Immediate coronary angiography fails to improve 30-day survival or neurological recovery compared to a deferred strategy in patients resuscitated after an out-of-hospital cardiac arrest without ST-elevation on their electrocardiogram. These conclusions emerged from the DISCO trial, which was presented during a Hot Line session at the European Society of Cardiology Congress in Munich.
DISCO Trial Findings and the Clinical Dilemma
Acute coronary syndrome frequently triggers out-of-hospital cardiac arrest. While immediate coronary angiography and subsequent percutaneous coronary intervention remain standard recommendations for patients presenting with ST-elevation, evidence regarding patients without ST-elevation has historically been limited. Clinical practice has varied widely because definitive evidence on hard clinical outcomes was previously lacking.
Design and Patient Demographics of the DISCO Study
The DISCO trial stands as the largest randomized study investigating this clinical dilemma. Conducted across 23 centers in Sweden, Denmark, and the Netherlands, the study evaluated adult unconscious patients who suffered a witnessed out-of-hospital cardiac arrest, achieved a return of spontaneous circulation, and showed no ST-elevation on prehospital or emergency department ECGs.
Researchers randomly assigned 1,006 patients in a 1:1 ratio to either receive immediate coronary angiography within 120 minutes or undergo a deferred strategy where angiography was delayed for at least 72 hours. In instances of hemodynamic or electrical instability, angiography could be performed earlier than 72 hours. For the immediate group, percutaneous coronary intervention was recommended exclusively on the presumed culprit lesion, leaving non-culprit lesions untreated during the acute procedure.
The enrolled patient population had a mean age of 67 years, and approximately one-quarter of the participants were women.
Detailed Survival and Functional Outcomes
According to data reported by Healio, the trial demonstrated no statistically significant differences between the immediate and deferred angiography groups across multiple primary and secondary endpoints:
- 30-day survival: 53.6% in the immediate group versus 54.6% in the deferred group (P = .67; hazard ratio 0.95; 95% confidence interval 0.74 to 1.21).
- 180-day survival: 48.8% in the immediate group versus 50.2% in the deferred group (P = .6).
- Modified Rankin Scale score of 0 to 3 at 30 days: 39.5% versus 43.6% (P = .19).
- Modified Rankin Scale score of 0 to 3 at 180 days: 38.9% versus 41.6% (P = .37).
- Cerebral Performance Category score of 1 to 2 at 30 days: 39.1% versus 44.2% (P = .1).
- Cerebral Performance Category score of 1 to 2 at 180 days: 39.1% versus 42% (P = .34).
Immediate coronary angiography of the cardiac arrest does not improve survival or neurological outcomes. The case is closed,
stated Professor Sten Rubertsson, lead investigator of the DISCO trial and professor of anesthesiology and intensive care medicine at Uppsala University in Sweden.
Broader Meta-Analysis and Clinical Implications
Complementing the DISCO trial results, researchers from Radboud University Medical Center in Nijmegen, led by Professor Niels van Royen, conducted an individual patient data meta-analysis encompassing five randomized controlled trials and a total of 2,173 patients. Presented by Ms Lente Pol, the meta-analysis similarly found no difference in 30-day survival between patients receiving immediate coronary angiography and those who did not, confirming that clinicians can safely delay the procedure.
Professor Rubertsson noted that these findings provide solid support for current guideline recommendations against routine immediate coronary angiography in this specific patient population, reinforcing the neutral results observed in prior medium-sized trials. He estimated that these findings could impact the acute care of roughly 35,000 to 40,000 resuscitated out-of-hospital cardiac arrest patients annually in Europe, suggesting medical efforts should refocus on the prehospital care arena to improve ultimate survival.
