Implanted defibrillators in trouble: initial device misclassification leads to correct diagnosis-a case series

Area of Science:

• Cardiology
• Electrophysiology
• Medical Diagnostics

Background:

• Supraventricular tachycardia (SVT) misdiagnosed as ventricular tachycardia (VT) can trigger inappropriate implantable cardioverter-defibrillator (ICD) therapy.
• Inappropriate ICD therapy is linked to increased patient morbidity and mortality.
• Accurate arrhythmia diagnosis is crucial for patient safety and effective treatment.

Observation:

• This study details three cases where stored electrograms were analyzed for arrhythmia diagnosis.
• Initial differential diagnoses included VT, focal atrial tachycardia (AT), atrio-ventricular re-entry tachycardia (AVRT), and atrio-ventricular nodal re-entry tachycardia (AVNRT).
• The cases were diagnosed as AVNRT, AVRT, and ectopic AT, respectively.

Findings:

• Detailed analysis of stored electrograms enabled accurate diagnosis of SVTs in all presented cases.
• The diagnoses were subsequently confirmed through electrophysiological studies.
• Stored electrogram analysis proved effective in differentiating various supraventricular tachycardias.

Implications:

• Accurate interpretation of stored electrograms can prevent inappropriate ICD shocks.
• Improved diagnostic strategies can reduce patient morbidity and mortality associated with incorrect arrhythmia management.
• Electrophysiological study confirmation validates the utility of stored electrogram analysis in clinical practice.