Early use of levosimendan to improve survival and neurological outcomes after cardiac arrest with myocardial dysfunction: a protocol for a randomized controlled trial

Introduction Post-cardiac arrest myocardial dysfunction (PAMD) is a major contributor to early death (within 72 hours) following return of spontaneous circulation (ROSC). Levosimendan, a calcium-sensitizing inotrope with vasodilatory and mitochondrial-protective properties, offers a potential therapeutic strategy by increasing cardiac output, improving organ perfusion, and attenuating mitochondrial ischemia-reperfusion injury. While experimental evidence suggests multi-organ benefits in cardiac arrest (CA), robust clinical data are lacking. Methods and analysis This exploratory, partially blinded, randomized, placebo-controlled trial will enroll 60 comatose CA patients with PAMD across three centers in China. Within 180 minutes after ROSC, eligible participants will be randomized (1:1) to receive either intravenous levosimendan (0.05–0.2 μg/kg/min for 24 hours) or volume-matched saline placebo; the assigned infusion will begin within 6 hours after ROSC. The primary outcome is 30-day all-cause mortality, interpreted within an exploratory signal-generating framework. Secondary outcomes explore 30-day neurological recovery assessed by the Cerebral Performance Category (CPC) and Modified Rankin Scale (mRS), along with cardiac function and hemodynamic stability during the first week post-resuscitation. Discussion This exploratory trial is designed to align early levosimendan infusion (within 6 hours post-ROSC) with its pharmacokinetics to cover the anticipated nadir of myocardial dysfunction. By targeting a homogeneous cohort with witnessed arrest, rapid ROSC (<60 min), and LVEF <40%, the trial focuses on patients with potentially reversible injury who may benefit most. The findings will provide preliminary evidence on efficacy and safety to inform a definitive Phase III trial. Clinical Trial Registration https://clinicaltrials.gov/study/NCT05956431 , ClinicalTrials.gov NCT05956431. Registered on 21 July 2023.