Background: The vessel healing in patients with coronary artery aneurysms (CAA) that form after drug-eluting stent (DES) implantation is not clear. This study aims to assess the vessel healing in patients with CAA formation after DES implanation.
Methods: From June 2008 to August 2011, follow-up coronary angiography was conducted on 1160 patients who underwent percutaneous coronary intervention (PCI). The average period of follow-up was about (18.95 ± 13.05) months. A total of 175 patients who underwent DES implantation into de novo lesions and who underwent coronary angiography and optical coherence tomography (OCT) examination during follow-up were identified. Patients were divided into the CAA group (n = 31) and non-CAA group (n = 144) based on the results of the coronary angiography. The cardiac events including angina and acute myocardial infarction were noted; in addition, the neointimal thickness and the frequency of strut malapposition and strut uncoverage were also noted.
Results: A greater proportion of incomplete neointimal coverage (17.17% vs. 1.90%, P < 0.001) and strut malapposition (18.20% vs. 1.38%, P < 0.001) were observed in the CAA group. The neointimal thickness in the CAA group was significantly thinner than that in the non-CAA group ((146.6 ± 94.8) µm vs. (192.5 ± 97.1) µm, P < 0.001), as detected via OCT. Patients with CAA formation had a higher frequency of cardiac events including angina pectoris (25.81% vs. 6.25%, P = 0.001) and acute myocardial infarction (9.68% vs. 0.13%, P = 0.002) and thrombosis (16.13% vs. 0.69%, P < 0.001). The longitudinal length of the CAA in the cardiac event group was significantly longer than in the no cardiac event group ((20.0 ± 9.07) mm vs. (12.05 ± 5.38) mm, P = 0.005).
Conclusion: CAA formation after DES implantation is frequently associated with cardiac events as a result of stent malapposition and incomplete neointimal coverage.