title: Effect of an L- and T-type calcium channel blocker on 24-hour systolic blood pressure and heart rate in hypertensive patients.
abstract: OBJECTIVE
  The aim of this study was to evaluate the effects of an L- and T-type calcium channel blocker (CCB) on 24-hour systolic blood pressure (24-hour SBP) and heart rate (24-hour HR) profiles in essential hypertensive patients.
  
  
  METHODS
  Thirty-seven consecutive patients were enrolled in this study. The 24-hour SBP and HR were recorded before and after treatment with efonidipine (L- and T-type CCB, 40 mg), after waking. Changes in 24-hour SBP and HR and the diurnal to nocturnal SBP ratio were measured. The best-fit curves of changes in SBP and HR were depicted using a periodic function.
  
  
  RESULTS
  The mean 24-hour SBP and HR decreased significantly after treatment. The diurnal to nocturnal SBP ratio in dipper-type hypertension cases decreased from 16.7±6.1% to 8.3±9.8% (p<0.05), whereas in non-dipper hypertension cases, it increased from 2.3±2.9% to 7.7±5.1% (p<0.01). The antihypertensive effect was minimal at 5.0 hours after drug administration and it slowly recovered at a constant rate (2.1 mm Hg/h) over 12 hours in dipper cases. The median 24-hour changes in HR in the dipper and non-dipper cases were -2.3/min and -5.4/min, respectively. A continuous reduction in the change in HR was seen from 3.5 to 23 hours after drug administration.
  
  
  CONCLUSIONS
  The antihypertensive action of efonidipine was characterized by a slow recovery of the SBP decrease at a constant rate (2.1 mm Hg/h) and a non-administration time dependent reduction in 24-hour HR.
authors.affiliation: Division of Cardiology, Showa University Fujigaoka Hospital, Yokohama, Japan.
authors.forename: Masae
authors.initials: M
authors.lastname: Komukai
authors.forename: Takeshi
authors.initials: T
authors.lastname: Tsutsumi
authors.forename: Mio
authors.initials: M
authors.lastname: Ebado
authors.forename: Youichi
authors.initials: Y
authors.lastname: Takeyama