Background: While left ventricular (LV) venting reduces LV distension in cardiogenic shock patients on venoarterial extracorporeal membrane oxygenation (VA-ECMO), it may also amplify risk of acute brain injury (ABI). We investigated the hypothesis that LV venting is associated with increased risk of ABI. We also compared ABI risk of the two most common LV venting strategies, percutaneous microaxial flow pump (mAFP) and intra-aortic balloon pump (IABP). Methods: The Extracorporeal Life Support Organization registry was queried for patients on peripheral VA-ECMO for cardiogenic shock (2013-2024). ABI was defined as hypoxic-ischemic brain injury, ischemic stroke, or intracranial hemorrhage. Secondary outcome was hospital mortality. We compared no LV venting with 1) LV venting, 2) mAFP, and 3) IABP using multivariable logistic regression. To compare ABI risk of mAFP vs. IABP, propensity score matching was performed. Results: Of 13,276 patients (median age=58.2, 69.9% male), 1,456 (11.0%) received LV venting (65.5% mAFP and 29.9% IABP), and 525 (4.0%) had ABI. After multivariable regression, LV-vented patients had increased odds of ABI (adjusted odds ratio (aOR)=1.76, 95% CI=1.29, 2.37, p<0.001) but no difference in mortality (aOR=1.08, 95% CI=0.91-1.28, p=0.39) compared to non-LV-vented patients. In the propensity-matched cohort of IABP (n=231) vs. mAFP (n=231) patients, there was no significant difference in odds of ABI (aOR=1.35, 95%CI=0.69-2.71, p=0.39) or mortality (aOR=0.88, 95%CI=0.58-1.31, p=0.52). Conclusions: LV venting was associated with increased odds of ABI but not mortality in patients receiving peripheral VA-ECMO for cardiogenic shock. There was no difference in odds of ABI or mortality for IABP vs. mAFP patients.

DB reports consulting for LivaNova. He has been on the medical advisory boards for Medtronic, Inspira, Cellenkos and HBOX Therapies. He is the President-elect of the Extracorporeal Life Support Organization (ELSO) and the Chair of the Board of the International ECMO Network (ECMONet), and he writes for UpToDate. The other authors have no conflicts of interest to disclose.

Dr. Keller is funded by NIH (5K08HL14332) and DARPA (HR001124S0024). Dr. Cho is supported by NIH (1K23HL157610; 1R21NS135045) and DARPA (HR001124S0024).

I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.

Yes

The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

This retrospective observational cohort study was approved by the Johns Hopkins Hospital Institutional Review Board with a waiver of informed consent (IRB00216321).

I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals.

Yes

I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).

Yes

I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable.

Yes

The data used in this study were obtained from the Extracorporeal Life Support Organization (ELSO) registry, a comprehensive international database of patients receiving extracorporeal life support. Access to the ELSO registry data is available upon request and subject to approval by the ELSO Scientific Oversight Committee. For more information on accessing the registry data, including submission guidelines and requirements, please visit the ELSO website at www.elso.org.