Subadventitial stenting around occluded stents: A bailout technique to recanalize in-stent chronic total occlusions

Objectives: To evaluate the outcomes of subadventitial stenting (SS) around occluded stents for recanalizing in-stent chronic total occlusions (IS-CTOs). Background: There is little evidence on the outcomes of SS for IS-CTO. Methods: We examined the outcomes of SS for IS-CTO PCI at 14 centers between July 2011 and June 2017, and compared them to historical controls recanalized using within-stent stenting (WSS). Target-vessel failure (TVF) on follow-up was the endpoint of this study, and was defined as a composite of cardiac death, target-vessel myocardial infarction, and target-vessel revascularization. Results: During study period, 422 IS-CTO PCIs were performed, of which 32 (7.6%) were recanalized with SS, usually when conventional approaches failed. The most frequent CTO vessel was the right coronary artery (72%). Mean J-CTO score was 3.1 ± 0.9. SS was antegrade in 53%, and retrograde in 47%. Part of the occluded stent was crushed in 37%, while the whole stent was crushed in 63%. Intravascular imaging was used in 59%. One patient (3.1%) suffered tamponade. Angiographic follow-up was performed in 10/32 patients: stents were patent in six cases, one had mild neointimal hyperplasia, and three had severe restenosis at the SS site. Clinical follow-up was available for 29/32 patients for a mean of 388 ± 303 days. The 24-month incidence of TVF was 13.8%, which was similar to historical controls treated with WSS (19.5%, P = 0.49). Conclusions: SS is rarely performed, usually as last resort, to recanalize complex IS-CTOs. It is associated with favorable acute and mid-term outcomes, but given the small sample size of our study additional research is warranted.