Aneurysmal Degeneration in Patients with Type B Aortic Dissection

The optimal management of type B aortic dissection (TBAD) remains controversial in the era of endovascular therapies. This study reports the outcomes and complication rates of different treatment paradigms for TBAD.

A retrospective review was undertaken of all patients with TBAD from June 2006 to June 2012. Demographics, hospital course, and follow-up visits were analyzed. Patients who underwent surgical interventions were compared to those with medical therapy. Survival rates and predictors of outcome were determined using the Kaplan-Meier method with Cox proportional hazards.

Of 261 consecutive patients who were hospitalized during this period with a confirmed thoracic dissection, 134 (51%) had TBAD. Sixty-two (46%) were women, and the mean age was 66.4 ± 14.9. Median follow-up was 22.4 (0, 184) months. Thirty-five patients underwent surgical intervention with 20 thoracic endovascular aortic repair (TEVAR) and open surgery in 15. The overall 30-day mortality was 7%, and cumulative survival rates at 1, 3, and 5 years were 85% (95% confidence interval [CI], 79-91), 68% (95% CI, 59-78), and 57% (95% CI, 47-69) with no difference between medical versus surgical groups (P = 0.8) and TEVAR versus open surgery group (P = 1.0). Sixty-six (50%) patients developed aneurysmal expansion, which required surgical intervention in 26 (hazard ratios [HR], 0.99; P = 0.96). Malperfusion and rupture only occurred in 5 (HR, 1.57; P = 0.54) and 5 (HR, 3.64; P = 0.01) patients, respectively. Multivariate analysis for overall survival found renal insufficiency (HR, 2.6; P = 0.004) and age (HR, 1.06; P < 0.0001) and rupture (HR 3.3, P = 0.04) were independent predictors of mortality. Intramural hematoma was not a significant predictor of survival (HR, 0.49; P = 0.11).

Medical therapy remains the mainstay of treating TBAD with low morbidity. Surgical interventions are indicated in selected patients with malperfusion or aneurysmal expansion with comparable survival rates.