The effectiveness of excimer laser angioplasty to treat coronary in-stent restenosis with peri-stent calcium as assessed by optical coherence tomography

We aimed to evaluate the effectiveness of excimer laser coronary angioplasty (ELCA) to treat in-stent restenosis (ISR) due to peri-stent calcium-related stent underexpansion as assessed by optical coherence tomography (OCT).We studied 81 patients (81 lesions with ISR, stent underexpansion, and peri-stent calcium >90°) who underwent OCT imaging both pre and post percutaneous coronary intervention and compared lesions treated with ELCA (n=23) vs. without ELCA (n=58). ELCA use was associated with more calcium fracture (ELCA: 61%, non-ELCA: 12%, p<0.01), larger final minimum lumen area (ELCA: 4.76 mm2 [3.25, 5.57], non-ELCA: 3.46 mm2 [2.80, 4.13], p<0.01), and a larger previously implanted stent area (ELCA: 6.15 mm2 [4.83, 7.09], non-ELCA: 4.65 mm2 [3.84, 5.40], p<0.01). In the multivariable model, ELCA use was associated with peri-stent calcium fracture (odds ratio 46.5, 95% confidence interval: 6.8, 315.9, p<0.001) that, in turn, was associated with final larger lumen and stent dimensions. Finally, contrast injection during ELCA was associated with multiple calcium fractures and fractures even in thicker calcium.ELCA is effective for treating ISR with underexpansion by disrupting peri-stent calcium, facilitating better expansion of the previously implanted stent.