TOMAHAWK trial – clinical outcomes from 1-year follow-up

By Dr Jonathan Shurlock
Edited by Dr Ahmed El-Medany

The TOMAHAWK Investigators, led by Dr Steffen Desch, have described clinical outcomes at 1 year for individuals presenting with out-of-hospital cardiac arrest (OHCA) with a presumed cardiac cause in a much-anticipated follow-up to the original TOMAHAWK trial. The original trial randomised 554 patients presenting with OHCA, without ST-segment elevation to immediate angiography or initial intensive care assessment with delayed or selective angiography.

In the present study, the authors undertook a follow up secondary analysis of the original participant group and included all 554 patients. Clinical outcomes were assessed, with a primary outcome measure of survival at 1 year. Secondary outcome measures included severe neurological deficit, myocardial infarction, and re-hospitalization for congestive heart failure.

Participants were randomised to immediate (n=281) or delayed/selective angiography (n=273). Median age was 70 years (IQR, 60-78 years). All-cause mortality at 1 year was not significantly different between groups (60.8% immediate versus 54.3% delayed/selective angiography, Hazard ratio 1.25; 95%CI, 0.99-1.57; p= 0.05). The authors report this relationship as a trend towards increased mortality with immediate angiography. There were no differences in secondary outcome measures between groups.

As an interesting note aside from the primary outcome measures, 55.5% of presenting patients were in a shockable rhythm. This deviates significantly from population level data which shows that only around 1 in 4 OHCA present in a shockable rhythm. This may well simply reflect those who survive to hospital admission.

The study adds additional data to the complex decision-making process in patients presenting with OHCA. At present the available data does not support immediate coronary angiography for all patients. With this ongoing outcome data, in addition to other risk stratification work such as MIRACLE-2, cardiologists are increasingly well informed by a solid evidence base to support decision making in these challenging situations.

Read the full study here: