Background: Stenting strategies and clinical outcomes of bifurcation lesions in a chronic total occlusion (CTO) vessel after successful recanalization remain to be unknown.
Methods: Between January 2001 and December 2009, 195 (41.1%) patients with 254 (47.0%) bifurcation lesions in CTO vessels from a pool of 564 patients with 659 CTO lesions were included and divided into proximal (n = 134) and distal (n = 120) groups, according to the location of the bifurcation lesions. The primary endpoint was the occurrence of major adverse cardiac events (MACE) at the end of clinical follow-up, including cardiac death, myocardial infarction, or target vessel revascularization (TVR).
Results: Collaterals with Rentrop class 3 were seen more in distal group (100% and 68.3%), compared to proximal group (76.9% and 45.6%). Two-stent technique for proximal bifurcation lesions was used in 24.6%, significantly different from the distal group (6.7%, P < 0.001), without significant difference in composite MACE between proximal and distal groups, or between one- and two-stent subgroups in proximal group. The composite MACE after 1-year in complete revascularization subgroup was 17.9% relative to 29.6% in the incomplete revascularization group (P = 0.044). Stents in long false lumen in main vessel were mainly attributive to decreased TIMI grade flow, with resultant increased in-stent restenosis, total occlusion, TVR and coronary aneurysms. Imcomplete revasculzarization (HR 2.028, P = 0.049, 95%CI 1.002 - 4.105) and post-stenting TIMI flow (HR 6.122, P = 0.020, 95%CI 1.334 - 28.092) were two independent predictors of composite MACE at the 1-year follow-up.
Conclusions: Two-stent was more used for proximal bifurcation lesions. No significant difference was observed in MACE between proximal and distal, or between one- and two-stent subgroups in the proximal group. Placement of a safety wire was critical for proximal bifurcation lesions. Complete revascularization was mandatory to improve clinical outcomes.