Need for prophylactic application of verapamil in transradial coronary procedures: a randomized trial. The VITRIOL (is Verapamil In TransRadial Interventions OmittabLe?) trial

Abstract

Background: Verapamil is traditionally applied prophylactically in transradial procedures to prevent radial artery spasm. However, verapamil may have side effects and is contraindicated in some clinical settings.

Methods and results: During an investigator-initiated, randomized, double-blind trial, we evaluated the need for preventive verapamil administration. After vascular access was established, patients received either 5 mg verapamil (n=297) or placebo (n=294). We compared the rate of access site conversions as primary end point using a superiority margin of 5%. Occurrence of code breaks (composite of conversions and unplanned use of verapamil), overall verapamil use, procedural and fluoroscopic times, contrast volume, and subjective pain were investigated as secondary end points. The rate of access site conversions was not different in the 2 arms (placebo 1.7% versus verapamil 0.7%, P=0.28, difference 1.0%, 95% CI for the difference -1.1% to 3.3%). Proportion of code breaks was similar in the 2 groups (3.4% versus 1.3%, P=0.11), whereas overall verapamil use was markedly lower in the placebo arm (2.0% versus 100%, P<0.0001). Procedural time (median [IQR] 16.0 minutes [9.0 to 30.0 minutes] versus 17.0 minutes [10.0 to 31.0 minutes], P=0.37), fluoroscopic time (4.4 minutes [2.1 to 9.6 minutes] versus 4.8 minutes [2.4 to 10.7 minutes], P=0.28), contrast volume (72.5 mL [48.0 to 146.0 mL] versus 75.5 mL [47.0 to 156.5 mL], P=0.74), and pain score (P for trend=0.12) were comparable in the 2 groups.

Conclusions: The preventive use of verapamil may be unnecessary for transradial procedures. The omission of prophylactic verapamil may not only reduce the rate of potential complications related to the drug but also allow the safe extension of the transradial method to those with contraindications to verapamil.

Clinical trial registration url: http://www.clinicaltrials.gov. Unique identifier: NCT01402427.

Keywords: coronary angiography; drug policy; percutaneous coronary intervention; transradial; vasodilator; verapamil.

Figures

Figure 1.

Study algorithm. A total of 591 patients were randomized to receive either 5 mg verapamil diluted with 0.9% w/v saline or placebo (0.9% w/v saline alone) intra‐arterially. For details, see text. IA indicates intra‐arterial; P, placebo arm; V, verapamil arm.

Figure 2.

Primary study end point. There was no significant increase in the conversion rate of the placebo arm (Fisher's exact test, placebo 5/294=1.7% vs verapamil 2/297=0.7%, P=0.28). Superiority margin for the primary end point was set as low as 5.0 percentage points. Since the 95% CI for the difference in effect of the 2 regimens overlaps zero not crossing the superiority margin, the strategy of preventive verapamil use may not be considered superior to the policy of ad hoc administration (difference in conversion rates 1.0%, 95% CI −1.1% to 3.3%).

Figure 3.

Subjective pain. Pain score measured on a semiquantitative scale was equally distributed in the 2 arms (Cochran‐Armitage test, P for trend=0.12). The majority of the patients had no or minimal pain in both groups.

Figure 4.

Analysis of code breaks and efficacy of ad hoc used verapamil. Ad hoc used verapamil was effective in all cases of radial artery spasm, the conversions were due to anatomical variations.

Figure 5.

Treatment effect of verapamil for access site conversion, radial artery spasm, and access site conversion due to radial artery spasm. All 2‐sided 95% CIs for the differences in event rates overlap zero and do not cross the prespecified superiority margin of 5%, suggesting that the policy of prophylactic verapamil application may not be superior to the strategy of ad hoc administration (difference in access site conversion rates: 1.0%, 95% CI −1.1% to 3.3%; difference in rate of radial artery spasm [RAS]: 0.7%, 95% CI −1.5% to 3.1%; difference in occurrence of access site crossover due to RAS: −0.3%, 95% CI −1.9% to 1.0%).