title: Angiotensin receptor blocker improves coronary flow velocity reserve in hypertensive patients: comparison with calcium channel blocker.
abstract: Large-scale clinical studies have indicated that angiotensin receptor blockers (ARBs) have beneficial effects against cardiovascular diseases. We designed this study to compare the effects of an ARB and a calcium channel blocker (CCB) on coronary flow velocity reserve (CFVR), a predictor of cardiovascular events, as estimated using transthoracic Doppler echocardiography. Sixteen hypertensive patients (63.1+/-9.6 years old; 10 males) were randomly allocated in a double-blind fashion to valsartan (n=8, 40-80 mg/day) or nifedipine (n=8, 20-40 mg/day) groups. Age- and gender-matched subjects without hypertension were enrolled as a control group (n=12). CFVR was calculated by dividing the adenosine triphosphate-induced hyperemic flow velocity by the basal flow velocity in the left anterior descending coronary artery. Baseline characteristics and reduction in systolic and diastolic blood pressure after 6 months were similar in both groups. CFVR in the valsartan group increased from 2.34+/-0.38 to 3.10+/-0.84 at 2 months (p<0.05), and to 3.04+/-1.09 at 6 months (p<0.01). Both values became comparable to that in the control group (2.81+/-0.60). CFVR in the valsartan group was significantly higher (p<0.001) than that in the nifedipine group, which was little changed at 6 months. This discrepancy was derived from the significant increase of hyperemic velocity in the valsartan group, from 36.6+/-17.3 cm/s to 41.1+/-12.7 cm/s at 2 months, and to 48.1+/-20.2 cm/s at 6 months. We concluded that the ARB valsartan not only reduced high blood pressure but improved CFVR in hypertensive patients. However, these effects were not seen with the CCB nifedipine.
authors.affiliation: The Second Department of Internal Medicine, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan.
authors.forename: Fumihiko
authors.initials: F
authors.lastname: Kamezaki
authors.forename: Hiromi
authors.initials: H
authors.lastname: Tasaki
authors.forename: Kazuhito
authors.initials: K
authors.lastname: Yamashita
authors.forename: Kiyoko
authors.initials: K
authors.lastname: Shibata
authors.forename: Noriko
authors.initials: N
authors.lastname: Hirakawa
authors.forename: Masato
authors.initials: M
authors.lastname: Tsutsui
authors.forename: Ryouji
authors.initials: R
authors.lastname: Kouzuma
authors.forename: Toshihisa
authors.initials: T
authors.lastname: Nagatomo
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Adachi
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Otsuji
mesh_terms: D000368:Aged; D047228:Angiotensin II Type 1 Receptor Blockers / Q000008:administration & dosage*; D001783:Blood Flow Velocity / Q000187:drug effects; D001794:Blood Pressure / Q000187:drug effects; D002121:Calcium Channel Blockers / Q000008:administration & dosage*; D003326:Coronary Circulation / Q000187:drug effects*; D004452:Echocardiography; D005260:Female; D006801:Humans; D006940:Hyperemia / Q000503:physiopathology; D006973:Hypertension / Q000188:drug therapy* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D009543:Nifedipine / Q000008:administration & dosage*; D013777:Tetrazoles / Q000008:administration & dosage*; D014633:Valine / Q000008:administration & dosage / Q000031:analogs & derivatives*; D000068756:Valsartan
chemical_list: D047228:Angiotensin II Type 1 Receptor Blockers; D002121:Calcium Channel Blockers; D013777:Tetrazoles; D000068756:Valsartan; D014633:Valine; D009543:Nifedipine