Abstract Background It is widely believed that a 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 This study 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 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 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.
Highlights • The validity of using changes in serum creatinine as surrogate endpoints for outcomes in heart failure was examined in 301 patients in the DOSE trial. • Decreases in serum creatinine, ...when incorrectly assumed to be linearly related to outcomes, were paradoxically associated with a substantially increased risk for adverse events. • Worsening in serum creatinine during the randomized intervention was not associated with an increase in adverse outcomes. • Improvement in renal function during the randomized intervention was strongly associated with poor outcomes. • The practice of using mild to moderate-sized changes in serum creatinine as an endpoint in heart failure clinical trials may be inappropriate.
Abstract Microbes play an important role in human health and disease. In the setting of heart failure (HF), substantial hemodynamic changes, such as hypoperfusion and congestion in the intestines, ...can alter gut morphology, permeability, function, and possibly the growth and composition of gut microbiota. These changes can disrupt the barrier function of the intestines and exacerbate systemic inflammation via microbial or endotoxin translocation into systemic circulation. Furthermore, cardiorenal alterations via metabolites derived from gut microbiota can potentially mediate or modulate HF pathophysiology. Recently, trimethylamine N -oxide (TMAO) has emerged as a key mediator that provides a mechanistic link between gut microbiota and multiple cardiovascular diseases, including HF. Potential intervention strategies which may target this microbiota-driven pathology include dietary modification, prebiotics/probiotics, and selective binders of microbial enzymes or molecules, but further investigations into their safety and efficacy are warranted.
Current pathophysiological models of congestive heart failure unsatisfactorily explain the detrimental link between congestion and cardiorenal function. Abdominal congestion (i.e., splanchnic venous ...and interstitial congestion) manifests in a substantial number of patients with advanced congestive heart failure, yet is poorly defined. Compromised capacitance function of the splanchnic vasculature and deficient abdominal lymph flow resulting in interstitial edema might both be implied in the occurrence of increased cardiac filling pressures and renal dysfunction. Indeed, increased intra-abdominal pressure, as an extreme marker of abdominal congestion, is correlated with renal dysfunction in advanced congestive heart failure. Intriguing findings provide preliminary evidence that alterations in the liver and spleen contribute to systemic congestion in heart failure. Finally, gut-derived hormones might influence sodium homeostasis, whereas entrance of bowel toxins into the circulatory system, as a result of impaired intestinal barrier function secondary to congestion, might further depress cardiac as well as renal function. Those toxins are mainly produced by micro-organisms in the gut lumen, with presumably important alterations in advanced heart failure, especially when renal function is depressed. Therefore, in this state-of-the-art review, we explore the crosstalk between the abdomen, heart, and kidneys in congestive heart failure. This might offer new diagnostic opportunities as well as treatment strategies to achieve decongestion in heart failure, especially when abdominal congestion is present. Among those currently under investigation are paracentesis, ultrafiltration, peritoneal dialysis, oral sodium binders, vasodilator therapy, renal sympathetic denervation and agents targeting the gut microbiota.
Abstract Background Trimethylamine N -oxide (TMAO), a gut microbiota metabolite from dietary phosphatidylcholine, has mechanistic links to atherosclerotic coronary artery disease (CAD) pathogenesis ...and is associated with adverse outcomes. Objectives This study sought to examine the relationship between plasma TMAO levels and the complexity and burden of CAD and degree of subclinical myonecrosis. Methods We studied 353 consecutive stable patients with evidence of atherosclerotic CAD detected by elective coronary angiography between 2012 and 2014. Their high-sensitivity cardiac troponin T (hs-cTnT) levels were measured. SYNTAX (Synergy Between Percutaneous Coronary Intervention With Taxus and Cardiac Surgery) scores and lesion characteristics were used to quantify atherosclerotic burden. Fasting plasma TMAO was measured by mass spectrometry. Results In this prospective cohort study, the median TMAO level was 5.5 μM (interquartile range IQR: 3.4 to 9.8 μM), the median SYNTAX score was 11.0 (IQR: 4.0 to 18.5), and 289 (81.9%), 40 (11.3%), and 24 (6.8%) patients had low (0 to 22), intermediate (23 to 32), and high (≥33) SYNTAX scores, respectively. Plasma TMAO levels correlated (all p < 0.0001) with the SYNTAX score (r = 0.61), SYNTAX score II (r = 0.62), and hs-cTnT (r = 0.29). Adjusting for traditional risk factors, body mass index, medications, lesion characteristic, renal function, and high-sensitivity C-reactive protein, elevated TMAO levels remained independently associated with a higher SYNTAX score (odds ratio OR: 4.82; p < 0.0001), SYNTAX score II (OR: 1.88; p = 0.0001), but were not associated with subclinical myonecrosis (OR: 1.14; p = 0.3147). Elevated TMAO level was an independent predictor of the presence of diffuse lesions, even after adjustments for traditional risk factors and for hs-cTnT (OR: 2.05; 95% confidence interval: 1.45 to 2.90; p = 0.0001). Conclusions Fasting plasma TMAO levels are an independent predictor of a high atherosclerotic burden in patients with CAD.
