Randomized clinical trials (RCTs) suggest benefits for the transradial approach to percutaneous coronary intervention (PCI) for ST-elevation myocardial infarction (STEMI). However, transradial PCI may delay reperfusion, leading to its avoidance. We sought to quantify the delay in reperfusion from transradial PCI (“transradial delay”) that would need to be introduced to offset the potential mortality benefit of transradial PCI, compared with transfemoral, observed in RCTs.

We developed a decision-analytic model to compare transfemoral and transradial PCI in STEMI. Thirty-day mortality rates were estimated by pooling STEMI patients from 2 RCTs comparing transfemoral and transradial PCI. We projected the impact of transradial delay using estimates of the increase in mortality associated with door-to-balloon time delays. Sensitivity analyses were performed to understand the impact of uncertainty in assumptions.

In the base case, a transradial delay of 83.0 minutes was needed to offset the mortality benefit of transradial PCI. When the mortality benefit of transradial PCI was one-quarter that observed in RCTs, the delay associated with equivalent mortality was 20.9 minutes. In probabilistic sensitivity analyses, transradial PCI was preferred over transfemoral PCI in 97.5% of simulations when transradial delay was 30 minutes and in 79.0% of simulations when delay was 60 minutes.

A substantial transradial delay is required to eliminate even a fraction of the mortality benefit observed with transradial PCI in RCTs. Results were robust to changing multiple assumptions and have implications for operators reluctant to transition to transradial PCI in STEMI because of concern for delaying reperfusion.