The heart is almost always affected in idiopathic (primary) hemochromatosis.

In addition cardiac iron deposits occur in secondary hemochromatosis, which occurs, for example, in patients who have received multiple blood transfusions for treatment of anemia.

The degree of involvement may be slight and without evidence of gross changes, but often it is sufficient to produce a brownish discoloration of the myocardium.

The deposits are more prominent in the subendothelial than in the subepicardial zone. Microscopically, hemosiderin granules are identified within myocardial fibers and occasionally in the connective tissue cells.

In the myocytes, the iron is deposited in sarcoplasmic siderin granules, which are distinct from lipofuscin granules. Varying degrees of degeneration, edema, and fibrosis of the myocardium can be seen.

Electrocardiographic changes and even cardiac failure may occur.

Arrhythmias may occur as a result of iron deposits in the fibers of the conduction system.

Endomyocardial biopsy in hemochromatosis: clinicopathologic correlates in six cases.J Am Coll Cardiol. 1989 Jan;13(1):116-20.

Clinical and pathologic features of cardiac hemochromatosis diagnosed by endomyocardial biopsy in six men, aged 32 to 75 years (mean 52), are described. Echocardiography demonstrated left ventricular enlargement and marked global systolic dysfunction in five. Cardiac catheterization demonstrated normal coronary arteries, increased left ventricular end-diastolic pressure and decreased left ventricular systolic function in all five so studied. Stainable iron was present in all endomyocardial biopsy specimens from the five patients with decreased left ventricular systolic function. Histologically, iron was detected only within the sarcoplasm, and its extent varied inversely with ventricular function. Thus, cardiac hemochromatosis represents a storage rather than an infiltrative disease. These results indicate that stainable iron is consistently observed in endomyocardial biopsy specimens from patients with impaired left ventricular systolic function. Iron staining is recommended for endomyocardial biopsy specimens from patients with idiopathic cardiac dysfunction.

Significance of left atrial contractile function in asymptomatic subjects with hereditary hemochromatosis.Am J Cardiol. 2006 Oct 1;98(7):954-9. Epub 2006 Aug 15

Patients with hereditary hemochromatosis (HH) have been reported to develop diastolic functional abnormalities detectable by echocardiography, but it is unknown whether these occur in asymptomatic subjects. Thus, this study tested whether echocardiographic left ventricular (LV) relaxation abnormalities are detectable in subjects with asymptomatic HH. Forty-three asymptomatic subjects with HH (C282Y homozygosity in the HFE gene) and 21 age- and gender-matched control subjects without known HFE mutations underwent echocardiography with comprehensive diastolic functional evaluations. Subjects with HH were in New York Heart Association functional class I and consisted of 22 newly diagnosed patients (group A) and 21 chronically phlebotomized subjects with stable iron levels (group B). Group A subjects showed significant iron overload compared with group B subjects and controls (group C) (ferritin 1,164 +/- 886 [p <0.05 vs groups B and C], 128 +/- 262, and 98 +/- 76 microg/L and transferrin saturation 79 +/- 19% [p <0.05 vs groups B and C], 42 +/- 21%, and 26 +/- 10% for groups A, B, and C, respectively). Echocardiographic evaluation revealed (1) no statistically significant abnormalities of Doppler LV relaxation in HH groups; (2) significant augmentation of atrial contractile function in subjects with HH compared with controls, which was not correlated with iron levels and treatment status; and (3) the preservation of overall LV systolic function in HH groups. In conclusion, the results of this study suggest that the augmentation of atrial contraction appears to be an early detectable echocardiographic cardiac manifestation of abnormal diastolic function in asymptomatic subjects with HH, which may reflect undetectable subclinical LV relaxation abnormalities.

