Resumen

LIDIETH, Esquivel M.; ROMERO, Luis; VASQUEZ, Gerardo  y  GUTIERREZ, Oswaldo. Etiología de la insuficiencia mitral pura en Costa Rica: estudio ecocardiográfico. Rev. costarric. cardiol [online]. 2003, vol.5, n.1, pp.26-29. ISSN 1409-4142.

Introduction: International studies have demonstrated that mitral valve mixoid degeneration and coronary artery disease are the most frequent causes of pure mitral regurgitation. This cardiac ultrasound study was designed to know each cause prevalence in Costa Rica.   Methods: We included all patients referred to our institution since July 1998 to July 2000 in whom was detected organic pure mitral regurgitation. We performed M-mode and bidimensional imaging and pulsed, continuous and colour flow mapping exploration. We classified patients in rheumatic disease, mixoid degenerative changes, secondary to coronary artery disease, to accelerated degenerative changes, to endocarditis, to collagen disease or other, regarding international criteria. We also assessed severity of mitral regurgitation classifying it in mild, moderate and severe.   Results: We studied 82 patients, 48 females (59.7%) and 34 males (37.8%) between 14 and 87 years old (mean 50.3 +/- 20.7). There were 27 patients with pure mitral regurgitation of rheumatic origin (32.9%), 25 with mixoid degenerative valve disease (30.5%), 12 with coronary artery disease (14.6%), 9 with age-related changes (11%), 4 with mitral annulus elongation secondary to dilated cardiomyopathy not previously suspected (4.9%), 2 with systemic lupus erythematosus valve involvement (2.4%), 2 with no obvious cause (2.4%) and one with endocarditis (1.2%). Sixty-two cases had mild or moderate mitral regurgitation (76.7%) and 18 severe (21.9%). Sixty-one patients had left ventricle systolic function preserved (75.6%) and 21 with some degree of diminished function.   Conclusion: In this study we find a similar prevalence of rheumatic disease and mixoid degenerative disease as most frequent causes of mitral regurgitation, a fact different from international series. Coronary artery disease was the third cause. Most cases were mild or moderate and severe cases had a similar distribution.

Palabras clave : Pure Mitral Insufficiency.