Clinical assessment of beta blockade

Academic Article

Abstract

  • This study was undertaken to assess a clinical measurement (leg squats) in order to determine the adequacy of beta‐adrenergic blockade (AdBB) utilizing the symptom‐limited exercise test heart rate of less than 120 beats/min as the standard. Seventy subjects were tested, 35 receiving beta‐adrenergic‐blocking drugs in clinically determined maximal doses, and 35 subjects not receiving these agents. Sensitivity (Se), specificity (Sp), and positive (Pv +) and negative (Pv ‐) predictive values were calculated for post‐leg squat heart rates of ≤ 100, ≤ 110 and < 120 beats/min. Other variables analyzed for AdBB were resting heart rates and post‐leg squat heart rate increase > 50% over baseline. A cost‐benefit analysis was also performed. It was concluded that: (1) Neither the resting heart rate or percent increase in heart rate compared to baseline reliably predicted AdBB. (2) In patients receiving beta‐blocking drugs, a post‐squat heart rate of ≤ 100 beats/min had a Se = .82, Sp = .67, Pv + .70, and Pv ‐ .80, values not high enough to be reliably used in many clinical situations. (3) If the post‐squat heart rate was > 110 beats/min, however, AdBB is probably absent, since no subjects on beta blockers with maximum exercise test heart rate ≤ 120 beats/min had a post‐leg squat heart rate > 110 beats/min. (4) For a reasonable range of cost and test performance estimates, utilization of the leg squat test as described here is favored on the basis of cost‐benefit analysis. Copyright © 1988 Wiley Periodicals, Inc.
  • Published In

    Digital Object Identifier (doi)

    Author List

  • Weston MW; Glasser SP; Stoner DJ; Lyman GH
  • Start Page

  • 311
  • End Page

  • 316
  • Volume

  • 11
  • Issue

  • 5