HFE mutations in idiopathic dilated cardiomyopathy.Med Klin (Munich). 2006 Mar 22;101 Suppl 1:135-8

BACKGROUND AND PURPOSE: Dilated cardiomyopathy is a typical complication of hereditary hemochromatosis (HH). The present study investigated, whether mutations of the hemochromatosis (HFE) gene might be etiologic and disease-modifying factors in idiopathic dilated cardiomyopathy PATIENTS AND METHODS: Clinical and biochemical assessment and HFE gene analysis were perfomed in 46 patients with IDCM and 350 healthy controls. Cardiomyopathy was angiographically defined according to the criteria of the Collaborative Research Group of the European Human and Capital Mobility Project of Familial Dilated Cardiomyopathy. RESULTS: A higher prevalence of C282Y homozygosity was found among patients with IDCM compared to healthy subjects (4.3% vs. 0.6%; p < 0.02). A total of 6.5% of the patients with IDCM were either C282Y homozygotes or C282Y/H63D compound heterozygotes. The C282Y allele frequency was somewhat higher among patients with IDCM (8.7%) compared to healthy controls (5.4%; p < 0.2), whereas the H63D allele frequency was not increased. No significant differences of serum iron, ferritin or transferrin saturation, cardiac iron loading, NYHA classification, Lown's classification, the history of cardiopulmonary resuscitation, LVEDD (left ventricular end-diastolic diameter), EF (ejection fraction), LADD (left atrial end-diastolic diameter) and CI (cardiac index) were seen between HFE carriers and noncarriers. CONCLUSION: The present study indicates that it is worth screening patients with IDCM for iron parameters given the increased prevalence of disease-predisposing HFE constellations. It remains unclear, to what extent iron or immune-mediated processes contribute to the pathomechanism of IDCM.

Role of L-type Ca2+ channels in iron transport and iron-overload cardiomyopathy.J Mol Med. 2006 May;84(5):349-64. Epub 2006 Apr 8.

Excessive body iron or iron overload occurs under conditions such as primary (hereditary) hemochromatosis and secondary iron overload (hemosiderosis), which are reaching epidemic levels worldwide. Primary hemochromatosis is the most common genetic disorder with an allele frequency greater than 10% in individuals of European ancestry, while hemosiderosis is less common but associated with a much higher morbidity and mortality. Iron overload leads to iron deposition in many tissues especially the liver, brain, heart and endocrine tissues. Elevated cardiac iron leads to diastolic dysfunction, arrhythmias and dilated cardiomyopathy, and is the primary determinant of survival in patients with secondary iron overload as well as a leading cause of morbidity and mortality in primary hemochromatosis patients. In addition, iron-induced cardiac injury plays a role in acute iron toxicosis (iron poisoning), myocardial ischemia-reperfusion injury, Friedreich ataxia and neurodegenerative diseases. Patients with iron overload also routinely suffer from a range of endocrinopathies, including diabetes mellitus and anterior pituitary dysfunction. Despite clear connections between elevated iron and clinical disease, iron transport remains poorly understood. While low-capacity divalent metal and transferrin-bound transporters are critical under normal physiological conditions, L-type Ca(2+) channels (LTCC) are high-capacity pathways of ferrous iron (Fe(2+)) uptake into cardiomyocytes especially under iron overload conditions. Fe(2+) uptake through L-type Ca(2+) channels may also be crucial in other excitable cells such as pancreatic beta cells, anterior pituitary cells and neurons. Consequently, LTCC blockers represent a potential new therapy to reduce the toxic effects of excess iron.

Juvenile haemochromatosis presenting as intractable congestive heart failure.Orv Hetil. 2005 Dec 18;146(51):2605-8.

