Background: 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.
Hypothesis: We postulate beta-blockers may have deleterious effects in HFpEF andChI. 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.Methods: 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 Abbreviations: ChI, chronotropic incompetence; CPET, cardiopulmonary exercise testing; HF, heart failure; HFpEF, heart failure with preserved ejection fraction; HFrEF, heart failure with reduced ejection fraction; NYHA, New York Heart Association; PeakVO2, peak exercise oxygen uptake; QoL, quality of life.Patricia Palau and Julia Seller contributed equally to this study.