Z-shape phenomenon of optical coherence tomography catheter: potential cause of coronary perforation

A 75-year-old female underwent coronary intervention with rotational atherectomy (RA) due to severely calcified lesions in the left anterior descending artery (Panel A, yellow arrows). After RA with a 1.5 mm burr, multiple cracks were successfully created without any complications (Panel B). To optimize stent deployment in the calcified lesion, we attempted to use optical coherence tomography (OCT). Despite effective lesion modification and support of a guide extension catheter, an OCT catheter (Dragonfly OPTIS, Abbott Vascular, Santa Clara, CA, USA) could not advance through the lesion with its lens part bent toward a side branch (Panel C, a white dotted circle and magnified with a white box). Suddenly, she developed chest pain with ST-segment elevation in V1–4 leads on electrocardiogram. Blow-out perforation from the left main trunk occurred (Panel D), which was treated with covered stents and following bypass surgery to the left circumflex artery. She discharged without any further complications.

Since the withdrawn OCT catheter was severely kinked (Panel E), we speculated that the OCT catheter became kinked and Z-shaped due to being blocked by the residual calcified lesion. It might behave like a sharp blade to injure vessel wall. This speculation was confirmed in the bench-test using a polyurethane-made vessel model with an intentional blockage to prevent an OCT catheter from advancing (Panel F, Video 1). The kinking deformation was observed by a fiberscope as well, which was placed in the side branch (Panel G, Video 2). Herein, we name it a ‘Z-shape phenomenon’ of OCT catheter and report this as a potential cause of coronary perforation. We also confirmed a novel OCT catheter (Dragonfly OpStar, Abbott Vascular) did not encounter ‘Z-shape phenomenon’ in the same setting (Video 3).

Supplementary material

Supplementary material is available at European Heart Journal - Case Reports online.

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