First in the world case series of one lead only CRT-D with LBBAP. Feasibility and effectiveness

Patients with HFrEF and conduction major disorders (i.e. AV block, LBBB or intraventricular conduction delay) have Class I indication to Cardiac Resynchronization Therapy. Recently, CSP is emerging as an alternative to traditional biventricular pacing in order to treat conduction disorders, but few data are available about LBBAP performed with an high voltage lead

Aim of our experience is to demonstrate feasibility and effectiveness in pacing and defibrillation of a CRT-D system with just one HV lead with atrial sensor, implanted on LBBA to perform CSP. We report the first four cases worldwide.

We implanted 4 patients (3 male, 66±11 yo) with HFrEF and sinus rhythm with major electrical conduction disorders (2 cases of >300 ms 1st degree AV block, 1 case of 3rd degree paroxysmal AV block, and 1 case of interventricular conduction delay) with a single coil, active fixation, high voltage lead with atrial sensor. The lead was implanted on LBBA using a transeptal puncture sheath 8.5F inner diameter with a 120 degree distal tip, manually shaped to obtain a three dimensional curve to support septum penetration. Delivery sheath was deprived of the valve, shortened by 13 cm and finally cut to support the cutting maneuver of the slider. LBBAP was checked in unipolar stimulation with standard parameters (stimulus to V6Rwave peak and V6Rwave peak to V1R’wave peak). After implantation defibrillation test was performed to assess efficacy of therapy. One day, one week, one month, three months and six months follow-up was performed and patients have been enrolled in home monitoring outpatient.

All implantation obtain successful CSP (mean QRS duration 108 ms). Mean fluoroscopy time, excluding the very first case, was 10 ± 3 minutes and mean total procedure (skin to skin) time was 43±6 minutes, significantly lower than traditional CRT-D mean implantation time recorded in our lab. Electrical parameters at implantation were: mean R wave amplitude 8.2±2.1mV; mean shock impedence 68±12 ohm, mean pacing impedance 540±160 ohm and mean capture threshold was 1.1±0.8V@0.4ms. Defibrillation was effective in all cases at 22J at first attempt. One patient required slight advancing of the lead because of atrial undersensing. During follow-up, no oversensing issue was reported and electrical parameters remained stable. One patient underwent LVOT PVC ablation without consequences for ICD functioning.

One lead CRT performed with a LBBA-Dx system is feasible, effective and easier procedure in comparison to traditional CRT-D. We lack a dedicated delivery sheath to perform this kind of implantation. Further follow-up is needed to assess long term performances this lead implanted on LBBA.

Delivery Sheath Shaping