A new study from Italy reports that a supplementation with vitamin D may increase the ejection fraction of the heart in patients with severe heart failure and insufficient vitamin D levels.
The randomized controlled trial measured the ejection fraction of the heart and blood vitamin D concent- rations of 23 patients, mean age of 74 years, with severe heart failure and low vitamin D levels (below
30 ng/mL) who received 4000 IU vitamin D3 daily or placebo for six months (1). The study results show-
ed that participants who were treated with vitamin D had a significantly increased vitamin D level (from
16.2 ng/ml at the beginning of the study to 31.7 ng/ml after six months) and ejection fraction, compared
to the placebo group.
The researchers commented that the supplementation was capable of achieving the normal range of plasma vitamin D level (30 ng/mL), as established by the WHO (2). The Endocrine Society guidelines suggest a maintenance dose of 1500–2000 IU vitamin D daily to maintain a serum level concentration above 30 ng/mL (3). In addition, the study results confirm experimental data showing that the correction of vitamin D defi- ciency is able to reduce heart ventricle enlargement (hypertrophy) and most likely attenuates hypertension (4). Earlier clinical trials with patients with heart failure and infants with chronic congestive heart failure al- ready reported a significant improvement in heart functions such as ejection fraction after vitamin D supple- mentation (5, 6). According to the scientists, the main potential mechanism that could explain a direct pro- tective effect of vitamin D in heart failure includes effects on myocardial contractile function, regulation of blood pressure, heart remodeling and reduced left ventricular hypertrophy.
Heart failure is characterized by the inability of the heart to pump blood effectively to all areas throughout the body. Ejection fraction, a measurement of how much blood the heart pumps out with each beat, is, therefore, an important parameter in recognizing and diagnosing heart failure. An EF of less than 40% is considered evidence of heart failure while a normal EF is considered in the range of 55% to 70%.