Abraham_edit.qxp 29/7/08 10:19 Page 57
Heart Failure
Managing Hyponatremia in Heart Failure
a report by
William T Abraham, MD, FACP, FAAC
Professor of Internal Medicine, and Chief, Division of Cardiovascular Medicine, Ohio State University College of Medicine, and
Deputy Director, Dorothy M Davis Heart and Lung Research Institute
Hyponatremia is the most common electrolytic abnormality in clinical practice direct stimulation of myocardial hypertrophy. CHF causes a decrease in cardiac
and has a reported incidence of 15–30% in adults.
1,2
It is particularly common output and circulating blood volume, which in turn triggers a compensatory
in heart failure: the Organized Program to Initiate Life Saving Treatment in response aimed at preserving blood pressure. This stimulates the body to retain
Patients Hospitalized for Heart Failure (OPTIMIZE-HF) registry recorded that both water and sodium.
11,12
In addition, in CHF sympathetic stimulation is
25.3% of 47,647 heart failure patients had hyponatremia on admission.
3
In increased, causing renal vasoconstriction.
13
The group most at risk for
this registry, patients with hyponatremia had increased in-hospital and post- hyponatremia in heart failure is female geriatrics with low body mass.
11
discharge mortality and longer median hospital stay compared with those with
higher sodium levels. Few studies have evaluated the treatment of There is evidence that heart failure patients are more sensitive to low serum
hyponatremia in heart failure. Currently, there are no guidelines for the sodium levels than the general population. One study found a significant
appropriate way to deal with low serum sodium levels in heart failure patients; association between in-hospital mortality in heart failure patients and sodium
treatment generally consists of fluid restriction, which has not been clinically levels of 135–138mmol/l,
3
while another study found that a mean serum
examined in this setting. Vasopressin receptor antagonists that selectively sodium concentration of 138mmol/l or less was a predictor for mortality due
increase solute-free water excretion by the kidneys are showing evidence of to pump failure in patients with mild to moderate heart failure.
14
Therefore, it
being effective for the treatment of hyponatremia in heart failure. This paper has been suggested that the definition of hyponatremia for patients with heart
will discuss current and future treatments for the management of failure should be altered to a serum sodium level of 138mmol/l or lower.
hyponatremia in heart failure.
The prognostic value of hyponatremia regarding mortality in patients with
Classification of Hyponatremia heart failure was examined in the Evaluation Study of Congestive Heart
The definition of hyponatremia is serum sodium concentration <135mmol/l. Failure and Pulmonary Artery Catheterization Effectiveness (ESCAPE).
15
Hyponatremia can be caused by either an excessive loss of sodium, known Approximately one-quarter of patients were found to have hypervolemic
as depletional hyponatremia, or excessive retention of water, called hyponatremia on admission.
16
The ESCAPE trial continued for 180 days and
dilutional hyponatremia.
4,5
Depletional hyponatremia is caused by certain concluded that persistent hyponatremia is an independent predictor of
disorders or drugs that produce a decrease in extracellular fluid, leading to mortality, heart failure hospitalization, and death. Persistent hyponatremia
an excessive loss of renal salts. Dilutional hyponatremia has two primary was also associated with higher rates of heart failure re-hospitalization and
classifications: normal extracellular volume (euvolemic) or elevated
extracellular volume (hypervolemic). Euvolemic hyponatremia is defined by
William T Abraham, MD, FACP, FACC, is a Professor of Internal
a serum osmolarity of <270mosm/l and a urine osmolarity of 100mosm/l. It
Medicine and Chief of the Division of Cardiovascular Medicine
is most commonly a syndrome of inappropriate antidiuretic hormone at the Ohio State University College of Medicine. He also serves
(SIADH) and is associated with elevated arginine vasopressin (AVP) release.
as Deputy Director of the Dorothy M Davis Heart and Lung
Research Institute. He previously held faculty appointments at
Hypervolemic hyponatremia is generally the result of fluid overload
the University of Colorado, the University of Cincinnati, and the
associated with raised AVP secretion, advanced liver cirrhosis, renal disease, University of Kentucky. Dr Abraham’s research interests include
or congestive heart failure.
6
In these instances total body sodium is elevated
the role of the kidney in heart failure, neurohormonal
mechanisms in heart failure, sleep-disordered breathing in heart
but total body water is increased disproportionately, causing hyponatremia
failure, and clinical drug and device trials in heart failure and cardiac transplantation. He has
and edema. Severe hyponatremia can lead to water movement away from received grants from the National Institutes of Health (NIH), the American College of Cardiology
the brain, causing cerebral edema and, possibly, intracranial hemorrhage.
(ACC), and the Aetna Quality Care Foundation, and has participated as Principal Investigator in
more than 100 multicenter clinical drug and device trials. In addition to authoring more than 600
original papers, abstracts, book chapters, and review articles, Dr Abraham has co-edited a leading
Hyponatremia in Heart Failure textbook on heart failure entitled Heart Failure: A Practical Approach to Treatment. He serves on
Chronic heart failure (CHF) patients often display signs and symptoms of
the Editorial Boards of several major journals, including Congestive Heart Failure and Journal
Watch Cardiology. He is also a scientific reviewer for such publications as Circulation, the European
increased AVP secretion, and both heart failure and hyponatremia patients
Heart Journal, and the Journal of the American College of Cardiology. Dr Abraham has been
have elevated levels of circulating neurohormones—such as angiotensin II, recognized as one of the ‘Best Doctors in America’ for six consecutive years. He received his MD
renin, cathecholamines, and vasopressin—compared with patients with normal
from Harvard Medical School, before completing a residency in internal medicine and fellowships
in cardiology and heart failure/cardiac transplantation at the University of Colorado Health
sodium levels.
6–8
The release of AVP primarily causes water retention in the renal
Sciences Center. He is board-certified in internal medicine and cardiovascular diseases.
collecting duct.
9,10
However, theoretically an increase in AVP secretion could add
to heart failure through aggravating systolic and diastolic wall stress and by
© TOUCH BRIEFINGS 2008
57
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78 |
Page 79 |
Page 80 |
Page 81 |
Page 82 |
Page 83 |
Page 84