Impact of Semi-closed Cardiopulmonary Bypass in Right Mini-thoracotomy Aortic Valve Replacement
Yoshitsugu Nakamura, Yuta Yasumoto, Daiki Yoshiyama, Miho Kuroda, Shuhei Nishijima, Taisuke Nakayama, Ryo Tsuruta, Yujiro Ito, Naoki Yamauchi
Chibanishi general hospital, Chiba, Japan
(BACKGROUND) Minimally invasive aortic valve replacement through the right mini-thoracotomy (MIAVR) has proved to be a safe approach, however drawback of MIAVR is longer cardiopulmonary bypass (CPB) time when compared to conventional AVR through median sternotomy. We have introduced novel semi-closed cardiopulmonary bypass (SC-CPB) for MIAVR since 2014 to obtain further less invasiveness in MIAVR. The aim of this study to evaluate impact of the SC-CPB by comparing conventional open cardiopulmonary bypass (O-CPB) in MIAVR.
(METHODS) SC-CPB circuit includes the functions of oxygenation, filtration, and air elimination in a compact manner in connection with a centrifugal pump. The venous line was directly connected to a centrifugal pump via air elimination system without open venous reservoir. A reservoir only for a vent and suckers was connected on the circuit. We retrospectively reviewed 203 MIAVRs performed from March 2014 to February 2020 and compared the outcomes of patients undergoing MIAVR using SC-CPB (Group S, n=144) with MIAVR using O-CPB (Group O, n=59). Demographic characteristics including age, body surface area, EuroSCORE II, hemoglobin level were similar in both groups.(RESULTS)CPB time was similar in both groups. There was significant difference in priming volume (SC-CPB vs O-CPB: 833 ml vs 1396 ml, p<0.001). There was no hospital mortality in either group. Group O had higher intraoperative blood transfusion rate of packed red cell (19.4% vs 42.4% P-0.001). The mean total amount of chest tube output was smaller in S group (182 +/- 157ml vs 227 +/- 164, P=0.045). Duration of hospital stay was shorter in S group (10 +/- 6 vs 12 +/- 8, P=0.03).(CONCLUSIONS) SC-CPD contributed to reduce blood transfusion rate, chest tube output and hospital stay. SC-CPD should be considered in patients undergoing MIAVR.