Mitral valve replacement in medically unresponsive congestive heart failure due to papillary muscle dysfunction.
Forty patients with a mean age of 65 years (range 44-76 years) were operated on; 30 of 40 patients (75%) had prior myocardial infarction. All had severe therapy-resistant congestive heart failure, 75% (30 of 40 patients) were symptomatic at rest, and 25% (10 of 40 patients) were symptomatic on minimal exertion. Cardiac index ranged from 1.24-2.84 L/min/m2 (mean 1.99). Left ventricular end-diastolic pressure ranged from 3-36 mm Hg (mean 18). All patients had significant mitral insufficiency and contractility was reduced markedly to moderately in 63% (25 of 40 patients). Significant coronary artery disease (obstruction greater than or equal to 75%) was present in all patients. All had mitral valve replacement, 30 had bypass surgery, and 7 left ventricular aneurysmectomy. Five died during surgery or before discharge (early mortality 12.5%). After a mean follow-up period of 16 months, another eight patients died, two with causes not related to the cardiovascular system (total mortality 32.5%). Of 20 patients with a cardiac index greater than or equal to 1.5 L/min/m2 and an ejection fraction greater than or equal to 0.40, 17 survived surgery and improved postoperatively. Mitral valve replacement for this group of patients is recommended.