P1487
Cardiac resynchronization through His bundle pacing in patients with heart failure

Permanent His bundle pacing (p-HBP) can correct intraventricular conduction disorders and could be a physiological alternative for traditional cardiac resynchronization therapy (CRT) via the coronary sinus: our aim was to describe our results in patients with heart failure and ventricular dysfunction who were resynchronized by p-HBP.

Prospective descriptive study of patients with CRT indication and who were resynchronized by p-HBP, using the specific tools. The correction of bundle branch block (BBB) by His bundle pacing (HBP) has been previously checked. We analyzed: the global success of the implant, the His thresholds, and the improvement in left ventricular ejection fraction (LVEF) at one month of follow-up.

We included 54 patients (median age 66 (56-72)) with an indication for CRT: 89% (n = 48) with heart failure (HF), left bundle block branch (LBBB) and LVEF <35%; 3% (n = 2) with HF, right bundle block branch (RBBB) and LVEF <35%; 2% (n = 1) with permanent pacemaker, ventricular dysfunction and ventricular pacing >40%; and 6 % (n = 3) with complete AV block, LBBB and ventricular dysfunction. With HBP we corrected the BBB in 83% of patients (n = 45), and we achieved cardiac resynchronization through p-HBP in 93% of this patients (n = 42), with a global success (including those in whom HBP did not correct the BBB) of 78% (n = 42).

The basal QRS was 160 ms (151-162) and the paced QRS was 132 ms (125-145). The median of His acute threshold was 1.6 volts (0.9-1.9), stable at one month of follow-up, excluding one patient whose His threshold progressively increased to 5.5 volts. There was no dislocation of leads in the follow-up. LVEF improved in all patients: basal 30% (27-35) and at one month follow-up 52% (48-64). Median fluoroscopy times of device implantation including the time taken for temporary HBP were 8.1 minutes (range 6.1-9.9). There were no relevant complications during the implant or follow-up; all patients showed clinical subjective improvement.

CRT by p-HBP is feasible and safe in a high percentage of patients, with reasonable times of fluoroscopy, acceptable capture thresholds, and an early improvement in LVEF in patients with HF and an indication for CRT.