INTRAOPERATIVE AND POSTOPERATIVE EVALUATION OF LEFT-VENTRICULAR FUNCTION

Accurate evaluation of left ventricular function during and after cardiac surgery is essential for a successful outcome. Intraoperative and postoperative evaluation of left ventricular function is still most commonly accomplished with data obtained from a pulmonary artery catheter. Newer techniques are being introduced in the operating room. For example, two-dimensional transesophageal echocardiography is commonly utilized intraoperatively to detect myocardial ischemia and may be used to estimate left ventricular volume and ejection fraction. Recent studies suggest that it may also have a role in the determination of left ventricular contractility. The Doppler capabilities of transesophageal echocardiography provide information about regurgitant flow after mitral valve repair and may be able to measure cardiac output. Other techniques used intraoperatively include determination of myocardial lactate production to detect ischemia and the use of conductance catheters to measure contractility. Postoperatively, a much wider variety of methods is available for evaluation of left ventricular function and includes echocardiography, scintigraphy, positron emission tomography, and magnetic resonance imaging.