Ultrasound-Guided Transfemoral Access for Coronary Procedures: A Pooled Learning Curve Analysis From the FAUST and UNIVERSAL Trials

BACKGROUND: The learning curve for new operators performing ultrasound-guided transfemoral access (TFA) remains uncertain. METHODS: We performed a pooled analysis of the FAUST (Femoral Arterial Access With Ultrasound Trial) and UNIVERSAL (Routine Ultrasound Guidance for Vascular Access for Cardiac Procedures) trials, both multicenter randomized controlled trials of 1:1 ultrasound-guided versus non-ultrasound-guided TFA for coronary procedures. Outcomes included the composite of major bleeding or vascular complications and successful common femoral artery cannulation. Participants were stratified by the operators' accrued case volume. We used adjusted repeated-measurement logistic regression, with random intercepts for operator clustering, for comparison against the non-ultrasound-guided TFA group and to model the learning curve. RESULTS: The FAUST and UNIVERSAL trials randomized a total of 1624 patients, of which 810 were randomized to non-ultrasound-guided TFA and 814 to ultrasound-guided TFA (cases 1-10, 391; 11-20, 183; and >20, 240). Participants who had operators who performed >20 ultrasound-guided TFAs had a decreased risk for the primary end point (5/240 [2.1%] versus 64/810 [7.9%]; adjusted odds ratio, 0.26 [95% CI, 0.09-0.61]) compared with non-ultrasound-guided TFA. Operators who performed >20 ultrasound-guided procedures had increased odds of successfully cannulating the common femoral artery (224/246 [91.1%] versus 327/382 [85.6%]; adjusted odds ratio, 1.76 [95% CI, 1.08-2.89]) compared with non-ultrasound-guided TFA. The learning curve plots demonstrated growing competence with increasing accrued cases. CONCLUSIONS: New operators should perform at least 20 ultrasound-guided TFA to decrease access site complications and increase proper cannulation compared with non-ultrasound-guided TFA. Additional accrued cases may lead to increased proficiency. Training programs should consider these findings in the transradial era.