Long-Term Effects of Surgical Septal Myectomy on Survival in Patients With Obstructive Hypertrophic Cardiomyopathy

Abstract

Surgical myectomy performed to relieve outflow obstruction and severe symptoms in HCM was associated with long-term survival equivalent to that of the general population, and superior to obstructive HCM without operation. In this retrospective study, septal myectomy seems to reduce mortality risk in severely symptomatic patients with obstructive HCM.

Resultados a longo prazo da miectomia septal no tratamento da cardiomiopatia hipertrófica

“…They also state that the survival is similar to the general population [9,10,12,23,25]. Other consistent data show that the degree of septal hypertrophy and the presence of the pressure gradient in the left ventricular outflow are related to sudden death, and this reinforces the indication for surgery [7,8].…”

“…After this period, the patients showed good survival (87.9%) and with excellent quality of life with improvement of the functional class (from 3.1 to 1.4) and myocardial remodeling represented by the further reduction of the gradient in the left ventricular outflow tract (19.2 mmHg) lately evaluated in relation to the reduction initially assessed (27.8 mmHg). Groups with extensive experience in surgical treatment of HOCM also mention excellent survival rate (95% in 10 years), suggesting that myectomy may offer the opportunity for a normal life, being equivalent to the general population and higher than the population with hypertrophic obstructive cardiomyopathy not operated on [12,13,23,24].…”

“…Currently, assistance units with extensive experience present a mortality rate between 1% and 2%, being able to reach zero in most favorable situations (9,12,13). In our experience, we had an in-hospital death (2.9%) and a survival rate of 87.9% with a mean follow-up of 9.6 years, equivalent to that observed in the international experience, with an 5-year overall survival ranging from 86% up to 96% and in 10 years between 70% and 90% [9,10,12,13]. The recent consensus of American and European Societies of Cardiology have highlighted the surgical septal myectomy as the "gold standard" to reduce the left ventricular outflow obstruction tract and to relief the symptoms in patients with hypertrophic obstructive cardiomyopathy [22].…”

“…The difficulty to visualize the anatomy below the aortic valve can lead to injuries in the aortic valve itself, in the mitral valve, perforation of the left ventricular free wall, interventricular communication, complete atrioventricular block, or septal myocardial insufficient resection compromising both the initial and long-term results [22]. More recently, following the example of most experienced groups [12,13,[23][24][25][26], we have gone ahead with myectomy up to the base of the papillary muscles (extended myectomy), and we have used as a routine, the intraoperative transesophageal echocardiography [15]. It is recommended that the return to cardiopulmonary bypass for expansion of septal myectomy should always be performed when the intraoperative residual gradient of the left ventricular outflow tract exceeds 20 mm Hg [22,23].…”

“…Over the years, septal myectomy surgery has been proven to be a safe and effective procedure in reducing the left ventricular outflow obstruction with relief of the symptoms and improved quality of life in otherwise symptomatic patients and not responding to optimal medical treatment [3,4,[10][11][12][13]. In most cases, the mitral insufficiency or changes in the subvalvular apparatus can be corrected without being necessary to replace the mitral valve [14,15].…”