Left ventricular function and geometry in juvenile mitral stenosis.

The purpose of this study was to investigate possible differences between juvenile and adult variety of mitral stenosis (MS) with regard to left ventricular preload, afterload, contractile function and geometry by two-dimensional echocardiography. Thirty six consecutive children and adolescents with MS (Group 1, mean age +/- 1 standard deviation 16 +/- 3 yrs) were compared with an equal number of adults with MS of comparable mitral valve area (Group II, mean age 30 +/- 8 yrs). Patients with juvenile versus adult MS had similar left ventricular ejection fraction (0.57 +/- 0.09 vs 0.57 +/- 0.11, p = not significant (NS)), end-systolic wall stress (64.8 +/- 21 vs 64.3 +/- 25 Kdynes/cm2, p = NS), wall stress to end-systolic volume ratio (2.6 +/- 1.2 vs 2.71 +/- 0.9, p = NS) and mass (77 +/- 19 vs 83 +/- 26 gm/m2 p = NS) but the former had greater end diastolic volume (68 +/- 16 vs 57 +/- 18 ml/m2, p = 0.008) and sphericity index (0.62 +/- 0.19 vs 0.50 +/- 0.19, p = 0.01) and lower mass to volume ratio (1.01 +/- 0.32 vs 1.36 +/- 0.42, p (0.01). Compared to normal controls, adult patients with MS had similar end-diastolic volume (58 +/- 13 vs 57 +/- 18 ml/m2), mass (84 +/- 20 vs 83 +/- 26 gm/m2), mass to volume ratio (1.45 +/- 0.4 vs 1.36 +/- 0.42) but greater wall stress (45.6 +/- 11.7 vs 64.3 +/- 25 Kdynes/cm2, p < 0.001) and lower ejection fraction (0.66 +/- 0.07 vs 0.57 +/- 0.11, p < 0.001). Thus patients with juvenile MS have significantly altered left ventricular geometry and increased preload in response to comparably elevated afterload due to compensatory adaptive process.