Effects of haemodynamically atrio-ventricular optimized His-pacing on heart failure symptoms and exercise capacity: The His Optimized Pacing Evaluated for Heart Failure (HOPE-HF) randomised, double-blind, cross-over trial

Abstract

Aims: Excessive prolongation of PR interval impairs coupling of AV contraction, which reduces left ventricular pre-load and stroke volume, and worsens symptoms. His-bundle pacing allows AV-delay shortening while maintaining normal ventricular activation. HOPE-HF evaluated whether AV-optimized His pacing is preferable to no-pacing, in double-blind cross-over fashion, in patients with heart failure, left ventricular ejection fraction (LVEF) ≤40%, PR interval ≥200ms and either QRS ≤140ms or right BBB. Methods and Results: Patients had atrial and His-bundle leads implanted (and an ICD lead if clinically indicated) and were randomized, to 6-months of pacing and 6-months of no-pacing utilizing a cross-over design. The primary outcome was peak oxygen uptake during symptom-limited exercise. Quality of life, LVEF and patients' holistic symptomatic preference between arms were secondary outcomes. 167 patients were randomized: 90% men, 69±10 years, QRS duration 124±26ms, PR interval 249±59ms, LVEF 33±9%. Neither peak VO 2 (+0.25 ml/min/kg, 95% CI -0.23 to +0.73, p=0.3) nor LVEF (+0.5%, 95% CI -0.7 to 1.6, p=0.4) changed with pacing but Minnesota Living with Heart Failure quality of life improved significantly (-3.7, 95% CI -7.1 to -0.3, p=0.03). 76% of patients preferred His-bundle pacing-on and 24% pacing-off (p<0.0001). Conclusion: His-bundle pacing did not increase peak oxygen uptake but, under double-blind conditions, significantly improved quality of life and was symptomatically preferred by the clear majority of patients. Ventricular pacing delivered via the His bundle did not adversely impact ventricular function during the 6 months