Background: Ischemic cardiac arrest represents a challenge for optimal emergency revascularization therapy. A percutaneous left ventricular assist device (LVAD) may be beneficial. Objective: To determine the effect of a percutaneous LVAD during cardiac arrest without chest compressions and to assess the effect of fluid loading. Design: Totally, 16 pigs randomized to either conventional or intensive fluid with LVAD support during ventricular fibrillation (VF). Setting: Acute experimental trial with pigs under general anesthesia. Subjects: Farm pigs of both sexes. Interventions: After randomization for fluid infusion, VF was induced by balloon occlusion of the proximal left anterior descending artery. LVAD and fluid were started after VF had been induced. Measurements: Brain, kidney, myocardial tissue perfusion, and cardiac index were measured with the microsphere injection technique at baseline, 3, and 15 minutes. Additional hemodynamic monitoring continued until 30 minutes. Main results: At 15 minutes, vital organ perfusion was maintained without significant differences between the two groups. Mean cardiac index at 3 minutes of VF was 1.2 L
min
1
m2 (29% of baseline, p < 0.05). Mean perfusion at 3 minutes was 65% in the brain and 74% in the myocardium compared with baseline (p < 0.05), then remained unchanged during the initial 15 minutes. At 30 minutes, LVAD function was sustained in 11 of 16 animals (8 of 8 intensified fluid vs. 3 of 8 conventional fluid) and was associated with intensified fluid loading (p < 0.001). Conclusions: During VF, a percutaneous LVAD may sustain vital organ perfusion. A potential clinical role of the device during cardiac arrest has yet to be established. (Crit Care Med 2009; 37: 1365–1372)