RTC Analysis Confirms Lower Mortality for Radial Access Versus Femoral Access in ACS Patients

August 29, 2022—The European Society of Cardiology (ESC) announced the presentation of data from a Radial Trialists’ Collaboration (RTC) study showing that radial artery access for coronary angiography or percutaneous coronary intervention (PCI) is associated with lower risks of all-cause death and bleeding compared with femoral access.

Study investigator Giuseppe Gargiulo, MD, of Federico II University Hospital in Naples, Italy, commented in the ESC press release, “Thirty years after the first radial access interventional coronary procedure on 14 August 1992, our study provides, for the first time, adequate power and solid evidence from high-quality, multicenter, randomized trials that the use of radial instead of femoral access is associated with reduced all-cause mortality. The benefit accrues early (ie, within 10 days) after PCI and is maintained up to 30-day follow-up.”

The late-breaking research was presented in a Hot Line session at the 2022 ESC Congress held August 26-29 in Barcelona, Spain. The study was published by Dr. Gargiulo et al online in Circulation.

As observed in the ESC press release, European and American guidelines endorse the preferential use of a transradial approach (TRA) over a transfemoral approach (TFA) in patients requiring coronary catheterization. TRA has been associated with a lower incidence of access site–related bleeding and vascular complications compared with TFA. In some studies—but not others, noted the press release—TRA was associated with a mortality benefit; however, none of the analyses were adequately powered for individual endpoints including mortality. Aggregate-data meta-analyses have been conducted but lack granularity to adjust for confounders or identify subgroups that may particularly benefit or be harmed.

According to ESC, this was the first large individual patient-level data meta-analysis of high-quality, multicenter, randomized clinical trials to investigate the impact of radial versus femoral artery access for coronary angiography or PCI on mortality and major bleeding.

Investigators from the RTC obtained individual patient data from trials comparing TRA versus TFA among patients undergoing coronary angiography with or without PCI.

The meta-analysis included pooled data from seven trials, with a total of 21,600 patients. Of these, 10,775 were randomized to TRA, and 10,825 were randomized to TFA. The median age of patients was 63.9 years, 31.9% were women, 95% presented with acute coronary syndrome, and 75.2% underwent PCI.

The study’s primary outcome was all-cause mortality at 30 days, and the coprimary outcome was major bleeding at 30 days. The primary analysis was conducted based on the intention-to-treat cohort.

The RTC investigators found that the incidence of all-cause death was lower in the TRA group versus the TFA group (1.6% vs 2.1%; hazard ratio; 0.77; 95% CI, 0.63-0.95; P = .012). Major bleeding was also significantly reduced with TRA versus TFA (1.5% vs 2.7%; odds ratio, 0.55; 95% CI, 0.45-0.67; P < .001).

The survival benefit was confirmed in the per-protocol, as-treated, PCI, acute coronary syndrome, and myocardial infarction cohorts. The effects of TRA were also consistent across the majority of prespecified subgroups, and the findings indicated that patients with baseline anemia might have a greater mortality benefit compared to those without anemia.

Additionally, the investigators reported that in a multivariable model, TRA was independently associated with a significant 24% relative risk reduction of 30-day all-cause mortality and a 51% reduction of major bleeding. Mediation analysis showed that the benefit of TRA on mortality was only marginally driven by the prevention of major bleeding.

“Our study conclusively indicates a favorable prognostic impact of TRA over TFA in terms of survival,” stated Dr. Gargiulo in the ESC press release. “It should be noted that the advantages of TRA for mortality, major bleeding, and other clinical outcomes primarily apply to acute coronary syndrome patients, who represented approximately 95% of our study population, and cannot be fully extended to elective patients undergoing coronary angiography with or without PCI.”

Dr. Gargiulo concluded, “This analysis provides definitive evidence that TRA should be considered the gold standard for patients undergoing cardiac catheterization with or without PCI, supporting the ‘radial-first’ approach.”