Synchronous and Metachronous Thoracic Aneurysms in Patients with Abdominal Aortic Aneurysms

Objective: Although the association of thoracic aortic aneurysm (TAA) with abdominal aortic aneurysm (AAA) is known, the exact magnitude of the association has not been described. Our goal was to quantify the incidence of TAA in patients with an AAA and assess predictive factors for its diagnosis.

Methods: This was a retrospective review of all patients diagnosed with AAA from 2000-2008. The subsequent development or diagnosis of a TAA was noted and the association between AAA and TAA described.

Results: A total of 2196 patients with an AAA were reviewed. 1082 (49.3%) had a chest computed tomography (CT) during follow-up. 117 patients (10.8%) had a synchronous and 136 (12.6%) a metachronous TAA. Mean time to diagnosis was 2.3 years. Mean diameter was 4.7 ± 1.4 cm for AAA, and 4.7 ± 1.0 for TAA. Indications for the chest CT were variable. Most common were AAA (15%), pulmonary embolus (14%), and lung cancer (11%). Only 38% of AAAs and 14% of TAAs were repaired during the study period. Of all patients with known AAA who were found to have a TAA, 61/253 (24%) underwent repair, had a rupture, or had a TAA >5.5 cm. At a mean follow-up of 43.6 months, there were 79 deaths (7%): 7 AAA-related and 13 from TAA ruptures. Predictors of TAA diagnosis by logistic regression include African American race (odds ratio [OR] = 1.8; P = .02), family history of TAA (OR = 7.6; P = .04), hypertension (OR = 1.7; P = .006), and obesity (OR = 1.7; P = .006). Diabetes, infrarenal AAA location, and smoking have a negative association.

Conclusions: TAAs are relatively common in patients with AAA. Routine or targeted screening with a chest CT at the time of AAA diagnosis may be indicated.