Are non-invasive estimations of plasma volume an accurate measure of congestion in patients with chronic heart failure?

AIMS: We report associations between different formulae for estimating plasma volume status (PVS) and clinical and ultrasound markers of congestion in patients with chronic heart failure (CHF) enrolled in the Hull Lifelab registry. METHODS AND RESULTS: Cohort 1 comprised patients with data on signs and symptoms at initial evaluation (n = 3505). Cohort 2 included patients with ultrasound assessment of congestion [lung B-line count, inferior vena cava (IVC) diameter, jugular vein distensibility (JVD) ratio] (N = 341). Two formulae for PVS were used: (a) Hakim (HPVS) and (b) Duarte (DPVS). Results were compared with clinical and ultrasound markers of congestion. Outcomes assessed were mortality and the composite of heart failure (HF) hospitalisation and all-cause mortality. In cohort 1, HPVS was associated with mortality [hazard ratio (HR) per unitary increase = 1.02 (1.01-1.03); P < 0.001]. In cohort 2, HPVS was associated with B-line count (HR) = 1.05 [95% confidence interval (CI) (1.01-1.08); P = 0.02] and DPVS with the composite outcome [HR = 1.26 (1.01-1.58); P = 0.04]. HPVS and DPVS were strongly related to haemoglobin concentration and HPVS to weight. After multivariable analysis, there were no strong or consistent associations between PVS and measures of congestion, severity of symptoms, or outcome. By contrast, log[NTproBNP] was strongly associated with all three. CONCLUSION: Amongst patients with CHF, HPVS and DPVS are not strongly or consistently associated with clinical or ultrasound evidence of congestion, nor clinical outcomes after multivariable adjustment. They appear only to be surrogates of the variables from which they are calculated with no intrinsic clinical utility.

Re-defining iron deficiency in patients with heart failure.

INTRODUCTION: Iron deficiency (ID) is common in patients with chronic heart failure (CHF) and is associated with worse symptoms and prognosis regardless of whether anemia is also present. However, randomized controlled trials (RCT) of intravenous (IV) iron in patients with CHF have produced inconsistent results. This review considers the past, present, and future of defining and treating ID in patients with CHF. AREAS COVERED: The current guideline definition of ID is a serum ferritin <100 µg/L or serum ferritin 100-299 µg/L and transferrin saturation (TSAT) <20% derived from trials of IV iron in patients with end-stage renal failure. Ferritin synthesis and secretion is promoted by inflammatory cytokines which are raised in patients with CHF; thus, using ferritin to define iron deficiency in patients with CHF may be flawed. Observational data suggest that the current definition of iron deficiency in CHF does not identify a high-risk population. EXPERT OPINION: Alternative indicators of ID such as low serum iron concentrations or TSAT may better identify patients with ID who are at greater risk of adverse outcome and thus, possibly, more likely to benefit from IV iron.

Hypochloraemia following admission to hospital with heart failure is common and associated with an increased risk of readmission or death: a report from OPERA-HF.

AIMS: Hypochloraemia is common in patients hospitalized with heart failure (HF) and associated with a high risk of adverse outcomes during admission and following discharge. We assessed the significance of changes in serum chloride concentrations in relation to serum sodium and bicarbonate concentrations during admission in a cohort of 1002 consecutive patients admitted with HF and enrolled into an observational study based at a single tertiary centre in the UK. METHODS AND RESULTS: Hypochloraemia (<96 mmol/L), hyponatraemia (<135 mmol/L), and metabolic alkalosis (bicarbonate >32 mmol/L) were defined by local laboratory reference ranges. Outcomes assessed were all-cause mortality, all-cause mortality or all-cause readmission, and all-cause mortality or HF readmission. Cox regression and Kaplan-Meier curves were used to investigate associations with outcome. During a median follow-up of 856 days (interquartile range 272-1416), discharge hypochloraemia, regardless of serum sodium, or bicarbonate levels was associated with greater all-cause mortality [hazard ratio (HR) 1.44, 95% confidence interval (CI) 1.15-1.79; P = 0.001], all-cause mortality or all-cause readmission (HR 1.26, 95% CI 1.04-1.53; P = 0.02), and all-cause mortality or HF readmission (HR 1.41, 95% CI 1.14-1.74; P = 0.002) after multivariable adjustment. Patients with concurrent hypochloraemia and natraemia had lower haemoglobin and haematocrit, suggesting congestion; those with hypochloraemia and normal sodium levels had more metabolic alkalosis, suggesting decongestion. CONCLUSION: Hypochloraemia is common at discharge after a hospitalization for HF and is associated with worse outcome subsequently. It is an easily measured clinical variables that is associated with morbidity or mortality of any cause.