Prospective randomized trial of conduction system pacing vs right ventricular pacing for patients with atrioventricular block; Prague CSP trial.

BACKGROUND

Conduction system pacing (CSP) replaces right ventricular pacing (RVP) in bradycardia patients.

OBJECTIVE

To compare CSP vs RVP in patients with pacemaker indication due to atrioventricular conduction disease.

METHODS

This study randomized patients to CSP or RVP in 1:1 ratio and followed them for 12 months. CSP received either His bundle pacing or left bundle branch area pacing; The primary end point was a change in the left ventricular ejection fraction (LVEF). The combined composite clinical end point consisted of cardiovascular death, cardiac resynchronization therapy upgrade, or hospitalization for heart failure.

RESULTS

Of 249 patients, 125 were randomized to RVP and 124 to CSP; there were no differences between clinical parameters. In CSP, 10 patients received His bundle pacing, 96 left bundle branch area pacing, 15 deep septal pacing, and 3 RVP. Procedural and fluoroscopy times were longer in CSP vs RVP (63 vs 40 and 7 vs 3 minutes; P < .001). In the intention-to-treat analysis, the LVEF decline in CSP was smaller than RVP (-2% vs -4%, P = .03), and a LVEF decrease ≥ 10% occurred more often in RVP 19 (16%) than CSP 6 (5%), P = .01. There was no difference in the composite clinical outcome between RVP and CSP (9 vs 4, P = .15). There was also no difference in procedural complications (9 in RVP vs 2 in CSP, P = .09).

CONCLUSION

In patients with severe conduction disease, CSP led to a smaller LVEF decline than RVP after 1 year of pacing. Both pacing methods had similar rates of clinical end points and procedural complications.