Between January 2020 and December 2025, a retrospective cohort study at Mohammed VI University Hospital in Marrakech, Morocco, examined 479 late-presenting ST-segment elevation myocardial infarction (STEMI) patients admitted more than 12 hours after symptom onset.
In Plain English: The Clinical Takeaway
- Late Presentation Challenges: Patients arriving more than 12 hours after heart attack symptoms face distinct treatment hurdles, especially in regions with limited emergency access.
- Revascularization Options: Delayed percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG) were compared against conservative medical management.
- Observational Findings: While invasive strategies showed lower unadjusted mortality rates, researchers emphasize these are descriptive associations rather than direct causal proofs.
Evaluating Revascularization Strategies at Mohammed VI University Hospital
Timely reperfusion remains the cornerstone of management in ST-segment elevation myocardial infarction. However, a substantial proportion of patients continue to present beyond the recommended reperfusion window, particularly in low- and middle-income countries. To better understand outcomes in this population, researchers at Mohammed VI University Hospital conducted a retrospective observational cohort study tracking consecutive patients admitted between January 2020 and December 2025, locking the database on September 17, 2026.
Among the 479 patients included in the analysis, treatment strategies were divided into three groups. Delayed percutaneous coronary intervention was performed in 262 patients, representing 54.7% of the cohort. Conservative medical management was adopted in 121 patients, or 25.3%, while a coronary artery bypass grafting strategy was utilized in 96 patients, making up 20.0% of the study group.
| Treatment Strategy | Patient Count (Percentage) | Observed Mortality (%) | LVEF Change (Paired Six-Week) |
|---|---|---|---|
| Delayed PCI | 262 (54.7%) | 19 (7.3%) | 28 ± 7% to 47 ± 8% |
| Conservative Management | 121 (25.3%) | 41 (33.9%) | 35 ± 5% to 42 ± 4% |
| CABG Strategy | 96 (20.0%) | 19 (19.8%) | 23 ± 8% to 44 ± 5% |
Clinical Outcomes and Functional Recovery After Delayed Presentation
During available follow-up, a total of 79 deaths were observed, yielding an overall all-cause mortality rate of 16.5%. Unadjusted observed mortality varied across the cohorts: it was recorded at 7.3% in the delayed PCI group, 33.9% in the conservative-management group, and 19.8% in the CABG-strategy group. Paired six-week left ventricular ejection fraction (LVEF) measurements—reflecting the heart’s pumping efficiency—showed an increase in the PCI group, the conservative group, and the CABG group.
Complementary insights from a Bayesian network meta-analysis examined multivessel disease in STEMI patients and noted that complete revascularization strategies outperform culprit-only approaches in reducing major adverse cardiac events, though optimal target selection methods remain under active investigation.
Contraindications & When to Consult a Doctor
Because treatment allocation in the Moroccan cohort was nonrandomized and mortality comparisons were unadjusted, study authors caution that these findings should not be interpreted as evidence of a causal mortality benefit from delayed revascularization. Patients exhibiting uncertain symptom-onset times, mechanical complications requiring immediate surgery at presentation, or emergency surgery unrelated to coronary disease were excluded from the study.
Future Directions in Late-Presenting STEMI Care
Further prospective clinical trials are required to clarify which late-presenting patients truly benefit from an invasive strategy versus conservative medical therapy. Ongoing investigations, such as the FRAME-AMI trial registered on ClinicalTrials.gov (NCT02715518), continue to provide vital comparative data on revascularization strategies for patients presenting with complex coronary disease.
References
- Clinical Outcomes According to Revascularization Strategy in Patients With Late-Presenting ST-Segment Elevation Myocardial Infarction
- Revascularization Strategies in Patients With ST-Segment Elevation Myocardial Infarction and Multivessel Disease
- ClinicalTrials.gov: NCT02715518
