Clinical Study Of Extended Septal Myectomy For Obstructive Hypertrophic Cardiomyopathy

Objective:1. To summarize the experience of extended septal myectomy (modified Morrow procedure) in patients with hypertrophic obstructive cardiomyopathy (HOCM).2. Compared the transthoracic echocardiography (TTE)、ECG of pre-operation、 post-operation and follow up visit, to assessment the release effect of left ventricular outflow tract obstruction (LVOTO), to demonstrate the effect and safety of the operation.3. Through the analysis of the long-term follow-up data, to provide the theoretical basis for the modified Morrow procedure for HOCM, and discuss the therapeutic strategies for HOCM.Methods:1. Materials:62 patients with HOCM underwent modified Morrow procedure from January 2003 to December 2014.2. Operative technology:Extended septal myectomy with modified Morrow procedure was performed in all 62 cases under general anesthesia and standard cardiopulmonary bypass (CPB) with the moderatesystemic temperature. Transesophageal echocardiography (TEE) was performed to evaluate the effect of operation.3. Database collection:preoperative Baseline Characteristics, LVOTG during operation, IVST, postoperative ventilation time, ICU stay, postoperative hospital stay, postoperative, follow-up complications and end points.4. Treatment effect assessment:Compared the TTE、ECG of pre-operation、 post-operation and follow up visit, assessment release effect of left ventricular outflow tract obstruction (LVOTO), to assess the survival rate with Kaplan-Meier curve.5. Cardiac function:follow up postoperative complications and the change of symptoms to assess cardiac function.Results1. All patients were discharged without severe complications (iatrogenic ventricular septal defect or complete atrioventricular block). Intraoperative TEE showed that the mean systolic gradient between the left ventricle and the aorta was decreased from 96.4±38.9 mmHg preoperatively to 13.4±9.9 mmHg(t=12.2,p=0000) after operation, and the thickness of ventricular septum was decreased from 28.1±8.8mmHg to 12.8±4.1mm (t=9.59, p=0.000). Mitral regurgitation and SAM were significantly improved or disappeared.2. During the follow-up,1 patient was dead, the cause was unknown, all patients promptly became completely asymptomatic or complained of mild effort dyspnea only and syncope was abolished, cardiac function of all patients was decreased II-III grade, and TTE showed that the pressure gradient was kept on the post-operational level. Long-term survival rate was 100%,97.6%,97.6%at 1,5 and 10 years.Conclusions:Extended septal myectomy with modified Morrow procedure is a mostly effective method for patients with HOCM, no recurrence. The patients symptoms improved significantly or disappeared, the cardiac function improved significantly, and long-term survival rate was good.