The Alkmaar CTO Registry: A Retrospective Cohort Evaluating the Introduction of a Dedicated CTO Program

Percutaneous coronary interventions (PCI) of chronic total occlusions (CTO) are high risk procedures with low success rates compared to standard PCI. Recently the 'hybrid approach' method has been developed to increase success rate. In 2015 we set up a dedicated program to systematically treat CTOs by this hybrid approach. This retrospective, observational registry aims to report achieved results in a single PCI centre.

We reviewed all CTO procedures between January 2012 and December 2017. Procedures performed by dedicated operators after December 2014 were assigned to the hybrid cohort, procedures done before this time or performed by a non-CTO operator were assigned to the non-hybrid cohort. Procedural techniques, difficulty of lesions, J-CTO scores, outcomes and complications were analysed. In total 505 procedures were included. Average J-CTO score was 1.9 ± 1.1, which was significantly higher in the hybrid cohort (2.1 ± 1.2 vs. 1.6 ± 1.1; p < 0.001). Overall procedural success rate was 75.4% with significantly higher success rates in the hybrid cohort (81.2% vs. 68.2%; p < 0.001). Combining both cohorts, overall success rate increased over the years (2012-2017 respectively 65.2%, 60.0%, 71.7%, 83.2%, 77.9% and 81.4%). Complication rate was higher in the hybrid cohort compared to the non-hybrid cohort (4.6% vs 0.4%, respectively; p = 0.026).

By introducing a systematic CTO program, including use of the hybrid approach, we observed higher success rates of PCI CTO, despite increased complexity of the lesions (higher J-CTO score). The occurrence of MACE was in accordance with current literature.

Our registry demonstrates that introduction of a dedicated CTO program increases success rates of CTO treatments despites increased lesions difficulty and with acceptable MACEs rates.