Systems approach shows promise for out-of-hospital CAD

Survival with favorable quality of life improved among patients with refractory out-of-hospital ventricular fibrillation (VF)/ventricular tachycardia (VT) cardiac arrest when they were quickly taken to a cardiac catheterization laboratory (CCL) for extracorporeal life support (ECLS) and revascularization, as opposed to being treated with prolonged resuscitation efforts at the scene of their heart attack, according to new research.

“Complex but treatable coronary artery disease (CAD) was prevalent in patients with refractory out-of hospital VF/VT cardiac arrest who also met criteria for continuing resuscitation in the CCL,” wrote lead author Demetris Yannopoulos, with the University of Minnesota School of Medicine in Minneapolis, and coauthors. “A system of care including rapid transport of patients with ongoing refractory VF/VT to the hospital, where ECLS and reperfusion can be provided, and improved functionally favorable survival.”

The research was published online Aug. 21 in the Journal of the American College of Cardiology.

The study cohort comprised 62 patients with out-of-hospital cardiac arrest who were conveyed by emergency medical services (EMS) to the hospital between December 1, 2015, and December 1, 2016. Forty-seven of the transported patients were admitted to the hospital.  The majority were white men, and their mean age was 58 +10 years.

Nineteen of the 47 patients died within 5 +2 days. The researchers found five factors were associated with survival:

1. Earlier arrival of first responders after the 911 call.
2. Lower lactic acid levels.
3. Intermittent or sustained return of spontaneous circulation (ROSC) before arrival at the CCL.
4. Higher end-tidal carbon dioxide upon reaching the CCL.
5. The presence of coronary artery disease as a reversible cause.

The historical comparison group employed was a group of 170 patients, of whom 73 percent were men and 78 percent were white. These individuals also had experienced cardiac arrest at home and, as governed by the EMS protocol at the time, had resuscitation efforts continued at the scene for 45 to 60 minutes, until ROSC was accomplished or the patient died. In this historical comparison group, 15.3 percent of patients survived and were discharged from the hospital.

In contrast, the intervention group, which experienced prompt EMS transport and reperfusion therapy, had a 42 percent of patients survived to hospital discharge, and they had functionally favorable profiles.

“As the clinical availability of ECLS increases, use of this technology to treat patients with refractory cardiac arrest is likely to increase,” the authors wrote.