Without ST-Segment Elevation, Immediate Angiography After Out-of-Hospital Cardiac Arrest Is Unnecessary
By Walter Alexander
VIRTUAL -- September 1, 2021 -- For most patients who have out-of-hospital cardiac arrest, immediate cardiac catheterisation is not necessary, according to a study presented at the Virtual 2021 European Society of Cardiology (ESC) Congress.
“Take your time and first evaluate the clinical course,” recommended Steffen Desch, MD, Heart Center, Leipzig, Germany.
Whereas acute myocardial infarction (MI) is the cause of cardiac arrest in up to a third of patients surviving out-of-hospital cardiac arrest without ST-segment elevation, the usefulness and timing of coronary angiography are uncertain. Although ESC guidelines recommend considering delayed angiography among haemodynamically stable patients without ST-segment elevation, the guidelines also state that possible benefits of an early invasive approach will be addressed in ongoing trials.
Dr. Desch noted that possible harms of an early invasive approach include delayed diagnosis and treatment for aetiologies other than MI, as well as known risks of procedural complications (ie, renal damage, reperfusion injury, stent thrombosis, bleeding, and cerebral damage).
The TOMAHAWK study enrolled 554 patients who had out-of-hospital cardiac arrest. The patients were randomised 1:1 to immediate coronary angiography or initial intensive-care-unit assessment with delayed angiography, if indicated. The primary endpoint was all-cause mortality at 30 days.
In the immediate-angiography group, 54.0% of patients died. In the delayed/selective-angiography group, the rate was 46.0% (hazard ratio = 1.28; 95% confidence interval [CI], 1.00-1.63; P = .058, nonsignificant). No prespecified subgroups had significant differences, including those with shockable versus nonshockable rhythms.
However, for the secondary composite endpoint of all-cause death or severe neurological deficit at 30 days, a significant increase was seen in the immediate-angiography group (relative risk = 1.16; 95% CI, 1.002-1.340).
COACT, a prior trial assessing early angiography in patients with out-of-hospital cardiac arrest, also found no benefit, but this trial was restricted to patients with shockable rhythms.
“TOMAHAWK results help to avoid unnecessary immediate cardiac catheterisation after out-of-hospital cardiac arrest,” said Dr. Desch. “In TOMAHAWK, the higher rate of death or severe neurological deficit in the immediate-angiography group is only hypothesis-generating. However, the results of the trial suggest that patients without a significant coronary lesion as the trigger of cardiac arrest do not benefit from an invasive approach and might even be harmed.”
[Presentation title: Trial Does Not Support Early Coronary Angiography in Cardiac Arrest Without ST Elevation]