Radial Artery Spasm: Pick the Right Cocktail and Relax

Many clinicians across the world have adopted the transradial approach for coronary angiography and percutaneous coronary intervention (PCI).^1,2 Reduced vascular complications, early ambulation, patient satisfaction, and reduced procedural costs are among the reasons the transradial approach is becoming increasingly popular.^1-6 However, radial artery spasm (RAS) is a common complication of the transradial approach, leading to patient discomfort, procedure failure, and a significant barrier to wide-scale adoption of the technique.^7,8

In this issue of the Journal, Carrillo et al report their experience9 with two common intra-arterial (IA) vasodilator regimens used during the transradial approach for PCI. The authors conducted a study where 30 consecutive patients requiring PCI were randomized 1:1 to receive IA administration. They performed intravascular ultrasound (IVUS) at 5 minutes after sheath insertion and 1 minute after administration of the vasodilator regimen. They used an automatic border detection algorithm to calculate the intraluminal volume of the radial artery. Both regimens resulted in significant vasodilation as assessed by arterial lumen volume and radial artery diameter. The authors also noted no significant difference in radial artery volume or diameter increase in patients with previous transradial intervention when compared to patients without previous transradial intervention. They concluded that the administration of either of the vasodilator regimens produced the same results, and using IVUS with this specific algorithm is a precise and sensitive way to evaluate radial artery volume.

The reported incidence of RAS varies from 2% to 34%.^3,5,7,8 Various stimuli can cause radial artery smooth muscle cells to contract and spasm.¹ Prior studies have demonstrated that the predominant mechanism of RAS is mediated by activation of the ∝-1 adrenoreceptors.¹⁰ Prophylactic IA administration of vasodilating and spasmolytic agents has been shown to significantly reduce RAS.^1,3,5,7,8 Medications such as phentolamine,⁸ nicorandil,⁷ nitroprusside,¹¹ nitroglycerin, and verapamil have shown to be effective vasodilator treatments.^3,5,7,8,11 These medications, either alone or in combination as a “cocktail,” can induce a significant increase in radial artery volume and diameter.^3,7,8 In one study, the rate of RAS was reduced from 20.4% to 4% with IA administration of nitroglycerin alone or by adding verapamil.³ The negative inotropic effects of verapamil make it an unsuitable agent in patients with impaired left ventricular function or conduction disturbances.^3,8 With this in mind, Chen et al demonstrated that there was no significant difference in preventing RAS between administration of 100 µg nitroglycerin versus 100 µg of nitroglycerin plus 1.25 mg of verapamil (p = 0.804).³ Utilization of hydrophilic sheaths, downsizing sheath caliber,¹² patient sedation,¹ and education will also lead to a lower incidence of RAS.

Injury to the radial artery after transradial approach has been reported in many studies,^13-15 making it an unsuitable conduit for bypass surgery and subsequent same arm transradial approach. Injuries such as occlusion, intimal tears, medial dissections, and chronic intima-media thickening have been measured with the use of IVUS¹⁴ and optical coherence tomography¹⁵ in these patients. Although techniques to limit injury, such as small sheath/radial artery ratio, anticoagulation, and immediate sheath removal, have been identified,^13-15 further studies are needed to assess the long-term patency of the radial artery after transradial access. However, the findings of this study offer an alternative view that radial artery volume and the ability to vasodilate are not impacted by repeat access.

The study from Carrillo and colleagues showed significant increase in arterial luminal volume with administration of nitroglycerin plus verapamil or verapamil alone. Unlike many other studies, they attempted to objectively measure the impact of vasodilator therapy on the radial artery. An increase in radial artery size is associated with lower rates of RAS.¹⁶ Despite prophylactic vasodilator treatment, radial artery spasm remains an important procedural limitation of the transradial approach.^1,7,8 The transradial community continues to await the right cocktail so the radial artery and operators can relax.

