Yasu et al. (A-35) used noninvasive magnetic resonance spectroscopy to determine the short- and long-term effects of percutaneous transvenous mitral commissurotomy (PTMC) on exercise capacity and metabolic responses of skeletal muscles during exercise. Data were collected on 11 patients (2 males, 9 females) with symptomatic mitral stenosis. Their mean age was 52 years with a standard deviation of 11.

Among the data collected were the following measurements on changes in mitral valve area (d-MVA) and peak oxygen consumption (d-Vo2) 3, 30, and 90 days post-PTMC:

Days d-Vo2 Subject Post-PTMC d-MVA (cm2

) (ml/kg/min)

1 3 0.64 0.3 2 3 0.76 0:9 3 3 0.3 1.9 4 3 0.6 3:1 5 3 0.3 0:5 6 3 0.4 2:7 7 3 0.7 1.5 8 3 0.9 1.1 9 3 0.6 7:4 10 3 0.4 0:4 11 3 0.65 3.8 1 30 0.53 1.6 2 30 0.6 3.3 3 30 0.4 2.6 4 30 0.5 
5 30 0.3 3.6 6 30 0.3 0.2 7 30 0.67 4.2 8 30 0.75 3 9 30 0.7 2 10 30 0.4 0.8 11 30 0.55 4.2