Longitudinal stent deformation during coronary bifurcation stenting

Abstract

A distortion of implanted coronary stent along its longitudinal axis during coronary intervention is known as longitudinal stent deformation (LSD). LSD is frequently seen with newer drug eluting stents (DES), specifically with PROMUS Element stent. It is usually caused by impact of guide catheter tip, or following passage of catheters like balloon catheter, IVUS catheter, guideliner, etc. We hereby report a case of LSD during coronary bifurcation lesion intervention, using two-stents technique. Patient had acute stent thrombosis as a complication of LSD, which was successfully managed.

Longitudinal stent deformation (LSD) is defined as distortion of implanted stent in its longitudinal axis . It is frequently reported with few of the second-generation drug eluting stents (DES), mainly with everolimus-eluting PROMUS Element stent (Boston Scientific, Natick, MA, USA) . The deformation of deployed stent is usually caused by impact of guide catheter tip, or following passage of catheters like balloon catheter, IVUS catheter, guideliner, etc. . We hereby report a case of LSD during coronary bifurcation lesion intervention.

A 70-year-old hypertensive, non-diabetic, non-smoker male presented with angina on exertion of 10 days duration. His clinical examination was within normal limits. Electrocardiogram was also within normal limits. Echocardiogram showed left ventricle ejection fraction 0.60, no motion abnormality, and no mitral regurgitation. Coronary angiography revealed mid left anterior descending (LAD) and diagonal-1 (D1) bifurcation lesion of medina type 0,1,1 ( Fig. 1 A ) . Following informed written consent, patient was taken-up for LAD–D1 bifurcation stenting by mini-crush technique . Left coronary artery was cannulated with extra-support 7 Fr., 3.5 EBU coronary-guide catheter (Medtronic Inc., Minneapolis, Minnesota) and both LAD and D1 lesions were individually crossed with 0.014 in. guide wires (Balance Middle-Weight [BMW] Elite wire, Abbott Vascular, Santa Clara, CA, United States.). Both lesions were sequentially pre-dilated with 2.5 × 15 mm semi-compliant balloon (Sprinter balloon, Medtronic). A 2.5 × 28 mm PROMUS Element stent (Boston Scientific) was deployed from ostium of D1, which was followed by another 3 × 38 mm PROMUS Element stent (Boston Scientific) in LAD, using mini-crush technique ( Figs. 1 B, 2 A ). The D1 was rewired with BMW guide wire (Abbott Vascular). The LAD stent was post-dilated with 3.5 × 12 mm non-compliant balloon (Sprinter balloon, Medtronic) at 15-atmospheric pressure. There-after an attempt was made to post-dilate the D1 stent but none of the balloons (2.5 × 15 mm, 2 × 10 mm, 1.25 × 6 mm Sprinter balloon were tried in sequence) could cross the D1 stent via LAD stent struts. The D1 was rewired in-between to choose different entry point, however balloon catheter could cross the D1 through LAD stent. Following these crossing attempts, the LAD stent got longitudinally deformed with luminal narrowing of LAD ( Fig. 2 B). The deformed LAD stent was sequentially dilated with 2.5 × 10 mm followed by 3.5 × 12 mm non-compliant balloon (Sprinter balloon, Medtronic). A further attempt to cross the D1 stent was not successful. At last, the LAD stent was dilated with 3.5 × 12 mm non-compliant balloon (Sprinter balloon, Medtronic) at 18- atmospheric pressure. There was thrombolysis in myocardial infarction-3 (TIMI-3) flow in LAD and D1, with no residual stenosis of LAD ( Fig. 3 , Video 1 ). Final kissing inflation of LAD-D1 stents could not be done. Patient was discharged on day-2 on aspirin 300 mg and clopidogrel 150 mg per day regimen.