Heart rate and heart failure. Not a simple relationship

Area of Science:

• Cardiology
• Heart Failure Pathophysiology

Background:

• Resting heart rate (HR) is elevated in heart failure (HF) patients.
• Sustained tachycardia can exacerbate or cause HF.
• HR reduction in HF trials correlates with mortality reduction, but the causal role is debated.

Purpose of the Study:

• To review the pathophysiology of tachycardia-induced HF.
• To discuss the force-frequency relationship in HF.
• To evaluate the clinical potential of HR reduction in HF.

Main Methods:

• Literature review of relevant clinical trials and physiological concepts.
• Analysis of data from trials like BEAUTIFUL and SHIFT.
• Discussion of pathophysiological mechanisms linking HR and HF.

Main Results:

• HR reduction magnitude in HF trials is linked to mortality benefits.
• Selective HR reduction trials show mixed results (e.g., SHIFT positive, BEAUTIFUL inconclusive for HF outcomes).
• The mechanistic role of HR in HF pathophysiology remains incompletely understood.

Conclusions:

• Tachycardia's role in HF pathophysiology is complex.
• Clinical benefits of HR reduction in HF are not universally consistent.
• Further research is needed to clarify the precise role and optimal strategies for HR management in HF.