Hot Line studies from ESC Congress 2026 highlight the complexity of improving cardiovascular outcomes, with new evidence refining the role of immediate coronary angiography after cardiac arrest, identifying which patients benefit from left atrial appendage (LAA) closure during cardiac surgery, advancing treatment options for pulmonary embolism (PE), and questioning the impact of community first-responder activation on short-term cardiac arrest survival.

DISCO
In the DISCO trial and a related meta-analysis from DISCO and four smaller trials, immediate coronary angiography did not improve 30-day survival compared with a deferred strategy in patients without an ECG ST-elevation after out-of-hospital cardiac arrest (OHCA).

The trial, conducted in 23 centers in Sweden, Denmark and the Netherlands, randomized approximately 1,000 patients (mean age 67 years; 25% women) to immediate coronary angiography (within 120 minutes) or to a deferred strategy in which coronary angiography was intended to be delayed for at least 72 hours. Researchers observed no difference in the primary endpoint of survival at 30 days between the groups (54.6% vs. 53.6%). Additionally, there were no significant differences between the groups in terms of survival at 180 days and in secondary endpoints related to neurological recovery.

"With these results from the largest randomized trial investigating this clinical dilemma, we can now conclusively say that immediate coronary angiography after [OHCA] does not improve outcomes over a deferred strategy," said Sten Rubertsson, MD, PhD, lead investigator from Uppsala University in Sweden.

In the meta-analysis involving data from more than 2,000 patients and led by Niels van Royen, MD, of Radboud University Medical Centre, Nijmegen, findings showed no difference in 30-day survival between patients who received immediate coronary angiography and those who did not. "These results show that we can safely delay coronary angiography in patients after OHCA without ST elevation," she said.

LAACS-2
In the LAACS-2 trial conducted in Denmark, Spain and Sweden, researchers investigated whether LAA closure during open-heart surgery may benefit all patients compared with standard care, only to find no significant difference in the primary outcome of stroke or transient ischemic attack between the two after four years of follow-up. Of note, however, researchers said patients who had the highest stroke risk at baseline had a 56% reduction in the primary endpoint with LAA closure, while no significant benefit was seen in those with lower stroke risk.

"Results do not support routine LAA closure in all patients undergoing planned cardiac surgery," said Helena Dominguez, MD, from Bispebjerg University Hospital in Copenhagen. "However, closure appeared to confer protection in patients at high risk of stroke."

PRAGUE-26
In positive news for the treatment of PE, the PRAGUE-26 study, which was simultaneously published in NEJM, found that among patients with intermediate-high–risk acute PE, catheter-directed thrombolysis with alteplase plus anticoagulation therapy led to a lower risk of death from any cause, recurrent PE, or cardiorespiratory decompensation or collapse within seven days of randomization compared with anticoagulation therapy alone.

The findings also showed no apparent differences in bleeding events between the thrombolysis group and the standard-care group within seven days.

"In contrast to interventions for myocardial infarction or stroke, there have been very few advances in the treatment of [PE] over the last 20 years. This has led to a considerable unmet clinical need that we can't ignore," said Viktor Kočka, MD, from Charles University and University Hospital Kralovske Vinohrady in Prague. "Using the blueprint already employed for heart attacks, we were able to demonstrate that specialized interventional treatment can be delivered in tertiary care centers."

HeartRunner
Meanwhile, results from the HeartRunner trial were less positive in terms of community first responder activation after an OHCA. Researchers found that 30-day survival was not significantly improved with community first responders vs. standard practice. However, researchers noted that bystander CPR and defibrillation increased as a result of community first responder activation and no safety concerns were observed.

"[HeartRunner] showed that community first responder systems may significantly improve bystander CPR and defibrillation, but their effect on survival is highly dependent on the time available for responders to intervene before arrival of the ambulance," said Fredrik Folke, MD, PhD, from Copenhagen University Hospital in Denmark. "When this interval is short, the incremental benefit of responder-initiated defibrillation may be limited. It would be interesting to assess their impact in regions with slower ambulance responses, including more rural areas."

Visit ACC's ESC Congress 2026 coverage page to explore the latest science and key takeaways shaping cardiovascular care.

Clinical Topics: Arrhythmias and Clinical EP, Implantable Devices, SCD/Ventricular Arrhythmias, Atrial Fibrillation/Supraventricular Arrhythmias

Keywords: ESC Congress, ESC26, Vascular Diseases, Arrhythmias, Cardiac, Ischemic Stroke, Stroke, Atrial Fibrillation, Out-of-Hospital Cardiac Arrest, Pulmonary Embolism