For recanalization of coronary chronic total occlusion (CTO) lesions, subintimal guidewire tracking in both antegrade and retrograde approaches are commonly used.
This study aimed to assess the impact of subintimal tracking on long-term clinical outcomes after recanalization of CTO lesions.
Between January 2009 and December 2016, 474 CTO lesions (434patients) were successfully recanalized in our center. After guidewire crossing in a CTO lesion, those lesions were divided into intimal tracking group (84.6%, n=401) and subintimal tracking group (15.4%, n=73) according to intravascular ultrasound (IVUS) findings. Long-term clinical outcomes including death, target lesion revascularization (TLR), target vessel revascularization (TVR) were compared between the two groups. In addition, the rate of re-occlusion after successful revascularization was also evaluated.
The median follow-up period was 4.7 years (interquartile range, 2.8-6.1). There was no significant difference of the rate of cardiac death between the two groups (intimal tracking vs. subintimal tracking: 7.0% vs. 4.1%; hazard ratio, 0.61; 95% confidence interval [CI], 0.19 to 2.00; p=0.41), TLR (14.3% vs. 16.2%; hazard ratio, 1.34; 95% CI, 0.71 to 2.53; p=0.37), and TVR (17.5% vs. 20.3%; hazard ratio, 1.27; 95% CI, 0.72 to 2.23; p=0.42). However, the rate of re-occlusion was significantly higher in the subintimal tracking group than intimal tracking group at 3-years re-occlusion (4.2% vs.14.5%; log-rank test, p= 0.002, Figure). In the multivariate COX regression, subintimal guidewire tracking was an independent predictor of re-occlusion after CTO recanalization (HR: 5.40; 95% CI: 2.11-13.80; p<0.001).
Subintimal guidewire tracking for recanalization of coronary CTO was associated with significantly higher incidence of target lesion re-occlusion during long-term follow-up period.