Randomized Trial Evaluating Percutaneous Coronary Intervention for the Treatment of Chronic Total Occlusion
Authors: Lee Seung-Whan , Lee Pil Hyung , Ahn Jung-Min , Park Duk-Woo , Yun Sung-Cheol , Han Seungbong , Kang Heejun , Kang Soo-Jin , Kim Young-Hak , Lee Cheol Whan , Park Seong-Wook , Hur Seung Ho , Rha Seung-Woon , Her Sung-Ho , Choi Si Wan , Lee Bong-Ki , Lee Nae-Hee , Lee Jong-Young , Cheong Sang-Sig , Kim Moo Hyun , Ahn Young-Keun , Lim Sang Wook , Lee Sang-Gon , Hiremath Shirish , Santoso Teguh , Udayachalerm Wasan , Cheng Jun Jack , Cohen David J. , Muramatsu Toshiya , Tsuchikane Etsuo , Asakura Yasushi , Park Seung-Jung 
Published: February 2019

Background:
Procedural results for percutaneous coronary intervention (PCI) in coronary vessels with chronic total occlusion (CTO) have improved in recent years, and PCI strategies have moved toward more complete revascularization with more liberal use of CTO-PCI. However, evidence evaluating CTO-PCI is limited to observational studies and small clinical trials.

Methods:
In this open-label, multicenter, randomized, noninferiority trial, PCI-eligible patients were assigned to receive either 1 of 2 strategies: PCI or no PCI for the qualifying de novo CTO lesion with the option for PCI of obstructive non-CTO lesions at the discretion of the operator. The primary end point was a composite of death, myocardial infarction, stroke, or any revascularization. Health-related quality of life was assessed at baseline and at 1, 6, 12, 24, and 36 months. Because of slow recruitment, the trial was stopped before completion of the 1284 planned enrollments.

Results:

Between March 2010 and September 2016, 834 patients were randomly assigned to the CTO-PCI (n=417) or no CTO-PCI (n=398) strategy. Among the patients assigned to the no CTO-PCI strategy, 78 (19.6%) crossed over to receive staged CTO-PCI within 3 days of randomization. The overall CTO-PCI success rate was 90.6%. Serious nonfatal complications associated with CTO-PCI occurred in 3 patients (1 stroke, 1 cardiac tamponade, and 1 patient with recurrent episodes of ventricular tachyarrhythmia induced by intracoronary thrombus). Approximately half of the patients in each group underwent PCI for an average of 1.3 non-CTO lesions, resulting in a comparable residual SYNTAX score (Synergy Between PCI With TAXUS and Cardiac Surgery; 3.7±5.4 versus 4.0±5.9,
P
=0.42) confined to non-CTO vessels. During a median follow-up of 4.0 years (interquartile range, 2.4 to 5.1 years), there was no significant difference between the CTO-PCI and the no CTO-PCI strategies in the incidence of the primary end point (22.3% versus 22.4%, hazard ratio, 1.03; 95% CI, 0.77 to 1.37;
P
=0.86). Both CTO-PCI and no CTO-PCI strategy were associated with significant improvements but without between-group differences in disease-specific health status that was sustained through 36 months.

Conclusions:
CTO-PCI was feasible with high success rates. There was no difference in the incidence of major adverse cardiovascular events with CTO-PCI versus no CTO-PCI, but the study was limited by low power for clinical end points and high crossover rates between groups.

Clinical Trial Registration:

URL:
https://www.clinicaltrials.gov
. Unique identifier: NCT01078051.