['This study was undertaken to identify the incremental risk factors for early mortality in operations for proximal aortic pathologies.', 'Between September 2000 and May 2010, 240 consecutive patients underwent replacement of various portions of the proximal aorta. Mean age was 56 ± 13 years (range 18 to 84) and female/male ratio was 3/7. Operations were performed emergently in 97, urgently in 21, and electively in 122 patients. Thirty-four patients had previous cardiac or aortic operations. Etiology was acute dissection in 102, chronic dissection in 41, degenerative aneurysm in 61, and other factors (endocarditis, pseudoaneurysm, aortitis, etc.) in 36 patients. The ascending aorta was replaced in all patients. In addition, the aortic arch was replaced in 20 and the root was replaced in 106 patients.', 'The in-hospital mortality rate was 10.4% in the overall group (25/240), 21.6% in emergent cases (21/97), 9.5% in urgent cases (2/21), and 1.6% in elective cases (2/122). Morbidity rates were as follows: stroke 2.7%, temporary neurological dysfunction 13.3%, nonoliguric renal failure 3%, dialysis 5.4%, tracheostomy 3.3%, bleeding requiring revision 3.3%. In multivariate analysis, the presence of malperfusion in patients with acute aortic dissection emerged as the incremental risk factor for mortality (p < 0.0001, odds ratio = 10.37). There was no variable associated with stroke. Emergency/urgency of operation did not emerge as incremental risk factors for mortality.'] Does malperfusion remain the major cause of mortality in proximal aortic operations?