Haqeel A Jamil1, John Gierula2, Maria F Paton1, Roo Byrom1, Judith E Lowry1, Richard M Cubbon1, David A Cairns2, Mark T Kearney1, Klaus K Witte3. 1. Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, United Kingdom. 2. Clinical Trials Research Unit, Leeds Institute of Clinical Trials Research, Leeds, United Kingdom. 3. Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, United Kingdom. Electronic address: k.k.witte@leeds.ac.uk.
Abstract
BACKGROUND: Limited heart rate (HR) rise (HRR) during exercise, known as chronotropic incompetence (CI), is commonly observed in chronic heart failure (CHF). HRR is closely related to workload, the limitation of which is characteristic of CHF. Whether CI is a causal factor for exercise intolerance, or simply an associated feature remains unknown. OBJECTIVES: This study sought to clarify the role of the HR on exercise capacity in CHF. METHODS: This series of investigations consisted of a retrospective cohort study and 2 interventional randomized crossover studies to assess: 1) the relationship between HRR and exercise capacity in CHF; and 2) the effect of increasing and lowering HR on exercise capacity in CHF as assessed by symptom-limited treadmill exercise testing and measurement of peak oxygen consumption in patients with CHF due to left ventricular systolic dysfunction. RESULTS: The 3 key findings were: 1) the association of exercise capacity and HRR is much weaker in severe CHF compared to normal left ventricular function; 2) increasing HRR using rate-adaptive pacing (versus fixed-rate pacing) in unselected patients with CHF does not improve peak exercise capacity; and 3) acutely lowering baseline and peak HR by adjusting pacemaker variables in conjunction with a single dose of ivabradine does not adversely affect exercise capacity in unselected CHF patients. CONCLUSIONS: The data refute the contention that CI contributes to impaired exercise capacity in CHF. This finding has widespread implications for pacemaker programming and the use of heart-rate lowering agents. (The Influence of Heart Rate Limitation on Exercise Tolerance in Pacemaker Patients [TREPPE]; NCT02247245).
BACKGROUND: Limited heart rate (HR) rise (HRR) during exercise, known as chronotropic incompetence (CI), is commonly observed in chronic heart failure (CHF). HRR is closely related to workload, the limitation of which is characteristic of CHF. Whether CI is a causal factor for exercise intolerance, or simply an associated feature remains unknown. OBJECTIVES: This study sought to clarify the role of the HR on exercise capacity in CHF. METHODS: This series of investigations consisted of a retrospective cohort study and 2 interventional randomized crossover studies to assess: 1) the relationship between HRR and exercise capacity in CHF; and 2) the effect of increasing and lowering HR on exercise capacity in CHF as assessed by symptom-limited treadmill exercise testing and measurement of peak oxygen consumption in patients with CHF due to left ventricular systolic dysfunction. RESULTS: The 3 key findings were: 1) the association of exercise capacity and HRR is much weaker in severe CHF compared to normal left ventricular function; 2) increasing HRR using rate-adaptive pacing (versus fixed-rate pacing) in unselected patients with CHF does not improve peak exercise capacity; and 3) acutely lowering baseline and peak HR by adjusting pacemaker variables in conjunction with a single dose of ivabradine does not adversely affect exercise capacity in unselected CHF patients. CONCLUSIONS: The data refute the contention that CI contributes to impaired exercise capacity in CHF. This finding has widespread implications for pacemaker programming and the use of heart-rate lowering agents. (The Influence of Heart Rate Limitation on Exercise Tolerance in Pacemaker Patients [TREPPE]; NCT02247245).
Authors: Joachim Proff; Béla Merkely; Roland Papp; Corinna Lenz; Peter Nordbeck; Christian Butter; Juergen Meyerhoefer; Michael Doering; Dean J MacCarter; Katharina Ingel; Thomas Thouet; Ulf Landmesser; Mattias J Roser Journal: Europace Date: 2021-11-08 Impact factor: 5.214