Pseudo‐Cross‐Stimulation due to First Degree AV Block

Abstract

During routine interrogation of a dual chamber pacemaker, atrial pacing stimulus outputs were found to coincide with surface electrogram QRS complexes raising concern for cross-stimulation. Scrutiny of the native rhythm, however, confirmed this to be "pseudo-cross-stimulation" where marked first degree AV block resulted in alignment of atrial stimulus outputs with preceding QRS complexes. Although cross-stimulation is rare, familiarity with cross-stimulation and pseudo-cross-stimulation is important because its recognition will avoid erroneous diagnoses of lead dislodgment or device malfunction.

Cross‐Stimulation: A Rare Complication of Chronic Epicardial Leads

“…Complications such as abnormal sensing, crosstalk inhibition, high lead thresholds, lead fractures, and lead dislodgment are well known and well described 1 . Cross‐stimulation and pseudo‐cross‐stimulation 2 are rare phenomena but are important to recognize and distinguish from more common complications. Cross‐stimulation is defined as the capture of an unexpected chamber with pacing of a different chamber.…”