Baseline angina burden predicts quality of life and functional improvement in patients with viable myocardium treated for chronic total occlusion.

Chronic total occlusion (CTO) is a common finding in patients with known or suspected coronary artery disease and has a distinctive role in these patients' quality of life. However, there is still a lack of evidence of correct patient selection for percutaneous coronary intervention (PCI). From July 2017 to August 2020, 68 patients with successful PCI of a CTO and previous evidence of viability for PCI by cardiovascular magnetic resonance imaging (CMR) were prospectively included in this single-centre observational study. Of these patients, 62 underwent follow-up CMR, and 56 underwent surveys using the Seattle Angina Questionnaire before PCI and 3, 12 and 24 months after PCI. The CMR results were assessed for volumetric, functional and deformation parameters. From the baseline to the follow-up, there was a significant reduction in the left ventricular volumes (all p < 0.001) and an increase in the left ventricular ejection fraction (57.6 ± 11.6% vs. 60.3 ± 9.4%, p = 0.006). Among the deformation parameters, only the left ventricular radial strain showed significant improvement. The SAQ showed an early improvement that emphasised angina stability and frequency as well as a summary score, which persisted after 24 months. A low SAQ summary score before PCI was the best predictive factor of good clinical improvement thereafter. Improvements in myocardial function and quality of life can be achieved with PCI of a CTO. Patient selection for PCI should be performed primarily among relevantly symptomatic patients when evidence of viability for PCI is present. The SAQ can help guide such patient selection.Trial registration ISRCTN, identifier: ISRCTN33203221. Retrospectively registered on 01.04.2020. https://www.isrctn.com/ISRCTN33203221.