Effect of simvastatin on coronary flow reserve in patients with atherosclerosis and hypercholesterolemia: an intracoronary Doppler study.
BACKGROUND
Early stages of coronary atherosclerosis are accompanied by a functional impairment of coronary vasodilator capacity and endothelial dysfunction. Reduced coronary flow reserve has been reported in patients with hypercholesterolemia, despite angiographically normal coronary arteries. The aim of the study was to evaluate the effect of simvastatin on coronary flow reserve.


METHODS
The study was an open non-placebo-controlled serial investigation in which every patient acted as his own control: 36 male patients with hypercholesterolemia and a non-significant coronary artery lesion in a not previously revascularized coronary artery. Intracoronary Doppler measurements were performed. Coronary flow reserve, relative coronary flow reserve and average peak velocity were performed at baseline, after 3 months on a lipid-lowering diet (control period), and after another 12 months of simvastatin 40 mg/day. In the same patient cohort, significant reduction in lesion plaque plus media has been demonstrated by intravascular ultrasound.


RESULTS
Changes in coronary flow reserve were not influenced by either diet or simvastatin (2.5+/-0.6 vs. 2.6+/-0.5 vs. 2.6+/-0.6, P=ns). Maximum hyperemic flow (34.8+/-12.2 vs. 36.7+/-12.5 vs. 42.5+/-13.1, P<0.001) as well as resting flow (14.3+/-5.3 vs. 14.5+/-4.4 vs. 16.6+/-4.6, P<0.001) increased significantly after 12 months simvastatin therapy.


CONCLUSIONS
Despite plaque plus media, regression simvastatin therapy for 12 months does not affect coronary flow reserve obtained using serial intracoronary Doppler studies. Simvastatin, however, increases the hyperemic flow velocity.
Jensen
Lisette O
LO
Department of Cardiology, Odense University Hospital, Odense, Denmark. okkels@dadlnet.dk
Thayssen
Per
P
Pedersen
Knud E
KE
Haghfelt
Torben
T
D001783:Blood Flow Velocity / Q000187:drug effects*; D003324:Coronary Artery Disease / Q000150:complications / Q000188:drug therapy* / Q000503:physiopathology; D003331:Coronary Vessels / Q000000981:diagnostic imaging* / Q000187:drug effects / Q000503:physiopathology; D005500:Follow-Up Studies; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000627:therapeutic use; D006937:Hypercholesterolemia / Q000150:complications / Q000188:drug therapy* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D019821:Simvastatin / Q000627:therapeutic use*; D016896:Treatment Outcome; D018608:Ultrasonography, Doppler; D018084:Ultrasonography, Interventional / Q000379:methods*
D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D019821:Simvastatin