Radial vs femoral access for percutaneous coronary intervention: temporal trends and outcomes in the USA

Background and Aims Radial access site for percutaneous coronary intervention (PCI) is recommended by clinical practice guidelines because of superior outcomes compared with femoral access site. Historically, the adoption of radial access site in the USA has lagged behind much of the rest of the world, but contemporary data on access site selection across the spectrum of clinical presentations and its association with outcomes are lacking.Methods A retrospective cohort study from the National Cardiovascular Data Registry's CathPCI Registry was conducted including PCIs performed between 1 January 2013 and 30 June 2022. The comparative safety of radial vs femoral access site for PCI was evaluated with instrumental variable analysis, a technique that can be used to support causal inference, exploiting operator variation in access site preferences as the instrumental variable.Results Overall, 6 658 479 PCI procedures were performed during the study period, of which 40.4% (n = 2 690 355) were performed via radial access site, increasing from 20.3% in 2013 to 57.5% in 2022. This increase was seen in all geographic regions and across the full spectrum of presentations, with the largest relative increase seen in patients with ST-elevation myocardial infarction. Overall, 2 420 805 PCIs met inclusion criteria for the comparative safety analysis. In instrumental variable analyses, radial access site was associated with lower in-hospital mortality [absolute risk difference (ARD) -.15%, 95% confidence interval (CI) -.20 to -.10], major access site bleeding (ARD -.64%, 95% CI -.68 to -.60), and other major vascular complications (ARD -.21%, 95% CI -.23 to -.18) but a higher risk of ischaemic stroke (ARD .05%, 95% CI .03-.08). There was no association with the falsification endpoint of gastrointestinal or genitourinary bleeding (ARD .00%, 95% CI -.03-.03).Conclusions Over the past decade, use of radial access site for PCI has increased 2.8-fold in the USA and now represents the dominant form of access site across all procedural indications. Based on instrumental variable analyses, PCI with radial access site had lower rates of in-hospital mortality, major access site bleeding, and other major vascular complications compared with femoral access site but a slightly higher risk of ischaemic stroke in contemporary practice.