Discussion
Coronary artery aneurysm as a sequel in Kawasaki Disease is seen in approximately 25% of cases, usually occurring at the proximal segments of the coronary artery, ostia or at the bifurcation points (3, 4). Coronary aneurysms are often classified by their maximal internal diameter. A diameter greater than 1.5 times or 50% that of the largest segment of the coronary artery meets diagnostic criteria for aneurysm (5). Giant coronary aneurysms do not have a universal definition but are typically > 8mm in the pediatric population or > 20mm in adults, and/or > 4 times the normal reference coronary artery diameter (6). In adults, coronary aneurysms are often caused by atherosclerosis, in contrast to Kawasaki disease in children, and the incidence lies between 1.5% to 5% with a male predominance (7). The right coronary artery is affected approximately 40% of the time, and complications often include thrombosis, embolization, rupture, and vasospasm (8-10).
Medical management of coronary aneurysms includes antiplatelet monotherapy with aspirin for small coronary aneurysms, and dual antiplatelet therapy with aspirin and a P2Y12-inhibitor for moderate-sized coronary aneurysms (11). Because giant and rapidly expanding coronary aneurysms carry an even greater risk for thrombosis, antiplatelet therapy in conjunction with an anticoagulant is often recommended (11). Ultimately, these aneurysms may require revascularization, either percutaneously or surgically. There is limited outcome data regarding percutaneous coronary intervention (PCI) for giant coronary aneurysms, but it does carry an increased risk for wall rupture, distal embolization, and risk of stent thrombosis (12, 13). For smaller coronary aneurysms between 6-10mm, PCI with polytetrafluoroethylene (PTFE)-covered stents appears to be an appropriate and safe option but has been associated with a high restenosis rate when used for aneurysms greater than 10mm (14). Surgical intervention with CABG is often utilized for severely symptomatic or high rupture risk aneurysms, most carrying obstructive disease as well (15).