Delayed Angiography Safe in Cardiac Arrest Without ST-Segment Elevation

Optimizing Coronary Intervention Timing After Cardiac Arrest

Determining the optimal timing for coronary angiography in patients resuscitated from out-of-hospital cardiac arrest remains a significant challenge for emergency and critical care teams. While immediate intervention is standard for patients with ST-segment elevation, the benefit of emergent invasive assessment in those without such findings is less clear [1, 2]. Previous short-term data and meta-analyses have suggested that an early invasive strategy may not improve 30-day survival or neurological outcomes compared to a delayed approach [3, 4]. Furthermore, some evidence indicates that certain subgroups, such as women, might even face higher risks with immediate angiography [5]. Despite these insights, the medical community has lacked robust evidence regarding the long-term clinical trajectory of these patients beyond the first year of recovery [6, 7]. A new longitudinal analysis now provides critical data on five-year outcomes to help guide clinical decision-making, allowing physicians to better weigh the risks of immediate catheterization against the benefits of initial neurological stabilization.

Long-Term Outcomes in the COACT Cohort

Out-of-hospital cardiac arrest remains a major global health issue that necessitates clear protocols for post-resuscitation care. The Coronary Angiography After Cardiac Arrest (COACT) trial was the first randomized trial to investigate the potential benefits of immediate versus delayed coronary angiography in patients who achieved return of spontaneous circulation but did not exhibit ST-segment elevation on their initial electrocardiogram. This randomized, open-label, multicenter study focused specifically on patients with an initial shockable rhythm, a presentation that typically suggests a primary cardiac etiology such as ventricular fibrillation. To execute the trial, researchers at 19 Dutch centers enrolled a total of 552 patients to determine if an early invasive strategy would improve long-term survival compared to a delayed approach, where angiography is typically deferred until after neurological recovery. The researchers obtained five-year follow-up data through structured telephone interviews, successfully collecting information for 514 of the 552 original participants (93.1%). Within this followed cohort, 261 patients (50.8%) had been assigned to the immediate angiography group, while 253 patients (49.2%) were assigned to the delayed strategy. Baseline characteristics were similar across the two treatment groups, ensuring a balanced comparison for the long-term analysis. The final results indicated that survival at five years was comparable between immediate and delayed angiography, with no clear benefit or harm associated with either strategy. Specifically, five years after the index hospitalization, 143 patients (54.8%) were alive in the immediate angiography group, compared to 131 patients (51.8%) in the delayed angiography group. The statistical analysis yielded a hazard ratio for five-year survival of 0.95 (95% CI: 0.74 to 1.23; log-rank P = 0.72). For practicing clinicians, this confirms that rushing a hemodynamically stable patient without ST-segment elevation to the catheterization laboratory does not confer a long-term mortality advantage.

Secondary Endpoints and Landmark Analysis

The original COACT trial established that there was no difference in 90-day survival between the immediate and delayed angiography groups. Beyond the primary mortality endpoint, the researchers evaluated several secondary cardiovascular outcomes over the five-year follow-up period, including myocardial infarction, repeat revascularization, heart failure-related hospitalizations, and implantable cardioverter-defibrillator shocks. The data showed that rates of myocardial infarction, heart failure-related hospitalization, and repeat revascularization were low and did not differ between the two treatment groups. This consistency across secondary endpoints reinforces the primary finding that an immediate invasive strategy does not provide a clear clinical advantage over a delayed approach in this patient population. To further investigate the temporal distribution of mortality, the authors conducted a nonprespecified and exploratory landmark analysis (a statistical method that resets the survival clock at a specific time point to evaluate outcomes during distinct intervals). This analysis separated the data into two periods: death occurring up to 90 days and death occurring after 90 days. For the initial period, the hazard ratio for death up to 90 days was 1.11 (95% CI: 0.84 to 1.49; log-rank P = 0.46). However, for the period following the first three months, the hazard ratio for death after 90 days was 0.56 (95% CI: 0.32 to 0.97; log-rank P = 0.04). While a late survival benefit appeared to emerge after the 90-day mark, the researchers noted that its clinical significance remains uncertain. Because this was an exploratory, nonprespecified analysis, the authors concluded that this late survival benefit is most likely due to chance rather than a delayed physiological effect of the timing of the initial angiography. Given that the overall five-year survival and the rates of major adverse cardiovascular events remained comparable between groups, these findings suggest that clinicians can safely defer angiography in resuscitated patients without ST-segment elevation, allowing intensive care teams to prioritize neurological stabilization and diagnostic clarity without compromising long-term cardiac outcomes.

References

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6. Spoormans E, Thevathasan T, Royen NV, et al. One-Year Outcomes of Coronary Angiography After Out-of-Hospital Cardiac Arrest Without ST Elevation: An Individual Patient Data Meta-Analysis.. JAMA cardiology. 2025. doi:10.1001/jamacardio.2025.1194

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