Effect of Beta-Blocker Cardioselectivity on Vascular Refilling in Hemodialysis Patients

Abstract

Background: β-Blockers are the most frequently prescribed cardioprotective drugs in hemodialysis (HD) patients, despite their weak evidence. We sought to evaluate the effects of β-blockers on vascular refilling during HD treatments and examine whether carvedilol, for being noncardioselective and poorly dialyzable, associates more impact than others.

Methods: The study was performed in a cohort of maintenance HD patients from a tertiary center. All patients had previous β-blocker prescription. We conducted a prospective crossover study and measured vascular refilling volume (Vref) and vascular refilling fraction (Fref) in 2 circumstances: under β-blocker treatment (βb profile) and without β-blocker effect (non-βb profile).

Results: Twenty patients were included, 10 of whom were treated with carvedilol. Predialysis values were comparable between the 2 profiles. Although the βb profile showed lower Vref and higher ABV drop, these differences did not reach statistical significance. Data showed an increase in Fref in the non-βb profile (70.01 ± 6.80% vs. 63.14 ± 11.65%; p = 0.015). The βb profile associated a significantly higher risk of intradialytic hypotension (IDH) (risk ratio 2.40; 95% CI: 1.04-5.55). When analyzing separately the carvedilol group, patients dialyzed under drug effect experienced a significant impairment in Vref, Fref, and refilling rate.

Conclusions: Administering β-blockers before HD associated a higher risk of IDH and a decrease in Fref. Patients dialyzed under carvedilol effect showed an impaired refilling, probably related to its noncardioselectivity and lower dializability.

Keywords: Absolute blood volume; Carvedilol; Hemodialysis; Intradialytic morbid events; Vascular refilling; β-Blocker.