Objectives To determine whether venous congestion, rather than impairment of cardiac output, is primarily associated with the development of worsening renal function (WRF) in patients with advanced ...decompensated heart failure (ADHF). Background Reduced cardiac output is traditionally believed to be the main determinant of WRF in patients with ADHF. Methods A total of 145 consecutive patients admitted with ADHF treated with intensive medical therapy guided by pulmonary artery catheter were studied. We defined WRF as an increase of serum creatinine ≥0.3 mg/dl during hospitalization. Results In the study cohort (age 57 ± 14 years, cardiac index 1.9 ± 0.6 l/min/m2 , left ventricular ejection fraction 20 ± 8%, serum creatinine 1.7 ± 0.9 mg/dl), 58 patients (40%) developed WRF. Patients who developed WRF had a greater central venous pressure (CVP) on admission (18 ± 7 mm Hg vs. 12 ± 6 mm Hg, p < 0.001) and after intensive medical therapy (11 ± 8 mm Hg vs. 8 ± 5 mm Hg, p = 0.04). The development of WRF occurred less frequently in patients who achieved a CVP <8 mm Hg (p = 0.01). Furthermore, the ability of CVP to stratify risk for development of WRF was apparent across the spectrum of systemic blood pressure, pulmonary capillary wedge pressure, cardiac index, and estimated glomerular filtration rates. Conclusions Venous congestion is the most important hemodynamic factor driving WRF in decompensated patients with advanced heart failure.
Abstract The current understanding of heart failure (HF) does not fully explain the spectrum of HF symptoms. Most HF hospitalizations are related to sodium (Na+ ) and fluid retention resulting from ...neurohumoral up-regulation. Recent insights suggest that Na+ is not distributed in the body solely as a free cation, but that it is also bound to large interstitial glycosaminoglycan (GAG) networks in different tissues, which have an important regulatory function. In HF, high Na+ intake and neurohumoral alterations disrupt GAG structure, leading to loss of the interstitial buffer capacity and disproportionate interstitial fluid accumulation. Moreover, a diminished endothelial GAG network (the endothelial glycocalyx) results in increased vascular resistance and disturbed endothelial nitric oxide production. New imaging modalities can help evaluate interstitial Na+ and endothelial glycocalyx integrity. Furthermore, several therapies have been proven to stabilize interstitial GAG networks. Hence, a better appreciation of this new Na+ “compartment” might improve current management of HF.
Background Diuretic unresponsiveness often occurs during hospital admission for acute heart failure (AHF) and is associated with adverse outcome. This study aims to investigate determinants, clinical ...outcome, and the effects of nesiritide on diuretic response early after admission for AHF. Methods Diuretic response , defined as weight loss per 40 mg of furosemide or equivalent, was examined from hospital admission to 48 hours in 4,379 patients from the ASCEND-HF trial. As an additional analysis, a urinary diuretic response metric was investigated in 5,268 patients using urine volume from hospital admission to 24 hours per 40 mg of furosemide or equivalent. Results Mean diuretic response was −0.42 kg/40 mg of furosemide (interquartile range −1.0, −0.05). Poor responders had lower blood pressure, more frequent diabetes, long-term use of loop diuretics, poorer baseline renal function, and lower urine output (all P < .01). Randomized nesiritide treatment was not associated with diuretic response ( P = .987). Good diuretic response was independently associated with a significantly decreased risk of 30-day all-cause mortality or heart failure rehospitalization (odds ratio 0.44, 95% CI 0.29-0.65, highest vs lowest quintile, P < .001). Diuretic response based on urine output per 40 mg of furosemide showed similar results in terms of clinical predictors, association with outcome, and the absence of an effect of nesiritide. Conclusions Poor diuretic response early after hospital admission for AHF is associated with low blood pressure, renal impairment, low urine output, and an increased risk of death or rehospitalization early after discharge. Nesiritide had a neutral effect on diuretic response.
