There is increasing interest in using the radial artery in the wrist, rather than the femoral artery in the groin, for passing slender catheters into the heart during angioplasty and stenting, largely because it is safer and more comfortable for patients. But when launching a program to train cardiologists in the radial technique, cardiac catheterization laboratories should be prepared to face logistical challenges for a substantial period of time, according to a study presented at the Society for Cardiovascular Angiography and Interventions (SCAI) 33rd Annual Scientific Sessions.

The study found that even after more than 50 patients had undergone transradial percutaneous coronary intervention (PCI) at a university medical center, average procedure times were longer and procedural success rates lower when compared with previous experience using the femoral artery.

"Our study showed that it's going to take a lot more than 50 cases before everything goes as smooth as silk," said the study's senior author Michael Lim, M.D., director of the cardiac catheterization laboratory and interim cardiology director at St. Louis University. "There's good reason for doing transradial PCI, and we need to keep that in mind. The commitment has to be there from the beginning."

To evaluate the effect on the catheterization laboratory of launching an outpatient, transradial PCI program, Dr. Lim and his colleagues analyzed data from the first 53 patients in whom a radial artery puncture was used to access the arterial system, comparing them with a matched group who had earlier undergone PCI using femoral artery access.

They found that transradial access was successful in 87 percent of patients. It took an average of 7.57 minutes to establish access using the radial artery, as compared to 4.17 minutes in the femoral group (p=.002 ). The PCI procedure was successful in 83 percent of patients with radial artery access, vs. 96 percent of patients in the femoral access group (p=0.15). Fluoroscopy time-when interventional cardiologists are using x-rays and contrast dye to guide angioplasty balloons and stents through the arteries and perform PCI-was 10.01 minutes on average in the radial access group, as compared with 4.07 minutes in the femoral access group (p=.003). There were no vascular complications in either group.

Researchers concluded that in a teaching hospital, the learning curve for adoption of radial techniques is significantly longer than might be expected. "It is absolutely worth it. Patients who have undergone catheterization procedures using the wrist are much happier," Dr. Lim said. "I truly believe in transradial PCI, but the reward is long-term."

SCAI Press Release, May 05, 2010.