Outcomes of coronary artery aneurysms: insights from the Coronary Artery Ectasia and Aneurysm Registry (CAESAR).

Background: Coronary artery ectasias and aneurysms (CAE/CAAs) are among the less common forms of coronary artery disease, with undefined long-term outcomes and treatment strategies.

Aims: To assess the clinical characteristics, angiographic patterns, and long-term outcomes in patients with CAE, CAA, or both.

Methods: This 15-year (2006-2021) retrospective single-centre registry included 281 patients diagnosed with CAE/CAA via invasive coronary angiography. Major adverse cardiovascular events included all-cause death, non-fatal myocardial infarction, unplanned ischaemia-driven revascularisation, hospitalisation for heart failure, cerebrovascular events, and clinically overt bleeding. Time-dependent event risks for the CAE and CAA groups were assessed using Cox regression models and Kaplan-Meier curves.

Results: CAEs (n = 161, 57.3%) often had a multi-district distribution (45.8%), while CAAs (78, 27.8%) exhibited a single-vessel pattern (80%). The co-existence of CAAs and CAE was observed in 42 cases (14.9%), and multi-vessel obstructive coronary artery disease was prevalent (55.9% overall). Rates of major adverse cardiovascular events were 14.3% in-hospital and 38.1% at a median follow-up of 18.9 (interquartile range [IQR] 6.0-39.9) months. The presence of CAAs was associated with increased major adverse cardiovascular events risk in comparison to CAE (hazard ratio [HR] = 2.26, 95% confidence interval [CI] 1.38-3.69, p = 0.001), driven by a higher hazard ratio of non-fatal myocardial infarctions (HR = 5.00, 95% CI 1.66-15.0, p = 0.004) and unplanned ischaemia-driven revascularisation in both dilated (HR = 3.23, 95% CI 1.40-7.45, p = 0.006) and non-dilated coronary artery segments (HR 3.83, 95% CI 2.08-7.07, p = 0.001).

Conclusions: Overlap between obstructive and dilated coronary artery disease is frequent. Among the spectrum of dilated coronary artery disease, the presence of a CAA was associated with worse long-term outcomes.