Intraoperative contrast echocardiography to evaluate mitral valve operations

Abstract

Intraoperative two-dimensional contrast echocardiography was performed on 29 patients undergoing open heart surgery to determine the presence of mitral regurgitation before and immediately after the operative procedure: 14 patients had predominant mitral stenosis, 9 had severe mitral regurgitation and 6 had no mitral valve disease (control subjects). Two-dimensional echocardiography was performed by applying a 5 MHz transducer directly on the heart during injection of saline solution through an apical ventricular sump or transseptal needle, generating contrast microbubbles, with imaging in two planes. Baseline studies were performed after thoracotomy and pericardiotomy before cardiopulmonary bypass, and a second study was done after the operative procedure, with the patient off cardiopulmonary bypass with hemodynamic stabilization before chest closure. No control subject had contrast evidence of mitral regurgitation before or after cardiopulmonary bypass. Two of three patients with mitral valvuloplasty and two of five with commissurotomy required a second operative procedure before chest closure because of persistent mitral regurgitation detected by intraoperative two-dimensional contrast echocardiography. Thirteen of the 15 patients with valve replacement had no mitral regurgitation after cardiopulmonary bypass. Intraoperative two-dimensional echocardiographic findings correlated with data from postoperative clinical examinations and two-dimensional echocardiography-Doppler studies. It is concluded that two-dimensional echocardiography with contrast is an important intraoperative tool for assessing the presence and relative severity of mitral regurgitation after mitral commissurotomy, valvuloplasty or valve replacement. This technique may allow surgeons to be more aggressive in combining reparative operative procedures (that is, commissurotomy and valvuloplasty) in an attempt to retain native valves.