STUDIES OF THE VESSEL WALL PROPERTIES IN HEMODIALYSIS-PATIENTS

Compliance is an important property of the arterial system and abnorma lities in compliance can greatly affect cardiovascular function. The e lastic properties of the common carotid artery were therefore studied in 24 normotensive hemodialysis patients and 24 healthy normotensives using a noninvasive technique. The hemodialysis patients and the contr ol subjects were matched for blood pressure. Arterial distension was m easured by Doppler analysis of the vessel wall movements and blood pre ssure was recorded by finger-phlethysmography (Finapres(R)). The vesse l wall distensibility (DC: 2.49 +/- 0.23 10(-3)/mm Hg; mean +/- SEM) w as significantly reduced and the end diastolic diameter (d: 7.3 +/- 0. 3 mm) was significantly increased in younger hemodialysis patients (36 .3 +/- 2.0 years) when compared with age-related controls (DC: 3.44 +/ - 0.24 10(-3)/mm Hg; d: 6.3 +/- 0.3 mm; mean +/- SEM). In older hemodi alysis patients (60.2 +/- 2.3 years), there was no significant differe nce in vessel wall distensibility (DC: 1.55 +/- 0.15 10(-3)/mm Hg) and vessel diameter (d: 7.8 +/- 0.3 mm) as compared with age-matched cont rols (DC: 1.77 +/- 0.14 10(-3)/mm Hg; d: 7.2 +/- 0.3 mm). The results show that vessel wall distensibility of the common carotid artery is d ecreased in younger hemodialysis patients as compared with age-matched healthy subjects. The volume expanded state in hemodialysis patients cannot account for the decreased arterial distensibility, since volume depletion by hemodialysis was not associated with a significant chang e of arterial distensibility (DC 2.14 +/- 0.44 10(-3)/mm Kg before, DC 2.26 +/- 0.45 10(-3)/mm Hg after ultrafiltration, NS). The enhanced s tiffness of the arteries could contribute to the higher incidence of c ardiovascular disease in hemodialysis patients.