Pacemaker-mediated polymorphic ventricular tachycardia

Area of Science:

• Cardiology
• Electrophysiology
• Medical Device Technology

Background:

• Polymorphic ventricular tachycardia (PMVT) is a serious arrhythmia often requiring intervention.
• Permanent pacemaker implantation is a strategy for managing refractory bradycardia-dependent arrhythmias.
• Pacemaker-mediated tachycardia (PMT) can be triggered by device programming.

Observation:

• A patient with refractory bradycardia-dependent PMVT received a permanent pacemaker.
• Despite pacemaker implantation, the patient experienced recurrent PMVT.
• Device interrogation revealed a factory-programmed feature (+ PVARP on PVC) as the cause.

Findings:

• The '+ PVARP on PVC' feature, intended to prevent PMT, induced cycle length variability.
• This variability in cardiac cycle length precipitated recurrent PMVT episodes.
• Deactivating the '+ PVARP on PVC' feature successfully resolved the arrhythmia.

Implications:

• Standard pacemaker programming may require individual adjustment for certain arrhythmias.
• Understanding device-feature interactions is crucial for preventing iatrogenic arrhythmias.
• This case highlights the importance of thorough device interrogation and reprogramming in managing complex cardiac conditions.