Thiamin cardiac failure

Cardiovascular system symptoms—If the thiamin deficiency persists, the heart muscles weaken and heart failure may result Also, the smooth muscles of the vascular system may be involved, causing peripheral vasodilation. As a result of cardiac failure, peripheral ema may be observed in the extremities. 

Severe multisystem trauma, endotoxemia, or situations in which there is a raised metabolic demand for thiamin, such as pregnancy, thyrotoxicosis, and intercurrent illness or impaired absorption (e.g., alcohol abuse or gastrointestinal disease or resection), can produce subclinical evidence of thiamin deficiency or more severe life-threatening aspects of beriberi, such as renal and/or cardiovascular failure. The elderly may be particularly at risk of subclinical thiamin deficiency. One Belgian study on patients with a mean age of 83 years reported that 40% had a raised TDP effect (>15%), in whom there was a high proportion of Alzheimer s disease, depression, cardiac failure, and falls. The diuretic furosemide was also more frequently taken by the thiamin-deficient patients. 

Thiamin that is not bound to plasma proteins is rapidly filtered at the glomerulus. Diuresis increases the excretion of the vitamin, and patients who are treated with diuretics are potentially at risk of thiamin deficiency. Some of the diuretics used in the treatment of hypertension may also inhibit cardiac (and other tissue) uptake of thiamin, thus further impairing thiamin status, which may be a factor in the etiology of heart failure (Suter and Vetter, 2000). 

Thiamine, also known as vitamin B, is fairly ubiquitous. Thiamine deficiency is uncommon except in alcoholics as a result of nutritional deficiencies and malabsorption. The classic clinical triad of dementia, ataxia (difficulty with walking), and eye findings may be seen, but more commonly, only forgetfulness is noted. Sometimes, thiamine deficiency can lead to vague symptoms such as leg numbness or tingling. Because thiamine is water soluble, it can be added to intravenous fluids and administered in that way. Other manifestations include beri beri, which is cardiac involvement leading to a high cardiac output, and vasodilation. Affected patients often feel warm and flushed, and they can have heart failure. 

Al Martini. A1 Martini presents a second time with an alcohol-related J high output form of heart failure sometimes referred to as wet beriberi, or as the beriberi heart (see Chapter 9). The term wet refers to the fluid retention which may eventually occur when left ventricular contractility is so compromised that cardiac output, although initially relatively high, cannot meet the demands of the peripheral vascular beds, which have dilated in response to the thiamine deficiency. 

Symptoms of overt beriberi are usually abrupt with presentation of left ventricular cardiac and peripheral vascular failure yielding water retention due to stimulation of the renin-angiotensin-aldosterone axis by hypovolemia, as well as striated and smooth muscles weakness in the wet form of the disease. At this stage of the disease, the clinical diagnosis is usually apparent but outcome of the supplementary treatment with thiamine may be poor, due to irreversible alterations in muscles and the central nervous system (CNS). 

The prevalence of subclinical forms of thiamine deficiency is relatively frequent in several risk groups including alcoholics, elderly, cardiac and renal failure patients, and infants. 

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