Balloon mitral valvotomy: an autopsy study

The autopsy findings in 20 patients who died following percutaneous balloon mitral valvotomy are reported. The procedure was attempted in 508 patients. In 17 of the 20 patients, balloon mitral valvotomy was attempted as a salvage procedure. Ten patients died in the immediate post valvotomy period (within 24 h), seven died within a week and three between 1 to 3 months. In 13 patients, the balloon valvotomy successfully opened out one or both commissures. Interatrial septostomy defects created by the transeptal catheter could be identified in 19 of 20 heart specimens. The size of the defects ranged from small (5 mm) openings to large (15 mm) defects especially with double balloon. Marked mitral valvar thickening with nodular calcification was observed in 16 cases. Significant complications leading to mortality included cardiac tamponade (five cases) due to left ventricle apical perforation (3/5 cases). Mitral valve damage in the form of leaflet tears, chordal rupture and long splits in five cases resulted in significant mitral regurgitation. The leaflet tears resulted in detachment of part of the leaflet from the annulus. A late complication noted was infective endocarditis. Associated pulmonary tuberculosis, chronic obstructive pulmonary disease, respiratory infections and multivalvar diseases also contributed to mortality.