PARIS – The threat of radial artery spasm is the chief impediment to broader use of transradial access cardiac catheterization and percutaneous coronary intervention, but Dr. Julien Adjedj has a series of tips and tricks to defeat it.
At Cochin University Hospital in Paris, where he is chief of the interventional cardiology clinic, 95% of all PCIs are done transradially.
“With the tips and tricks we use, we have a transradial approach failure rate of only 1.5% at our center,” Dr. Adjedj said at the annual congress of the European Association of Percutaneous Cardiovascular Interventions.
He and his colleagues have conducted a series of prospective, randomized studies of various prophylactic vasodilator regimens in 1,950 patients undergoing transradial PCI.
The winning strategy? Place 2.5-5.0 mg of the calcium channel blocker verapamil in the arterial sheath as first-line preventive therapy.
In a multivariate analysis adjusted for potential confounders – for example, the investigators found that the incidence of radial artery spasm (RAS) is higher in women and younger patients – the use of prophylactic verapamil placed in the arterial sheath reduced the likelihood of RAS by 75% and 72%, respectively, compared with placebo.
Intra-arterial diltiazem at 5 mg, isosorbide dinitrate at 1 mg, and molsidomine at 1 mg were also more effective than placebo. However, diltiazem and isosorbide dinitrate were associated with an unacceptable increased risk of severe hypotension compared to placebo, and molsidomine is not widely available outside France.
In contrast, verapamil was not linked to severe hypotension.
Overall, RAS occurred in 22.2 % of patients on placebo, 7.1% of those on verapamil at 2.5 mg, 7.9% with verapamil at 5 mg, 6.5% with isosorbide dinitrate at 1 mg, 9.1% of those on diltiazem at 5 mg, 13.3% with molsidomine at 1 mg, and 4.8% with verapamil 2.5 mg plus molsidomine 1 mg.
When it proves difficult to advance the catheter during a transradial PCI despite prophylactic verapamil, the first thing to do is check whether the problem really is RAS or is instead a matter of having entered a remnant artery. This is accomplished by supplementing the verapamil with 1 mg of intra-arterial isosorbide dinitrate; if the catheter still won’t pass, seriously consider the possibility of a remnant artery.
Among Dr. Adjedj’s tips on how to successfully pass the catheter through a drug-refractory RAS: Use a hydrophilic 0.035-inch guide wire, switch from a 6 Fr to a smaller 5 or 4 Fr catheter, or use a long multipurpose 5 Fr catheter inside the 6 Fr guiding catheter.
“It’s like nested Russian dolls. It can pass through the spasm without any pain,” said Dr. Adjedj.
He reported having no financial conflicts regarding his presentation.