Abstract Background Trimethylamine- N -oxide (TMAO) has been linked to increased cardiovascular risk. We aimed to determine the prognostic value of TMAO and its dietary precursors, choline and ...betaine, in heart failure (HF). Methods and Results In 112 patients with chronic systolic HF with comprehensive echocardiographic evaluation, we measured plasma TMAO, choline, and betaine by mass spectrometry. Median (interquartile range) TMAO levels, choline, and betaine levels were 5.8 (3.6–12.1) μmol/L, 10.9 (8.4–14.0) μmol/L, and 43.8 (37.1–53.0) μmol/L, respectively, and were correlated with each other (all P < .0001 for both). TMAO levels were significantly higher in patients with diabetes mellitus (9.4 4.9–13.2 vs 4.8 3.4–9.8 μmol/L; P = .005) and in subjects with New York Heart Association functional class III or greater (7.0 4.7–14.8 vs 4.7 3.4–11.3 μmol/L; P = .02). Elevated TMAO, choline, and betaine levels were each associated with higher plasma N-terminal pro–B-type natriuretic peptide (NT-proBNP) levels and more advanced left ventricular diastolic dysfunction, but not systolic dysfunction or inflammatory and endothelial biomarkers. Higher choline (hazard ratio HR 1.64, 95% CI 1.22–2.20; P = .001), betaine (HR 1.51, 95% CI 1.10–2.08; P = .01), and TMAO (HR 1.48, 95% CI 1.10–1.96; P = .01) predicted increased risk for 5-year adverse clinical events (death/transplantation). Only higher TMAO levels predicted incident adverse clinical events independently from age, estimated glomerular filtration rate, mitral E/septal Ea, and NT-proBNP levels (HR 1.46, 95% CI 1.03–2.14; P = .03). Conclusion Elevated plasma TMAO, choline, and betaine levels are each associated with more advanced left ventricular diastolic dysfunction and portend poorer long-term adverse clinical outcomes in chronic systolic HF. However, only higher plasma TMAO was associated with poor prognosis after adjustment for cardiorenal indices.
Abstract Background Acute decompensated heart failure (ADHF) can be complicated by electrolyte abnormalities, but the major focus has been concentrated on the clinical significance of serum sodium ...levels. Objectives This study sought to determine the prognostic significance of serum chloride levels in relation to serum sodium levels in patients with ADHF. Methods We reviewed 1,318 consecutive patients with chronic heart failure admitted for ADHF to the Cleveland Clinic between July 2008 and December 2013. We also validated our findings in an independent ADHF cohort from the University of Pennsylvania (n = 876). Results Admission serum chloride levels during hospitalization for ADHF were independently and inversely associated with long-term mortality (hazard ratio HR per unit change: 0.94; 95% confidence interval CI: 0.92 to 0.95; p < 0.001). After multivariable risk adjustment, admission chloride levels remained independently associated with mortality (HR per unit change: 0.93; 95% CI: 0.90 to 0.97; p < 0.001) in contrast to admission sodium levels, which were no longer significant (p > 0.05). Results were similar in the validation cohort in unadjusted (HR per unit change for mortality risk within 1 year: 0.93; 95% CI: 0.91 to 0.95; p < 0.001) and multivariable risk-adjusted analysis (HR per unit change for mortality risk within 1 year: 0.95; 95% CI: 0.92 to 0.99; p = 0.01). Conclusions These observations in a contemporary advanced ADHF cohort suggest that serum chloride levels at admission are independently and inversely associated with mortality. The prognostic value of serum sodium in ADHF was diminished compared with chloride.
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