Objective and importance: Endless loop tachycardia or pacemaker-mediated tachycardia, and atrioventricular desynchronization arrhythmia or repetitive non-reentrant ventriculoatrial synchrony (RNRVAS) are two forms of reverse impulse conduction - ventriculoatrial (VA) synchrony. Although VA synchrony can theoretically cause aggravation of heart failure, clinical cases describing severe consequential heart failure are lacking.
Clinical presentation and intervention: We describe a case of a 60-year-old patient who underwent primary percutaneous coronary intervention and mitral valve surgery. Implantation of a two-chamber pacemaker was also performed during the same hospitalization due to development of third-degree atrioventricular block. Ten months later, he presented with a severe form of heart failure with a significant reduction of left ventricular ejection fraction (LVEF). The atrial lead was displaced and VA synchrony was registered (RNRVAS-like condition). The pacemaker was reprogrammed and VA synchrony induced heart failure was successfully resolved. Echocardiographic follow-up showed improvement in LVEF.
Conclusion: Ventriculoatrial conduction can be present even when the patient has a complete atrioventricular block. Atrial lead displacement and consequently loss of atrial capture with preserved sensing can be a predisposing factor for initiation of ventriculoatrial synchrony. Permanent ventriculoatrial synchrony may provoke aggravation of heart failure.
Keywords: ECG; Heart failure; complication; lead displacement; pacemaker.