Non-STEMI Cardiac Arrest May Not Require Immediate Cath

NEW ORLEANS — Immediate coronary angiography for resuscitated cardiac arrest patients without sign of heart attack doesn’t help, the COACT trial showed.

Survival at 90 days came out similar compared with delaying angiography until after neurologic recovery at 64.5% versus 67.2% (P=0.51), reported Jorrit Lemkes, MD, of Amsterdam University Medical Center, at the American College of Cardiology (ACC) annual meeting and in the New England Journal of Medicine.

U.S. and European guidelines recommend immediate angiography and percutaneous coronary intervention (PCI) for patients with ST-segment elevation myocardial infarction (STEMI), but use for other patients has been debated.

“I think we’ve learned that maybe we don’t have to get up in the middle of the night all the time to be able to do emergency angiography in these patients,” concluded Martin Leon, MD, of NewYork-Presbyterian/Columbia University Medical Center in New York City.

“We are there assembled, ready to go. But sometimes the wisest course of action is delay,” said Quinn Capers IV, MD, of the Ohio State University College of Medicine in Columbus. “This I think gives you confidence in this group of patients, who are facing a very high in-hospital mortality, that [by] giving pause, you’re not necessarily doing something to their disservice, or at least you can think about it a little bit more.”

Still, he cautioned, “Most of us are pretty reticent to change our practice based on one study, especially a study with 500 patients.” Other trials are ongoing to decisively answer the question in non-STEMI.

In COACT, secondary endpoints likewise showed no advantage to quick catheterization, including 90-day survival with good cerebral performance or mild or moderate disability, myocardial injury, duration of catecholamine support, markers of shock, recurrence of ventricular tachycardia, duration of mechanical ventilation, major bleeding, occurrence of acute kidney injury, need for renal-replacement therapy, and neurologic status at discharge from the ICU.

The exception was time to temperature targeted for hypothermia, which was longer with immediate angiography (5.4 vs 4.7 hours).

A key reason for the lack of benefit of early coronary intervention could be that most deaths were from neurologic complications, not cardiac causes, Lemkes suggested.

“We really need to focus on that,” he said. While trials haven’t proven early hypothermia improves outcomes in these patients either, delaying it is not a good thing, he added.

The trial included 552 out-of-hospital cardiac arrest patients with an initial shockable rhythm who were unconscious after resuscitation to spontaneous circulation. Along with STEMI patients, those in shock or with an obvious non-coronary cause of arrest were excluded. Cardiac arrest was witnessed for 76% to 79% of patients.

They were randomized to coronary angiography as soon as possible (started within 2 hours of resuscitation, median 0.8 hr) or after neurologic recovery (typically after ICU discharge, median 119.9 hrs). All were to get PCI if indicated, and 33.0% of the immediate and 24.2% of the delayed group did.

Only 3.4% and 7.6%, respectively, were found to have an acute thrombotic obstruction.

“We are not saying from this trial to walk away from all of these patients,” Capers noted. “You had some data that those over [age] 70, those with a history of coronary artery disease might be more likely to be those with active lesions.”

The treatment appeared to be more beneficial in subgroup analyses by age (P=0.007 for interaction) and history of coronary artery disease (P=0.009 for interaction).

“It would really be wonderful to figure out who those patients are [who are going to need PCI], so the other 60% of patients you don’t have to take to the cath lab,” said ACC session discussion panelist Christopher Nielsen, MD, of the Medical University of South Carolina in Charleston.

Lemkes agreed that it would be most important to identify those with acute thrombotic obstruction, the group who needs rapid PCI.

While his group is looking at the ECG as a possible predictor, he acknowledged that the study may be too small to dig into predictors, and that it may prove a challenge even pooling in the other ongoing trials, ACCESS and DISCO.

Another reason for the findings may have been the selection criteria, cautioned an accompanying editorial by Benjamin Abella, MD, MPhil, of the University of Pennsylvania and David Gaieski, MD, of Jefferson Medical College, both in Philadelphia.

“If the current trial had used more specific inclusion criteria, it could have enriched the cohort for patients with probable coronary disease, and very different outcomes might have resulted,” they wrote. Along with age and prior coronary disease, “the trial design did not take into account clinical context, such as acute chest pain or other symptoms of coronary ischemia, which are known to often precede a cardiac arrest that has a coronary cause.”