Sections View Full Chapter Figures Tables Videos Annotate Full Chapter Figures Tables Videos Supplementary Content +++ KEY FEATURES +++ ESSENTIALS OF DIAGNOSIS ++ Sudden, severe orthopnea Evidence of pulmonary edema S4 Early systolic murmur due to rapid equilibration of left ventricular and left atrial pressures Doppler echocardiography establishes diagnosis, severity, and cause of mitral regurgitation +++ GENERAL CONSIDERATIONS ++ Disruption of the mitral valve apparatus leading to severe regurgitation is uncommon but often results in profound pulmonary edema Because there is insufficient time for the left ventricle and atrium to dilate, filling pressures rise dramatically back to the lung capillaries Forward stroke volume is markedly reduced because of the large regurgitant volume with a normal left ventricular diastolic volume, resulting in forward heart failure as well If not corrected quickly, acute, severe mitral regurgitation can be rapidly fatal The most common causes of acute, severe mitral regurgitation: – Acute myocardial infarction with papillary muscle rupture or dysfunction – Chordal rupture in mitral valve prolapse – Leaflet disruption due to trauma or endocarditis +++ CLINICAL PRESENTATION +++ SYMPTOMS AND SIGNS ++ Severe orthopnea, frank pulmonary edema (pink foam in mouth) Symptoms and signs of the causal event may be present, such as acute myocardial infarction, endocarditis, or trauma +++ PHYSICAL EXAM FINDINGS ++ Low-volume, low-amplitude, and rapid pulse Reduced pulse pressure Low blood pressure may be present later in course Jugular venous distention may be present later in course Increased respiratory rate and diffuse pulmonary rales Pleural effusion may occur later in course Auscultation: – Owing to rapid equilibration of systolic pressure between the left ventricle and atrium, the mitral regurgitant murmur may be short and early systolic, if audible at all – S4 is frequently heard owing to vigorous atrial contraction because of augmented left atrial expansion during systole – P2 may be loud if pulmonary pressures are significantly increased – The murmurs of pulmonic and tricuspid regurgitation may be present with increased pulmonary pressures +++ DIFFERENTIAL DIAGNOSIS ++ Other causes of acute pulmonary edema not associated with mitral regurgitation Aortic stenosis with heart failure Mitral stenosis with heart failure +++ DIAGNOSTIC EVALUATION +++ LABORATORY TESTS ++ Tests specific to the cause of acute mitral valve disruption, such as blood cultures, may be useful +++ ELECTROCARDIOGRAPHY ++ Signs of acute myocardial infarction may be present in cases of papillary muscle rupture +++ IMAGING STUDIES ++ Chest x-ray: – Pulmonary edema without cardiomegaly is classic – Later, other signs of heart failure such as pleural effusions may be seen – Rib fractures may be present if trauma disrupted the mitral valve Echocardiography: – The detection of mitral regurgitation is the most important goal of echocardiography – The color flow jet may not persist ... Your MyAccess profile is currently affiliated with '[InstitutionA]' and is in the process of switching affiliations to '[InstitutionB]'. Please click ‘Continue’ to continue the affiliation switch, otherwise click ‘Cancel’ to cancel signing in. Get Free Access Through Your Institution Learn how to see if your library subscribes to McGraw Hill Medical products. Subscribe: Institutional or Individual Sign In Username Error: Please enter User Name Password Error: Please enter Password Forgot Username? Forgot Password? Sign in via OpenAthens Sign in via Shibboleth