Impact of OHCA on outcome in cardiogenic shock patients receiving mechanical circulatory support

Background Approximately half of the infarct-related shock (AMICS) patients who receive mechanical circulatory support (MCS) present with an out-of-hospital cardiac arrest (OHCA). Preceding OHCA complicates AMICS characterisation, as hypotension and elevated lactate levels in these patients may not solely be attributed to reduced cardiac function. Moreover, OHCA presumably affects (neurological) outcome. Purpose To understand the impact of preceding OHCA in patients receiving MCS by investigating baseline characteristics and 30-day mortality in OHCA and non-OHCA patients. Methods This real-world multicentre study analyses data from the Netherlands Heart Registration PCI-Registry to describe AMICS patients who underwent PCI and received MCS from 2017-2021. Baseline characteristics and 30-day mortality were compared between (1) non-OHCA patients, (2) patients with OHCA followed by return of spontaneous circulation (ROSC), and (3) patients requiring extracorporeal resuscitation (eCPR). Results This study included 241 patients, of whom 51% non-OHCA, 25% OHCA+ROSC and 24% requiring eCPR. Non-OHCA patients were older compared to ROSC and eCPR patients (63.4 vs. 59.4 vs. 52.1 years old, p<0.01), Also, non-OHCA patients more often had a prior coronary event (34% vs. 29% vs. 7%, p<0.01), more frequently suffered multivessel disease (78% vs. 48% vs. 54%, p<0.01) and had lower admission lactate levels (4.5 vs. 8.4 vs. 13.0 mmol/L, p<0.01). The 30-day mortality rates were comparable among non-OHCA, ROSC and eCPR patients (61% vs. 65% vs. 61%, p=0.87). Conclusion Despite patient characteristic differences and contrary to expectations, OHCA was not associated with 30-day mortality in MCS receiving patients. Especially in eCPR patients, this may indicate adequate patient selection. Figure 1.KM-Curve