Abstract 4364424: Association Between PET-Defined Ischemia Severity and LVEF Improvement After PCI

Background: The benefit of percutaneous coronary intervention (PCI) in ischemic cardiomyopathy remains debated, particularly following the neutral REVIVED-BCIS2 trial. We evaluated changes in left ventricular ejection fraction (LVEF) following PCI among patients with reduced systolic function and obstructive coronary artery disease stratified by ischemia severity on positron emission tomography (PET). Methods: We retrospectively analyzed patients with LVEF ≤45% who underwent PET rest, stress, and viability myocardial perfusion imaging followed by PCI. Patients with significant scar, defined as summed stress score ≥7 without corresponding F18-fluorodeoxyglucose uptake, were excluded. Patients were then categorized by ischemia severity: those with summed difference score (SDS) <6 in all vascular territories were classified as none/mild, while SDS ≥7 in any vascular territory indicated moderate/severe ischemia. Pre-PCI LVEF was determined by transthoracic echocardiography performed from 6 months before up to 7 days after PCI. Post-PCI LVEF was assessed via echocardiograms performed between 30 days and 1.5 years after PCI. A paired Student t-test was used to determine significance in LVEF changes from pre- to post-PCI. Results: Our cohort included 19 patients with mean age 67±10 years, of which 7 were in the none/mild group and 12 in the moderate/severe group. The baseline LVEF was lower in the moderate/severe group compared to the none/mild group (25% vs 35%, p=0.065). Median time from PET to PCI was 7 days [IQR: 3-12]. The median time to post-PCI echo was 260 days [IQR: 105–389]. There were no significant differences between the moderate/severe group and the none/mild group in utilization of beta blockers (58% vs 86%, p= 0.467), renin-angiotensin-aldosterone system blockers (50% vs 71%, p= 0.668), mineralocorticoid antagonists (25% vs 29%, p= 0.999), or sodium glucose transporter 2 inhibitors (17% vs 29%, p= 0.976). The moderate/severe group had a significant LVEF improvement (+9.6 ± 9.7%, p= 0.006), while the none/mild group showed no improvement (-0.56 ± 6.6%, p= 0.832) (Figure 1). Conclusion: Among patients with viable myocardium, those with moderate–severe ischemia on PET experienced a 10% LVEF improvement after PCI, while patients with minimal ischemia showed no meaningful change. These findings suggest that ischemia rather than viability alone may predict LVEF improvement. Further validation in a larger cohort treated with modern medical therapy is warranted.