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).