Predictors of late aortic intervention in patients with medically treated type B aortic dissection.

BACKGROUND

Patients with medically managed type B aortic dissection (TBAD) have a high incidence of aorta-related complications over time. Whereas early thoracic endovascular aortic repair (TEVAR) to seal the entry tear can promote aortic remodeling and prevent late aneurysm formation, there are sparse data as to which patients will benefit from such therapy. The goal of this study was to identify clinical and anatomic factors that are associated with the need for subsequent aortic intervention in patients who present with uncomplicated TBAD. These factors could guide the selection of patients who will benefit from TEVAR in the subacute phase.

METHODS

Patients who presented with acute uncomplicated TBAD and were initially managed medically from January 2000 to December 2013 were included in the study. Timing of intervention was stratified into early (within 180 days of initial presentation) and late (181 days and later) cohorts. All patients had follow-up axial imaging studies. These imaging studies were reviewed for anatomic criteria in a retrospective fashion. Predictors of aortic intervention were determined using Cox regression analyses.

RESULTS

There were 254 patients (65% men) with medically managed acute TBAD. The average age at presentation was 66.3 years, and 82.5% had a history of hypertension. Mean follow-up was 6.8 years (range, 0.1-13.6 years). There were a total of 97 (38%) patients who required an aortic intervention during follow-up; 30 (12%) patients required an early intervention, and 67 (26%) were treated during late follow-up (100% for aneurysmal degeneration). Predictors of late aortic intervention included entry tear >10 mm (odds ratio [OR], 2.1; 95% confidence interval [CI], 1.5-3.8; P = .03), total aortic diameter >40 mm at time of presentation (OR, 2.2; 95% CI, 1.8-4.3; P = .02), false lumen diameter >20 mm (OR, 1.8; 95% CI, 1.3-4.7; P = .03), and increase in total aortic diameter >5 mm between serial imaging studies (OR, 2.3; 95% CI, 1.3-3.5; P = .02). Complete thrombosis of the false lumen was protective against late operative intervention (OR, 0.22; 95% CI, 0.11-0.48; P < .01).

CONCLUSIONS

Nearly 40% of patients who present with an uncomplicated TBAD will ultimately require an aortic intervention. All of the late interventions were performed for aneurysmal degeneration. A variety of readily available anatomic features can predict the need for eventual operative intervention in TBAD; accordingly, these parameters can guide the desirability of early TEVAR.