Impact of sex on myocardial perfusion following percutaneous coronary intervention of chronic total coronary occlusions

Objectives: We sought to investigate the impact of sex on myocardial perfusion changes following chronic total coronary occlusion (CTO) percutaneous coronary intervention (PCI) as measured by [15O]H2O 15 O]H 2 O positron-emission tomography (PET) perfusion imaging. Background: CTO PCI has been associated with an increase in myocardial perfusion, yet females are less likely to undergo revascularization. As such, data on the impact of sex on myocardial perfusion following CTO PCI is scarce. Methods: A total of 212 patients were prospectively enrolled and underwent CTO PCI combined with [15O]H2O 15 O]H 2 O PET perfusion imaging prior to and 3 months after PCI. Hyperemic myocardial blood flow (hMBF, mL<middle dot>min-1<middle dot>g-1) - 1 <middle dot>g - 1 ) and coronary flow reserve (CFR) allocated to the CTO territory were quantitatively assessed. Results: This study comprised 34 (16 %) females and 178 (84%) males. HMBF at baseline did not differ between sexes. Females showed a higher increase in hMBF than males (Delta 1.34 Delta 1.34 +/- 0.67 vs. Delta 1.06 +/- 0.74, p = 0.044), whereas post-PCI hMBF was comparable (2.59 +/- 0.85 in females vs. 2.28 +/- 0.84 in males, p = 0.052). Female sex was independently associated with a higher increase in hMBF after correction for clinical covariates. CFR increase after revascularization was similar in females and males (Delta 1.47 Delta 1.47 +/- 0.99 vs. Delta 1.30 +/- 1.14, p = 0.711). Conclusions: The present study demonstrates a greater recovery of stress perfusion in females compared to males as measured by serial [15O]H2O 15 O]H 2 O PET imaging. In addition, a comparable increase in CFR was found in females and males. These results emphasize the benefit of performing CTO PCI in both sexes. Clinical perspective: What is new? center dot CTO PCI has been associated with an increase in myocardial perfusion, yet females are less likely to undergo revascularization. center dot We found a greater recovery of stress perfusion in females compared to males after CTO PCI as measured by serial [15O]H2O 15 O]H 2 O PET imaging, whereas coronary flow reserve was comparable between sexes. center dot The present study adds to the limited body of evidence on the impact of sex on myocardial perfusion following CTO PCI. What are the clinical implications? center dot Our findings suggest that recovery of myocardial perfusion following CTO PCI is achievable in both female and male patients. center dot These results underscore the need to adhere to current guidelines for optimal CTO management in both sexes. center dot Future studies with standardized preprocedural imaging are warranted to increase our understanding of the impact of sex on changes in myocardial perfusion following CTO PCI.