Study information

Recruiting status

Study completed

Recruitment start





Clinical Trials Registration



Guideline relevant study

DZHK Funding

EUR 1.749.861


Operative contact
Main study centre - Anne Freund, MD

Studienzentren/Kontakt (PDF)

Immediate unselected coronary angiography versus delayed triage in survivors of out-of-hospital cardiac arrest without ST-segment elevation (TOMAHAWK-DZHK4)

A study to compare an unselected coronary angiography versus a delayed triage in survivors of out-of-hospital cardiac arrest without ST-segment elevation (TOMAHAWK)

If someone has suffered from cardiac arrest and can be successfully reanimated, he will be taken to hospital immediately. Statistically, cardiac arrest is attributed to a heart attack in about 50 percent of affected patients; the other 50 percent are victims of an accident or seriously ill patients. During a heart attack, there is usually constriction or occlusion of the coronary vessels, whereby cardiac muscle cells die. As a consequence, patients often suffer from severe cardiac arrhythmias and cardiac arrest may occur. Swiftly opening the constricted vessels using a cardiac catheter is the method of choice to prevent further damage to the heart.

Recognising a heart attack as the cause of cardiac arrest in patients who have been reanimated and who are usually unconscious is often not so simple, especially not when no typical elevations of the so-called ST segment are detected in the ECG. The aim of the study is to research whether patients who have survived cardiac arrest with a possible, but initially not confirmed, heart attack as the cause would benefit from an immediate cardiac catheterisation in terms of mortality, or whether it might be better to initially conduct further diagnostics and - if necessary - only perform a cardiac catheterisation at a later time. Patients with ST segment elevation myocardial infarction will not be included in the study, because it is likely that, for them, opening the occluded vessel immediately increases their chance of survival.

With the results of their research, the principal investigators of the study want to provide treating doctors with more security in their choice of treatment options, which could increase the chance of survival for the patients concerned.


Coronary Angiography After Out-of-Hospital Cardiac Arrest Without ST-Segment Elevation One-Year Outcomes of a Randomized Clinical Trial. Desch, S. et al. JAMA Cardiol. 2023;8(9):827-834. doi:10.1001/jamacardio.2023.2264

Angiography after Out-of-Hospital Cardiac Arrest without ST-Segment Elevation.Desch, S. et al., for the TOMAHAWK Investigators. New England Journal of Medicine, 29 August 2021.

Immediate Unselected Coronary Angiography Versus Delayed Triage in Survivors of out-of-Hospital Cardiac Arrest without St-Segment Elevation: Design and Rationale of the Tomahawk Trial. Desch, S. et al. Am Heart J 2019, 20-29, (2018).

More publications here

Principal Investigators

Principal investigator: Steffen Desch (Lübeck und Leipzig), Co-PI: Holger Thiele (Leipzig)

Press releases and news

Immediate angiograms not always necessary after cardiac arrest (Study TOMAHAWK-DZHK4)

Immediate angiograms are not necessary, and can even cause worse outcomes, after a cardiac arrest...

Better Decision-Making in the Management of Acute Myocardial Infarction and Cardiac Arrest

Two new clinical studies run by the German Centre for Cardiovascular Research (DZHK) aim to optimise...

Study recruitment is available in these cities

The map only displays recruitment locations within Germany.