Effect on coronary flow velocity reserve in patients with type 2 diabetes mellitus: comparison between angiotensin-converting enzyme inhibitor and angiotensin II type 1 receptor antagonist.
BACKGROUND
The effects of angiotensin antagonists on coronary circulation in type 2 diabetes are unclear. We aimed to assess whether 4 weeks of treatment with angiotensin-converting enzyme inhibitor or angiotensin II type 1 receptor antagonist improves coronary flow velocity reserve (CFVR) in patients with type 2 diabetes.


METHODS
Twenty-four asymptomatic patients with type 2 diabetes were randomly assigned to temocapril (2 mg/d) or candesartan (8 mg/d). Coronary flow velocity reserve, calculated as the ratio of adenosine-induced hyperemic to basal coronary flow velocity, was measured with transthoracic Doppler echocardiography. Coronary flow velocity reserve measurement and venous blood sampling were performed before and after 4 weeks of treatment. We also obtained CFVR and venous blood data in the 8 healthy controls.


RESULTS
Coronary flow velocity reserve was significantly lower in patients than controls (temocapril group 2.74 +/- 0.28, candesartan group 2.65 +/- 0.30, controls 3.53 +/- 0.23, P < .0001 for both, respectively). Blood pressure was reduced in both diabetic groups (n = 12 each) similarly 4 weeks after treatment. There were no significant differences between the 2 groups in venous blood data before or after treatment. However, CFVR increased significantly in the temocapril group (2.74 +/- 0.28 to 3.31 +/- 0.36, P < .0001), but not in the candesartan group (2.65 +/- 0.30 to 2.71 +/- 0.43, P = ns).


CONCLUSIONS
Coronary flow velocity reserve in patients with type 2 diabetes improved after treatment with temocapril but not with candesartan, suggesting that angiotensin-converting enzyme inhibitor, but not angiotensin II type 1 receptor antagonist, might have beneficial effects on coronary microangiopathy associated with type 2 diabetes.
Department of Cardiovascular Science and Medicine, Chiba University Graduate School of Medicine, Chiba, Japan.
Takayuki
T
Kawata
Masao
M
Daimon
Rei
R
Hasegawa
Kiyomi
K
Teramoto
Tomohiko
T
Toyoda
Tai
T
Sekine
Kyohei
K
Yamamoto
Daigaku
D
Uchida
Toshiharu
T
Himi
Katsuya
K
Yoshida
Issei
I
Komuro
D000368:Aged; D047228:Angiotensin II Type 1 Receptor Blockers / Q000627:therapeutic use*; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000494:pharmacology / Q000627:therapeutic use*; D001562:Benzimidazoles / Q000627:therapeutic use*; D001713:Biphenyl Compounds; D001783:Blood Flow Velocity; D003326:Coronary Circulation / Q000187:drug effects*; D003924:Diabetes Mellitus, Type 2 / Q000503:physiopathology*; D003925:Diabetic Angiopathies / Q000188:drug therapy; D005080:Exercise Test; D005260:Female; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D016037:Single-Blind Method; D013777:Tetrazoles / Q000627:therapeutic use*; D013841:Thiazepines / Q000627:therapeutic use*
D047228:Angiotensin II Type 1 Receptor Blockers; D000806:Angiotensin-Converting Enzyme Inhibitors; D001562:Benzimidazoles; D001713:Biphenyl Compounds; D013777:Tetrazoles; D013841:Thiazepines; C055603:temocapril hydrochloride; C081643:candesartan