Effect of percutaneous coronary intervention on chronic total occlusions with documented viability or ischemia: a...

Percutaneous coronary intervention (PCI) for chronic total occlusions (CTO) is common despite the equivocal evidence regarding its benefits. This study aimed to evaluate the impact of pre-PCI viability or ischemia assessment on left ventricular (LV) function, ischemic burden, symptoms, and major adverse cardiovascular events in CTO patients.

A systematic search of PubMed/MEDLINE, EMBASE, CENTRAL, Web of Science Core Collection, ClinicalTrials.eu, and ClinicalTrials.gov was conducted. Studies assessing viability and/or ischemia before PCI with follow-up data were included. Quality was assessed using Cochrane Risk of Bias 2.0 and ROBINS-I tools. Meta-analyses were conducted for quantitative outcomes and narrative synthesis for heterogeneous data. A total of 21 studies (3 randomized, 18 observational) were included; notably, among the randomized trials, only one required the presence of viability or ischemia as an inclusion criterion.

Twenty-one studies were included in this review. Cardiac magnetic resonance was the most used imaging modality, followed by positron emission tomography. Successful PCI was associated with improved LV ejection fraction (MD: 3.97%; 95% CI: 1.51% to 6.42%) but no significant change in LV volumes. Regional segmental wall thickness increased in dysfunctional viable segments (MD: 16.70%; 95% CI: 11.15% to 22.26%), but not in non-viable segments. Successful CTO-PCI improved hyperaemic myocardial blood flow (MBF) (MD: 1.03 mL/min/g; 95% CI: 0.94 mL/min/g to 1.13 mL/min/g), rest MBF (MD: 0.10 mL/min/g; 95% CI: 0.06 mL/min/g to 0.14 mL/min/g), and coronary flow reserve (MD: 1.16; 95% CI: 1.03 to 1.30). The extent of ischemia reduction was associated with improved long-term prognosis and symptom relief.

Pre-PCI viability and ischemia assessment may help identify patients more likely to achieve better functional recovery and symptom relief after successful CTO recanalization. These findings support its role in patient selection and highlight the need for further randomized studies to confirm prognostic value.

The review protocol was registered in PROSPERO (ID: CRD42023426858).