Transradial cardiac catheterization: Is femoral access obsolete?☆☆☆★★★

See related article on page 430.

Invasive diagnosis of cardiac diseases requires access to the arterial circulation and cardiac chambers for angiography and hemodynamic assessment. In the early days of cardiac catheterization direct techniques, including transthoracic, suprasternal, and transbronchial punctures, were used. Pioneers such as Drs Earl Wood and colleagues at the Mayo Clinic helped establish the hemodynamic basis of congenital and valvular lesions. Retrograde transluminal cardiac catheterization increased applicability and decreased the invasive nature of cardiac catheterization. Originally performed via open brachial arteriotomy, selective coronary angiography as developed by Dr Mason Sones and colleagues allowed direct visualization of the coronary arteries. Subsequently the percutaneous arterial puncture technique of Seldinger allowed even easier and rapid access to the arterial circulation while avoiding open tissue dissection. The use of preformed Judkins-type catheters popularized the femoral arterial approach, which has since become the preferred approach in most laboratories.

Although radial artery cannulation for aortography was reported in the 1940s,1 only recently has attention been directed to the radial artery as a potential access site for cardiac catheterization. Numerous publications, mostly European, have demonstrated the feasibility of the technique both for diagnostic and interventional procedures.2, 3 In this issue of the Journal, Cooper et al4 report results of a randomized comparison of radial and femoral arterial access sites on quality of life and costs after cardiac catheterization. Although patients with acute coronary syndromes were excluded from enrollment, patients were otherwise well matched and representative of patients undergoing cardiac catheterization in most U.S. laboratories. Both femoral and radial access sites were highly successful, with only one patient in each group crossing over to the alternate access site from catheterization. Importantly, all measures of quality of life and patient comfort significantly favored the radial access group, and patients overwhelmingly preferred transradial catheterization, with its opportunity for immediate ambulation, over the traditional femoral route. Transradial cardiac catheterization was associated with a markedly shorter median length of hospital stay (3.6 vs 10.4 hours, P < .0001) and accordingly lead to a 10% to 15% cost reduction.

Previous studies have demonstrated the feasibility, efficacy, and safety of performing percutaneous interventional procedures via the radial access site, including balloon angioplasty, stent deployment, and even rotational atherectomy. In comparison to the brachial artery, the radial artery has a number of advantages for retrograde cardiac catheterization. It is superficial, easily compressible, and most importantly is not an end artery. As long as ulnar artery patency is present, no major complications have been reported as a result of a radial artery occlusion. In contrast, brachial artery occlusion can be a catastrophic complication and is a surgical emergency. Because no major nerves or veins are in the anatomic vicinity of the radial artery pulse over the radial styloid, the likelihood of neuropathies or arteriovenous fistulas is extremely small. Infrequently encountered anatomic anomalies that can make brachial procedures problematic do not interfere with passing catheters from the radial artery.5 In comparison to the femoral artery, bed rest is simply not necessary after radial catheterization, and uncomfortable groin compression or expensive closure devices are not needed. Radial catheterization allows for true outpatient catheterization and, potentially, stenting. Back pain, hematomas, and vascular surgical complications are virtually eliminated. For obese patients, the radial artery makes a convenient and safe access site.

With the above considerations in mind, the question “what does radial artery access have to offer?” should be reworded to “why are we still using the femoral artery?” Although radial access is popular in Europe, it has been slow to gain acceptance in North America. Part of this is because of the learning curve. Achieving access in the radial artery is technically more challenging and time consuming, especially during the initial phases of learning. Spasm and discomfort will undoubtedly be encountered and at times may be severe. The technique described by Cooper et al is a good one to minimize spasm. Perhaps the most important reason radial artery access has been slow to catch on has been that many laboratories prefer to perform same-sitting interventional procedures and as a consequence must be ready for anything. The femoral artery allows passage of large caliber guiding catheters and adjunctive devices such as balloon pumps to allow virtually any type of percutaneous interventional procedure. Recent technical advances in miniaturization of diagnostic catheters to 4F and 5F catheters along with very low profile stent technologies should address many of these concerns. Surgical colleagues are currently evaluating the radial artery as a potential conduit for aortocoronary bypass, and this fact should be taken into consideration if the on-site surgical program is harvesting radial arteries.6 Fortunately, radial artery occlusion is rare after catheterization as long as sheaths are removed soon after the procedure. Late occlusions are very rare,7 but careful performance of a preprocedure Allen’s test is mandatory.

In our experience, diagnostic catheterization and percutaneous interventional procedures can be performed safely, effectively, and comfortably in a wide variety of patients. Spasm and failure to access are most likely to occur in smaller patients and those with sever peripheral vascular disease. Concerns over increased radiation exposure8 to primary operators can be addressed by positioning the arm along the side of the patient. With the arm at the patient’s side, laboratories and operators accustomed to femoral access can perform catheterization with almost no equipment repositioning. We prefer to remove the sheath and apply direct pressure after diagnostic and interventional procedures. Nursing units experienced with the postprocedure care of cardiac patients will have no trouble caring for these patients.

Patients who have undergone cardiac catheterization from both the leg or the wrist almost without exception strongly prefer the wrist. Whether the radial artery will represent the next major revolution in access sites for cardiac catheterization remains to be determined. Cardiologists who are committed to providing patient-oriented care should take note because the question may quickly change from whether radial artery catheterization will supplant femoral artery catheterization to when .