Echocardiographic hemodynamic study during ultrafiltration sequential dialysis

Cardiac performance and morphology in end-stage renal disease

Patients with end-stage renal disease (ESRD) experience a variety of hemodynamic and metabolic abnormalities that predispose to alterations in cardiac performance and morphology. High cardiac output related to renal anemia, hypertension, volume overload, and the arteriovenous fistula (in patients on hemodialysis) predispose to eccentric left ventricular (LV) hypertrophy. Hypertension, aortic stiffness, and aortic stenosis predispose to concentric LV hypertrophy. Most ESRD patients have a hybrid form of LV hypertrophy. LV hypertrophy is commonly accompanied by LV diastolic dysfunction. LV systolic dysfunction is less common. Newer dialytic techniques, excellent control of hypertension, and correction of renal anemia produce regression of LV hypertrophy. The effect of these interventions on LV systolic and diastolic function is less well established. Alterations in serum calcium, choice of dialysate base, hypoxia, and comorbid conditions may influence the effects of dialysis (particularly hemodialysis) on LV function. A variety of negative inotropic drugs may depress LV function in patients with ESRD.

Comparative cardiac effects of hemodialysis and continuous ambulatory peritoneal dialysis

To assess the comparative cardiac effects of hemodialysis and continuous ambulatory peritoneal dialysis (CAPD), we performed M-mode echocardiography prior to and immediately following hemodialysis on 56 patients and during the dwell phase of CAPD on 39 patients. Hemodialysis produced a significant increase in the mean velocity of circumferential fiber shortening (VCF, an index of left ventricular systolic function) in patients with low VCF prior to dialysis, but resulted in no significant change in VCF in patients with normal predialysis VCF. Hemodialysis produced a significant increase in VCF in patients with a normal predialysis left ventricular end-diastolic volume index (LVEDVI), but resulted in no significant change in VCF in patients with left ventricular dilatation prior to dialysis. Hemodialysis produced a significant decrease in mean LVEDVI and mean stroke index, but resulted in no significant change in mean cardiac index due to a reflex increase in heart rate. Mean LVEDVI, mean stroke index, and VCF values in patients on CAPD were not significantly different from those observed immediately following hemodialysis. Mean cardiac index and mean heart rate were significantly lower in CAPD patients than in posthemodialysis patients. Pericardial effusion was observed in 25% of hemodialysis patients and 5% of CAPD patients (p less than 0.05). We conclude (1) the effects of hemodialysis on left ventricular performance are variable and depend in part on predialysis left ventricular volume and left ventricular systolic function, (2) except for a lower cardiac index, left ventricular hemodynamics for CAPD patients resemble those of posthemodialysis patients, and (3) pericardial effusion occurs with significantly higher frequency in patients on hemodialysis than in those on CAPD.

Plasma volume recovery after ultrafiltration in patients with chronic renal failure

We studied the effect of standardized ultrafiltration (UF, 2 liters in 60 min) on plasma volume (PV, 131I-albumin space) and its recovery, with special reference to the tissue hydration before UF. Twenty-one UF sessions were performed in 15 patients with endstage renal failure. The PV reduction, which varied considerably, was maximal at the end of UF (range, -0.7 to -21.9%); after that PV recovered reaching a plateau in the second hour after UF. A highly significant negative correlation was found between the interstitial fluid volume (IVF, calculated from 82Br space-PV) and the PV reduction at this stage (r = -0.89, P less than 0.0001). Despite avoidance of major changes in total extracellular fluid in the next 24 hr, a further restoration of PV took place which was partial in subjects with normal tissue hydration, but complete or even excessive in grossly overfilled subjects. This PV repletion was accompanied by an increase in the intravascular mass of albumin (P less than 0.02). The negative correlation between initial IFV and PV change persisted after 24 hr (r = -0.83, P less than 0.0005). In most occasions the blood pressure fell, but only in eight occasions frank hypotension followed. Heart rate remained remarkably unaltered, even during hypotensive episodes. Changes in plasma renin activity followed no uniform pattern. Our findings indicate that the tissue hydration state has a strong influence on changes in PV during fluid removal and the subsequent repletion of PV.

Analysis of increased myocardial contractility during sodium acetate infusion in humans

To analyze the reported effects of acetate on left ventricular (LV) contractility during dialysis, LV function was studied before and after a 20-min sodium acetate (Na Ac) infusion (0.06 mmoles X kg-1 X min-1) in seven patients with heart rate (HR) controlled by atrial pacing. Angiographically determined LV volumes and LV pressures were used to calculate the LV function indices. A plasma acetate concentration of 3.13 +/- 1.05 (SD) mmoles X liter-1 induced an increase in cardiac index from 3.8 +/- 0.6 to 4.4 +/- 0.6 (SD) liter X min-1 X m-2 (P less than 0.01) and a rise in total body O2 consumption from 7.47 +/- 1.28 to 8.67 +/- 1.66 mmoles X min-1 X m-2 (P less than 0.05); there was no alteration of the volume elastic constant, of the end diastolic stress, and of the end systolic stress. There was an increase of the ejection fraction from 0.44 +/- 0.10 to 0.51 +/- 0.09 (P less than 0.01), the maximum velocity of shortening (Vmax, sec-1) from 1.37 +/- 0.25 to 1.55 +/- 0.28 (P less than 0.05), and of the end systolic stress-end systolic volume ratio (g X cm-2 X ml-1) from 2.99 +/- 0.76 to 3.40 +/- 0.98 (P less than 0.01). Hence, the enhancement of these indices was not the consequence of any alteration of HR, preload, or afterload.(ABSTRACT TRUNCATED AT 250 WORDS)