Aortic involvement in recent-onset giant cell (temporal) arteritis: A case-control prospective study using helical aortic computed tomodensitometric scan

Objective. The prevalence of the involvement of large vessels in giant cell arteritis (GCA) is 3-13%. Aortitis is the most serious complication of GCA. Computed tomodensitometric (CT) scan allows analysis of both the aortic wall and endoluminal part of the aorta. Therefore, we conducted a study using CT scan to analyze aortic abnormalities in patients with recent-onset GCA. Methods. This prospective controlled study compared patients with biopsy-proven GCA with a matched control group based on sex, age, and cardiovascular risk factors. During the 4-week period following diagnosis of GCA, patients underwent an aortic CT scan. The aortic imaging results were blindly compared between both groups. Results. From January 5, 1998 to January 11, 1999, 22 patients and 22 controls were screened by CT scan for aortic involvement. Thickening of the aortic wall was more frequent among patients than controls (45.4% versus 13.6%; P = 0.02). Aortic thickening (mean 3.3 mm) was located on the ascending part of the thoracic aorta in 22.7% of the patients, with no evidence of thickening in the controls (P = 0.05). Thickening of the abdominal aortic wall was noted in 27.3% of the patients and none of the controls (P = 0.02). Conclusion. This study suggests that inflammatory aortic thickening, detected by CT scan, occurs frequently at the time of diagnosis of GCA, and that this condition predominantly occurs on the ascending part of the aorta.