Surveillance imaging following acute type A aortic dissection

Background — Survivors of acute type A aortic dissection (ATAAD) repair remain at risk for long-term complications. Guidelines recommend postoperative imaging surveillance, but adherence is uncertain.

Objectives — The aim of this study was to define the real-world frequency of postoperative imaging and characterize long-term outcomes of ATAAD.

Methods — Population-based administrative health databases for Ontario, Canada, were linked to identify patients who underwent ATAAD repair and survived at least 90 days. Guideline-directed imaging surveillance (GDIS) was defined as undergoing a computed tomographic or magnetic resonance imaging scan at 6 and 12 months postoperatively and then annually thereafter. Multivariable time-to-event analysis explored the associations between GDIS and all-cause mortality and reintervention.

Results — A total of 888 patients who survived urgent ATAAD repair between April 1, 2005, and March 31, 2018, were included. Median follow-up after ATAAD repair was 5.2 years (interquartile range: 2.4-7.9 years). A total of 14% patients received GDIS throughout follow-up. At 6 years, 3.9% of patients had received GDIS. The mortality rate was 4% at 1 year, 14% at 5 years, and 29% at 10 years. Incidence of aortic reintervention was 3% at 1 year, 9% at 5 years, and 17% at 10 years; the majority of these were urgent (68%), and they carried a 9% 30-day mortality rate. Greater adherence to GDIS was associated with mortality (hazard ratio: 1.08; 95% confidence interval: 1.05-1.11) and reintervention (hazard ratio: 1.04; 95% confidence interval: 1.01-1.07).

Conclusions — Adherence to GDIS following ATAAD repair is poor, while long-term mortality and reinterventions remain substantial. Further research is needed to determine if guidelines should be modified.