Objective: To describe successful treatment of third-degree atrioventricular (AV) block using temporary noninvasive transthoracic pacing and placement of a permanent transvenous pacemaker in a case of suspected lily-of-the-valley (Convallaria majalis) intoxication in a dog.
Case summary: A 2-year-old neutered male Beagle weighing 17.8 kg was presented to the emergency service for treatment of bradycardia, vomiting, and lethargy. An electrocardiogram revealed third-degree AV block that was nonresponsive to atropine. Ten hours after admission, the dog became obtunded. Treatment initially consisted of temporary noninvasive transthoracic pacing and eventually placement of a permanent transvenous pacemaker. The initial history did not suggest that the dog had access to any known cardiotoxins. However, C. majalis, which contains cardiac glycosides, was identified within the dog's environment and the dog's serum did contain digoxin or an immunologically cross-reactive compound.
New or unique information provided: This is the first reported successful management of C. majalis toxicosis in a dog. Temporary noninvasive transthoracic pacing was used in the management of this case as a safe and effective bridge to permanent pacemaker implantation.