Abstract 10176: Absolute Perfusion Increase in Remote Myocardium Following Chronic Total Coronary Occlusion Percutaneous Coronary Intervention

Abstract

Introduction: Successful revascularization of a chronic total coronary occlusion (CTO) impacts coronary physiology of the remote myocardial territory. This study evaluated the impact of CTO percutaneous coronary intervention (PCI) on absolute perfusion in remote myocardium. Methods: A total of 164 patients underwent serial [ 15 O]H 2 O positron emission tomography (PET) perfusion imaging at baseline and 3 months after successful CTO PCI to evaluate changes in hyperemic myocardial blood flow (hMBF) and coronary flow reserve (CFR) in remote myocardium subtended by non-target collateral donor coronary arteries. Results: Absolute perfusion indices in the CTO and remote myocardium showed a positive linear correlation before (hMBF: r=0.75, p<0.01; CFR: r=0.77, p<0.01) and after (hMBF: r=0.87, p<0.01; CFR: r=0.81, p<0.01) CTO PCI. An increase in absolute myocardial perfusion (hMBF: 2.29±0.67 to 2.48±0.75 mL·min -1 ·g -1 , p<0.01; CFR: 2.48±0.76 to 2.74±0.85, p<0.01) was observed in the remote myocardial territory between baseline and follow-up. Improvements in remote myocardial perfusion were largest in patients with higher increases in hMBF (β 0.55, 95% CI: 0.46-0.64, p<0.01) and CFR (β 0.52, 95% CI: 0.43-0.61, p<0.01) in the CTO territory, independent of clinical, angiographic and procedural characteristics. Furthermore, lower baseline (hMBF: p<0.01; CFR: p<0.01) and higher post-PCI perfusion (hMBF: p<0.01; CFR: p<0.01) in both the remote and CTO territory were associated with larger perfusion increases in remote myocardium. Conclusions: Baseline and post-PCI perfusion indices in remote and CTO myocardium were positively correlated. An overall increase in remote myocardial perfusion was observed following CTO PCI and the absolute perfusion increase in the CTO territory was an independent predictor of remote myocardial perfusion improvement. Successful CTO PCI impacts coronary hemodynamics in the closely interlinked CTO and remote myocardium.