Association of weight change with subsequent outcomes in patients hospitalized with acute decompensated heart failure

Weight change in heart failure inpatients not associated with 30-day readmission

Background: The association of weight change and short-term readmission in patients hospitalized for heart failure (HF) has not been well studied. Methods: We collected clinical and weight data from patients admitted with decompensated HF to a single center (2012-2013). We performed logistic regression to determine the association between weight change and two outcomes: a total of 30-day HF-specific readmission and 30-day all-cause readmission. Results: Admission and discharge weights were documented in 479/658 patients (73%). Weight loss >2 kg was not associated with 30-day all-cause or HF-specific readmission when compared with more modest inpatient weight change (-2 kg to +2 kg; all-cause readmission odds ratio: 0.86; CI: 0.56-1.37; HF-specific readmission odds ratio: 1.15; CI: 0.61-2.16). Conclusion: Among HF inpatients, in-hospital weight loss was not associated with 30-day all-cause or HF-specific readmission.

Relation of Volume Overload to Clinical Outcomes in Acute Heart Failure (From ASCEND-HF)

We aimed to study whether jugular venous distension (JVD) and peripheral edema were associated with worse outcomes in patients with acute heart failure in the Acute Study of Clinical Effectiveness of Nesiritide in Decompensated Heart Failure trial. Of 7,141 patients in Acute Study of Clinical Effectiveness of Nesiritide in Decompensated Heart Failure, 7,135 had complete data on baseline JVD and peripheral edema status. Patients were grouped according to baseline examination findings: (1) no JVD or peripheral edema; (2) JVD only; (3) peripheral edema only; (4) JVD and peripheral edema. We used unadjusted and adjusted logistic or Cox regression analyses to assess associations between groups and the outcomes of index length of stay (LOS), in-hospital mortality, 30- and 180-day all-cause mortality. Patients with peripheral edema (Groups 3 and 4) had higher body mass index, NT-proBNP and BNP values, and more co-morbid disease, and reduced left ventricular ejection fraction compared with patients in Groups 1-2. The median (25th-75th) LOS for Groups 1-4 was 6 (4-9), 5 (4-8), 7 (4-11), and 6 days (4-10), respectively. For the 30-day and 180-day outcomes, adjusted analyses found no significant difference in risk for patients presenting with JVD only or peripheral edema only as compared with patients without evidence of JVD or peripheral edema (p >0.05 for all). The presence of both JVD and peripheral edema was associated with an adjusted 24% increase in risk for all-cause mortality at 30 days, but no risk difference at 180 days. In conclusion, in patients with heart failure presenting to the hospital with dyspnea, the presence of peripheral edema is associated with a longer hospital LOS, but no difference in short- and long-term clinical outcomes when compared with patients wihout peripheral edema. The combination of peripheral edema and JVD identifies the highest risk cohort for poor clinical outcomes.

Analysis of Consistency of Transthoracic Bioimpedance Measurements Acquired with Dry Carbon Black PDMS Electrodes, Adhesive Electrodes, and Wet Textile Electrodes

The detection of intrathoracic volume retention could be crucial to the early detection of decompensated heart failure (HF). Transthoracic Bioimpedance (TBI) measurement is an indirect, promising approach to assessing intrathoracic fluid volume. Gel-based adhesive electrodes can produce skin irritation, as the patient needs to place them daily in the same spots. Textile electrodes can reduce skin irritation; however, they inconveniently require wetting before each use and provide poor adherence to the skin. Previously, we developed waterproof reusable dry carbon black polydimethylsiloxane (CB/PDMS) electrodes that exhibited a good response to motion artifacts. We examined whether these CB/PDMS electrodes were suitable sensing components to be embedded into a monitoring vest for measuring TBI and the electrocardiogram (ECG). We recruited N = 20 subjects to collect TBI and ECG data. The TBI parameters were different between the various types of electrodes. Inter-subject variability for copper-mesh CB/PDMS electrodes and Ag/AgCl electrodes was lower compared to textile electrodes, and the intra-subject variability was similar between the copper-mesh CB/PDMS and Ag/AgCl. We concluded that the copper mesh CB/PDMS (CM/CB/PDMS) electrodes are a suitable alternative for textile electrodes for TBI measurements, but with the benefit of better skin adherence and without the requirement of wetting the electrodes, which can often be forgotten by the stressed HF subjects.

