Timing and predictors of definite stent thrombosis in comatose survivors of out-of-hospital cardiac arrest undergoing percutaneous coronary intervention and therapeutic hypothermia (ST-OHCA study)

Background: Incidence of stent thrombosis (ST) in comatose survivors of out-of-hospital cardiac arrest (OHCA) undergoing immediate percutaneous coronary intervention (PCI) and therapeutic hypothermia (TH) varies considerably, from 2.7% to 31.2%, in retrospective studies.Aims: We aimed to investigate occurrence, timing and predictors of definite ST.Methods: We prospectively investigated consecutive comatose survivors of OHCA with presumed cardiac aetiology undergoing immediate PCI with drug-eluting stents (DES) and TH targeted at 32-34 degrees C admitted between August 2016 and July 2021. Repeat coronary angiography (CAG) was performed if ST was sus-pected and systematically between day 8-12 in the absence of clinical signs. All deceased patients under-went autopsy and histopathological analysis.Results: Among 362 comatose survivors of OHCA, immediate PCI with stenting was performed in 169 patients (47%). Since 18 patients did not complete follow-up, 151 patients were ultimately enrolled in ST analysis. Definite ST was confirmed in 29 patients (19.2%; 95% confidence interval [CI]: 12.9%-25.6%) either by CAG (n=18) or autopsy (n=11). ST occurred within 3 days in 62% and presented with at least one clinical sign in 79%. Survival with good neurological recovery was observed in 17% of patients with ST and in 60% of patients without ST (p<0.001). Independent predictors of ST were longer prehospital resuscitation, lower arterial pH and increased creatinine on admission.Conclusions: The incidence of definite ST in comatose survivors of OHCA undergoing immediate PCI and TH targeted at 32-34 degrees C is substantial (19.2%) and significantly higher than in other PCI subsets despite systematic use of contemporary DES and anticoagulation/antiplatelet treatment.