A 60-year-old male was admitted to our hospital with typical angina pectoris at rest and troponin-T elevation, and without significant electrocardiogram changes. The patient had undergone everolimus-eluting stent implantation in the circumflex and left anterior descending artery (LAD) 18 months before. Treatment with aspirin, prasugrel, and heparin was started.

Coronary angiography did not demonstrate a new relevant coronary stenosis (A and B), however, the left ventricular angiogram showed a new anteromedial/apical hypokinesia, raising suspicion of a potential problem in the LAD.

Optical frequency domain imaging (OFDI) revealed substantial thrombus formation in the proximal LAD stent that was angiographically inapparent (C, arrows). OFDI demonstrated malapposition of stent struts covered by thrombotic material (D, arrows) that has been suggested to predispose for very late stent thrombosis. After stent expansion and antithrombotic therapy the patient became symptom-free. The boxed area in D demonstrates white thrombus protruding from stent struts.

Here we present a case demonstrating the potential clinical role of OFDI to detect the cause of an acute coronary syndrome in patients without angiographically apparent coronary lesion.

*OCT catheter; ST = stent struts.