A dual-vent left heart deairing technique markedly reduces carotid artery microemboli.
BACKGROUND
Cerebral embolization, mainly bubbles, follows aortic declamping in left heart valve operations. Embolization is not prevented by 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 used to monitor the right common carotid embolic activity in 58 consecutive patients who underwent conventional deairing (group 1), 14 consecutive patients who underwent deairing by the dual-vent technique (group 2), and 4 patients who received nonvented coronary artery bypass grafting who did not require deairing (group 3).


RESULTS
The median emboli count recorded after aortic declamping was 1,647 (range, 342 to 6,852) and 101 (range, 0 to 865) in the group 1 and 2 patients, respectively (p < 0.0001). The efficacy of the dual-vent technique improved throughout the series: in the last 7 patients, the emboli counts often approached 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.
Milsom
F P
FP
Cardiothoracic Surgical Unit, Green Lane Hospital, Auckland, New Zealand. pagetm@ahsl.co.nz
Mitchell
S J
SJ
D000328:Adult; D000368:Aged; D006348:Cardiac Surgical Procedures / Q000009:adverse effects* / Q000379:methods*; D002315:Cardiopulmonary Bypass; D002341:Carotid Artery Thrombosis / Q000209:etiology / Q000517:prevention & control*; D018618:Echocardiography, Doppler, Color; D005260:Female; D006349:Heart Valve Diseases / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies