By Timothy C. Lee, MD, MPH, FACP, FACC, FSCAI, FASNC, FAHA
Alabama Heart and Vascular, PC
Alabama Heart and Vascular, PC
Catheterizations through the radial artery have several advantages:
1. Patient comfort is significantly improved. Because the entry site is at the wrist, patients are able to sit up and walk immediately after their procedure whereas patients having their procedures via the femoral artery approach will often require up to six hours of bed rest. As result, there are fewer issues with back discomfort and patients are able to eat comfortably after their procedure.
2. Patients who are scheduled for same day discharge can be discharged at an earlier time period than if their procedure was performed through the femoral approach since the post-procedure recovery is typically shorter than with the femoral approach.
3. The radial approach is safer than the femoral approach for the majority of patients undergoing cardiac catheterization. Because the artery is smaller and very close to the skin, important bleeding is significantly reduced compared to the femoral approach.
Women are at particular risk for bleeding and vascular complications after percutaneous coronary intervention (PCI). Women also have smaller radial arteries than men making radial PCI potentially more challenging.
While a transradial approach can potentially reduce these complications, this technique has never been prospectively studied in women. However, arecent clinical trial conducted exclusively in women suggests that an initial strategy of using the radial artery in the arm as the entry point for cardiac catheterization or percutaneous coronary intervention (PCI) in women has potential for reducing bleeding complications.
“The SAFE [Study of Access Site for Enhancement]-PCI for Women Trial suggests an initial strategy of radial access is reasonable and may be preferred in women,” said lead author Sunil Rao, MD, Duke University School of Medicine, Durham, North Carolina.
Dr. Rao presented the findings on October 29 at the 2013 Transcatheter Cardiovascular Therapeutics meeting (TCT).
“While women are at higher bleeding risk, they have smaller radial arteries that are more prone to spasm, which has been implicated as a major cause of transradial procedure failure,” he said. “The role of radial access in women is unclear.”
The first-ever randomized trial to compare interventional access strategies in women found distinct advantages with radial access over the more traditional femoral route, with a trend toward a reduction of bleeding and vascular complications by about 60 percent through radial access, according to results from the SAFE-PCI trial presented Oct. 29 as part of Transcatheter Cardiovascular Therapeutics (TCT) 2013 in San Francisco.
The Study of Access site For Enhancement of PCI for Women (SAFE-PCI for Women) trial prospectively compared radial access and femoral access in 1,787 women undergoing elective percutaneous coronary intervention (PCI), urgent PCI or diagnostic catheterization with possible PCI. Results showed no difference between the radial and femoral groups in 30-day death, vascular complications or unplanned revascularizations.
In the PCI group, patients who underwent radial PCI experienced reduced bleeding and complication rates compared to the femoral cohort (1.2% vs. 2.9%), though this difference proved statistically insignificant. In the broader group—which included patients receiving diagnostic cath—radial access did indeed show a significant reduction in bleeding and complication rates compared to the femoral approach (0.6% vs. 1.7%, p=0.03).
Further, about six percent of women had to convert to femoral access, primarily because of radial artery spasm. Women generally preferred radial access, with 71.9 percent saying they preferred radial access for the next procedure versus 23.5 percent who preferred femoral access.
The trial did not reach its planned enrollment due to early termination. After 1,120 patients were randomized, review by the Data and Safety Monitoring Board (DSMB) showed that the primary efficacy event rate was markedly lower than expected. The DSMB recommended termination of the trial; however, no harm was noted in either arm and the steering committee voted to continue the study until enrollment in a quality-of-life substudy was complete.
Based on the SAFE-PCI trial findings, experts indicate that radial PCI is a viable initial approach in women undergoing cardiac catheterization though operators should be prepared for cross-over to femoral access.
Although some experts agree, "The study provides evidence, albeit not conclusive, for greater efficacy with radial access in women.”
The biggest factor driving the decision to use the radial artery is the physician performing the procedure. The procedure can be more challenging technically, and the physician must have enough experience to feel comfortable with radial procedures. Many physicians are more comfortable with the femoral approach, and will therefore recommend it alone.
There are a growing number of physicians in the United States, however, who prefer to use the radial artery as their default approach. There are also many physicians who use the radial approach in selective situations where the femoral approach may be more complicated, such as in obese patients or patients with obstructions in the blood vessels supplying the lower extremity. The femoral approach may be selected for patients in whom preservation of the radial artery is essential, such as patients requiring dialysis fistulas.