Outcomes of acute type A aortic dissection repair in patients under the age of 75 versus 75 and older.

Objective: Elderly patients are less likely to undergo surgery for an acute type A aortic dissection (ATAAD). This study aims to understand the risks of surgical treatment in patients 75 and older.

Methods: This was a retrospective study using an institutional database of patients who underwent ATAAD repair from 2007 to 2021. Outcomes were compared between patients <75 and patients $\ge$ 75. Logistic regression was performed for operative mortality, and Cox regression was performed for long-term mortality.

Results: A total of 601 patients underwent surgery for ATAAD, 112 (18.6%) of whom were ≥75. Patients ≥75 were significantly more likely to undergo hemiarch replacement (vs total arch replacement) and concomitant CABG. Operative mortality was 16.1% in patients ≥75 versus 10.2% in those <75 (p = 0.078). On multivariable logistic regression, age ≥75 was not significantly associated with operative mortality (p = 0.068). Effect of age on long-term mortality was time-dependent: on Cox regression, being 75 or older and within one-year post-discharge was significantly associated with an increased hazard of death (time-dependent HR 4.56; 95% CI, 2.31-9.06; p < 0.001), while age was not associated with an increased hazard of death after the first postoperative year (p = 0.779).

Conclusion: Despite reduced survival during the first postoperative year among patients 75 years and older, operative mortality and late survival were similar across each group. By implication, age alone should not be a deterrent to operative intervention in ATAAD patients, even though further investigation is needed to determine opportunities for improving survival during the first postoperative year after ATAAD repair.