Ivabradine Use and Exercise Capacity Post-Atrial Switch Repair for Transposition of Great Arteries
In brief
Ivabradine lowered exercise heart rate by 15 beats per minute after atrial switch
In a small crossover study, 10 patients with transposition of the great arteries after atrial switch repair completed four weeks each of ivabradine and placebo. Ivabradine lowered peak exercise heart rate and raised oxygen pulse, but the increase in peak oxygen consumption was not conclusive. One patient had symptomatic slow heart rate and one reported visual flashes, leaving benefits and tolerability uncertain.
- Journal
- JACC. Advances (Q1)
- Published
- 23 September 2026
- Study design
- Randomized controlled trial
- Evidence level
- Level 1, High (CEBM 1b)
- Authors
- William M Wilson, Luke Burchill, Sue Finch, Leeanne Grigg, Louis Irving, Hilary Harrington, et al.
- PMID
- 42777583
- DOI
- 10.1016/j.jacadv.2026.103276
Why clinicians should know about it
- Picked for Cardiology and Cardiovascular Medicine (paper of the day, 26 September 2026): ivabradine lowered HR, increased O₂ pulse
Abstract
BACKGROUND: There are few proven therapies for improving exercise capacity in patients with transposition of the great arteries who have undergone an atrial switch repair. OBJECTIVES: The objective of the study was to evaluate the effect of heart rate lowering using ivabradine on exercise capacity and quality of life in this cohort. METHODS: In this single-center, randomized, double-blind, crossover study, patients were randomized to ivabradine or placebo for 4 weeks then crossover treatment for 4 weeks. A cardiopulmonary stress test and quality of life assessment were performed at baseline then at weeks 4 and 8. Estimates of difference were described using a mixed effects model. RESULTS: A total of 19 patients were eligible and 10 patients completed the study. Compared to placebo, ivabradine treatment was associated with lower heart rate at baseline (65 ± 3 beats/min on ivabradine vs 79 ± 5 beats/min on placebo, difference -14.6 [-24, -5]; P = 0.008) and at peak exercise (131 ± 7 beats/min vs 146 ± 7 beats/min, difference -15.3 [-24, -6]; P = 0.003). Peak oxygen consumption was 20.4 ± 1.2 mL/kg/min on ivabradine vs 19.2 ± 1.2 mL/kg/min on placebo (difference +1.2 [-0.09, 2.6]; P = 0.06). Peak oxygen pulse was higher on ivabradine compared to placebo (12.5 ± 1.2 vs 10.7 ± 1.2 mL/beat, difference +1.7 [0.9, 2.6]; P = 0.002). Visual analog score was 73.5 ± 5.6 on ivabradine vs 62.5 ± 5.6 on placebo (mean difference 11.0 [-1.6, 23.6]; P = 0.08). One patient developed symptomatic bradycardia and one patient experienced phosphenes. CONCLUSIONS: Ivabradine use in patients with transposition of the great arteries and atrial switch repair lowered peak heart rate with exercise and was associated with a higher oxygen pulse. (Effect of Ivabradine use on exercise capacity in patients with transposition of the great arteries [TGA] post atrial switch repair; ACTRN12621000196842).
Abstract as published, via PubMed.
For healthcare professionals. The summary is generated by AI from the published abstract, and the evidence level is assigned automatically from the study design on the Oxford CEBM hierarchy. Neither is medical advice. Read the full paper before changing practice.