A DUAL-VENT LEFT-HEART DEAIRING TECHNIQUE MARKEDLY REDUCES CAROTID-ARTERY MICROEMBOLI

Background. Cerebral embolization, mainly bubbles, follows aortic decl amping in left heart valve operations. Embolization is not prevented b y conventional left heart deairing methods. We have validated a ''dual -vent'' deairing technique, which uses high-flow left ventricular and aortic venting from the working heart into the cardiopulmonary bypass venous line before aortic declamping. Methods. After left heart valve replacement, intraoperative color-flow Doppler echocardiography was us ed to monitor the right common carotid embolic activity in 58 consecut ive patients who underwent conventional deairing (group 1), 14 consecu tive patients who underwent deairing by the dual-vent technique (group 2), and 4 patients who received nonvented coronary artery bypass graf ting who did not require deairing (group 3). Results. The median embol i count recorded after aortic declamping was 1,647 (range, 342 to 6,85 2) and 101 (range, 0 to 865) in the group 1 and 2 patients, respective ly (p < 0.0001). The efficacy of the dual-vent technique improved thro ughout the series: in the last 7 patients, the emboli counts often app roached the very low levels seen in group 3 patients (median, 8; range , 1 to 16). Conclusions. Cerebral embolization after aortic declamping in left heart valve operations was significantly reduced by this dual -vent deairing technique. (Ann Thorac Surg 1998;66:785-91) (C) 1998 by The Society of Thoracic Surgeons.