Pace and Ablate Strategy: Conduction system pacing with AV junction ablation for drug refractory atrial arrhythmia

Pace and Ablate Strategy: Conduction system pacing with AV junction ablation for drug refractory atrial arrhythmia – A novel approach

Dr. P. Vijay Shekar

Department of Cardiology, Kauvery-Heart City, Trichy, India

*Correspondence: Tel. +91 96864 69004; email: vijayshekarpcmc@gmail.com

Case Presentation

A 44-year-old female presented with recurrent episodes of palpitations and breathlessness.

Her past history is significant for rheumatic heart disease of the mitral valve with mechanical valve replacement 8 years ago.

Patient has been suffering from frequent episodes of similar complaints for the past 6 months – requiring hospitalization thrice in the past 3 months.

ECG and Holter during episodes of palpitations showed predominantly atrial flutter with episodes of atrial fibrillation and atrial tachycardia (Fig. 1). ECHO demonstrated a normally functioning mitral prosthesis, a dilated left atrium (48 mm) and left ventricular dysfunction (LVEF: 45%) and moderate pulmonary hypertension.

Patient continued to be symptomatic despite multiple antiarrhythmic drugs. In view of persistent symptoms despite treatment and worsening LV function, options of “pace and ablate strategy” and radiofrequency ablation was considered.

Patient underwent successful AV nodal ablation along with conduction system pacing (Fig. 2). Conduction system pacing – Left bundle branch area pacing (LBBaP)was accomplished using a Select Secure 3830 lead and His315 sheath (Medtronic). Selective LBB capture, stable position of lead within septum (Fig. 3a) and satisfactory lead thresholds were confirmed. Following pacemaker implantation, AV nodal ablation was done through femoral approach using a non-irrigated 3.5 mm tip ablation catheter (Fig. 3b).

Patient had an uneventful recovery. Patient remains symptom free following the procedure.

Discussion

Atrial arrhythmias in a background of rheumatic heart disease and mechanical prosthetic valve remain a challenging subset to treat [1]. Drug refractory atrial tachyarrhythmias can lead to worsening of LV function due to tachycardiomyopathy- leading to further worsening of the clinical status. Though radiofrequency ablation is a treatment option, it is associated with high failure and high recurrence rates in such subset of patients.

AV nodal ablation is an established strategy for drug refractory atrial fibrillation [2]. As most of the hemodynamic effects of atrial arrhythmias are due to high ventricular rates, disrupting AV nodal conduction relieves patient symptoms by dissociating the atrium from the ventricle. Cardiac resynchronization therapy (CRT) with biventricular pacing (Bi V pacing) is recommended following AV nodal ablation in patients with LV dysfunction [3]. However, in our patient, conduction system pacing – left bundle branch area pacing (LBBaP) was used as an alternative to conventional BiV pacing. LBBaP offers advantage of physiologic pacing, thereby improving LV function.

Conclusion

Conduction system pacing with AV nodal ablation – “Pace and ablate” strategy is a novel approach in treatment of drug refractory atrial fibrillation, especially in rheumatic subsets where conventional treatment options may offer little benefit.

References

[1] Iung B, et al. Management of atrial fibrillation in patients with rheumatic mitral stenosis. Heart. 2018;104(13):1062-1068.

Chatterjee NA, et al. Atrioventricular nodal ablation in atrial fibrillation. Circ Arrhythm Electrophysiol. 2012;5:68-76.

Brignole M, et al. APAF-CRT Trial Investigators. AV junction ablation and cardiac resynchronization for patients with permanent atrial fibrillation and narrow QRS: the APAF-CRT mortality trial. Eur Heart J. 2021;42(46):4731-4739.

Dr. P. Vijay Shekar

Department of Cardiology, Kauvery-Heart City, Trichy, India

Pace and Ablate Strategy: Conduction system pacing with AV junction ablation for drug refractory atrial arrhythmia – A novel approach