Medium-term mortality and safety of complex antegrade CTO-PCI in stable angina: a real world registry- observational comparison with optimised medical therapy

Introduction Chronic total occlusion(CTO)lesions are commonly encountered in patients with coronary artery disease and associated with major adverse cardiovascular outcomes and mortalities.With emerging technical success, percutaneous coronary intervention(PCI) of CTO lesions is considered safe and feasible,and its comparative procedural outcomes and survival benefits against optimal medical therapy(OMT) remain controversial1,2 Objective Our primary aim was to evaluate the benefit of PCI compared with OMT in patients with CTO over extended medium-term follow-up of a dedicated CTO registry. Further objectives were to compare a 5-year all-cause cardiovascular mortality among patients undergoing CTO-PCI compared with optimal medical therapy (OMT) alone. Methods and Results From January 2015 to December 2018 , a total of 125 patients with CTO lesions were enrolled into a large single-centre registry and followed for 5 years. We included patients who had true native vessel CTO , viable myocardium ,and had confirmed J-CTO score >3 .We excluded patients whose data were incomplete, whom had non-viable myocardium , whom not on optimised medical therapy(OMT )or non-compliance with OMT. We classified patients into the CTO-PCI group (n=47) or OMT group (n=44). Patients with multivessel disease received PCI for obstructive non-CTO and with previous coronary artery bypass graft(CABG)included in both groups. Baseline characteristics include cardiovascular risk factors (hypertension, diabetes, etc), procedural complexity(J-CTO, access, technical approach), and 5-year survival benefits in both arms. In the CTO-PCI group, 40 patients (85%) underwent successful revascularization. Average J-CTO score was 3 suggestive of highly complex anatomy. Antegrade approach was used 90%with experienced operator achieving higher procedural success rate of 94%. One patient died within procedure and one died due to covid infection post-operatively. 90% of patients with CTO-PCI were discharged asymptomatically and on optimised anti-anginal therapy whereas all of them continued maximal one anti-anginal medication. On extended follow-up of five years, the majority of CTO-PCI group(96%) had higher survival rates compared to 72% of patients in medical therapy arm. This difference was statistically significance in chi-squared of 9.24 ,with p value of 0.02. Odds ratio after adjustment for baseline factors (OR for mortality with medical therapy compared to successful CTO-PCI) was 8.42 [95% CI , 1.77-40.32]; p= 0.008). Conclusion Successful CTO-PCI in a complex anatomical subset (J-CTO 3 or above) confers a medium-term survival benefit compared to medical therapy alone in addition to better symtom reliefand quality of life. It remains to be seen that if the results can be replicated in large scale multi-centred studies for prognostic significance. If proven, these findings will help us in decision making at Heart MDT for symptomatic patients with complex CTO.