Propensity score analysis in patients with and without previous isolated coronary artery bypass grafting who require proximal aortic and arch surgery

Abstract

ObjectiveThe risk posed by previous isolated coronary artery bypass grafting (CABG) in patients who require proximal aortic or aortic arch surgery is unclear. We compared outcomes of ascending aortic and arch procedures in patients with and without previous CABG. MethodsUsing propensity scores, we created 2 matched groups of patients who underwent proximal aortic surgery, including total arch repairs, at our institution: 126 patients who underwent isolated CABG before the index operation and 126 without previous CABG. Forty-four percent of aortic operations were emergency procedures. Eighty-six patients had a patent previous left internal mammary graft. We compared outcomes between the 2 groups and calculated Kaplan–Meier survival curves. ResultsThe following outcomes were recorded for the patients with previous isolated CABG versus no CABG: operative mortality, 15.9% versus 11.1% (P = .3); 30-day mortality, 13.5% versus 7.1% (P = .1); persistent stroke, 6.3% versus 4.8% (P = .6); and renal failure necessitating hemodialysis at discharge, 7.9% versus 4.0% (P = .2). Previous CABG did not independently predict any adverse outcome, even though patients who underwent previous CABG more frequently needed intra-aortic balloon support (P < .01). The P value for the overall intergroup difference in long-term survival was .06. ConclusionsThis is one of the largest studies yet reported to examine the impact of previous isolated CABG on proximal aortic or arch surgery outcomes. Although these results may be specific to aortic centers of excellence, in this complicated patient cohort, previous isolated CABG did not independently predict any adverse outcome. These results could serve as a benchmark for assessing future endovascular therapies.