Increase in serum ionized calcium during diffusive dialysis does not affect left ventricular diastolic function.

An increase in serum Ca2+ during hemodialysis (HD) may lead to impaired left ventricular (LV) relaxation. Since LV diastolic function assessment in dialysis patients is hampered by preload dependence of Doppler measurements, we tested the effect of HD without ultrafiltration (UF) on these measurements. Transmitral E and A velocities, and mitral annulus e and a velocities were measured in 10 patients before and after 1 h of HD without UF. Dialysate Ca2+ was 1.75 mmol/l. Serum Ca2+ after 1 h (1.31 mmol/l; 1.28-1.46 mmol/l) was higher (p = 0.002) than before HD (1.24 mmol/l; 1.09-1.32 mmol/l). E/A (0.8; 0.4-2.8) and e/a (0.7; 0.4-1.3) after 1 h were not different than E/A (0.8; 0.6-5.1) and e/a (0.7; 0.4-1.8) before HD. The increase in serum Ca2+ does not lead to a change in Doppler parameters of LV diastolic function. Changes in these parameters after combined HD-UF are related to preload, not to serum Ca2+.