Etiologic spectrum and clinical features of mitral regurgitation in a Spanish population.

Background And Aim Of The Study: The study aim was to investigate the etiologic spectrum of at least moderate mitral regurgitation (MR) in patients at a tertiary care center in a Spanish region.

Methods: All patients referred for echocardiography with moderate or severe MR, assessed according to the guidelines of the American Society of Echocardiography, were included prospectively in the study.

Results: Between October 2006 and February 2008, a total of 276 patients (157 females, 119 males; mean age 61 +/- 20 years) were enrolled into the study. At the time of evaluation, 67% of the patients were outpatients and the remainder were hospitalized. The NYHA functional class was III-IV in 31% of patients. The main echocardiographic data were: color flow jet area 11 +/- 5 cm2, vena contracta 6.7 +/- 1.9 mm, effective regurgitant orifice area 0.46 +/- 0.28 cm2, left ventricular diastolic and systolic diameters 58 +/- 10 mm and 39 +/- 12 mm, respectively, left ventricular ejection fraction 0.55 +/- 0.19, and pulmonary artery systolic pressure 39 +/- 16 mmHg. The MR was degenerative in 42% of patients, rheumatic in 22%, functional due to idiopathic dilated cardiomyopathy in 18%, functional due to ischemic cardiomyopathy in 7%, congenital in 7%, and had other causes in 4%.

Conclusion: Among this Spanish population, the majority of the moderate or severe MR encountered was organic, with degenerative mitral disease as the most common etiology. Functional regurgitation was present in a significant proportion of patients, with idiopathic dilated cardiomyopathy being the most frequent cause.