12 research outputs found

    Hypochloremia, diuretic resistance, and outcome in patients with acute heart failure

    Get PDF
    Background—Chloride plays a role in renal salt sensing, neurohormonal activation, and regulation of diuretic targets, and hypochloremia predicts mortality in acute heart failure (AHF). AHF therapies, such as diuretics, alter chloride homeostasis. We studied the association between (changes in) chloride levels and diuretic responsiveness, decongestion, and mortality in patients with AHF. Methods and Results—Patients hospitalized for AHF in the PROTECT trial (n=2033) with serum chloride levels within 24 hours of admission and 14 days later were studied (n=1960). Hypochloremia was defined as serum chloride <96 mEq/L. Mean baseline chloride was 100.8±5.0 mEq/L. Low baseline chloride was associated with high bicarbonate, poor diuretic response, less hemoconcentration, and worsening heart failure (all P<0.01). Newly developed hypochloremia at day 14 was common and associated with a decline in renal function and an increase in blood urea nitrogen (P<0.01). In multivariable analyses, chloride measured at day 14, but not baseline chloride, was strongly and independently associated with mortality through 180 days (hazard ratio per unit decrease: 1.07 [1.03–1.10]; P<0.001). In comparison, sodium was not significantly associated with mortality after multivariable adjustment at any time point. Hypochloremia at baseline that resolved was not associated with mortality (P=0.55), but new or persistent hypochloremia at day 14 was associated with increased mortality (hazard ratio: 3.11 [2.17–4.46]; P<0.001). Conclusions—Low serum chloride at AHF hospital admission was strongly associated with impaired decongestion. New or persistent hypochloremia 14 days later was independently associated with reduced survival, whereas hypochloremia that resolved by day 14 was not. Clinical Trial Registration—URL: http://www.clinicaltrials.gov. Unique identifier: NCT00354458

    The risk of death associated with proteinuria in heart failure is restricted to patients with an elevated blood urea nitrogen to creatinine ratio

    No full text
    Background: Renal dysfunction (RD) is associated with reduced survival in HF; however, not all RD is mechanistically or prognostically equivalent. Notably, RD associated with "pre-renal" physiology, as identified by an elevated blood urea nitrogen to creatinine ratio (BUN/Cr), identifies a particularly high risk RD phenotype. Proteinuria, another domain of renal dysfunction, has also been associated with adverse events. Given that several different mechanisms can cause proteinuria, we sought to investigate whether the mechanism underlying proteinuria also affects survival in HF. Methods and Results: Subjects in the Studies of Left Ventricular Dysfunction (SOLVD) trial with proteinuria assessed at baseline were studied (n = 6439). All survival models were adjusted for baseline characteristics and estimated glomerular filtration rate (eGFR). Proteinuria (trace or 1+) was present in 26% and associated with increased mortality (HR = 1.2; 95% CI, 1.1-1.3, p = 0.006). Proteinuria >1+ was less common (2.5%) but demonstrated a stronger relationship with mortality (HR = 1.9; 95% CI, 1.5-2.5, p <0.001). In patients with BUN/Cr in the top tertile (>= 17.3), any proteinuria (HR = 1.3; 95% CI, 1.1-1.5, p = 0.008) and >1+ proteinuria (HR = 2.3; 95% CI, 1.7-3.3, p <0.001) both remained associated with mortality. However, in patients with BUN/Cr in the bottom tertile (1+ proteinuria (HR = 1.3; 95% CI, 0.79-2.2, p = 0.29, p interaction = 0.036) were not associated with worsened survival. Conclusion: Analogous to a reduced eGFR, the mechanism underlying proteinuria in HF may be important in determining the associated survival disadvantage. (C) 2016 Elsevier Ireland Ltd. All rights reserved

    Reduced Cardiac Index Is Not the Dominant Driver of Renal Dysfunction in Heart Failure

