Records of 520 patients who underwent mitral valve operations were reviewed to determine the pathophysiology, etiology, anatomy of the valve lesion and use of valvuloplasty techniques. Pure mitral regurgitation, present in 269 patients (52%), was the most common lesion while rheumatic valvulitis, seen in 286 patients (55%), was the most common etiology. Degenerative lesions were found in 168 patients, 33% of the total and 63% of the pure mitral regurgitation group. Two-hundred seventy patients (52%) were treated with valvuloplasty techniques. The incidence of reconstructive procedures was determined for each of the various patient subsets. Overall hospital mortality was 5.6% in the series: 8.4% for mitral replacement compared with 3% for mitral valvuloplasty (p = 0.007). Among patients undergoing primary isolated mitral procedures, hospital mortality for replacement was 7.5% compared with 1.4% for valvuloplasty (p = 0.018). Mitral valvuloplasty seems to provide a therapeutic alternative applicable to the spectrum of mitral valve pathology seen in a North American population.