The pathophysiology of heart failure with preserved ejection fraction (HFpEF) is complex and multifactorial. Chronotropic incompetence (ChI) has emerged as a crucial pathophysiological mechanism. Beta-blockers, drugs with negative chronotropic effects, are commonly used in HFpEF, although current evidence does not support its routine use in these patients.

We postulate beta-blockers may have deleterious effects in HFpEF and ChI. This work aims to evaluate the short-term effect of beta-blockers withdrawal on functional capacity assessed by the maximal oxygen uptake (peakVO2) in patients with HFpEF and ChI.

This is a prospective, crossover, randomized (1:1) and multicenter study. After randomization, the clinical and cardiac rhythm will be continuously registered for 30 days. PeakVO2 is assessed by cardiopulmonary exercise testing (CPET) at 15 and 30 days in both groups. Secondary endpoints include quality of life, cognitive, and safety assessment. Patients with stable HFpEF, functional class New York Heart Association (NYHA) II-III, chronic treatment with beta-blockers, and ChI will be enrolled. A sample size estimation [alfa: 0.05, power: 90%, a 20% loss rate, and delta change of mean peakVO2: +1.2 mL/kg/min (SD ± 2.0)] of 52 patients is necessary to test our hypothesis.

Patients started enrolling in October 2018. As January 14th, 2020, 28 patients have been enrolled. It is projected to enroll the last patient at the end of July 2020.

Optimizing therapy that improves functional capacity remains an unmeet priority in HFpEF. Deprescribing beta-blockers in patients with HFpEF and ChI seems a plausible intervention to improve functional capacity. This trial is an attempt towards precision medicine in this complex syndrome.

ClinicalTrials.gov: NCT03871803.