Outcomes and Institutional Variation in Arterial Access Among Patients With AMI and Cardiogenic Shock Undergoing PCI

Background: Contemporary data comparing the outcomes of transradial access (TRA) vs transfemoral access (TFA) among patients presenting with acute myocardial infarction and cardiogenic shock (AMI-CS) undergoing percutaneous coronary intervention (PCI) are limited. Objectives: This study examines in-hospital outcomes and institutional variation among patients with AMI-CS undergoing TRA-PCI vs TFA-PCI. Methods: Patients admitted with AMI-CS from the NCDR CathPCI registry between April 2018 and June 2021 were included. Multivariable logistic regression and inverse probability weighting models were used to assess the association between access site and in-hospital outcomes. A falsification analysis using non-access site–related bleeding was performed. Results: Among 35,944 patients with AMI-CS undergoing PCI, 25.6% were performed with TRA. The proportion of TRA-PCI increased over the study period (22.0% in the second quarter of 2018 vs 29.1% in the second quarter of 2021; P-trend <0.001). Significant institutional-level variability in the use of TRA-PCI was also observed: 20.9% of all sites using TRA in <2% of PCIs (low utilization) vs 1.9% of all sites using TRA in >80% of PCIs (high utilization). Patients undergoing TRA-PCI had a significantly lower adjusted incidence of major bleeding (odds ratio [OR]: 0.71; 95% confidence interval [CI]: 0.67-0.76), mortality (OR: 0.73; 95% CI: 0.69-0.78), vascular complications (OR: 0.67; 95% CI: 0.54-0.84), and new dialysis (OR: 0.86; 95% CI: 0.77-0.97). There was no difference in non-access site related bleeding (OR: 0.93; 95% CI: 0.84-1.03). Sensitivity analyses revealed similar benefit with TRA-PCI among patients without arterial cross-over. There were no significant interactions observed between TRA-PCI with mechanical circulatory support and in-hospital outcomes. Conclusions: In this large nationwide contemporary analysis of patients with AMI-CS, about quarter of PCIs were performed via TRA with wide variability across US institutions. TRA-PCI was associated with significantly lower incidence of in-hospital major bleeding, mortality, vascular complications, and new dialysis. This benefit was observed irrespective of mechanical circulatory support use.