The TOMAHAWK study examined whether immediate coronary angiography in survivors of out-of-hospital cardiac arrest (OHCA) and no ST-segment elevation is beneficial with regard to all-cause mortality at 30 days, compared with initial intensive care assessment with delayed/selective angiography.

This large-scale, randomized controlled trial involving non-STEMI OHCA patients showed that early angiography (with PCI if indicated) fell just short of a statistically important increase in death (p=0.06). Obstructive CAD was found more often, and PCI performed more often, in the delayed angiography group. This suggests the hazards of invasive therapies outweigh the benefits in this unique patient group.

The TOMAHAWK results extend those of COACT, another trial of early angiography in OHCA patients, but importantly COACT evaluated only patients with shockable rhythms, Desch et al, noted during the TOMAHAWK presentation. In the TOMAHAWK trail, all patients without ST-segment elevation were eligible, and in fact, only a minority of patients were found to have underlying culprit coronary artery lesions. Since many arrests resulted from causes other than acute MI, angiography proved to have little value in improving outcomes. In many cases, neurologic damage may obviate any benefit of early cardiac diagnosis.

Read an interview with author Steffen Desch, MD, who presented TOMAHAWK in the third Hot Line session of the European Society of Cardiology (ESC) Congress 2021. The study was simultaneously published online in the New England Journal of Medicine.