A recent retrospective study found that performing Chronic Total Occlusion Percutaneous Coronary Intervention (CTO-PCI) within 45 days of an Acute Coronary Syndrome (ACS) event does not improve clinical outcomes compared to delayed intervention. The incidence of Major Adverse Cardiovascular Events (MACE) remained comparable between early and late treatment groups over a three-year follow-up period.These findings are published in May 2025 in Cardiovascular Revascularization MedicineThe Burden of ACSACS, which includes both ST-Elevation Myocardial Infarction (STEMI) and Non-ST Elevation Myocardial Infarction (NSTEMI), often involves multi-vessel disease. While European guidelines recommend complete revascularization within 45 days, it has remained unclear if this timeline should apply to a Chronic Total Occlusion (CTO)—a complete blockage of a coronary artery for over three months. These lesions are technically demanding and carry higher procedural risks than standard blockages, necessitating localized data to determine if immediate intervention is superior to a staged, late approach.Study OverviewThe retrospective, international multicenter analysis involved seven specialized centers in Spain and Italy, evaluating 215 patients who underwent successful revascularization of a culprit lesion followed by a planned intervention for a non-culprit chronic total occlusion. The study population was divided into an “early” group, defined as treatment within 45 days, and a “late” group, receiving treatment between 45 days and 6 months. Researchers focused on a composite primary endpoint of all-cause death, myocardial infarction (MI), any subsequent revascularization, and cardiac-related rehospitalization.The key findings from the study include:Among the 215 subjects, 119 patients underwent early CTO-PCI while 96 received late interventionAt the three-year mark, MACE occurred in 28.8% of the early group compared to 23.2% in the late group, representing a statistically insignificant differenceLate intervention patients often presented with more complex procedural features, such as higher J-Chronic Total Occlusion (J-CTO) scores and slightly lower Left Ventricular Ejection Fraction (LVEF) valuesEvidence of positive myocardial viability was significantly more prevalent in the late group (72.9%) than in the early group (33.6%), suggesting a more selective clinical approach for delayed cases.Clinical Relevance and Strategic PlanningFor practicing cardiologists, this research indicates that the 45-day window suggested by European guidelines may not be mandatory for CTO. The lack of additional benefit from early intervention supports a more selective, planned approach for complex blockages. Deferring the procedure allows the inflamed post-infarction myocardium to stabilize, potentially reducing the risks of arrhythmias or further damage during difficult recanalization. Ultimately, meticulous pre-procedural planning and the assessment of myocardial viability should take precedence over rapid revascularization to ensure optimal long-term patient outcomes.Reference Paolucci L, Diego-Nieto A, Jurado-Román A, et al. Timing of chronic total occlusion percutaneous coronary intervention in acute coronary syndromes: Early versus late complete revascularization and clinical outcomes. Cardiovascular Revascularization Medicine. 2026; 83: 1–7