Outcome of septal myectomy in patients with hypertrophic obstructive cardiomyopathy

Objectives-To study the outcome of septal myectomy in patients with hypertr ophic obstructive cardiomyopathy. Design-Septal myectomy in patients with hypertrophic cardiomyopathy with ob struction of the left ventricular outflow tract (HOCM) is symptomatically e ffective, and complication rates have been found to be low in large centres performing the procedure routinely. Representing a small centre we studied the outcome after septal myectomy in 11 consecutive patients, aged 44 +/- 21 (mean +/- SD) years with HOCM myectomized at our institution from 1991 t o 1998. The patients were evaluated preoperatively using echocardiography a nd left-sided heart catheterization. Results-Eight patients were operated on after medical treatment had failed and three after sudden deterioration of cardiac function. A Morrow myectomy was performed in 10 patients and a modified Konno procedure in one. Signif icant reductions were observed in left ventricular outflow tract gradients (77 +/- 29 to 10 +/- 7 mmHg, p < 0.01; n = 11), the degree of mitral valve regurgitation (grades 0-3) (1.7 +/- 1.0 to 0.8 +/- 0.7, p < 0.01; n = 11), NYHA functional classification score (2.4 +/- 1.0 to 1.5 +/- 0.7, p < 0.01; n = 11) and all five patients with angina preoperatively had an improved C CS angina classification score. There were no operative or early postoperat ive (30 days) deaths. One patient operated on with the modified Konno proce dure was reoperated for a septal patch suture leak. During follow-up (43 +/ - 24 months, range 11-83), the linearized mortality rate was 3.6% per year. One patient died from a pancreas cancer, one probably from coronary artery disease and one suddenly of unknown cause. Conclusion-We conclude that septal myectomy efficiently relieves symptoms i n HOCM patients, possibly reflecting the direct as well as secondary effect s of left ventricular outflow tract gradient reduction. The present results , obtained at a smaller centre for this procedure, should be considered whe n choosing from available therapeutic alternatives when medical therapy fai ls: dual chamber pacemaker implantation, percutaneous transluminal septal m yocardial ablation or myectomy.