Transradial Cardiac Catheterization Technique

Updated: Jan 07, 2020
  • Author: David H Adler, MD, FACC, FSCAI; Chief Editor: Eric H Yang, MD  more...
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Approach Considerations

The left or right radial artery can be used for cardiac catheterization. The standard equipment setup in most catheterization laboratories facilitates right radial artery access, which tends to be used more frequently.

In a 2019 systematic scoping review (inception to September 2018) of MEDLINE and EMBASE comprising 19 publications with 4,212 participants that evaluated distal transradial access for cardiac catheterization, the investigators found an overall 95.4% success rate and a 2.4% complication rate. [68]  There was no significant difference in complication rate between distal transradial access and conventional transradial access, with the primary complication being bleeding/hematoma. Radial occlusion occurred in 1.7% of patients who underwent transradial access. [68]



Transradial Catheterization

Under sterile conditions, the radial artery is accessed with a 20- to 21-gauge needle, and a 5F-6F sheath is advanced into the artery over a wire using the Seldinger technique.

Vasodilators (usually verapamil and nitroglycerin) are administered to reduce radial artery spasm. [69, 70]

Hydrophilic sheaths are generally used to minimize trauma to the radial artery. An anticoagulant (usually unfractionated heparin [UFH] or bivalirudin) is given to prevent radial artery thrombosis. [71]  A 2017 systematic review and meta-analysis found that observational studies suggest a benefit of higher-dose vs lower-dose UFH in reducing post-transradial cardiac catherization radial artery occlusion, but the findings were less clear in randomized trials. [72]  In a 2019 single-center study that evaluated radial artery occlusion in 686 patients who underwent diagnostic cardiac catherization and received either 100 IU/kg UFH (high dose) or 50 IU/kg UFH (standard dose), investigators found an independent association between lower rates of radial artery occlusion and high-dose UFH. [73] Only 36 of the 686 patients (5.2%) experienced radial artery occlusion as detected by vascular Doppler ultrasonography. [73]

A guidewire is then advanced from the radial artery to the ascending aorta.

Catheters are advanced over the guidewire and used for coronary angiography and/or coronary intervention. Specialized catheters shaped to aid in engaging the coronary arteries from the transradial approach have been developed, although traditional coronary catheters can also be used.

After the procedure, the sheath is removed and pressure is held over the arteriotomy site to achieve hemostasis. Several devices have been developed to assist in maintaining pressure on the wrist; most are bands that allow easy modification of hemostatic pressure.