RIVAL Compares Radial and Femoral Access for Coronary Interventions

April 4, 2011—The American College of Cardiology (ACC) announced that investigators in the largest randomized trial comparing radial access and femoral access for coronary angiography and intervention found that radial access led to reduced rates of vascular complications while maintaining similar angioplasty success rates as femoral access.

The RIVAL study was presented at the ACC's 60th annual scientific session in New Orleans. The study was also published online ahead of print in The Lancet at the time of presentation.

The ACC stated that the trial also found that radial access did not reduce the primary outcome measure of death, heart attack, stroke, and noncoronary artery bypass graft (non-CABG) surgery–related major bleeding compared to femoral access in the overall study population. However, radial access did lead to reductions in the primary outcome measure in patients who underwent the procedure at hospitals that conducted a high volume of radial procedures.

According to the ACC, the RIVAL trial was designed to help determine the optimal access site for coronary angiography and intervention in patients with acute coronary syndromes. Previous data have shown that radial access results in fewer bleeding complications than femoral access, but this information has only come from observational studies and small, randomized trials. In addition, there has been concern that radial access could be associated with a greater angioplasty procedural failure rate.

During the past 2 decades, femoral access has been used in approximately 95% of coronary angiography and interventional procedures in the United States. However, the data from the previous observational studies suggest that the radial artery is associated with a 50% to 60% reduction in the odds of major bleeding, which is strongly associated with a reduction in mortality. Thus, the study RIVAL investigators believed this alternate route might be an attractive option for interventional cardiologists.

“It is increasingly recognized that preventing bleeding complications may be just as important as preventing recurrent ischemic complications in patients with acute coronary syndromes,” commented coprincipal investigator Sanjit Jolly, MD. “Our hypothesis was that radial access would reduce access site bleeding with preserved angioplasty efficacy.”

As detailed by the ACC, the international, multicenter RIVAL study randomized 7,021 patients to receive either radial access (n = 3,507) or femoral access (n = 3,514).

The primary outcome measure was the incidence of death, heart attack, stroke, or non-CABG–related major bleeding at 30 days. Other outcome measures included angioplasty procedural success and major vascular access site complications at 48 hours and 30 days postprocedure.

The investigators found that radial access and femoral access performed similarly with regard to the primary outcome measure, with 3.7% and 4% of patients, respectively, experiencing death, heart attack, stroke, or non-CABG–related major bleeding at 30 days (hazard ratio [HR], 0.92; 95% confidence interval [CI], 0.72–1.17; P = .5). Both groups also showed similar rates of angioplasty success, at 95.4% of patients in the radial group and 95.2% of patients in the femoral cohort (HR, 1.01; 95% CI, 0.95–1.07; P = .83).

Radial access performed better when comparing major vascular complications. The investigators reported that 1.4% of patients in the radial cohort experienced death, heart attack, stroke, or non-CABG–related major bleeding at 30 day, compared to 3.7% of patients in the femoral group (HR, 0.37; 95% CI, 0.27–0.52; P < .001). Radial access also yielded better results in patients with ST-segment elevation heart attack for the primary outcome measure and for mortality. Furthermore, radial access had better outcomes than femoral access at institutions that performed a high volume of radial procedures (the converse was not seen at institutions performing many femoral access procedures). In addition, all access site major bleeds occurred at the femoral arterial access site.

“The results of the RIVAL trial show that both access sites are safe and effective,” Dr. Jolly said. “The reduction in vascular access complications may be a reason for interventional cardiologists to use radial access. Furthermore, the effectiveness of the radial approach may improve with greater expertise and procedural volume.”