What does iron do in the heart?

Our hearts could not function without iron. This mineral is needed to make hemoglobin, which delivers oxygen to the body, and myoglobin in muscles. The most significant muscle in the body is the heart.

Heartbeats are usually not noticeable. Electrical firings and muscle contractions take place quietly. When iron is too high or too low, the rhythm of heart becomes detectible as slow, rapid, fluttering or irregular. Sometimes pain (angina) is felt and other times no warning is given and the heart fails. For people with genetic hemochromatosis (iron overload) death by heart failure for untreated males is around age 58; for females with genetic hemochromatosis death by heart failure is around 20 years after the stop menstruating. For people with juvenile hemochromatosis or people who are undergoing multiple transfusions and develop iron overload, heart failure can occur at a much earlier age. And a less known fact is that death by heart failure for a person with severe iron deficiency anemia can happen at any age.

Much of what we know about iron in the heart comes from research that centers on people with iron overload at a young age, such as individuals with thalassemia, sickle cell disease, or juvenile hemochromatosis. The most significant research specific to adult onset hemochromatosis and cardiac iron comes from the US National Institutes of Health Hemochromatosis Protocol led by Dr. Susan Leitman and from Professor Dudley Pennell, Director of the National Institutes of Health Research Cardiovascular Biomedical Research Unit at Royal Brompton Hospital, London.

How do we see iron in the heart? 

Cardiovascular magnetic resonance imaging (CMR), sometimes known as cardiac MRI can reveal excess iron in the heart. This technology was perfected over the years because of early pioneers such as Herbert Bonkovsky who studied the use of magnetic resonance imaging to qualify iron in the liver. MRI techniques used to see iron in the liver are now being used to see iron in the heart.

How to remove iron from the heart? 

Phlebotomy or blood donation continues to be a safe and effective means of iron reduction when the removal frequency is in keeping with guidelines that do not overbleed or force a person into iron deficiency.  IDI Guidelines for iron reduction are in line with those used by the National Institutes of Health hemochromatosis protocol. Iron chelation* is used to remove iron from the heart for individuals who cannot tolerate phlebotomy generally due to low hemoglobin values, but we may begin to see use of iron chelation for hemochromatosis patients whose body iron levels are life-threatening and who may benefit from a secondary therapeutic approach.

Take action

Check Ferritin! Family history of heart attack, history of early death by heart failure, or any of the symptoms of impending heart attack listed above-especially heart arrhythmia-are good reasons to ask your physician to measure your serum ferritin level.  A healthy range for adults is between 50 and 100. This is a new range for ferritin and one of the changes to our reference charts that soon will be available. Also if you know of someone who craves chewing on ice, inform them about iron.

Among the most popular downloads for 2016 are: Boost Your Ferritin.pdf and Lower Your Ferritin.pdf.   

*Not to be mistaken for disodium ethylene-diamine-tetra-acetic acid (Na₂EDTA)

 

References:

1.        Alam MH, Auger D, Smith GC, et al. T1 at 1.5T and 3T compared with conventional T2* at 1.5T for cardiac siderosis. J Cardiovasc Magn Reson. 2015;17(1):102. doi:10.1186/s12968-015-0207-0.

2.        Ari ME, Ekici F, Çetin İİ, et al. Assessment of left ventricular functions and myocardial iron load with tissue Doppler and speckle tracking echocardiography and T2* MRI in patients with β-thalassemia major. Echocardiography. January 2017. doi:10.1111/echo.13463.

3.        Bonkovsky HL, Rubin RB, Cable EE, Davidoff A, Pels Rijcken TH, Stark DD. Hepatic iron concentration: Noninvasive estimation by means of MR imaging techniques. Radiology. 1999;212(1):227-234. doi:10.1148/radiology.212.1.r99jl35227.

4.        Distante S, Eikeland J, Pawar T, et al. Blood removal therapy in hereditary hemochromatosis induces a stress response resulting in improved genome integrity. Transfusion. 2016;56(6):1435-1441. doi:10.1111/trf.13588.

5.        Pennell DJ, Porter JB, Piga A, et al. Sustained improvements in myocardial T2* over 2 years in severely iron-overloaded patients with beta thalassemia major treated with deferasirox or deferoxamine. Am J Hematol. 2015;90(2):91-96. doi:10.1002/ajh.23876.

6.        Rabel A, Leitman SF, Miller JL. Ask about ice, then consider iron. J Am Assoc Nurse Pract. 2016;28(2):116-120. doi:10.1002/2327-6924.12268.