Coronary angiography in out-of-hospital cardiac arrest : why, when and for whom?

Study I. A national observational retrospective study, evaluating the effect on survival of early coronary angiography vs. no early coronary angiography in witnessed, unconscious OHCA patients with shockable rhythm and without ST-elevation on the first ECG. Unadjusted 30-day survival in the early-angiography group was 65%, compared with 52% in the no-early-angiography group. The adjusted OR for 30-day survival was 1.42 for early angiography (95% CI 1.00-2.02, p=0.048). The adjusted HR for one-year survival was 1.35 for early angiography (95% CI 1.04-1.77, p=0.03). Study II. An open-label, prospective, randomized, national multicenter clinical study in OHCA patients carried out to assess feasibility and safety aspects in a strategy of coronary angiography within 120 minutes from first medical contact versus coronary angiography potentially performed at a later stage. Among 79 randomized patients (from 2015 to 2017), 39 were randomized to immediate coronary angiography and 40 to standard-of-care treatment. The median time from EMS arrival to coronary angiography was 135 minutes in the immediate-angiography group. A culprit lesion was found in 14/38 (36.8 %) patients randomized to immediate coronary angiography and PCI was performed in all these patients. In patients randomized to standard of care treatment 6/40 (15%) underwent coronary angiography before the stipulated three days. Study III. A retrospective, descriptive, single-center study, assessing the use of Focused Cardiac Ultrasound (FOCUS) in cardiac-arrest patients with ROSC and without ST-elevations on the ECG. In total, FOCUS was performed in 237 (182 OHCA and 55 in-hospital cardiac arrest) patients. FOCUS findings had an impact on management and led to further immediate diagnostic measures in 52 (21.9%) patients. Study IV. A sub-study of Study II carried out to compare post-resuscitation myocardial function in the two randomized groups. In the immediate angiography group, median left-ventricle ejection fraction (LVEF) at 24 hours was 47% (Q1-Q3; 30-55) compared with 46% (Q1-Q3; 35-55) in the standard-of-care group. The peak Troponin-T level during the first 24 hours was 362 ng/L (Q1-Q3; 174-2020) in the immediate-angiography group compared with 377 ng/L (Q1-Q3;205-1078) in the standard-of-care group. Conclusions: In a Swedish OHCA population with shockable rhythm without ST-elevation, early coronary angiography may be associated with improved short- and long-term survival. Randomizing OHCA patients without ST-elevation to a strategy of immediate coronary angiography was feasible. No significant safety issues were observed. No differences in post-resuscitation myocardial dysfunction parameters between the two groups were found. Post-resuscitation assessment could include FOCUS as an adjunctive diagnostic measure shortly after ROSC