Dante Antonelli

Complete atrioventricular block after sublingual isosorbide dinitrate

A 71-year-old woman, admitted for chest pain, received a 5 mg dose of isosorbide dinitrate sublingually. Within 2 min she became pale and diaphoretic and soon after lost consciousness. A monitor electrocardiographic lead showed sinus bradycardia followed by ventricular asystole. Sinus rhythm was restored by a precordial thump and intravenous administration of atropine. Our patient was receiving lidocaine intravenously because of ventricular premature beats. Its interaction with isosorbide is suspected of having caused the asystole.

Retention of semifloating electrode catheter

A semifloating electrode was prophylactically inserted in an 84-year-old man because of the presence of bifascicular block and the suspicion of acute myocardial infarction. After 6 days it was decided to remove the electrode, but its extraction was not possible. This case demonstrates that retention of semifloating electrode, although a rare complication of temporary right ventricular pacing, is more than a theoretical hazard.