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Relation of beta-blocker-induced heart rate lowering and cardioprotection in hypertension

Sripal Bangalore1, Sabrina Sawhney, Franz H Messerli

  • 1Department of Medicine, Division of Cardiology, St Luke's Roosevelt Hospital, Columbia University College of Physicians and Surgeons, New York, New York 10019, USA.

Journal of the American College of Cardiology
|November 20, 2008
PubMed

Insights

Beta-blockers lower heart rate in hypertension patients, but this reduction paradoxically increases cardiovascular risks. This contrasts with benefits seen in heart failure and post-myocardial infarction patients.

Area of Science:

  • Cardiology
  • Pharmacology
  • Hypertension Research

Background:

  • Elevated resting heart rate is a known cardiovascular risk factor in the general population and in patients with conditions like hypertension.
  • Pharmacological heart rate reduction is generally beneficial for individuals with existing heart disease.
  • The specific impact of beta-blockers on heart rate and cardiovascular event risk in hypertensive patients remains unclear.

Purpose of the Study:

  • To investigate the effect of heart rate reduction achieved with beta-blockers on the risk of cardiovascular events in patients diagnosed with hypertension.

Main Methods:

  • A comprehensive literature search was conducted across MEDLINE, EMBASE, and CENTRAL databases for studies published from 1966 to May 2008.
  • Included were randomized controlled trials (RCTs) using beta-blockers as a primary hypertension treatment, with a minimum one-year follow-up and available heart rate data.
  • Data extracted included baseline characteristics, blood pressure response, heart rate changes, and cardiovascular outcomes.

Main Results:

  • Analysis of 9 RCTs involving 34,096 patients on beta-blockers, 30,139 on other antihypertensives, and 3,987 on placebo revealed a concerning trend.
  • A lower heart rate at study conclusion in the beta-blocker group was paradoxically associated with increased risks of all-cause mortality, cardiovascular mortality, myocardial infarction, and heart failure.
  • This association persisted when comparing heart rate differences with relative risk reduction for cardiovascular events.

Conclusions:

  • Unlike patients with myocardial infarction or heart failure, hypertensive patients experiencing beta-blocker-induced heart rate reduction showed an elevated risk of cardiovascular events and mortality.
  • These findings challenge the universal application of heart rate reduction as a sole therapeutic goal in hypertension management.
Abstract

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