Effect of hemodialysis on left ventricular performance

Systolic time intervals (STI) and echocardiograms (Echo) were performed before and 30 min after hemodialysis (H) in 19 stable patients (pts) with chronic renal failure undergoing maintenance H. The % shortening of the internal diameter (% delta D), the mean velocity of circumferential fiber shortening (VCF), and the ratio of the pre-ejection period to the left ventricular (LV) ejection time (PEP/LVET) were used as indices of LV performance; the electromechanical systole corrected for heart rate (QS2I) was used as an index of adrenergic activity. After hemodialysis, LV function was improved in 9 pts, Group (GI) and decreased in 10 pts (GII). Changes due to H are shown. The % delta D and VCF before H were normal in GI but abnormal in GII (31.6 +/- 1.4 vs 24.5 +/- 1.4 and 1.07 +/- 0.06 vs 0.88 +/- 0.04, respectively). Systolic blood pressure remained unchanged in GI but decreased in GII (-9.5 +/- 4 mm Hg, p less than 0.01). Body weight decreased significantly (p less than 0.05) and equally in both Gs (-1.2 +/- 0.03 in GI and -1.6 +/- 0.03 in GII). Serum electrolytes, creatinine, and hemoglobin were identical in both Gs before and after H. LV performance improved in pts with LV dysfunction before H, but decreased in pts with normal LV function before H. The decreased afterload in GII and the different effect of alterations in preload and afterload in the failing and normal LV most likely account for these changes. STI and Echo provide simple techniques to assess changes in LV function due to H and one is complementary to the other.