Outcome in Patients with Out-of-Hospital Cardiac Arrest without ST-Segment Elevation and Revascularization During the Index Catheterization – A subanalysis of the TOMAHAWK trial

A. Freund (Leipzig)¹, I. Akin (Mannheim)², M. R. Preusch (Heidelberg)³, C. Skurk (Berlin)⁴, G. Fürnau (Dessau-Roßlau)⁵, J. Pöss (Leipzig)¹, M. Roßberg (Leipzig)¹, T. Thevathasan (Berlin)⁴, H. Thiele (Leipzig)¹, S. Desch (Leipzig)^1
1Herzzentrum Leipzig - Universität Leipzig Klinik für Innere Medizin/Kardiologie Leipzig, Deutschland; ²Universitätsklinikum Mannheim GmbH I. Medizinische Klinik Mannheim, Deutschland; ³Universitätsklinikum Heidelberg Klinik für Innere Med. III, Kardiologie, Angiologie u. Pneumologie Heidelberg, Deutschland; ⁴Charité - Universitätsmedizin Berlin CC 11: Med. Klinik für Kardiologie Berlin, Deutschland; ⁵Städtisches Klinikum Dessau Klinik für Innere Medizin II Dessau-Roßlau, Deutschland

Background
Myocardial infarction is a frequent cause of out-of-hospital cardiac arrest (OHCA), even in the absence of ST-segment elevation. The TOMAHAWK trial showed no superiority of an early coronary angiography (CAG) compared to a delayed/selective approach in patients after OHCA of possible coronary origin but without ST-segment elevation on post-resuscitation electrocardiogram. However, less than 50% presented with a possible culprit lesion. Whether a better patient selection would result into a benefit of early CAG remains unclear.

Objectives
To evaluate the effect of immediate CAG compared to delayed CAG in OHCA patients without ST-elevation after return of spontaneous resuscitation in whom percutaneous coronary intervention (PCI) was performed during the index procedure.

Methods
Patients of the TOMAHAWK (Angiography after Out-of-Hospital Cardiac Arrest without ST-Segment Elevation) trial with PCI during the index procedure were included using the results of the pre-specified angiography core lab analyses. The primary endpoint was 30-day all-cause mortality. Secondary endpoints included severe neurological deficit, stroke, myocardial infarction, acute renal failure requiring renal replacement therapy, major bleeding and levels of peak troponin and creatinine within 30 days. Further, all-cause death at 12 months was analysed.

Results
A total of 155 patients were included. All-cause death at 30 days occurred in 42 of 87 patients (48.3%) in the immediate CAG group and in 23 of 68 (33.8%) patients in the delayed CAG group (HR 1.63, 95% CI 0.97-2.75, p=0.055) (Figure 1). The combined endpoint of all-cause mortality and severe neurological deficit, as well as peak levels of creatinine were higher in the immediate CAG group, whereas peak troponin T levels were higher in the delayed CAG group. No differences were seen with respect to other secondary endpoints. At 12 months, mortality in the immediate CAG group was higher compared to the delayed CAG group (53 of 87 patients (60.9%) versus 26 of 68 patients (38.2%); HR 1.91, 95% CI 1.18-3.09) (Figure 2).


Conclusion
In patients with OHCA and no ST elevation, early CAG has no benefit with respect to early mortality compared to delayed CAG, even when revascularisation is considered indicated and performed during the index procedure. There is even evidence of a worse outcome at 12 months.