DOI: https://doi.org/10.36347/sjmcr.2025.v13i10.007

Pages: 2209-2213

Implantable cardioverter-defibrillators (ICD) can be placed to reduce the risk of sudden cardiac death. Dual chamber ICDs have the additional benefit of identifying atrial arrhythmias. However, depending on the arrhythmia as well as the programmed settings for detection, the device may not detect rhythm abnormalities. Relying on a device check report alone to rule out arrhythmias may result in a missed diagnosis. In our case, an 81-year-old male who had a dual chamber ICD presented to the hospital due to worsening congestive heart failure with shortness of breath, weight gain, and lower extremity edema. His electrocardiogram readings were concerning for sinus tachycardia versus atypical atrial flutter versus atrial tachycardia. His ICD interrogation did not record the sustained atrial tachycardia as an abnormal rhythm since the rate was below the tachycardia detection threshold. His evaluation by an electrophysiologist determined that he had focal atrial tachycardia. The electrophysiologist pace-terminated the atrial tachycardia through the ICD. He presented 2.5 months later due to recurrence of atrial tachycardia and underwent successful ablation.