Organ dysfunction, injury and failure in acute heart failure: from pathophysiology to diagnosis and management. A review on behalf of the Acute Heart Failure Committee of the Heart Failure Association (HFA) of the European Society of Cardiology (ESC)

Organ injury and impairment are commonly observed in patients with acute heart failure (AHF), and congestion is an essential pathophysiological mechanism of impaired organ function. Congestion is the predominant clinical profile in most patients with AHF; a smaller proportion presents with peripheral hypoperfusion or cardiogenic shock. Hypoperfusion further deteriorates organ function. The injury and dysfunction of target organs (i.e. heart, lungs, kidneys, liver, intestine, brain) in the setting of AHF are associated with increased risk for mortality. Improvement in organ function after decongestive therapies has been associated with a lower risk for post-discharge mortality. Thus, the prevention and correction of organ dysfunction represent a therapeutic target of interest in AHF and should be evaluated in clinical trials. Treatment strategies that specifically prevent, reduce or reverse organ dysfunction remain to be identified and evaluated to determine if such interventions impact mortality, morbidity and patient-centred outcomes. This paper reflects current understanding among experts of the presentation and management of organ impairment in AHF and suggests priorities for future research to advance the field.

Intracardiac Pressures Measured Using an Implantable Hemodynamic Monitor: Relationship to Mortality in Patients With Chronic Heart Failure

BACKGROUND

The purpose of this analysis was to examine whether implantable hemodynamic monitor-derived baseline estimated pulmonary artery diastolic pressure (ePAD) and change from baseline ePAD were independent predictors of all-cause mortality in patients with chronic heart failure.

METHODS AND RESULTS

Retrospective analysis used data from 3 studies (n=790 patients; 216 deaths). Baseline ePAD was related to mortality using a multivariable model including baseline and demographic data. Changes in ePAD defined as change from baseline to 6 months and from baseline to 14 days before death or exit from study were related to subsequent mortality, and analysis was adjusted for baseline ePAD. Area under the pressure versus time curve during 180 days before death or exit from study was related to mortality. Baseline ePAD, independent of other covariates, was a significant predictor of mortality (hazard ratio=1.07; 95% confidence interval=1.05-1.09; P<0.0001). Change in ePAD was an independent predictor of mortality (hazard ratio=1.07; 95% confidence interval=1.05-1.100; P=0.0008). Increased ePAD of 3, 4, or 5 mm Hg from baseline to 6 months was associated with increased mortality risk of 23.8%, 32.9%, or 42.8%. Change in ePAD from baseline to 14 days before death or exit from study was higher in patients who died (3.0±8 versus 1.7±10 mm Hg; P=0.003). Area under the pressure versus time curve in the final 180 days before death or exit from study was higher in patients who died versus those alive at end of study (185±668 versus 17±482 mm Hg.days; P=0.006).

CONCLUSIONS

Implantable hemodynamic monitor-derived baseline ePAD and change from baseline ePAD were independent predictors of mortality in chronic heart failure patients.

Rapid and Highly Accurate Prediction of Poor Loop Diuretic Natriuretic Response in Patients With Heart Failure

BACKGROUND

Removal of excess sodium and fluid is a primary therapeutic objective in acute decompensated heart failure and commonly monitored with fluid balance and weight loss. However, these parameters are frequently inaccurate or not collected and require a delay of several hours after diuretic administration before they are available. Accessible tools for rapid and accurate prediction of diuretic response are needed.

