L. E. Trakimas1, C. I. Aghaie1, D. S. Mix1, K. Rasheed1, J. L. Ellis1, R. J. Glocker1, A. J. Doyle1, M. C. Stoner1 1University Of Rochester,Vascular Surgery,Rochester, 14642, USA
Introduction: Data suggest that pro-inflammatory mediators play a key role in the formation and enlargement of abdominal aortic aneurysms (AAA). Formation and renewal of intramural thrombus is also associated with inflammation, and is known to contribute to the complexity of aneurysm repair. Current cardiovascular pharmacotherapy includes a number of inflammatory modulators such as aspirin (ASA), Plavix (clopidogrel), statins, and angiotensin-converting enzyme inhibitors (ACE-I). The purpose of our study was to investigate the effect of these inflammatory modulators on radiographically-determined thrombus sac volume (TSV).
Methods: Patients who underwent elective infrarenal aortic repair were identified. Pre-operative CT scans were reviewed, and TSV was obtained using a Hounsfield Unit (HU) restricted region growth algorithm. Receiver-operator characteristic curves were systematically generated for TSV and various cardiovascular pharmacotherapies. Additional co-morbid conditions such as diabetes mellitus (DM) and post-operative complications were also evaluated versus TSV.
Results: A total of 210 patients (mean age = 72.0, SE 0.63 years; mean TSV = 81.9, SE 5.83 cm3) were identified. ASA use was associated with a decreased thrombus sac volume ≤ 50 cc (AUC = 0.616, p= 0.013) (figure) whereas statins (p= 0.258), ACE-I (p= 0.455), and Plavix (p= 0.622) had no correlation to thrombus sac volume. DM was not associated with TSV (p= 0.311). Post-operative bleeding was also not associated with TSV (p = 0.120).
Conclusion: ASA use is associated with decreased TSV in a patient population undergoing elective AAA repair. The effect of ASA over other anti-inflammatory and anti-platelet agents is possibly attributable to its distinct mechanism of cyclooxygenase-1 (COX-1) inhibition. These data suggesting a key role of COX-1 in aneurysm thrombus modulation. DM, a known correlate of aneurysm incidence, is not related to thrombus burden. The potential to alter aneurysm thrombus volume affecting aneurysm morphology may yield a more favorable aneurysmal repair.
