Radial artery hypertrophy occurs in coronary atherosclerosis and is independent of blood pressure

Abstract

Endothelial dysfunction, believed to underlie the structural changes of atherosclerosis, is a systemic phenomenon. Despite this, the radial artery has been considered as devoid of atherosclerosis and is commonly used as a conduit in coronary artery bypass grafting (CABG). Recently, histological study has shown intimal hyperplasia and other structural changes consistent with early atherosclerosis in the radial artery. The objective of the present study was to determine if structural changes in the radial artery could be detected in vivo in patients with coronary atherosclerosis. Using high resolution echo-tracking, measurements of radial artery internal diameter, wall thickness and wall cross-sectional area were made in 25 patients awaiting CABG and in 20 controls. Digital and brachial blood pressures were also recorded. Mean arterial pressures did not differ between the patient and control groups. All measures of wall thickness were greater in the patient than the control group. Neither current arterial pressures nor past history of hypertension correlated with wall thickness. Using a model of analysis of covariance, coronary artery disease was the best single predictor of intima-media thickness, R(2)=48%, n=44, P<0.0005. We concluded that increased radial artery wall thickness can be demonstrated in vivo in patients with coronary atherosclerosis. This is a novel observation which seems to be independent of blood pressure, and is consistent both with the hypothesis of systemic endothelial dysfunction leading to systemic structural changes and also to the recent histological evidence for atherosclerotic changes in this vessel.

The Impact of Coronary Artery Disease Risk Factors on Inner Diameters of Right Radial Arteries

“…12 Although the media-to-lumen ratio increases, the medial cross-sectional area remains unchanged, resulting in a decrease in the inner diameter of the vessel. 12,13 In our study we found that there was a strong negative correlation between the inner diameters of RRAs and the increase of risk factor scores. It meant that the increase of the risk factor numbers were correlated with the decrease of the inner diameters of RRAs.…”

“…Mourad et al 17 previously reported that the compliance of radial arteries in hypertensive patients was not significantly different from those with normotension, despite increased wall thickness in the hypertensive patients. Mackay et al 13 assumed that radial artery intima-media hypertrophy was likely to be independent of blood pressure effects, and it was suspected due to endothelial dysfunction. Loh et al 18 found that risk factors that positively affected the size of the radial artery were sex, hypertension, and hyperlipidemia.…”

Radial Artery Graft for Coronary Artery Bypass Surgery: Biological Characteristics and Clinical Outcome

“…Thus, the RA may be vulnerable to atherosclerosis. In fact, atherosclerotic change is more prevalent in the RA (5% to 10% incidence) than in the ITA (<1%) at the time of surgery 48‐51,53,63‐66 . Vascular wall morbidity is exacerbated in patients with diabetes mellitus or renal dysfunction 67,68 .…”

Obese children show increased intimal wall thickness and decreased pulse wave velocity

“…Although the radial arteries (RAs) are not prone to atherosclerosis, it has been shown that RA hypertrophy occurs in patients with coronary atherosclerosis who are waiting for coronary bypass surgery (MacKay et al, 2001). Hitherto, detailed in vivo descriptions of RA morphology with separation of the tunica intima from underlying structures were not possible in humans.…”

“…Although the radial arteries (RAs) are not prone to atherosclerosis, it has been shown that RA hypertrophy occurs in patients with coronary atherosclerosis who are waiting for coronary bypass surgery (MacKay et al. , 2001).…”