LEFT-VENTRICULAR VOLUMES AND FUNCTION IMMEDIATELY AFTER BALLOON MITRAL VALVOPLASTY

To evaluate acute changes in left ventricular volumes and function immediately after successful percutaneous balloon mitral valvoplasty, twenty young patients with isolated rheumatic mitral stenosis (male 9, female 11, mean age 22 +/- 6 years) were studied. The area of the orifice of the mitral valve following valvoplasty, increased from 0.97 +/- 0.27 cm2 to 2.46 +/- 0.75 cm2 (P < 0.001). No significant change was observed in left ventricular end-diastolic volumes (117 +/- 27 ml to 119 +/- 29 ml, P > 0.10), end-systolic volumes (51 +/- 21 ml to 50 +/- 20 ml, P > 0.10), ejection fraction (0.57 +/- 0.10 to 0.58 +/- 0.10, P > 0.10) and left ventricular meridian wall stress (68 +/- 20 . 10(3) dynes / cm2 to 65 +/- 14, P > 0.10) immediately after valvoplasty. There was no acute change in heart rate, left ventricular end-diastolic pressure, cardiac index and grade of mitral regurgitation. Patients with depressed left ventricular ejection fraction (less-than-or-equal-to 0.55, n = 10) and those with normal ejection fraction (> 0.55, n = 10) had similar baseline left ventricular end-diastolic volumes and showed no significant change in volumes and ejection fraction after the procedure, although the former group had a greater orificial area after valvoplasty (P < 0.05). We conclude that an acute increase in the orifice of the mitral valve in patients with rheumatic mitral stenosis is not associated with any significant change in left ventricular volumes and function.