Immediate Operation for Acute Type A Aortic Dissection With Malperfusion
What are the clinical outcomes associated with immediate operation for acute type A aortic dissection complicated by visceral or peripheral malperfusion?
A single-center retrospective review at Stanford was performed using clinical data from patients presenting with acute type A aortic dissection from 2005-2015. The primary endpoint was overall mid-term survival. Inverse probability weighting was used to account for differences between patients who experienced malperfusion syndromes and those who did not. Weighted logistic regression was used to evaluate in-hospital mortality, and mid-term survival was assessed with the restricted mean survival time and weighted Cox regression. Reintervention was assessed with death as a competing risk.
Of 391 patients presenting with acute type A dissection during the specified time interval, 305 had type A dissection extending beyond the ascending aorta and underwent open repair. Of these, 82 (26.9%) presented with visceral, renal, or peripheral malperfusion. There were limited differences between the two populations at baseline, with more patients with diabetes in the cohort without malperfusion and more patients with neurologic deficits at presentation in the group with malperfusion. Using weighted univariable logistic regression, in-hospital mortality in the malperfusion subgroup was no different compared with patients without malperfusion (odds ratio, 1.50; 95% confidence interval, 0.65-3.47; p = 0.3). Using restricted mean survival time, there was no statistically significant difference in mid-term survival between groups, with a mean difference in survival at 8-year follow-up of –50.2 days (95% CI, –366.8 to 266.4; p = 0.8) in patients with malperfusion compared with patients without malperfusion. After accounting for differences in baseline variables, patients with malperfusion had a greater incidence of perioperative morbidity; including acute kidney injury (50.7% vs. 35.0%, p = 0.02), hemodialysis (20.1% vs. 7.0%, p = 0.003), fasciotomy (7.2% vs. 0.5%, p = 0.002), and heparin-induced thrombocytopenia and thrombosis (8.7% vs. 1.8%, p = 0.008). Patients with malperfusion had an increased risk of interventions on aortic branches (12.5% at 10 years) compared with patients without (5.7%; hazard ratio, 3.06; 95% CI, 1.24-7.56; p = 0.02). The median time to reintervention on aortic branches was 2 days for patients with malperfusion compared with 230 days without malperfusion (p = 0.01).
The authors concluded that immediate operation for acute type A aortic dissection complicated by malperfusion is associated with good surgical results.
Acute type A dissection is a life-threatening condition treated with emergent intervention. However, type A dissection complicated by end-organ malperfusion is associated with a high perioperative mortality, and an approach of early endovascular reperfusion (with fenestration) followed by later surgical intervention (after resolution of the ischemic insult) has been practiced for a number of years. This large single-center experience from Stanford suggests that immediate surgery is associated with similar in-hospital and mid-term mortality among patients with compared to those without malperfusion complicating acute type A dissection. However, as is pointed out in the accompanying editorial, https://doi.org/10.1016/j.jtcvs.2018.03.039, not all patients in the present study in the malperfusion group necessarily had significant end-organ dysfunction, which is probably the marker for adverse surgical outcomes. Without data from a prospective, randomized trial, surgeon experience and preference may remain the dominant factor in the management of patients with acute type A dissection complicated by organ malperfusion.
Keywords: Acute Kidney Injury, Aneurysm, Dissecting, Aorta, Cardiac Surgical Procedures, Diabetes Mellitus, Hospital Mortality, Renal Dialysis, Reoperation, Thrombocytopenia, Thrombosis, Treatment Outcome, Vascular Diseases
< Back to Listings