2021 Volume 85 Issue 11 Pages 2119-
A 26-year-old male with a history of substance abuse presented with ST-elevation myocardial infarction (STEMI; Figure A) and a complication of left ventricular thrombus. He was treated with a 4.0-mm drug-eluting stent in the proximal left anterior descending artery and warfarin as well as dual antiplatelet therapy. Three weeks later, he again presented with similar chest pain and was diagnosed with non-STEMI. Urgent coronary angiography revealed vasospastic changes in the proximal right coronary artery without apparent angiographic changes within the stent (Figure B). Optical coherence tomography (OCT) was considered suitable to evaluate possible plaque erosion resulting from coronary artery spasm as a mechanism of non-STEMI and to assess stent coverage with anticipation of shortening the triple therapy duration. On the other hand, he had large coronary arteries in which we thought intravascular ultrasound (IVUS) would allow complementary assessment if the coronary artery wall could not be visualized on OCT. Thus, a hybrid IVUS-OCT system (Novasight Hybrid System, Conavi Medical, Toronto, Canada) was used, showing intact coronary artery with no thrombi in either spastic or stented segments (Supplementary File, Movie). Most stent struts were covered with thin neointima without malapposed struts (Figure C,D). The vessel wall could not be fully assessed using OCT due to the large vessel size, but IVUS showed clear delineation of the external elastic membrane.
(A) Total occlusion in the proximal left anterior descending artery with a filling defect (arrow) at the time of first STEMI presentation (B) The stent was patent about three weeks later when patient presented with non-STEMI. (C,D) The external elastic membrane is well visualized on the IVUS image (arrowheads), but neointimal coverage is visible only on the OCT image. IVUS, intravascular ultrasound; OCT, optical coherence tomography; STEMI, ST-segment elevation myocardial infarction.
The hybrid IVUS-OCT system can offset the weaknesses and create synergistic benefits of each imaging modality. Therefore, combined IVUS-OCT catheters have great potential to become an indispensable tool in the cardiac catheterization laboratory.
A.L. has served on advisory boards for Medtronic, Boston Scientific, Philips, Edwards Lifesciences, and Abbott. Y.K. has served as a consultant to ACIST and Abbott.
Supplementary Movie. Hybrid IVUS-OCT pullback of the stented segment. Neither IVUS nor OCT shows evidence of stent thrombosis.
Please find supplementary file(s);
http://dx.doi.org/10.1253/circj.CJ-21-0318
