Hybrid SPECT MPI and FDG PET in Post-MI Cardiac Care: Bridging Imaging and Intervention for Precision Revascularization in Coronary Artery Disease

Introduction: Ischemic heart disease remains a major health burden in Bangladesh, with many post–myocardial infarction (MI) patients presenting late and often undergoing revascularization without prior assessment of myocardial viability. The introduction of hybrid 99mTc-MIBI SPECT MPI and 18F-FDG Cardiac PET has opened new possibilities for evidence-based, individualized post-MI management. This dual tracer imaging approach enables simultaneous evaluation of perfusion and metabolism, allowing more accurate identification of viable myocardium and supporting optimized revascularization strategies tailored to patient needs.

Objective: To evaluate the role of hybrid SPECT–FDG PET in guiding post-MI management and improving patient outcomes.

Methods: We retrospectively analyzed 75 post-MI patients (27–75 years; 71M/4F) who underwent MPI and FDG PET at INMAS Dhaka (Dec 2020–Dec 2024). Clinical data, coronary angiography, EF%, cardiac biomarkers, and perfusion–metabolism defect patterns were evaluated. Treatment strategies (medical, PCI, or CABG) were correlated with viability findings and outcomes.

Result: Among 75 patients, comorbidities included hypertension (55%), diabetes (53%), dyslipidemia (25%), and CKD (9%). CAG revealed triple-vessel disease in 67%, double-vessel in 20%, and single-vessel in 13%. A mismatch pattern consistent with hibernating myocardium was observed in 18% of patients, while the remainder showed matched (scar), mismatched, or reverse mismatch (stunned myocardium) patterns across the LAD, LCX, and RCA territories. Based on integrated clinical and imaging assessment, 23 patients (30.7%) underwent CABG, 11 (14.7%) PCI, and 41 (54.6%) received optimal medical therapy. Baseline EF on Echo was 34.7 ± 7.6%, which improved to 43.2 ± 6.6% following imaging-guided PCI or CABG. Mortality was higher among those who deferred, delayed or declined the recommended management strategy.

Conclusion: Hybrid SPECT MPI and FDG PET effectively identify viable myocardium and support evidence-based revascularization decisions. Integrating these modalities into routine cardiovascular care can optimize patient selection, reduce unnecessary interventions, and improve clinical outcomes.