Tolvaptan treatment in an adult Fontan patient with protein-losing enteropathy: a serial 23Na-MRI investigation

Background:

Protein-losing enteropathy (PLE) is a severe complication of the univentricular Fontan circulation and associated with disturbances in salt and water homeostasis. Fontan patients with PLE have a poor prognosis, with increased morbidity and mortality. Due to limited therapeutic strategies, patients are often treated only symptomatically.

Methods:

We report our first experience of Tolvaptan (TLV) treatment in a Fontan patient with PLE, severe volume retention and hyponatraemia, refractory to conventional diuretic therapy. In addition to clinical parameters, we monitored drug effects including tissue sodium and volume status via serial ²³Na-magnetic resonance imaging (²³Na-MRI) and bioimpedance spectroscopy compared with age-matched controls.

Results:

²³Na-MRI identified elevated tissue sodium, which decreased under TLV treatment, as well as volume status, while serum sodium increased and the patient’s symptoms improved. During long-term treatment, we were able to differentiate between sodium and volume status in our patient, suggesting that TLV uncoupled body sodium from water.

Conclusion:

TLV in addition to loop diuretics improved clinical symptoms of PLE and lowered tissue sodium overload. Long-term effects should be further evaluated in Fontan patients.

Blood Urea Nitrogen/Creatinine Ratio and Response to Tolvaptan in Patients with Decompensated Heart Failure: A Retrospective Analysis

INTRODUCTION

Arginine vasopressin-stimulated reabsorption of urea occurs in the collecting duct via increased expression of the urea transporter.

OBJECTIVE

The aim of this study was to evaluate whether the blood urea nitrogen/creatinine (BUN/Cr) ratio is useful for predicting tolvaptan response in patients with decompensated heart failure (HF).

METHODS

Among 71 consecutive patients with HF who received oral tolvaptan between 2010 and 2014, we retrospectively studied 33 patients with decompensated HF without any mechanical circulatory assistance or inotropic support who had already been treated with loop diuretics. A responder to tolvaptan was defined as an individual who experienced a ≥30 % increase in their respective 24-h urine volume.

RESULTS

Among the 33 patients, 21 met the criteria of a responder. The area under the receiver operating characteristic curves of BUN/Cr and BUN were 0.790 and 0.714, respectively, and the respective cut-off values for responders to tolvaptan were 23.8 and 49.0. BUN/Cr and BUN retained their significant relationships with the responder status (odds ratio for BUN/Cr >23.8: 20.9; 95 % confidence interval [CI] 2.7-531.1; p = 0.002; odds ratio for BUN ≥49: 7.7; 95 % CI 1.4-65.8; p = 0.02).

CONCLUSION

Our results suggest that high BUN/Cr may be a predictor of response to tolvaptan in decompensated HF patients. A prospective study with a large sample size is required to confirm this preliminary finding.

Hemoconcentration-guided diuresis in heart failure

One quarter of patients hospitalized for heart failure are readmitted within 30 days, perhaps related to ineffective decongestion. Limited data exist guiding the extent and duration of diuresis in patients hospitalized for heart failure. The objective of this review was to determine the prognostic value of hemoconcentration, or the relative increase in the cellular elements in blood, in patients hospitalized for heart failure and to clarify its role in guiding inpatient diuretic practices. Six post hoc retrospective studies from 2010 to 2013 were available for review. Hemoconcentration was consistently associated with markers of aggressive fluid removal, including higher diuretic dosing and reduced body weight, but increased risk of in-hospital worsening renal function. Despite this, hemoconcentration was associated with improved short-term mortality and rehospitalization. Hemoconcentration is a practical, readily available, noninvasive, economically feasible strategy to help guide diuresis and monitor congestion relief in patients hospitalized for worsening heart failure. Clinicians should strongly consider using changes in hemoglobin and hematocrit as an adjunct to other available measures of decongestion and clinical acumen in inpatient heart failure care.

Association of arginine vasopressin levels with outcomes and the effect of V2 blockade in patients hospitalized for heart failure with reduced ejection fraction: insights from the EVEREST trial

BACKGROUND

Arginine vasopressin (AVP) levels are elevated in proportion to heart failure severity and are associated with higher cardiovascular mortality in ambulatory patients. However, the relationship between baseline and trends in AVP with outcomes in patients hospitalized for worsening heart failure with reduced ejection fraction is unclear.

METHODS AND RESULTS

The Efficacy of Vasopressin Antagonism in Heart Failure Outcome Study with Tolvaptan (EVEREST) trial investigated the effects of tolvaptan in patients with worsening heart failure and ejection fraction ≤40%. The present analysis examined baseline and follow-up AVP levels in 3196 EVEREST patients with valid AVP measurements. Coprimary end points included all-cause mortality, and the composite of cardiovascular mortality or heart failure hospitalization. Median follow-up was 9.9 months. Times to events were compared with univariate log-rank tests and multivariable Cox regression models, adjusted for baseline risk factors. After adjusting for baseline covariates, elevated AVP levels were associated with increased all-cause mortality (hazard ratio, 1.33; 95% confidence interval, 1.13-1.55) and cardiovascular mortality or heart failure hospitalization (hazard ratio, 1.23; 95% confidence interval, 1.08-1.39). There was no interaction of baseline AVP with treatment assignment in terms of survival (P=0.515). Tolvaptan therapy increased the proportion of patients with elevated AVP (P<0.001), but this had no effect on mortality (hazard ratio, 0.95; 95% confidence interval, 0.72-1.24).

CONCLUSIONS

Elevated baseline AVP level was independently predictive of mortality, but did not identify a group of patients who had improved outcomes with tolvaptan treatment. Tolvaptan treatment increased AVP levels during follow-up, but this incremental increase was not associated with worsened outcomes.