References

1. Caputo RP, Tremmel JA, Rao S, et al. Transradial arterial access for coronary and peripheral procedures: executive summary by the transradial committee of the SCAI. Catheter Cardiovasc Interv. 2011 May 4. doi: 10.1002/ccd.23052. (Epub ahead of print).
2. Schussler JM. Effectiveness and safety of transradial artery access for cardiac catheterization. Proc (Bayl Univ Med Cent). 2011;24(3):205-209.
3. Chen CW, Lin CL, Lin TK, Lin CD. A simple and effective regimen for prevention of radial artery spasm during coronary catheterization. Cardiology. 2006;105(1):43-47.
4. Hildick-Smith DJ, Lowe MD, Walsh JT, et al. Coronary angiography from the radial artery — experience, complications and limitations. Int J Cardiol. 1998;64(3):231-239.
5. Kiemeneij F, Vajifdar BU, Eccleshall SC, Laarman G, Slagboom T, van der Wieken R. Evaluation of a spasmolytic cocktail to prevent radial artery spasm during coronary procedures. Catheter Cardiovasc Interv. 2003;58(3):281-284.
6. Pristipino C, Trani C, Nazzaro MS, et al. Major improvement of percutaneous cardiovascular procedure outcomes with radial artery catheterization: results from the PREVAIL study. Heart. 2009;95(6):476-482.
7. Kim SH, Kim EJ, Cheon WS, et al. Comparative study of nicorandil and a spasmolytic cocktail in preventing radial artery spasm during transradial coronary angiography. Int J Cardiol. 2007;120(3):325-330.
8. Ruiz-Salmeron RJ, Mora R, Masotti M, Betriu A. Assessment of the efficacy of phentolamine to prevent radial artery spasm during cardiac catheterization procedures: a randomized study comparing phentolamine vs. verapamil. Catheter Cardiovasc Interv. 2005;66(2):192-198.
9. Carrillo X, Fernandez-Nofrerias E, Ciompi F, et al. Changes in radial artery volume assessed using intravascular ultrasound: a comparison of two vasodilator regimens in transradial coronary interventions. J Invasive Cardiol. 2011;23(10):401-404.
10. He GW, Yang CQ. Characteristics of adrenoceptors in the human radial artery: clinical implications. J Thorac Cardiovasc Surg. 1998;115(5):1136-1141.
11. Coppola J, Patel T, Kwan T, et al. Nitroglycerin, nitroprusside, or both, in preventing radial artery spasm during transradial artery catheterization. J Invasive Cardiol. 2006;18(4):155-158.
12. Koga S, Ikeda S, Futagawa K, et al. The use of a hydrophilic-coated catheter during transradial cardiac catheterization is associated with a low incidence of radial artery spasm. Int J Cardiol. 2004;96(2):255-258.
13. Sakai H, Ikeda S, Harada T, et al. Limitations of successive transradial approach in the same arm: the Japanese experience. Catheter Cardiovasc Interv. 2001;54(2):204-208.
14. Wakeyama T, Ogawa H, Iida H, et al. Intima-media thickening of the radial artery after transradial intervention. An intravascular ultrasound study. J Am Coll Cardiol. 2003;41(7):1109-1114.
15. Yonetsu T, Kakuta T, Lee T, et al. Assessment of acute injuries and chronic intimal thickening of the radial artery after transradial coronary intervention by optical coherence tomography. Eur Heart J. 2010;31(13):1608-1615.
16. Ruiz-Salmeron RJ, Mora R, Velez-Gimon M, et al. [Radial artery spasm in transradial cardiac catheterization. Assessment of factors related to its occurrence, and of its consequences during follow-up]. Rev Esp Cardiol. 2005;58(5):504-511.

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From the University of Illinois – Chicago and the Jesse Brown VA Medical Center, Chicago, Illinois.
Disclosure: The authors have completed and returned the ICMJE Form for Disclosure of Potential Conflicts of Interest. Dr. Shroff reports consulting for Terumo Medical, Abiomed and the Medicines Company. Dr. Shivaraju reports no disclosures.
Address for correspondence: Adhir Shroff, MD, MPH, FACC, FSCAI, Associate Professor of Medicine, University of Illinois – Chicago and Jesse Brown VA Medical Center, 840 S Wood St, MC 715, Chicago, IL 60607. Email: arshroff@uic.edu