The prognostic significance of serum sodium in a population undergoing cardiac resynchronisation therapy

Abstract

PurposeTo determine the prognostic implications of changes towards hyponatremia at varying time-points in the treatment of patients undergoing cardiac resynchronisation therapy (CRT).MethodsA retrospective series of 249 patients was studied from 2002 to 2013. The population was categorized on the basis of serum sodium profile at baseline, at 1 month and at 6 month follow up visits following successful CRT implantation. The composite endpoint was all-cause mortality and heart failure hospitalisation (defined by the need for intravenous diuretic therapy) following CRT implantation.ResultsA total of 249 patients (67.8 ± 12.5 years; NYHA class III/IV 75; LVEF 27.2 ± 8.8%) were followed up for a median of 5.5 years. Hyponatremia at baseline, 1 month or 6 months follow up did not predict the composite endpoint. 26% of patients showed hyponatremia at baseline prior to CRT implantation, while it was present in 19.9% of patients 1 month (p = 0.003) and in 16% (p < 0.001) 6 months after CRT implantation. There was a significantly worse outcome for those patients who developed hyponatremia 6 months after CRT implantation. In multivariate analysis, the intake of loop diuretics (HR 1.76 [1.04–2.95], p = 0.03) and renal impairment (urea > 7.0 mmol/l) (HR 1.61 [1.05–2.46], p = 0.03) at baseline were associated with an increased risk of unplanned heart failure hospitalisation and all-cause mortality after CRT implantation.ConclusionsA change towards hyponatremia when observed 6 months after CRT implantation may predict a worse clinical outcome. Additionally, renal impairment and higher diuretic doses are associated with an increased risk of mortality in the population analysed.

The osmotic demyelination syndrome: the resilience of thalamic neurons is verified with transmission electron microscopy

“…29 In the old and current literature, number of reports of regional CPM and EPM ODS defects showed as consequences of abrupt adjustment of a temporary or chronic deficiency of the homeostatic sodium gradient. Its etiology can be found in a series of diverse afflictions, 30 such as in these exemplary list of clinical studies: alcoholism and/or combined with malnutrition, 1,19,[31][32][33][34][35][36][37][38][39][40] craniofacial and neurosurgeries, 41,42 diarrhea with AIDS, 43 excessive vomitus alone 44 or associated with pregnancy, 45,46 hyper glycemia, 47 pediatric diabetes, 48 diabetes insipidus due to cancer treatments, 49 folate deficiency, and kidney defect, 50 Grave's disease, 51 diuretic unbalance, and heart failure, [52][53][54][55] heat exhausting exercise, 56,57 liver cirrhosis, 58,59 or liver transplantation. 29,60,61 Disorders of sodium and osmotic homeostasis have been found in diverse small mammals.…”

Predictors of one-year mortality in ambulatory patients with advanced heart failure awaiting heart transplantation

“…A low cardiac output secondary to a reduced left ventricular systolic function causes the activation of several neurohormonal systems to maintain blood volume and pressure [39]. In turn, neurohormonal activation, involving the activation of reninangiotensin-aldosterone system (RAAS), arginine vasopressin release, and up-regulation of sympathetic nervous activity, results in decreased water and sodium delivery to the kidneys, decreased water excretion, water retention by the kidneys, and, ultimately, hyponatremia [40].…”

“…There is a strong correlation between serum sodium and plasma neurohormone concentrations, such as norepinephrine, renin, and angiotensin II, which are powerful promoters of cardiac myocyte hypertrophy and necrosis, and are linked to a poor outcome in HF patients [40][41][42]. In this context, a lower level of serum sodium may be a marker of neurohormonal activation, reflecting the severity of HF [43].…”

Thalamic Neuron Resilience during Osmotic Demyelination Syndrome (ODS) Is Revealed by Primary Cilium Outgrowth and ADP-ribosylation factor-like protein 13B Labeling in Axon Initial Segment

“…In other cases, deafness, memory loss to seizure, unresponsiveness and eventually coma have occurred, e.g., [21,28,50,124]. Additional case examples of ODS can be found in patients affected by other clinical situations where sodium out-of-balance events were associated with or resulted in kidney function disorders [45][46][47][88][89][90]97,[125][126][127], hepatic disorders [91,128] and transplantation [128][129][130][131], thyroid Grave's disease and diabetes [132,133], cardiology care, e.g., [134][135][136][137][138][139], drug interactions [140], and in those patients with autoimmune infections [141]. Finally, specific heat-exhausting exercises where dehydration could create prolonged sodium imbalance and hyponatremia [142][143][144][145][146][147][148][149][150][151][152].…”