The early efforts to advance open-heart surgery with hypothermia and extracorporeal circulation were directed toward the repair of congenital heart defects. The first goal of cardiac surgery was closure of shunts at the atrial level, then at the ventricular level. Subsequently, the experience provided by exhaustive laboratory research and its clinical application led to what are now routine operations for most septal defects. The development of adjunctive techniques that provide elective cardiac arrest6 and decompression of the left-heart chambers has supplied additional safety in this new field of surgical endeavor.7,17 It was inevitable that these operative techniques would next be applied to meet the challenge of acquired valvular heart disease.
The growing number of teams who can perform open-heart surgery has reduced the backlog of patients with congenital heart disease awaiting operation. The number of patients, however, with complicated forms of acquired valvular heart defects seems to be