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Left atrial volume (LAV), as indexed by height(2.7), has recently emerged as an useful echocardiographic measurement to refine the estimate of cardiovascular (CV) risk in ESRD. Whether progression or regression in LAV has prognostic value in patients with ESRD is still unknown. The prognostic value for CV events of changes in LAV was tested in a cohort of 191 dialysis patients. Echocardiography was performed twice, 17 +/- 2 mo apart. Changes in LAV that occurred between the second and the first echocardiographic studies were used to predict CV events during the ensuing 27 +/- 13 mo. During the follow-up, there was a significant increase in LAV (from 10.5 +/- 5.0 to 11.6 +/- 5.6 ml/m(2.7); P < 0.001). After the second echocardiographic study, 76 patients died (52 [68%] of CV causes) and 33 had nonfatal CV events. The independent association between changes in LAV and CV events was analyzed in a multiple Cox regression model taking into account a series of potential confounders, including baseline LAV and left ventricular mass and geometry. In these models, a 1-ml/m(2.7) per yr increase in LAV was associated with a 12% increase in the relative risk for fatal and nonfatal CV events (P < 0.001). Changes in LAV predict incident CV events in dialysis patients independent of the corresponding baseline measurement and of left ventricular mass. Monitoring LA size by echocardiography is useful for monitoring CV risk in patients with ESRD.

Although it is well established that compromised systolic function predicts cardiovascular (CV) complications in symptomatic and asymptomatic patients with ESRD, it still is unknown whether repeated echocardiographic measurements of systolic function in asymptomatic patients with ESRD is useful for monitoring the evolution of cardiomyopathy in these patients. The prognostic value for CV events of changes in systolic function, as measured by midwall fractional shortening (mwFS) in a cohort of 191 dialysis patients, was tested. Echocardiography was performed twice, 17 ± 2 mo apart. Changes in mwFS (ch-mwFS) that occurred between the second and the first echocardiographic studies then were used to predict CV events during the ensuing 27 ± 13 mo. After the second echocardiographic study, 85 patients had incident CV events. In a Kaplan-Meier analysis, there was a graded increase in the risk for fatal and nonfatal CV events across ch-mwFS quartiles ( P = 0.005). On multivariate Cox regression analysis, ch-mwFS maintained an independent association with CV outcomes. In this analysis, the risk for CV events was 51% lower in patients who manifested an increase in mwFS (hazard ratio 0.49; 95% confidence interval 0.27 to 0.88; P = 0.02) than in those who had a decrease in mwFS. Changes in mwFS have an independent prognostic value for CV events, and periodic echocardiographic studies of systolic function are useful for monitoring asymptomatic dialysis patients.

Patients with end-stage renal disease (ESRD) are at high risk for heart failure, but the prevalence and the prognostic value of asymptomatic systolic dysfunction in these patients are unknown. In this prospective cohort study, the authors have therefore assessed by echocardiography the prevalence and the prognostic value of systolic function as estimated by ejection fraction (EF), fractional shortening at endocardial level (endoFS), and at midwall (mwFS), in a cohort of 254 asymptomatic dialysis patients. Systolic dysfunction had a prevalence rate of 26% by endoFS and of 48% by mwFS. During the follow-up period, 125 patients had one or more fatal and nonfatal CV events. On multivariate COX regression analysis, the three LV systolic function indicators were independently associated with incident fatal and nonfatal CV events, and there were no differences in the predictive power of these indicators (P > 0.30). The prediction power of LV function indicators was largely independent of traditional and novel risk factors in ESRD such as C-reactive protein and asymmetric dimethyl arginine (ADMA). ADMA was significantly related with LV function indicators as well as with mortality and incident CV events, but these links were much reduced (P = NS) in models including LV function indicators. Of note, the risk of CV events was minimal in patients with normal LV mass and function, intermediate in patients with either LVH or systolic dysfunction, and maximal in patients displaying both alterations. The study of myocardial contractility by echocardiography provides prognostic information independently of LV mass and other risk factors in ESRD. Risk stratification by simple systolic function parameters may prove useful in secondary prevention strategies in these patients.

High sympathetic activity and alterations in nitric oxide synthesis attributable to accumulation of the endogenous nitric oxide synthase inhibitor asymmetric dimethylarginine (ADMA) have recently been identified as potential causal mechanisms for the high cardiovascular mortality rates among patients with ESRD. The link between these risk factors has not been studied. Therefore, the relationship between plasma norepinephrine (NE) and ADMA levels was examined in a large cohort of hemodialysis patients (n = 224), and whether these factors interacted in predicting all-cause mortality and new cardiovascular event rates among those patients was investigated. Plasma ADMA levels were strongly associated with plasma NE levels (P < 0.001) and to a lesser extent with heart rate (P < 0.01). In multivariate analyses, the ADMA-NE correlation was observed to be independent of age, gender, serum albumin levels, arterial pressure and antihypertensive treatment, duration of dialysis treatment, diabetes mellitus, and other risk factors. NE was an independent significant predictor of both death and cardiovascular events in Cox models not including ADMA. However, when ADMA was introduced into those models, NE became a largely nonsignificant predictor of those outcomes, whereas plasma ADMA levels emerged as a highly significant predictor of both death (P < 0.001) and cardiovascular events (P < 0.001). These findings suggest that ADMA is an intervening factor in the causal pathway leading to those outcomes. Plasma NE and ADMA concentrations are strongly related among patients with ESRD. These two factors are likely to be involved in the same causal pathway leading to death and cardiovascular events among those patients.

This study was designed to investigate the relationship among brain natriuretic peptide (BNP) and atrial natriuretic peptide (ANP) and left ventricular mass (LVM), ejection fraction, and LV geometry in a large cohort of dialysis patients without heart failure (n = 246) and to test the prediction power of these peptides for total and cardiovascular mortality. In separate multivariate models of LVM, BNP and ANP were the strongest independent correlates of the LVM index. In these models, the predictive power of BNP was slightly stronger than that of ANP. Both natriuretic peptides also were the strongest independent predictors of ejection fraction, and again BNP was a slightly better predictor of ejection fraction than ANP. In separate multivariate Cox models, the relative risk of death was significantly higher in patients of the third tertile of the distribution of BNP and ANP than in those of the first tertile (BNP, 7.14 [95% confidence interval (CI), 2.83 to 18.01, P = 0.00001]; ANP, 4.22 [95% CI, 1.79 to 9.92, P = 0.001]), and a similar difference was found for cardiovascular death (BNP, 6.72 [95% CI, 2.44 to 18.54, P = 0.0002]; ANP, 3.80 [95% CI, 1.44 to 10.03, P = 0.007]). BNP but not ANP remained as an independent predictor of death in a Cox's model including LVM and ejection fraction. Cardiac natriuretic peptides are linked independently to LVM and function in dialysis patients and predict overall and cardiovascular mortality. The measurement of the plasma concentration of BNP and ANP may be useful for risk stratification in these patients.