THE SPECTRUM OF SEVERE RHEUMATIC MITRAL-VALVE DISEASE IN A DEVELOPING-COUNTRY - CORRELATIONS AMONG CLINICAL PRESENTATION, SURGICAL PATHOLOGICAL FINDINGS, AND HEMODYNAMIC SEQUELAE

Objective: To describe the demographic, pathologic, and hemodynamic pr ofiles of patients with severe rheumatic mitral valve disease in a dev eloping country and to assess their relation to uncontrolled rheumatic disease activity. Design: Retrospective, cross-sectional, cohort stud y. Setting: Tertiary medical center in Soweto, South Africa. Patients: 714 of 737 consecutive black patients, 4 to 73 years old, with pure m itral regurgitation, pure mitral stenosis, or mixed mitral disease who had mitral valve surgery and in whom preoperative and surgical data w ere concordant. Measurements: Valve lesions were evaluated on the basi s of clinical, echocardiographic, hemodynamic, and surgical pathologic data. Active rheumatic carditis was diagnosed according to clinical e vidence for concurrent acute rheumatic fever (Jones criteria), macrosc opic appearances at surgery, and histologic findings. Results: 219 pat ients had pure mitral regurgitation, 275 had pure mitral stenosis, and 220 had mixed lesions. Ongoing rheumatic activity was diagnosed in 10 6 patients with pure regurgitation (47%) and in only 5 patients with p ure stenosis (2%). Pure regurgitation was the most common lesion in th e first and second decades; the relative prevalence of pure stenosis i ncreased with age. Purely regurgitant valves had pliable, unscarred le aflets (95%), dilated mitral annuli (95%), elongated chordae tendineae (92%), and anterior leaflet prolapse (81%). In contrast, purely steno tic valves had fused leaflet commissures (100%) and rigid leaflets (38 %) but no evidence of prolapse. Conclusions: The spectrum of rheumatic mitral valve disease that is hemodynamically severe in developing cou ntries differs from that currently reported in the United States. Seve re, pure rheumatic mitral regurgitation is as prevalent as pure stenos is but has an entirely different time course, surgical anatomy, and re lation to disease activity, suggesting a separate pathophysiologic mec hanism.