Malperfusion in Acute Type A Aortic Dissection: Unsolved Problem

Abstract

Despite a reduced incidence of false lumen perfusion with preferential use of axillary arterial perfusion in acute type A aortic dissection, malperfusion remains a major cause of operative mortality and sequelae. The incidence of unpredictable malperfusion and its mechanism were examined. We examined the 59 consecutive cases of type A aortic dissection treated surgically, including 17cases (28.8%) with preoperative malperfusion. Whereasfemoral arterial perfusion was used in 7 cases withprofound shock, axillary arterial perfusion was employed in the remaining 52 cases. Organ perfusion was assessed with various modalities including transesophageal echocardiography, orbital Doppler, and near-infrared spectroscopy. Although false lumen perfusion was not encountered, persistent or new malperfusion was detected in 5 cases (8.5%) with unrestored true lumen. Malperfusion remained in 3 cases. Of these, bilateral axillary arterial perfusion in 1 case and selective perfusion through the femoral artery in 1 case were effective; however, additional ascending aortic cannulation in 1case was unsuccessful. In the remaining 2 cases, unilateral axillary arterial perfusion led to reduced oxygen saturation in the contralateral frontal lobe, which was restored by bilateral axillary arterial perfusion probably due to augmented collateral circulation. Subclavian steal due to occluded innominate artery was detected in 1 of them. Immediate decision making based on real-time information was beneficial. Despite preferential axillary arterial perfusion, new or persistent malperfusion occurred in 5 cases (8.5%). There is no perfect perfusion route but real-time assessment and individualized navigation may be beneficial in further improving the outcomes.