475 Acute Type A Aortic Dissection In-Hours Vs Out-Of-Hours: A Systematic Review and Meta-Analysis

Abstract Introduction Acute type A aortic dissection (ATAAD) is a life-threatening medical emergency requiring immediate surgical intervention. We sought to compare clinical outcomes in patients with ATAAD that undergone surgical repair during in-hours (IH) versus out-of-hours (OOH). Method Electronic database search at PubMed, Ovid, Scopus, Cochrane and Embase was performed from inception till March 2020. Primary outcomes were 30-day mortality, stroke, and re-operation for bleeding; secondary outcomes were previous cardiac surgery and total arch replacement. Results Six articles with a total of 3,744 patients met the inclusion criteria. Re-operation for bleeding and stroke rate were similar, with 18% in IH vs 23% in OOH (RR 0.89, 95% CI [0.73, 1.08], p = 0.24), and 12% in IH vs 13% in OOH (RR 0.83, 95% CI [0.66, 1.03], p = 0.09) respectively. 30-day mortality was significantly lower in IH (26%) vs 24% in OOH (RR 0.81, 95% CI [0.72, 0.90], p = 0.0001). Previous cardiac surgery was higher in IH (5%) vs 4% in OOH patients (p = 0.005). Total arch replacement were similar in both cohorts, 29% in IH vs 32% in OOH (RR 0.96, 95% CI [0.89, 1.04], p = 0.37). Conclusions ATAAD operation during IH and OOH have comparable clinical outcomes. Therefore, operating on such cases should be decided on clinical priority without delay.