Abstract Background and aims Whether recanalization of coronary chronic total occlusions (CTO) leads to improved patient outcomes is uncertain. We set out to investigate the use of noninvasive imaging modalities to guide patient selection for percutaneous recanalization of coronary chronic total occlusions (CTO-PCI) and its association with outcomes. Methods Systematic review and meta-analysis of studies involving patients undergoing CTO-PCI to detail use of preprocedural non-invasive imaging, change in clinical endpoints and the occurrence of clinical events in these patient cohorts. PubMed and Embase, the Cochrane Database of Systematic Reviews, the PROSPERO database and the Clinical Trials Registry were searched for relevant randomized and observational studies up to May 2023. This study is registered with PROSPERO. The study primary endpoint was a composite of all-cause death and nonfatal myocardial infarction (MI), with a secondary composite endpoint of cardiovascular death, nonfatal MI and target vessel revascularization (TVR). Additional endpoints were individual components of the composite endpoints along with changes in angina burden, LV ejection fraction, ischemic burden, and infarct extent after PCI. Results Of 1264 publications retrieved, 31 studies (26 observational and 5 randomized) were finally included for a total of 7260 patients. Guidance to CTO-PCI varied greatly among included studies, with only a minority implementing routine preprocedural inducible ischemia and myocardial viability assessment. At a median of 3.1 years (range 1-5 years), the primary endpoint occurred at a rate of 3.1 events per 100 patient-years (95%CI: 2.4-3.7). When non-invasive imaging was used to guide CTO-PCI, patients with myocardial ischemia and/or viability, a reduced risk for the primary endpoint was observed (OR 0.3 95%CI 0.2-0.5) compared to CTO-PCI without evidence of myocardial ischemia and/or viability. CTO-PCI was associated with improvements in SAQ summary score, LVEF, reduction of ischemic burden, improvement in myocardial perfusion (all P-values < 0.01), with no change in the burden of myocardial scarring. At meta-regression analysis, a greater improvement in LVEF was observed in studies enrolling patients with lower average baseline LVEF (≤ 45%) (R2 = 63%, p < 0.0001). Conclusions CTO-PCI led to a significant improvement in symptom status (reduction of chest pain) and LV ejection fraction. CTO-PCI guided by the presence of ischemia and/or viability was associated with improved patient outcomes compared with CTO-PCI in the absence of ischemia and/viability, or in patients where non-invasive imaging testing was not performed. Future randomized clinical trials testing whether ischemia and viability-guided CTO-PCI improves clinical outcomes are lacking and warranted.PRISMA Flow diagramGraphical abstract
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