What resting heart rate should one aim for when treating patients with heart failure with a beta-blocker? Experiences from the Metoprolol Controlled Release/Extended Release Randomized Intervention Trial in Chronic Heart Failure (MERIT-HF)

• OBJECTIVES: The goal of this study was to explore the question: what resting heart rate (HR) should one aim for when treating patients with heart failure with a beta-blocker? BACKGROUND: The interaction of pretreatment and achieved resting HR with the risk-reducing effect of beta-blocker treatment needs further evaluation. METHODS: Cardiovascular risk and risk reduction were analyzed in five subgroups defined by quintiles (Q) of pretreatment resting HR in the Metoprolol Controlled Release/Extended Release Randomized Intervention Trial in Chronic Heart Failure (MERIT-HF). RESULTS: Mean baseline HR in the 5 Qs were 71, 76, 81, 87, and 98 beats/min; achieved HR 63, 66, 68, 72, and 75 beats/min; and net change -8, -10, -11, -13, and -14 beats/min, respectively. Baseline HR was related to a number of baseline characteristics. Cardiovascular risk was no different in Q1 to Q4 (placebo groups) but increased in Q5 (HR above 90 beats/min). No relationship was observed between the risk-reducing effect of metoprolol controlled release/extended release (CR/XL) and baseline HR in the five Qs of baseline HR, or achieved HR, or change in HR during follow-up, respectively. CONCLUSIONS: Metoprolol CR/XL significantly reduced mortality and hospitalizations independent of resting baseline HR, achieved HR, and change in HR. Achieved HR and change in HR during follow-up were closely related to baseline HR; therefore, it was not possible to answer the question posed. Instead, one has to apply a very simple rule: aim for the target beta-blocker dose used in clinical trials, and strive for the highest tolerated dose in all patients with heart failure, regardless of baseline and achieved HR.

Keyword

Adrenergic beta-Antagonists/*therapeutic use

Adult

Aged

Aged

80 and over

Chronic Disease

Delayed-Action Preparations

Female

Follow-Up Studies

Heart Failure

Congestive/*drug therapy/mortality/*physiopathology

Heart Rate/*physiology

Hospitalization

Humans

Male

Metoprolol/*analogs & derivatives/*therapeutic use

Middle Aged

Prospective Studies

Rest/*physiology

Risk Assessment

Treatment Outcome

Publication and Content Type

ref (subject category)

art (subject category)