Immediate Platelet Inhibition Strategy for Comatose Out-of-Hospital Cardiac Arrest Survivors Undergoing Percutaneous Coronary Intervention and Mild Therapeutic Hypothermia

Background: Comatose survivors of out-of-hospital cardiac arrest (OHCA) undergoing percutaneous coronary intervention (PCI) and target temperature management (TTM) are at increased risk of stent thrombosis (ST), partly due to delayed platelet inhibition even with more potent P2Y₁₂ agents. We hypothesized that periprocedural cangrelor would induce immediate platelet inhibition, bridging the “P2Y₁₂ inhibition gap”. Methods: In our pilot study, we randomized 30 comatose OHCA patients undergoing PCI and TTM (32–34 °C) into cangrelor and control groups. Both groups received unfractioned heparin, acetylsalicylic acid, and ticagrelor via enteral tube. The cangrelor group also received an intravenous bolus of cangrelor followed by a 4 h infusion. Platelet inhibition was measured using VerifyNow^® and Multiplate^® ADP at baseline and 1, 3, 5, and 8 h post PCI. Results: Patient characteristics did not differ between groups. VerifyNow^® showed significantly decreased platelet reactivity with cangrelor at 1 h (30 vs. 221 PRU; p < 0.001) and 3 h (24 vs. 180 PRU; p < 0.001), with differences at 5 and 8 h. Similarly, the proportion of patients with high on-treatment platelet reactivity (HPR) in the cangrelor group was significantly lower at 1 h (0% vs. 67%; p < 0.001) and 3 h (0% vs. 47%; p = 0.007). Multiplate^® ADP was also decreased at 1 h (14 vs. 48 U; p < 0.001) and 3 h (11 vs. 42 U; p = 0.001), with no difference at 5 and 8 h. The occurrence of bleeding events was similar in both groups. Conclusions: Cangrelor safely induced immediate and profound platelet inhibition. We observed no significant drug–drug interaction with ticagrelor.