Carotid hemodynamic parameters in hemodialysis patients

Atherosclerotic vascular disease is a major cause of morbidity and mortality for patients with end-stage renal disease on maintenance hemodialysis. Early atherosclerotic changes of the arterial wall can be evaluated by intima-media thickness (IMT), presence and structure of plaques and parameters of vascular resistance. The aim of the present study has been to investigate the relationship between carotid IMT and pulsatility index (PI) or resistive index (RI) values in hemodialysis patients.

We studied 36 hemodialysis patients (21 female, 15 male; median age 39.5 years, IQR 33.0-54.7 years) and 38 healthy volunteers (20 women, 18 men; median age 41.0 years IQR 32.5-53.5 years). All subjects underwent ultrasonography of common carotid artery, with determination of IMT, PI and RI.

Bilateral and mean carotid IMT were found to be significantly higher in hemodialysis patients than in the control group (P<0.0001). Right and left carotid artery RI values were determined to be lower in hemodialysis patients than in the control group (P=0.007 for both). Similarly, right and left carotid PI values were also determined significantly lower in the hemodialysis group (P=0.005 and P=0.004, respectively). There was a moderate negative correlation between the right carotid IMT and right PI (r=-0.258, P=0.026).

In contrast to previous studies in patients with diabetes, hypertension or cerebrovascular disease, PI and RI values decrease when IMT increases in hemodialysis patients. This finding may be a result of peripheral vasodilatation secondary to anemia in hemodialysis patients.