Limited data are available to guide the management of coronary artery aneurysms (CAAs).The authors sought to define the clinical characteristics, identify variables that predict outcomes, and provide long-term data on CAAs.We describe outcomes from 1,729 consecutive patients with CAAs included in an ambispective international registry (CAAR [Coronary Artery Aneurysm Registry]; NCT02563626) involving 33 hospitals across 9 countries in America and Europe.Patients were predominantly male (78.6%; 1,359/1,729) with a mean age of 66 years. Classic cardiovascular risk factors were common, as well as coronary artery disease (85.8%; 1,484/1,729), peripheral vascular disease (10.9%; 188/1,729), and chronic kidney disease (8.0%; 138/1,729). The median number of aneurysms per patient was 1.0 (Q1-Q3: 1.0-1.0), with the most affected territory being the left anterior descending artery (49.6%; 857/1,729). The majority underwent any revascularization procedure (68.5%; 1,184/1,729), mainly percutaneous coronary intervention (50.7%; 877/1,729), and were discharged on dual antiplatelet therapy (65.6%; 1,134/1,729). After a median follow-up of 44.8 months (Q1-Q3: 14.9-88.1), 379 died (21.9%), and 641 (37.1%) developed a major adverse cardiovascular event (MACE) (all-cause death, heart failure, unstable angina, and reinfarction). In a multivariable analysis, age (HR: 1.03; 95% CI: 1.02-1.04; P < 0.001), diabetes mellitus (HR: 1.47; 95% CI: 1.23-1.75; P < 0.001), renal insufficiency (HR: 1.53; 95% CI: 1.19-1.96; P = 0.010), peripheral vessel disease (HR: 1.43; 95% CI: 1.13-1.82; P = 0.003), reduced left ventricular ejection fraction (HR: 0.98; 95% CI: 0.98-0.99; P < 0.001), acute indication for the index coronary angiography (HR: 1.30; 95% CI: 1.08-1.55; P = 0.005), and the number of coronary vessels presenting severe stenosis (HR: 1.11; 95% CI: 1.02-1.20; P = 0.015) were independent predictors of MACEs. Remarkably, only 37 patients presented with local aneurysm complications during follow-up.The long-term prognosis of CAAs is not favorable, with MACEs associated with the underlying risk factor profile for atherosclerotic heart disease.