Long-lasting improvement after septal myectomy for hypertrophic obstructive cardiomyopathy

Background. The most effective treatment of symptomatic patients with hypertrophic obstructive cardiomyopathy is still disputed. Treatment options include medical therapy, pacemaker insertion, percutaneous transluminal septal myocardial ablation, mitral valve replacement, and surgical resection of obstructing muscle. The long-term results of the various treatment options are not well defined. We aimed to demonstrate that septal myectomy is efficacious in reducing or abolishing left ventricular outflow tract gradient and leads to long-lasting symptomatic improvement in most patients. Methods. Twenty-two consecutive patients had septal myectomy between 1981 and the present. Their records were reviewed to document the details of their preoperative status, hospital course, their subsequent clinical outcome, and current status. Results. Mean age at operation was 31.3 years. Preoperatively all patients were disabled by typical symptoms despite aggressive medical treatment. Mean resting gradient was 78 mm Hg. Nine patients required simultaneous associated cardiac procedures. There were no perioperative deaths and minimal morbidity. Two patients died at 6 and 9 years postoperatively of congestive heart failure and arrhythmias. Long-term survivors have been followed up for a mean of 6.6 years. Currently all have minimal or no symptoms. The mean resting gradient was 12 mm Hg. No patient has required reoperation for residual obstruction. Conclusions. Septal myectomy reduces or abolishes left ventricular outflow tract gradient in hypertrophic obstructive cardiomyopathy. Myectomy provides long-lasting symptomatic improvement in most patients. The clinical status of patients late postoperatively can be affected by arrhythmias and myocardial dysfunction.