Acute aortic dissection early after off-pump coronary surgery: true frequency underestimated?
ABSTRACT Since the adoption of off-pump coronary artery bypass surgery (OPCAB), numerous investigators have compared its short- and long-term results with those of on-pump coronary bypass surgery. Some reports of OPCAB were quite favorable, whereas others were critical, claiming that it resulted in incomplete revascularization and reduced venous graft patency. A potentially serious complication of OPCAB, not heretofore sufficiently confronted, is the increased incidence of early postoperative acute aortic dissection, in comparison with the more familiar intraoperative and late-occurring aortic dissection after conventional on-pump bypass surgery.Early postoperative acute aortic dissection after OPCAB appears to be more frequent than was initially thought. Its clinical manifestations can be unusual and often neurologic in nature-rendering diagnosis difficult, causing delays in surgical intervention, and resulting in a high mortality rate.When the physician notes unusual developments in patients after OPCAB that lead to the suspicion of aortic dissection, immediate computed tomography of the chest and surgery should occur if dissection is confirmed. If not detected early, this sequela almost certainly leads to rapid death from aortic rupture. Prevention lies in the strict control of systolic blood pressure during the performance of proximal anastomoses; avoidance of aortic clamping through the use of sequential all-arterial grafts or new-generation mechanical connectors; and, at times, aggressive replacement of the aorta with a prosthetic graft.Herein, we present the cases of 4 patients who sustained acute aortic dissection early after OPCAB. We review the pertinent medical literature.
Article: Delayed chronic type A dissection following CABG: implications for evolving techniques of revascularization.[show abstract] [hide abstract]
ABSTRACT: Postoperative dissection in some patients is related to manipulation of the aorta and accounts for 3% to 5% of deaths after cardiac surgery. Between 1987 and 1999, 109 patients with previous cardiac operations were treated for chronic type A dissection. In 31 of the patients, the etiology was related to aortic manipulation. Twenty-one patients (17 men, 4 women; 67+/-13 years of age) had isolated coronary artery bypass grafting (CABG) as their first operation and were reviewed. The interval between operations was 52.9+/-47.3 months. Reoperation was elective in 11 patients, urgent in 10 patients. Median maximal aortic diameter was 6.8+/-2.1 cm; 9 patients had major aortic insufficiency. The intimal tear was at the partial occlusion clamp site in 12 patients (57.1%), at the cross-clamping site in 4 patients (19.1%), and at the proximal anastomosis in 1 patient (4.8%); 4 patients (19.1%) had multiple tears at several sites. Cystic media necrosis was present in 9.5% of the patients, severe atherosclerosis in 47.6% of the patients, and 42.9% of the patients had both. Nine patients (42.9%) underwent a modified Bentall procedure, 12 patients (57.1%) underwent a supracoronary anastomosis, and all had open distal anastomosis. There were two (9.5%) hospital deaths and three (14.3%) postoperative strokes. Freedom from cardiac or aorta-related mortality was 85.7% at a mean follow-up of 49.3 months. In patients who develop type A dissection of the aorta after previous CABG, the intimal tear most often is at partial occlusion clamp site. This complication is associated with morbidity and mortality. It remains to be seen whether the use of partial occlusion clamps on the pulsating and often diseased aorta during off-pump coronary artery bypass (OPCAB) will increase the risk of delayed iatrogenic dissections.Journal of Cardiac Surgery 15(5):362-7. · 0.87 Impact Factor