A case is presented that demonstrates a confusing problem of ventricular undersensing in the DDI pacing mode. Electrocardiographic monitoring of the patient after pacemaker implantation revealed intermittent ventricular channel outputs which appeared to be inappropriate. These occurred a period of time after the intrinsic R wave, equal to the programmed AV interval. This problem was caused by ventricular lead undersensing, which resulted when the patient's intrinsic rate was such that the intrinsic ventricular complex occurred during the ventricular blanking period. The problem was corrected by reprogramming the blanking period.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.