METHODS AND RESULTS

Based on well-established renal physiological principles, an equation was derived to predict net sodium output using a spot urine sample obtained 1 or 2 hours after loop diuretic administration. This equation was then prospectively validated in 50 acute decompensated heart failure patients using meticulously obtained timed 6-hour urine collections to quantify loop diuretic-induced cumulative sodium output. Poor natriuretic response was defined as a cumulative sodium output of <50 mmol, a threshold that would result in a positive sodium balance with twice-daily diuretic dosing. Following a median dose of 3 mg (2-4 mg) of intravenous bumetanide, 40% of the population had a poor natriuretic response. The correlation between measured and predicted sodium output was excellent (r=0.91; P<0.0001). Poor natriuretic response could be accurately predicted with the sodium prediction equation (area under the curve =0.95, 95% confidence interval 0.89-1.0; P<0.0001). Clinically recorded net fluid output had a weaker correlation (r=0.66; P<0.001) and lesser ability to predict poor natriuretic response (area under the curve =0.76, 95% confidence interval 0.63-0.89; P=0.002).

CONCLUSIONS

In patients being treated for acute decompensated heart failure, poor natriuretic response can be predicted soon after diuretic administration with excellent accuracy using a spot urine sample.

Markers of decongestion, dyspnea relief, and clinical outcomes among patients hospitalized with acute heart failure

BACKGROUND

Congestion is a primary driver of symptoms in patients with acute heart failure, and relief of congestion is a critical goal of therapy. Monitoring of response to therapy through the assessment of daily weights and net fluid loss is the current standard of care, yet the relationship between commonly used markers of decongestion and both patient reported symptom relief and clinical outcomes are unknown.

METHODS AND RESULTS

We performed a retrospective analysis of the randomized clinical trial, diuretic optimization strategy evaluation in acute heart failure (DOSE-AHF), enrolling patients hospitalized with a diagnosis of acute decompensated heart failure. We assessed the relationship among 3 markers of decongestion at 72 hours-weight loss, net fluid loss, and percent reduction in serum N terminal B-type natriuretic peptide (NT-proBNP) level-and relief of symptoms as defined by the dyspnea visual analog scale area under the curve. We also determined the relationship between each marker of decongestion and 60-day clinical outcomes defined as time to death, first rehospitalization or emergency department visit. Mean age was 66 years, mean ejection fraction was 35%, and 27% had ejection fraction ≥50%. Of the 3 measures of decongestion assessed, only percent reduction in NT-proBNP was significantly associated with symptom relief (r=0.13; P=0.04). There was no correlation between either weight loss or net fluid loss and symptom relief, (r=0.04; P=0.54 and r=0.07; P=0.27, respectively). Favorable changes in each of the 3 markers of decongestion were associated with improvement in time to death, rehospitalization, or emergency department visit at 60 days (weight: hazard ratio, 0.91; 95% confidence interval, 0.85-0.97 per 4 lbs; weight lost; fluid hazard ratio, 0.94; 95% confidence interval, 0.90-0.99 per 1000 mL fluid loss; NT-proBNP hazard ratio, 0.95; 95% confidence interval, 0.91-0.99 per 10% reduction). These associations were unchanged after multivariable adjustment with the exception that percent reduction in NT-proBNP was no longer a significant predictor (hazard ratio, 0.97; 95% confidence interval, 0.93-1.02). The rates of death, HF hospitalization, or emergency department visit at 60 days for patients with 0, 1, 2, and 3 markers of decongestion (above the median) were 67%, 64%, 46%, and 38%, respectively (log rank P value=0.05).

CONCLUSIONS

Weight loss, fluid loss, and NT-proBNP reduction at 72 hours are poorly correlated with dyspnea relief. However, favorable improvements in each of the 3 markers were associated with improved clinical outcomes at 60 days. These data suggest the need for ongoing research to understand the relationships among symptom relief, congestion, and outcomes in patients with acute decompensated heart failure.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. UNIQUE IDENTIFIER: NCT00577135.

Effect of admission oral diuretic dose on response to continuous versus bolus intravenous diuretics in acute heart failure: an analysis from diuretic optimization strategies in acute heart failure

BACKGROUND

Results from the DOSE-AHF study suggest that an initial continuous infusion of loop diuretics is not superior to bolus dosing with regard to clinical endpoints in acute heart failure. We hypothesized that outpatient furosemide dose was associated with congestion and poorer renal function and explored the hypothesis that a continuous infusion may be more effective in patients on higher outpatient diuretic doses.

