Detection of false lumen perfusion at the beginning of cardiopulmonary bypass in patients undergoing repair of aortic dissection.

Abstract

In patients undergoing surgical repair of aortic dissection, false lumen perfusion during cardiopulmonary bypass may produce central nervous system damage, myocardial ischemia, aortic rupture, and death. We describe a method to detect false lumen perfusion at the beginning of retrograde aortic perfusion that may prevent these complications. Sonicated albumin microbubbles (8 mL) were injected through a side branch of the extracorporeal circulation line to detect true lumen and/or false lumen perfusion of the thoracic aorta at the beginning of cardiopulmonary bypass. Transesophageal echocardiography was used to image aortic perfusion. The study was performed in a cardiac surgery theater. A total of 27 consecutive patients undergoing operation for Type I aortic dissection were studied. All patients underwent surgical repair of aortic dissection and retrograde aortic perfusion through one femoral artery. Patients were divided into three groups: Group I, those having adequate true lumen perfusion: brisk appearance and washout of contrast in the true lumen with no, poor, or delayed opacification of the false lumen; Group II, those having mixed true lumen and false lumen perfusion: simultaneous opacification of both lumens; Group III, those having inappropriate false lumen perfusion: same criteria as for adequate true lumen perfusion applied to the false lumen. The true lumen was perfused in 13 patients, both lumens in 11 patients, and false lumen alone in three patients. In these three patients, cannulation was repeated through the contralateral femoral artery with restoration of true lumen perfusion; the first patient died of diffuse cerebral ischemic damage and renal failure, another one experienced temporary postoperative monoparesis, and the last had no neurologic sequelae. Contrast echocardiography allows immediate detection of retrograde aortic perfusion during cardiopulmonary bypass and may help prevent neurologic complications and death in patients with Type I dissection.