Related Experiment Video
Updated: Nov 25, 2025

Quantitative Autonomic Testing
Published on: July 19, 2011
Shortness of breath and palpitations in an elderly man: Bad device behavior or malfunction?
Gregory P Siroky1, Shawn Lee1, Ranjit Suri1
1Mount Sinai Morningside Icahn School of Medicine at Mount Sinai New York NY USA.
Abstract:
70-year-old male with sinus node dysfunction (SND) and paroxysmal atrial fibrillation presents with shortness of breath and palpitations. Presenting EKG shows AF with rapid ventricular rates requiring direct current cardioversion (DCCV). Post-DCCV EKG shows sinus rhythm with competing ventricular pacing. Device interrogation demonstrates the patient's generator at the elective replacement indicator (ERI) and has been forced to VVI 65 bpm causing dyssynchronous ventricular pacing and inducing AF. This case highlights the importance of close device follow up with timely PPM generator change prior to ERI, especially in patients with Medtronic Adapta devices, to avoid unnecessary dyssynchronous ventricular pacing. In addition, device manufacturers should focus on maintaining AV synchrony in pacemakers when they reach ERI.
Related Concept Videos
Coronary Artery Disease III: Clinical Manifestations
Dysrhythmias VII: Nursing Management of Dysrhythmias
Decreased pulse rate
There are specific risk factors that can elevate the likelihood of developing bradycardia. Advanced age is a significant factor, with...
Dysrhythmias V: Evaluating Dysrhythmias
Heart Failure III: Clinical Manifestations
Angina III: Clinical Manifestations and Assessment