METHODS

The DOSE-AHF study randomized 308 patients within 24 hours of admission to high versus low initial intravenous diuretic dose given as either a continuous infusion or bolus. We compared baseline characteristics and assessed associations between mode of administration (bolus vs continuous) and outcomes in patients receiving high-dose (≥120 mg furosemide equivalent, n = 177) versus low-dose (<120 mg furosemide equivalent, n = 131) outpatient diuretics.

RESULTS

Patients on higher doses of furosemide were less frequently on renin-angiotensin system inhibitors (P = .01) and had worse renal function and more advanced symptoms. There was a significant interaction between outpatient dose and mode of therapy (P = .01) with respect to net fluid loss at 72 hours after adjusting for creatinine and intensification strategy. Admission diuretic dose was associated with an increased risk of death or rehospitalization at 60 days (adjusted hazard ratio 1.08 per 20-mg increment in dose, 95% CI 1.01-1.16, P = .03).

CONCLUSIONS

In acute heart failure, patients on higher diuretic doses have greater disease severity and may benefit from an initial bolus strategy.

Fluid management strategies in heart failure

In patients with chronic heart failure, fluid retention (or hypervolemia) is often the stimulus for acute decompensated heart failure that requires hospitalization. The pathophysiology of fluid retention is complex and involves both hemodynamic and clinical congestion. Signs and symptoms of both hemodynamic and clinical congestion should be assessed serially during hospitalization. Core heart failure drug and cardiac device therapies should be provided, and ultrafiltration may be warranted. Critical care, intermediate care, and telemetry nurses have roles in both assessment and management of patients hospitalized with acute decompensated heart failure and fluid retention. Nurse administrators and managers have heightened their attention to fluid retention because the Medicare performance measure known as the risk-standardized 30-day all-cause readmission rate after heart failure hospitalization can be attenuated by fluid management strategies initiated by nurses during a patient's hospitalization.

Comparing measurement error correction methods for rate-of-change exposure variables in survival analysis

In this article we focus on comparing measurement error correction methods for rate-of-change exposure variables in survival analysis, when longitudinal data are observed prior to the follow-up time. Motivational examples include the analysis of the association between changes in cardiovascular risk factors and subsequent onset of coronary events. We derive a measurement error model for the rate of change, estimated through subject-specific linear regression, assuming an additive measurement error model for the time-specific measurements. The rate of change is then included as a time-invariant variable in a Cox proportional hazards model, adjusting for the first time-specific measurement (baseline) and an error-free covariate. In a simulation study, we compared bias, standard deviation and mean squared error (MSE) for the regression calibration (RC) and the simulation-extrapolation (SIMEX) estimators. Our findings indicate that when the amount of measurement error is substantial, RC should be the preferred method, since it has smaller MSE for estimating the coefficients of the rate of change and of the variable measured without error. However, when the amount of measurement error is small, the choice of the method should take into account the event rate in the population and the effect size to be estimated. An application to an observational study, as well as examples of published studies where our model could have been applied, are also provided.

Chronic heart failure: contemporary diagnosis and management

Chronic heart failure (CHF) remains the only cardiovascular disease with an increasing hospitalization burden and an ongoing drain on health care expenditures. The prevalence of CHF increases with advancing life span, with diastolic heart failure predominating in the elderly population. Primary prevention of coronary artery disease and risk factor management via aggressive blood pressure control are central in preventing new occurrences of left ventricular dysfunction. Optimal therapy for CHF involves identification and correction of potentially reversible precipitants, target-dose titration of medical therapy, and management of hospitalizations for decompensation. The etiological phenotype, absolute decrease in left ventricular ejection fraction and a widening of QRS duration on electrocardiography, is commonly used to identify patients at increased risk of progression of heart failure and sudden death who may benefit from prophylactic implantable cardioverter-defibrillator placement with or without cardiac resynchronization therapy. Patients who transition to advanced stages of disease despite optimal traditional medical and device therapy may be candidates for hemodynamically directed approaches such as a left ventricular assist device; in selected cases, listing for cardiac transplant may be warranted.