Intragraft Verapamil: “An Ounce of Prevention is Worth a Pound of Cure”

In the current issue of the Journal, Michaels et al.1 provide convincing evidence that the prophylactic administration of verapamil prior to percutaneous coronary intervention (PCI) of saphenous vein grafts See Michaels et al. on pages 299–302 reduces the incidence of no-reflow and improves myocardial perfusion. From a randomized trial, they provide evidence-based support for a strategy we have employed for almost 3 years. Several caveats to the important observations of Michaels et al. should be noted. First, although the number of patients evaluated is small, the methodology for evaluation is both sophisticated and conclusive. Were the investigators blinded to the study drug (verapamil) and was a placebo control used? The strategy of placebo-controlled blinding would strengthen the observations made. Did these patients receive any routine, critical care pathway-driven anticholinergic (atropine) treatment? Was atropine administered prophylactically prior to verapamil treatment in any of these patients? We have observed atrioventricular (AV) dissociation and transient sinus arrest following intragraft verapamil (200 µg) in patients with pre-treatment first-degree AV block and/or bradycardia. Verapamil has been utilized as a provocative test for underlying sinus node dysfunction. In the context of the very small number of patients enrolled in this study, low frequency occurrence of adverse responses to verapamil could easily be missed. We have employed prophylactic intragraft nitroprusside (100–200 µg, a direct donor of nitric oxide2), in place of verapamil in patients with pre-procedural bradycardia (sinus rate

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