Effects of acetate and bicarbonate dialysate on left ventricular performance.

Whether bicarbonate dialysis (BiHD) improves left ventricular (LV) function more than acetate dialysis (AcHD) and whether AcHD exerts a negative inotropic effect remains controversial. To address this question, the LV contractile responses to both dialysate buffers were tested in six stable chronic dialysis patients not taking any cardiac or antihypertensive medicines. The patients were studied with echocardiography before and after an isovolemic dialysis (no weight change) with either buffer, and neither heart rate nor blood pressure were significantly altered during either procedure. The patients were studied at three different filling volumes so that LV function curves could be constructed. Both dialysates were associated with comparable and significant changes in LV end systolic volume (AcHD, 55 +/- 5 to 49 +/- 5 mL, P less than .001; BiHD, 56 +/- 5 to 49.5 +/- 5 mL, P less than .001), stroke volume (AcHD, 88 +/- 7 to 97 +/- 5 mL, P less than .01; BiHD, 89 +/- 7 to 97 +/- mL, P less than .05), and LV ejection fraction (AcHD, 60 +/- 7% to 65 +/- 8%, P less than .05; BiHD, 60 +/- 3 to 67 +/- 2%, P less than .001). In addition, the mean velocity of circumferential fiber shortening (VCF), an index of ventricular contractility, also increased significantly after dialysis with both dialysates (AcHD, .96 +/- .08 to 1.20 +/- .15, P less than .001; BiHD, .93 +/- .09 to 1.29 +/- .11, P less than .001). Finally, both dialysates were associated with upward shifts in the LV function curve of a similar magnitude.(ABSTRACT TRUNCATED AT 250 WORDS)