Transesophageal echocardiography in the assessment of hemodynamic failure following cardiac surgery

pp 379-384

Abstract

The feasibility, safety and clinical usefulness of trans-esophageal echocardiography was studied in 12 consecutive patients who underwent cardiovascular surgery and presented unexpected and severe hemodynamic unstability during the postoperative period. Patients with a clear etiology (laboratory alterations, perioperative infarction, cardiac tamponade, tachyarrhythmias) were excluded. In all cases a transthoracic echocardiogram immediately followed by a transesophageal echo-cardiogram was performed in the cardiovascular recovery unit. As the time of the study all patients were under mechanic ventilation with permanent hemodynamic and oximetric monitoring. In 83'4 of the patients, the echocardiographic studies were done within the first72 hours postoperatively. In all cases the transthoracic study was insufficient for detecting the mechanism involved in the hemodynamic failure. No complications related to the transesophageal study were detected. The most frequent cause of hemodynamic deterioration was ventricular dysfunction, being the right ventricle the chamber involved in five cases and the left ventricle in four cases. Both ventricular cavities were involved in only one patient. In two cases superior vena cava thrombosis was the cause of pulmonary embolism. The transesophageal echocardiogram was repeated in two cases, revealing in one case a clear improvement of the ventricular function. We conclude that transesophageal echocardiography is a simple technique to be performed during the recovery phase in cardiovascular surgery and is free of major complications. It also provides relevant information about the etiologic substratum of hemodynamic impairment after cardiac surgery.