Frequent inappropriate implantable cardioverter defibrillator therapy was determined to be dual atrioventricular nodal non-reentrant tachycardia: A case report.

RATIONALE

Dual atrioventricular node non-reentrant tachycardia (DAVNNRT) is a rare arrhythmia. We present a case of inappropriate implantable cardioverter defibrillator (ICD) therapy caused by DAVNNRT. DAVNNRT is easily misdiagnosed as atrial fibrillation and is often identified as ventricular tachycardia (VT) by the supraventricular tachycardia-ventricular tachycardia (SVT-VT) discriminator of the ICD.

PATIENT CONCERNS

A 73-year-old man with ischemic heart disease (IHD) presented with palpitations accompanied by dyspnea and syncope. Frequent multifocal premature ventricular beats and non-sustained ventricular tachycardia were observed on ambulatory electrocardiography. The left ventricular ejection fraction decreased to 32%.

DIAGNOSIS

He was diagnosed with IHD, heart failure with reduced ejection fraction (HFrEF), and VT.

INTERVENTIONS

: Initially, the patient received a single-chamber ICD implantation for secondary prevention of sudden death. He then suffered from inappropriate anti-tachycardia pacing (ATP)/shock therapy many times after the procedure. DAVNNRT was confirmed in an electrophysiology study (EPS), and radiofrequency ablation of the slow pathway successfully terminated this tachycardia.

OUTCOMES

No episode of inappropriate ICD therapy or tachycardia occurred during the follow-up.

LESSONS

In conclusion, it is essential to have a full understanding of DAVNNRT and eliminate slow pathways for patients with DAVNNRT and be prepared to implant an ICD.