Percutaneous coronary intervention in late-presenting acute myocardial infarction without myocardial viability: effects on left ventricular remodeling and function by cardiac magnetic resonance
B P Valente, M J S Souto, F B Sanches, J R T P Costa Junior, I M F Pinto, T S Senra, B P A Coelho, J H H D Delamain, A C C Cervone, G C S Naranjo, P S Morales, P S FarskyAbstract
Introduction
Unreperfused STEMI is frequent, particularly in low- and middle-income countries. Late PCI in patients without myocardial viability remains controversial, with no specific randomized evidence available.
Objective
To evaluate whether late PCI reduces adverse left ventricular remodeling, measured by changes in indexed end-systolic volume (iESV) on cardiac magnetic resonance (CMR), in patients with unreperfused STEMI and absent myocardial viability.
Methods
Prospective, single-center, randomized trial. Patients with STEMI between 24 hours and 30 days, without viability on CMR (transmural late gadolinium enhancement ≥50%), were randomized to PCI plus optimized medical therapy (OMT) or OMT alone. Follow-up CMR was performed at 6–12 months. A pre-specified subanalysis compared viable patients with STEMI between 24 hours and 30 days undergoing PCI with the non-viable PCI group.
Results
Between 2021 and 2024, 95 patients were enrolled; of these, 25 had myocardial viability and 70 did not. The 70 non-viable patients were randomized (34 PCI vs. 36 OMT). At 6–12 months, iESV did not decrease significantly in either group (PCI: -3.0 ml/m², p=0.295; OMT: -4.0 ml/m², p=0.147), with no difference between strategies (p=0.277). Ejection fraction improved significantly only in the OMT group (+2.96%, p=0.031). No difference in major adverse cardiovascular events was observed at 12 months. In the subanalysis, viable patients had lower iESV (45.0 [19.0–75.0] vs. 54.0 [26.0–136] ml/m²; p=0.009) and higher ejection fraction (50.7±10.0% vs. 40.5±11.1%; p=0.001) compared to non-viable patients who underwent PCI.
Conclusion
Late PCI conferred no structural or clinical benefit in patients without myocardial viability. Systematic viability assessment by CMR should guide therapeutic decisions in this population, avoiding unnecessary procedures and exposure to procedural risks without potential benefit.Table 1 PCI vs OMTTable 2 with viability vs without viability