[Long-term outcome and related predictors of alcohol septal ablation for patients with hypertrophic obstructive cardiomyopathy].

Objective: To observe the long-term prognosis and related outcome predictors for hypertrophic obstructive cadiomyopathy (HOCM) patients underwent alcohol septal ablation (ASA). Methods: A total of 227 consecutive patients(age: (47.8±11.7) years) treated by ASA from September 2005 to December 2013 in our hospital were included and followed-up for 4.42 years(range: ( 1.17-9.93) years). Follow up rate is 97.4%(221/227). General information, medical history, data of ASA and complications during hospitalization were obtained through access to medical records of patients. The patients were followed up by telephone or outpatient visit. Results: During hospitalization period, one patient died due to retroperitoneal hemorrhage, two ventricular fibrillation events and two sustained ventricular tachycardia events occurred and all patients were successfully recovered after electrical cardioversion (defibrillation). Four cardiac tamponade events occurred, 35.7% (81/227) patients experienced temporary three degree atrioventricular block. Five delayed three degree atrioventricular block evens occurred. During follow up, the percent of NYHA Ⅲ/Ⅳclass was significantly reduced (10.1%(23/227)vs. 74.9%(170/227), P=0.000). The incidence of syncope and amaurosis fugax was also reduced(2.6% (6/227) vs. 39.2% (89/227), P=0.035). A total of six patients died (4 cardiac death), one patient complicating atrial fibrillation died of cerebral embolism, one patient died of rectal cancer. One cerebral hemorrhage occurred. Six patients developed-new onset atrial fibrillation. One patient received permanent pacemaker implantation. Eight patients received surgical myocardial resection. Three patients underwent repeated ASA. Survival free of all-cause mortality at 1, 5, 9 year was 100%, 96%, 96%, respectively. Survival free of cardiac death and NYHA Ⅲ/Ⅳclass at 1, 5, 9 year was 100%, 86%, 70%, respectively. Cox-regression analysis showed that residual left ventricular outflow tract gradient after ablation(HR=1.027, 95%CI 1.006-1.048, P=0.010), less volume of injected ethanol(HR=0.596, 95%CI 0.398-0.892, P=0.012), presence of temporary complete atrioventricular block (HR=0.332, 95%CI 0.124-0.886, P=0.028)were independent predictors of cardiac death and NYHA Ⅲ/Ⅳ. Conclusion: Our study results suggest that ASA could significantly improve symptoms and outcome in patients with HOCM. Residual left ventricular outflow tract gradient after ablation, less volume of injected ethanol, presence of temporary complete atrioventricular block during ASA are independent predictors of cardiac death and NYHA Ⅲ/Ⅳ.