibrillation/flutter. Cardiomegaly: displaced hyperdynamic apex beat\nApical pansystolic murmur ± thrill- Regurgitant jet causes an apical systolic murmur which radiates into the axilla and may be accompanied by a thrill Soft S1, apical S3 -Increased forward flow through the mitral valve causes a loud third heart sound.\nSigns of pulmonary venous congestion -Crepitations, pulmonary oedema, effusions. Signs of pulmonary hypertension and right heart failure Slide 15 Investigations ECG Left atrial hypertrophy (if not in atrial fibrillation)\nLeft ventricular hypertrophy\nChest X-ray\nEnlarged LA\nEnlarged LV\nPulmonary venous congestion\nPulmonary oedema (if acute) Slide 16 Investigations cont’d Echo\nDilated LA, LV\nDynamic LV (unless myocardial dysfunction predominates) Structural abnormalities of mitral valve (e.g. prolapse) Slide 17 Transesophageal echocardiogram shows mitral valve prolapse, with one leaflet bulging towards the LA (arrow). Slide 18 Doppler\nDetects and quantifies regurgitation\nDetects Pulmonary hypertension Jet of mitral regurgitation on colour Doppler (arrow). Slide 19 Investigations cont’d Cardiac catheterization \nDone before surgery, mainly to determine whether coronary artery disease (CAD) is present.\nDilated LA, dilated LV, mitral regurgitation Pulmonary hypertension\nCoexisting coronary artery disease Slide 21 Management Mitral regurgitation or moderate severity can be treated medically\nHigh afterload may worsen the degree of regurgitation, and hypertension should be treated with vasodilators, such as ACE inhibitors.\nMedical management of MR Diuretics\nVasodilators, e.g. ACE inhibitors\nDigoxin if atrial fibrillation is present\nAnticoagulants if atrial fibrillation