Background: Several clinical data demonstrate that atrio ventricular junction (AVJ) ablation, followed by cardiac pacing, in atrial fibrillation (AF) with uncontrollable heart rate is beneficial. There are still limited data about conduction system pacing (CSP) in that setting.
Aims. To analyse if this “ablate and pace” strategy is feasible with good electrical results (ECG and parameters) and clinical outcomes (heart failure (HF) admission, ejection fraction (EF) and NYHA class). To analyse also differences between his bundle pacing (HBP) and left bundle branch area pacing (LBBAP) in this setting.
Methods. This is an observational retrospective single center study involving 30 patients of which 11 had a HBP and 19 a LBBAP from March 2019 to June 2023 (medium follow up 33 ± 18 month). The implant procedure was performed with both stylet driven or lumenless lead. After 2 ± 2 weeks was performed the AVJ ablation. The electrical parameters were measured at the implant and every 6 – 12 months. The patients had an echocardiographic and clinical evaluation every 6 – 12 months. There was nobody with a NYHA class IV.
Results. The procedure was performed without complication in all patients. There were a rising in the EF (49,9 ± 14,6 vs 54,2 ± 10,4% p = 0.004). There weren’t HF admission and only 2 patients died (not for cardio-vascular causes) during follow up. There were also a decrease in NYHA class in every patient (at least one NYHA class less). 17 (57%) patients had normal ventricular conduction, only 4 (13%) had LBBB, 4 (13%) RBBB. There were not statistical difference between the QRS duration pre and after implant (129 ± 35 vs 125 ± 24 ms p = 0,06). The threshold measured at the implant were stable both in the HBP (0,75 ± 0,34 vs 1,3 ± 0,8 V @ 0,4 ms p = 0,14) and in the LBBAP (0,93 ± 0,3 vs 0,89 ± 0,3 V @ 0,4 ms p = 0,49). The LBBAP presented higher values of sensing compared with HBP (17,5 ± 7,4 vs 6,3 ± 3,3 mV p = 0,04) and less procedural (63 ± 32 vs 95 ± 41 min, p = 0,02) and fluoroscopic time (2,6 ± 2,4 vs 7,5 ± 4,1 min, p = 0,04) compared with HBP.
Conclusion. The CSP is feasible and safe in the setting of “ablate and pace” and results in a clear increasing in EF and clinical status of patients with good and stable ECG features and electrical parameters during follow up; the CSP indeed represent a valuable alternative to BVP in this setting. LBBAP performed better than HBP in terms of procedural and fluoroscopic time and of higher sensing values.