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Heterologous Atrial-Only Leadless Rescue of Pacemaker Syndrome With Preserved Atrioventricular Conduction
Badal Sojitra1, Shiv Gakhar1, Baylen Shoemaker1
1Division of Cardiology, Department of Internal Medicine, HCA Healthcare/USF Morsani College of Medicine GME/HCA Florida Largo Hospital, Largo, Florida, USA.
Background:
The Medtronic Micra AV leadless pacemaker (LP) can preserve atrioventricular synchrony via accelerometer-based mechanical sensing; however, tracking limitations may result in pacemaker syndrome.
Case Summary:
A 61-year-old woman underwent Micra AV LP implantation for symptomatic postoperative junctional bradycardia after redo aortic root and bioprosthetic aortic valve replacement for prosthetic valve endocarditis, which was complicated by postoperative stroke and recurrent infections. She developed persistent exertional dyspnea despite recovery of left ventricular function and normal prosthetic valve function. Interrogation showed 100% ventricular pacing; electrocardiography showed retrograde P waves; and exercise testing identified preserved antegrade conduction. An Abbott Aveir atrial LP was implanted to restore atrioventricular synchrony, whereas the prior Micra LP was retained as low-rate ventricular backup.
Discussion:
Atrial-only leadless rescue reduced ventricular pacing to 0.1% and resolved symptoms without transvenous upgrade or prior device extraction.
Take-Home Message:
Provocative testing can identify select patients in whom heterologous atrial-only leadless rescue may restore synchrony without extraction.
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