Olmesartan improves coronary flow reserve of hypertensive patients using coronary magnetic resonance imaging compared with amlodipine.
OBJECTIVE
Hypertension impairs coronary endothelial cell function, coronary microvascular function and the coronary flow (CF) reserve (CFR). Angiotensin II receptor blockers (ARBs) have been reported to possibly improve coronary endothelial function and coronary microvascular function. The purpose of this study was to determine whether treatment with the ARB olmesartan was more effective for improving CFR than the calcium channel blocker amlodipine.


METHODS
Twenty patients with untreated essential hypertension (M/F = 13/7, aged 55.6 ± 11.6 years) were randomly assigned to treatment with either olmesartan (n = 10) or amlodipine (n = 10) for 6 months. CF was measured in the proximal left anterior descending artery by magnetic resonance imaging before and during intravenous infusion of adenosine. CFR was calculated as the ratio of the hyperemic to baseline diastolic peak flow before and after 6 months of treatment.


RESULTS
The extent of systolic blood pressure reduction was similar in both groups (-40.0 ± 19.1 vs. -48.8 ± 14.7 mm Hg, p = 0.26). The olmesartan group showed significant improvement of CFR (from 1.9 ± 1.0 to 3.1 ± 1.1, p = 0.005), but this did not occur in the amlodipine group.


CONCLUSIONS
Olmesartan, but not amlodipine, improves CFR in hypertensive patients.
Gunma Prefectural Cardiovascular Center, Maebashi, Japan. toyama-toyama@cvc.pref.gunma.jp
Takuji
T
Toyama
Chizuru
C
Sato
Keiko
K
Koyama
Shu
S
Kasama
Jun
J
Murakami
Eiji
E
Yamashita
Ren
R
Kawaguchi
Hitoshi
H
Adachi
Hiroshi
H
Hoshizaki
Shigeru
S
Oshima
D000241:Adenosine / Q000494:pharmacology; D000328:Adult; D000368:Aged; D017311:Amlodipine / Q000627:therapeutic use*; D000959:Antihypertensive Agents / Q000627:therapeutic use*; D003326:Coronary Circulation / Q000187:drug effects*; D004452:Echocardiography / Q000379:methods; D005260:Female; D006801:Humans; D006973:Hypertension / Q000188:drug therapy* / Q000503:physiopathology; D007093:Imidazoles / Q000627:therapeutic use*; D018810:Magnetic Resonance Angiography / Q000379:methods; D008297:Male; D008875:Middle Aged; D013318:Stroke Volume / Q000187:drug effects; D013777:Tetrazoles / Q000627:therapeutic use*; D014665:Vasodilator Agents / Q000494:pharmacology; D016277:Ventricular Function, Left / Q000187:drug effects
D000959:Antihypertensive Agents; D007093:Imidazoles; D013777:Tetrazoles; D014665:Vasodilator Agents; D017311:Amlodipine; C437965:olmesartan; D000241:Adenosine