Fibrin Clot Properties in Aneurysmal Coronary Artery Disease: CARE-ANEURYSM Study

Coronary artery ectasias and aneurysms (CAEAs) are present in up to 5% of patients undergoing coronary angiography. Recent studies indicated an independent association between CAEA and the risk of myocardial infarction but the underlying mechanisms have not yet been elucidated. We evaluated the relationship between CAEA and fibrin clot properties in 60 consecutive CAEA subjects and 60 clinically/angiographically matched controls enrolled across three tertiary centers. Fibrin clot permeability coefficient (Ks), clot lysis time (CLT), and levels of 3-nitrotyrosine, an oxidative stress marker, were assessed. Among patients with CAEA, 52 (86.7%) were male, the median age was 66.0 (59.5–74.1) years, and 30 (50.0%) had concomitant coronary artery disease. Compared with controls, CAEA subjects had 14% lower Ks (p = 0.036), 25% longer CLT (p = 0.001), and 21% higher 3-nitrotyrosine levels (p = 0.002). Multivariable regression analysis showed an association of CAEA with lower Ks, longer CLT, and higher 3-nitrotyrosine levels (all p < 0.05). In CAEA patients, 3-nitrotyrosine levels correlated with Ks (r = −0.31, p = 0.016) and CLT (r = 0.27, p = 0.037). With increasing CAEA peak-to-reference diameter ratio, Ks decreased (p-trend = 0.017), and 3-nitrotyrosine levels increased (p-trend = 0.002). In conclusion, we found that CAEA is independently associated with unfavorably altered fibrin clot properties, reflected by denser clot structure and reduced susceptibility to fibrinolysis. Our findings suggest that oxidative stress may contribute to unfavorable modification of fibrin clot properties in CAEA. With an increase in CAEA size, there is an increase in oxidative stress and worsening of the fibrin clot phenotype.