INTRAOPERATIVE CHANGES OF LEFT VENTRICULAR FUNCTION AFTER PARTIAL LEFT VENTRICULECTOMY

Abstract

Introduction: Partial left ventriculectomy (PLV) has been evaluated as an alternative treatment for patients with severe cardiomyopathies. Initial results of this procedure demonstrated improvement of left ventricular (LV) function and reversion of congestive heart failure in patients with dilated cardiomyopathies. Nevertheless, high incidences of heart failure progression and arrhythmia related deaths have been reported in the early postoperative period. [1,2] The anesthetic management and the intraoperative modifications of LV function after PLV were analyzed in this study. Methods: Thirty-seven patients with dilated cardiomyopathy were submitted to PLV. They were in NYHA functional class III (16) or IV (21). PLV was associated with mitral annuloplasty in 27 patients and to mitral replacement in 2. Total intravenous anesthesia was used. Dobutamina associated with vasodilators infusion was routinely employed at the end of cardiopulmonary bypass (CPB). LV function was studied by transesophageal echocardiography (TEE) and hemodynamic evaluation. Results: There were no intra-operative deaths and only 13 patients had the necessity of intraaortic balloon pump insertion after CPB. Significant changes of LV diastolic diameter (from 87.6 +/- 8.4 to 74.7 +/- 7.2 mm) and LV wall shortening (from 11.6 +/- 3.3 to 18.4 +/- 4.3%) were documented by TEE. Concomitantly, cardiac index increased from 2.01 +/- 0.42 to 2.8 +/- 0.48 and pulmonary wedge pressure decreased from 26.4 +/- 9.6 to 18.6 +/- 7.4 mmHg at the end of CPB. Otherwise, there were 7 hospitalar deaths (18.9%) due to ventricular failure (5), arrhythmia (1) or coagulopathy (1). The surviving patients were followed for a mean of 22.3 months. Despite the maintenance of LV function improvement at late follow-up, other 9 patients died during the first 6 months of follow-up and actuarial survival rates were 56.7 +/- 8.1% at 12 and at 36 months. Discussion: PLV associated when necessary with mitral insufficiency correction improves LV function and ameliorates congestive heart failure in patients with dilated cardiomyopathy. Furthermore, the mid-term course of the surviving patients seems to be characterized by the stabilization of the underlying disease for up to 2 years of follow-up. On the other hand, early survival after this operation appears to be limited by the high incidence of heart failure progression due acute maladaptation of LV function.