Joseph Lewis, MD, Interventional Cardiology
The Chester County Hospital and Health System
Published: February 20, 2012
Catheterization of the heart's arteries (a.k.a. coronary arteries) has traditionally been performed via a large, easily accessible vessel in the groin called the femoral artery. After applying a local anesthetic, an interventional cardiologist places a small (2mm) tube in the femoral artery, then advances various pre-shaped catheters into the coronary arteries to perform a diagnostic angiogram (to see whether or not the arteries are blocked) or an intervention (i.e. use of angioplasty and placement of a stent to open a blocked artery).
In the mid-1990s, doctors started to perform these procedures utilizing a vessel in the wrist called the radial artery and generally referred to as Transradial Access (TRA). Unlike the groin approach, TRA had the advantage of allowing patients to get back on their feet more quickly following the procedure, and was a step toward making the procedure more "minimally invasive." At that time in the US, TRA was not adopted by the majority of interventionalists because the procedure was more technically challenging for the operators, in part related to the design of the equipment. There is clearly a learning curve for the physicians using this technique but as they continue to gain experience, their outcomes improve.
The use of the procedure continued to grow worldwide, and it became apparent that it was safer compared with the femoral approach, primarily because of a lower chance of bleeding from the TRA access site. It is now resurging in this country. For the last three years, the percentage of both diagnostic and therapeutic cases has steadily risen. In 2007, only 1.3% of interventions in the US were performed by TRA compared with 29% worldwide. In 2011, that figure was more than 10% nationally and, in various markets, it was much higher. It is important to realize that some physicians use mostly a radial approach while others do not. The percentage of radial cases performed for a particular hospital represents the aggregate of radial use by its various interventionalists. Also, not all patients are considered candidates for the radial approach for various anatomic and clinical reasons.
There are a number of potential advantages to the radial approach:
1. Early ambulation (walking). As suggested above, a few hours of bed rest is necessary after a femoral approach but not so with TRA. This can be particularly helpful in patients with back problems.
2. Uninterrupted medicinal therapy. It has been demonstrated that the procedure can be safely performed in patients who take blood thinners, with little or no interruption of therapy, a clear advantage considering the higher risk of bleeding with the femoral approach.
3. Convenience. In a recent international survey, more than 90% of patients preferred the radial approach compared with the femoral.*
One area that holds particular promise for the wrist access is in treatment of patients having acute heart attacks. Several recent research trials have shown reduced complications (mostly reduced occurrence of bleeding) and even improved survival when the use of angioplasty/stent was performed by an experienced transradial interventionalist compared with the groin approach. It is important that the physician be thoroughly experienced with TRA, as any delay in this type of procedure for a patient in the throes of a heart attack would have obvious negative consequences.
In summary, transradial access is rapidly gaining popularity in this country among patients and physicians. It has proven to be not only more convenient and comfortable for patients but also actually safer. I believe most would agree this truly represents progress and surely we will continue to see this trend continue.
* Survey (called R.I.V.A.L.) co-conducted by Population Health Research Institute.
This article was published as part of the Daily Local News Medical Column series which appears every Monday. It has been reprinted by permission of the Daily Local News.