Indian Pacing Electrophysiol. J.

ISSN 0972-6292

Home Page Current Issue List of Editors

Indian Pacing Electrophysiol. J. 2004;4(4):221-222           Arrhythmia Quiz 4

Arrhythmia Diagnosis Following An ICD Shock

Download PDF  139 KB 

Roy M. John, MD, PhD

Address for correspondence: Roy M. John, MD, PhD, Section of Cardiology, Lahey Clinic  Medical Center, 41 Mall Road, Burlington, MA 01805. Email:

            A 70 year old male underwent placement of a Medtronic Marquis DR ICD following syncope. He has coronary artery disease and severe LV dysfunction and was inducible for rapid hemodynamically unstable ventricular tachycardia at intracardiac electrophysiological study prior to implantation of the ICD. Three weeks later, he presents with an ICD shock. He had been drinking excessive amounts of alcohol and experienced lightheadedness prior to experiencing the ICD shock. Electrogram of the episode obtained upon device interrogation is shown in Figure 1:

Click Here to Enlarge
Figure 1: From top to bottom, the traces represent atrial electrograms, ventricular electrograms, atrial and ventricular marker channels with inter-beat intervals.

Which of the following is a true statement regarding this arrhythmia?
1. A ventricular arrhythmia is appropriately converted by the ICD shock
2. Activation of SVT discrimination algorithms would have prevented an ICD shock
3. A ventricular arrhythmia leads to the development of atrial fibrillation
4. There is 1:1 atrio-ventricular conduction during an atrial tachycardia leading to an ICD shock
5. An AV node dependent supra-ventricular tachycardia is appropriately terminated by the ICD shock

Arrhythmia Quiz 4 - Answer

Home Page Current Issue List of Editors