A recent review of percutaneous coronary interventions (PCI) performed in the state of Washington shows that although femoral procedures outnumber radial cases 20 to 1, the newer approach reduces overall bleeding, especially in higher-risk groups. The findings were published online January 2, 2013, ahead of print in the American Heart Journal. 

Researchers led by Charles Maynard, PhD, of the University of Washington (Seattle, WA), analyzed data on 23,599 patients who underwent a first PCI at 30 centers in Washington between 2010 and 2011, comparing patient characteristics and complication rates according to use of the transradial vs. transfemoral approach.

Transradial Approach Uncommon

Transradial PCI was used in only about 5% of patients, with the rate increasing from 3.8% in 2010 to 6.1% in 2011. The prevalence of the transradial approach varied widely from center to center; 8 hospitals performed less than 1% of cases transradially, while 3 hospitals performed more than 10% via this approach. At 2 centers, the proportion rose to about a quarter of procedures in the second year.

Overall, bleeding occurred in 2.2% of patients, but the rate for the transradial group was less than half that of the femoral group (1.0% vs. 2.3%; P = 0.006).

Logistic regression analysis identified several predictors of increased bleeding risk, the most important being:

• Acute indication for PCI
• Female sex
• Age ≥ 75 years
• Renal failure (creatinine > 2.0 mg/dL)
• Nonwhite race
• History of congestive heart failure

Women, who were more likely to experience bleeding than men (3.9% vs. 1.6%; P < 0.001), showed a greater reduction in bleeding with transradial vs. femoral access (1.4% vs. 4.0%; P = 0.013 in women compared with 0.9% vs. 1.6%; P = 0.12 in men). Rates of access site bleeding and in-hospital death were also lower with transradial PCI for both women and men, but in neither case did the differences reach statistical significance.

After adjustment for demographic and clinical variables, overall bleeding rates were 19% lower with the transradial approach—16% lower in men and 19% lower in women. Older patients and those with renal dysfunction showed relative reductions of 17% and 20%, respectively, with transradial PCI (table 1).

Table 1. Adjusted Likelihood of Bleeding by Risk Group^a

^a All differences are statistically significant except for elevated creatinine.

According to the authors, the Washington State results combined with the current literature “suggest that [radial] PCI compared with [femoral] PCI appears to be safer, more effective, more patient centered, and possibly more equitable given that women appear to have less bleeding with [transradial] PCI.” They note that the latter proposition is currently being evaluated in the randomized SAFE-PCI for Women trial.

Dr. Maynard and colleagues point out that “these results were obtained during a period of early adoption of [transradial] PCI in Washington State” and thus represent a learning curve. Future results when the procedure is more widely adopted may be “very different,” they add.

Little Incentive to Switch

In a telephone interview with TCTMD, James Tift Mann III, MD, of Wake Heart and Vascular Associates (Raleigh, NC), said the study reiterates what is already known about the safety of transradial procedures. Moreover, he noted, the figures on transradial usage are only slightly below those recently reported by the National Cardiovascular Data Registry Cath-PCI Registry.

Perhaps the 2.2% incidence of bleeding is the most important finding, Dr. Mann said, in that it helps explain the relatively poor penetration of transradial access in the US interventional community. This low rate “reflects the results of bleeding-avoidance strategies that have been incorporated over the past decade,” he noted. At that level of safety, “many operators—and particularly low-volume operators in the United States—feel less compelled to learn the radial procedure, which has a fairly steep learning curve.”

Furthermore, he said, the study illustrates the ‘transradial paradox:’ The technique is used less frequently in the very individuals who could benefit the most, such as women and acute and older patients. These types of patients tend to be more susceptible to bleeding complications and thus would clearly profit from transradial access, Dr. Mann observed, but because the procedure may be more difficult to perform in them, especially under time constraints, operators are less comfortable choosing the radial approach.

To Dr. Mann, a notable defect of the paper is its failure to clarify what qualified as access site complications, since the seriousness of these events depends on how they are defined. “This is an area that’s undergoing scrutiny in larger studies like RIVAL and RIFLE, for example, where we’re trying to sort out the causes of bleeding complications associated with catheterization,” he said. “It raises the whole issue of whether or not bleeding at the access site is truly the most important cause of mortality associated with catheterization procedures.”

As to whether the study results might incrementally advance the cause of transradial PCI in the United States, Dr. Mann was skeptical, noting that much stronger, prospective studies favoring the radial approach have had little impact on adoption.

“In the United States, low operator volume is always going to be an issue,” he added, noting that operators performing few cases are “very reluctant to undertake the learning curve for transradial procedures.”

Study Details

Transradial and transfemoral patients were similar with regard to age, gender, race, and most comorbidities, although a higher percentage of transradial patients had diabetes or peripheral vascular disease. Notably, however, patients with STEMI or other acute conditions such as cardiogenic shock or prehospital cardiac arrest were more likely to undergo transfemoral PCI. Transfemoral patients were also more likely to receive glycoprotein IIb/IIIa inhibitors or bivalirudin.

Related Stories:

• Initial Transradial Learning Curve Not Harmful to Overall PCI Safety
• Transradial PCI Associated with Lower Costs, Shorter Hospital Stay Than Femoral Route
• Transradial PCI Reduces Bleeding in High-Risk ACS Patients