    No full text
    BACKGROUND: It is widely believed that reduced cardiac index (CI) is a significant contributor to renal dysfunction in patients with heart failure (HF). However, recent data have challenged this paradigm. OBJECTIVES: We sought to determine the relationship between CI and renal function in a multicenter population of HF patients undergoing pulmonary artery catheterization (PAC). METHODS: Patients undergoing PAC in either the randomized or registry portions of the ESCAPE (Evaluation Study of Congestive Heart Failure and Pulmonary Artery Catheterization Effectiveness) trial were included (n = 575). We evaluated associations between CI and renal function across multiple subgroups and assessed for nonlinear, threshold, and longitudinal relationships. RESULTS: There was a weak but statistically significant inverse correlation between CI and estimated glomerular filtration rate (eGFR), such that higher CI was paradoxically associated with worse eGFR (r = −0.12; p = 0.02). CI was not associated with blood urea nitrogen (BUN) or the BUN to creatinine ratio. Similarly, no significant associations were observed between CI and better renal function across multiple subgroups defined by indications for PAC or hemodynamic, laboratory, or demographic parameters. A nonlinear or threshold effect could not be identified. In patients with serial assessments of renal function and CI, we were unable to find within-subject associations between change in CI and eGFR using linear mixed modeling. Neither CI nor change in CI was lower in patients developing worsening renal function (p ≥ 0.28). CONCLUSIONS: These results reinforce evidence that reduced CI is not the primary driver for renal dysfunction in patients hospitalized for HF, irrespective of the degree of CI impairment or patient subgroup analyzed

    Renal tubular resistance is the primary driver for loop diuretic resistance in acute heart failure

    Get PDF
    Background: Loop diuretic resistance is a common barrier to effective decongestion in acute heart failure (AHF), and is associated with poor outcome. Specific mechanisms underlying diuretic resistance are currently unknown in contemporary AHF patients. We therefore aimed to determine the relative importance of defects in diuretic delivery vs. renal tubular response in determining diuretic response (DR) in AHF. Methods and results: Fifty AHF patients treated with intravenous bumetanide underwent a 6-h timed urine collection for sodium and bumetanide clearance. Whole-kidney DR was defined as sodium excreted per doubling of administered loop diuretic and represents the sum of defects in drug delivery and renal tubular response. Tubular DR, defined as sodium excreted per doubling of renally cleared (urinary) loop diuretic, captures resistance specifically in the renal tubule. Median administered bumetanide dose was 3.0 (2.0-4.0) mg with 52 (33-77)% of the drug excreted into the urine. Significant between-patient variability was present as the administered dose only explained 39% of variability in the quantity of bumetanide in urine. Cumulatively, factors related to drug delivery such as renal bumetanide clearance, administered dose, and urea clearance explained 28% of the variance in whole-kidney DR. However, resistance at the level of the renal tubule (tubular DR) explained 71% of the variability in whole-kidney DR. Conclusion: Defects at the level of the renal tubule are substantially more important than reduced diuretic delivery in determining diuretic resistance in patients with AHF

    Hypochloremia and Diuretic Resistance in Heart Failure: Mechanistic Insights

    No full text
    Background-Recent epidemiological studies have implicated chloride, rather than sodium, as the driver of poor survival previously attributed to hyponatremia in heart failure. Accumulating basic science evidence has identified chloride as a critical factor in renal salt sensing. Our goal was to probe the physiology bridging this basic and epidemiological literature. Methods and Results-Two heart failure cohorts were included: (1) observational: patients receiving loop diuretics at the Yale Transitional Care Center (N=162) and (2) interventional pilot: stable outpatients receiving >= 80 mg furosemide equivalents were studied before and after 3 days of 115 mmol/d supplemental lysine chloride (N=10). At the Yale Transitional Care Center, 31.5% of patients had hypochloremia (chloride Conclusions-Hypochloremia is associated with neurohormonal activation and diuretic resistance with chloride depletion as a candidate mechanism. Sodium-free chloride supplementation was associated with increases in serum chloride and changes in several cardiorenal parameters
    corecore