Current Evaluation and Management of Patients With Mitral Stenosis

S. H. Rahimtoola
2002 Circulation  
ase presentation: A 28-year-old woman with known mitral stenosis (MS) who was not taking antibiotic prophylaxis presented with new onset of chest pain, atrial fibrillation, and "heart failure." She was treated for "heart failure" and converted spontaneously to sinus rhythm. Echocardiographic/Doppler studies showed a mitral valve gradient (MVG) of 7, a mitral valve area (MVA) of 1.2 cm 2 , 2ϩ mitral regurgitation (MR), no tricuspid regurgitation, normal left ventricular (LV) size and function,
more » ... ize and function, no left atrium (LA) thrombus, and a mitral valve score (University of Southern California [USC] scoring system) of 1, with no calcium in the commissures. At cardiac catheterization, mean pulmonary artery (PA) wedge was 23 mm Hg, mean PA pressure was 25 mm Hg, MVG was 10 mm Hg, and MVA was 1.2 cm 2 . On exercise, mean PA wedge was 30 mm Hg, mean PA pressure was 55 mm Hg, and MVG was 18 mm Hg. On angiography, the LV end-diastolic volume was 80 mL/m 2 , ejection fraction was 0.48, and 2ϩ MR, with normal coronary arteries. After catheter balloon commissurotomy (CBC), the MVA was 2.0 cm 2 , mean PA wedge was 13 mm Hg, and mean PA pressure was 20 mm Hg, with no MR. Her discharge medications were penicillin V 250 mg twice daily and antibiotic prophylaxis for prevention of infective endocarditis. Current Evaluations and Management of MS In almost all patients, MS is the result of previous rheumatic carditis with valve involvement. Severity of MS The relationship of the MVG as a function of the rate of mitral valve flow per diastolic second for various MVAs is shown in Figure 1 . The threshold of onset of pulmonary edema is Ϸ20 mm Hg. Assuming a normal mean LV diastolic pressure (LVDP) of 5 mm Hg, a mean MVG of 20 mm Hg would be necessary 1 to maintain a normal cardiac output (CO). This is a level of LA pressure at which stage 2 of pulmonary edema (interstitial) would be present. An MVG of Ϸ15 mm Hg would be needed to reach stage 1 pulmonary edema (pulmonary congestion). If the LVDP were 10 mm Hg, stage 2 would be reached at a MVG of 15 mm Hg (Figure 1 ). The abnormalities that occur and the outcome of the patient depend on the MVA and LA pressure (Figure 2 ). The severity of MS can be graded on basis of the threshold of pulmonary edema at a certain cardiac output, heart rate, and MVA. The approximate values at a rate of 60 bpm are: Evaluation of Patients With MS A list of methods to diagnose MS and assess its severity and suitability for CBC, as well as to assess associated lesions, is depicted in Table 1 ; the important ones are highlighted. Clinical evaluation can accurately diagnose moderate or severe MS in 92% of patients. 3
doi:10.1161/01.cir.0000029210.14716.01 pmid:12208789 fatcat:e5zt6uh2yfhijodsk66c3pqa6a