title: Comparison of endothelial function improvement estimated with reactive hyperemia index between ramipril and telmisartan in hypertensive patients.
abstract: BACKGROUND
  Endothelium has a function to regulate vascular tone by releasing mediators either vasodilating or vasoconstricting blood vessels. Endothelial dysfunction can be measured conveniently by Reactive Hyperemia Index (RHI) with a peripheral arterial tonometry. Angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin II (AT II) receptor blockers (ARBs) are considered to have beneficial effects on endothelium through inhibition of AT II. This study was performed to compare the effect of ACEIs or ARBs on endothelial function estimated by RHI in hypertensive patients.
  
  
  METHODS
  Twenty consecutive patients with hypertension (57.9 ± 11.3 years, 60% men) were assigned to receive treatment with ramipril or telmisartan for eight weeks (n =10 per group). Blood pressure (BP) and RHI were measured at baseline and after eight weeks treatment.
  
  
  RESULTS
  The two groups were similar in terms of demographic and laboratory characteristics. But baseline systolic BP and pulse pressure (PP) were higher in telmisartan group than ramipril group (systolic BP, 159 ± 6.83 vs 150 ± 7.49,p =0.028; PP, 75.0 ± 14.0 vs 60.3 ± 12.4,p =0.034). In both groups, systolic and diastolic BP decreased significantly after eight weeks treatment (p < 0.05 for each). Although PP reduced in both group (ramipril group, 60.3 ± 12.4 mm Hg to 50.4 ± 7.60 mm Hg; telmisartan group, 75.0 ± 14.0 mm Hg to 57.4 ± 15.1 mm Hg), change was statistically remarkable only in telmisartan group. During eight weeks, there was no significant changes of RHI in both groups. There was a positive relationship between decrease of PP after 8 weeks and the improvement of endothelial function only in ramipril group, but not in telmisartan group (ramipril group,r= 0.671,p =0.034; telmisartan group,r= -0.487,p =0.153).
  
  
  CONCLUSIONS
  Despite PP reduction effect favoring endothelial function, it's not correlated with RHI improvement with telmisartan. These findings suggest telmisartan itself may negatively influence endothelium dependent vasodilatation different from ramipril.
authors.affiliation: Department of Internal Medicine, Seoul Metropolitan Government Boramae Medical Center, Seoul, South Korea.|Seoul National University, College of Medicine, Seoul, South Korea.
authors.forename: You-Jeong
authors.initials: YJ
authors.lastname: Ki
authors.affiliation: Department of Internal Medicine, Seoul Metropolitan Government Boramae Medical Center, Seoul, South Korea.|Seoul National University, College of Medicine, Seoul, South Korea.
authors.forename: Jae-Bin
authors.initials: JB
authors.lastname: Seo
authors.affiliation: Department of Internal Medicine, Seoul Metropolitan Government Boramae Medical Center, Seoul, South Korea.|Seoul National University, College of Medicine, Seoul, South Korea.
authors.forename: Hack-Lyoung
authors.initials: HL
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Seoul Metropolitan Government Boramae Medical Center, Seoul, South Korea.|Seoul National University, College of Medicine, Seoul, South Korea.
authors.forename: Woo-Hyun
authors.initials: WH
authors.lastname: Lim
authors.affiliation: Department of Internal Medicine, Seoul Metropolitan Government Boramae Medical Center, Seoul, South Korea.|Seoul National University, College of Medicine, Seoul, South Korea.
authors.forename: Hye Yeon
authors.initials: HY
authors.lastname: Seo
authors.affiliation: Department of Internal Medicine, Seoul Metropolitan Government Boramae Medical Center, Seoul, South Korea.|Seoul National University, College of Medicine, Seoul, South Korea.
authors.forename: Jin Yong
authors.initials: JY
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, Seoul Metropolitan Government Boramae Medical Center, Seoul, South Korea.|Seoul National University, College of Medicine, Seoul, South Korea.
authors.forename: Woo-Young
authors.initials: WY
authors.lastname: Chung
keywords: Endothelial function; Pulse pressure; Ramipril; Reactive hyperemia index; Telmisartan