Comparison of the effects of antihypertensive treatment with angiotensin II blockade and beta-blockade on carotid wall structure and haemodynamics: protocol and baseline demographics.
Several systemic factors have been shown to contribute to the acceleration of large vessel atheroma. Correction of these factors leads to a reduction in the progression of plaque formation and associated arterial wall thickness. Atheroma remains, however, a focal disease, developing at characteristic sites within the arterial tree. These sites are typically at areas of vessel branching or marked curvature, and correspond to regions of high tensile stress and low sheer stress, leading to the hypothesis that local haemodynamic factors and vessel wall mechanics potentiate the focal development of atheroma. Current assessment of vascular haemodynamics suffers from an inability to handle complex flow, and does not allow accurate determination of locally varying flow, and shear stress patterns. The application of computational fluid dynamic (CFD) flow simulation techniques to ultrasound and local pressure data, however, allows a comprehensive, non-invasive appraisal of haemodynamic flow parameters to be performed. The Candesartan cilexetil and Atenolol Carotid Haemodynamic Endpoint Trial (CACHET) study compares the effects of two antihypertensive regimens, one b-blocker-based, the other angiotensin receptor blocker based, on carotid intima-media thickness. The collection of ultrasound and pressure data on each subject provides a unique opportunity to apply these data to the CFD model to study the effects of these antihypertensive regimens on local fluid dynamics. This will lead to a greater understanding of the relationship of these factors to atheroma formation and regression.
Ariff
Ben
B
Department of Clinical Pharmacology Therapeutics, St Marys Hospital, Imperial College, London, UK. b.ariff@ic.ac.uk
Stanton
Alice
A
Barratt
Dean
D
Augst
Alex
A
Glor
Fadi
F
Poulter
Neil
N
Sever
Peter
P
Xu
Yun
Y
Hughes
Alun
A
Thom
Simon A Mc G
SA
D000319:Adrenergic beta-Antagonists / Q000008:administration & dosage; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000804:Angiotensin II / Q000037:antagonists & inhibitors; D000959:Antihypertensive Agents / Q000008:administration & dosage*; D001161:Arteriosclerosis / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000473:pathology*; D001262:Atenolol / Q000008:administration & dosage*; D001562:Benzimidazoles / Q000008:administration & dosage*; D001713:Biphenyl Compounds / Q000008:administration & dosage*; D001794:Blood Pressure / Q000187:drug effects; D018660:Blood Pressure Monitoring, Ambulatory; D017536:Carotid Artery, Common / Q000000981:diagnostic imaging / Q000473:pathology / Q000502:physiology; D002560:Cerebrovascular Circulation / Q000187:drug effects*; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D017078:Laser-Doppler Flowmetry; D008297:Male; D008365:Manometry; D008875:Middle Aged; D008955:Models, Cardiovascular; D013777:Tetrazoles; D014463:Ultrasonography
D000319:Adrenergic beta-Antagonists; D000959:Antihypertensive Agents; D001562:Benzimidazoles; D001713:Biphenyl Compounds; D013777:Tetrazoles; D000804:Angiotensin II; D001262:Atenolol; C077793:candesartan cilexetil