Juvenile haemochromatosis is an autosomal, recessive inherited iron metabolism disorder. The rapid deterioration and malignant prognosis differentiate juvenile haemochromatosis from hereditary haemochromatosis. The authors summarize the history of a 25 year old man, who worked in Hungary as a guest worker living in Romania. No significant illness has occurred in his previous history. The abdominal pain was his first symptom and he was treated in different institutions, where cholecystitis, alcoholic hepatic disease, hepatic cirrhosis were considered as a cause of his symptoms. Some weeks later atrial tachycardia, and congestive heart failure were observed and he was sent to our Cardiology Department. The echocardiography revealed diffuse hypokinesis, serious systolic dysfunction (ejection fraction: 21%), grade II mitral and tricuspid insufficiency with pulmonary hypertension. Considering the rapid deterioration of his cardiac function, myocarditis was suspected. Myocardial biopsy and coronary arteriography were performed. Coronary arteries were normal. Ventricular fibrillation occurred during coronary arteriography. Myocardial biopsy revealed juvenile haemochromatosis. Special laboratory examinations (transferrin saturation) were made after biopsy, that also confirmed the diagnosis of juvenile haemochromatosis. Cardiac transplantation was planned. Some days after the diagnosis was made the patient died of cardiogenic shock and intractable heart failure. Autopsy revealed hypogonadism and serious haemochromatosis in different parenchymal organs. Juvenile haemochromatosis should be considered in every young patient with congestive heart failure of unknown etiology.

Juvenile hemochromatosis HJV-related revealed by cardiogenic shock.Blood Cells Mol Dis. 2004 Sep-Oct;33(2):120-4.

Hemochromatosis is a heterogeneous genetic disease. Juvenile hemochromatosis is a severe rare recessive autosomal disease. Herein, we report a consanguineous family linked to a mutation in the recently identified HJV gene. A refractory cardiogenic shock had revealed hemochromatosis in the proband, a 26-year-old woman, and led to the death by heart failure. Regular phlebotomies in her young sister, which was also affected, had allowed to prevent the severe complications of the disease. These two affected subjects presented an identical homozygous haplotype at the 1q21 chromosome region and a missense homozygous mutation at the HJV gene (Arg288 > Trp). This observation underlines the importance of HJV genetic testing, by complete screening of the gene, in young patients with abnormal iron parameters and hypogonadism and/or cardiac symptoms to prevent death from cardiac complications.

Sudden cardiac death in hereditary hemochromatosis: an underestimated cause of death?Int J Legal Med. 2004 Jun;118(3):174-7. Epub 2004 May 7

Hereditary hemochromatosis (HH) is a frequent autosomal recessive disease which causes iron-overload of various organs. Of all northern European affected individuals, 90-95% show 1 of 3 known point mutations in the HFE gene. Symptoms and organs involved can vary considerably: Only a small fraction of the 200,000-400,000 persons affected in Germany develop the classical picture of liver cirrhosis and/or pancreatic fibrosis. Nevertheless, the life expectancy of persons with moderate or even subclinical symptoms is reduced, in many cases due to myocardial damage leading to cardiomyopathy with greatly increased risk of sudden cardiac death. Although the high prevalence of HH suggests that sudden cardiac death due to cardiac HH is a relatively common cause of death, the forensic literature lacks such reports. We present the case of sudden cardiac death in a young man with histological findings of massive cardial hemochromatosis which is characterized by the fact that none of the three known mutations for HH were found. This case demonstrates that genetic screening alone might not be sufficient to identify all persons at risk to developing HH.

Ventricular tachycardia and cardiac hemochromatosis. Rev Esp Cardiol. 2001 Nov;54(11):1328-31.

Hemochromatosis is characterized by an excessive iron deposit in different tissues. Cardiac involvement may be observed in one third of the patients due to hemochromatosis and occurs as a consequence of ferritin accumulation in the heart which on one hand induces alterations in systolic and diastolic ventricular function and on the other hand, an arrythmogenic substrate. The clinical manifestations can be indistinctly related to atrial tachyarrhythmia, ventricular tachyarrhythmia, atrio-ventricular blockade and congestive heart failure, with the first being the most frequent. We present the case of one patient with secondary hemochromatosis to repeated transfusions due to sideroblastic anemia with cardiac involvement, whose initial heart manifestations were recurrent atrial tachyarrhythmia and sustained ventricular tachycardia with syncope for which an automatic defibrillator was implanted.

Cardiac dysfunction because of secondary hemochromatosis caused by congenital non-spherocytic hemolytic anemia.
Jpn Circ J. 2001 Feb;65(2):126-8.

Most patients diagnosed with secondary hemochromatosis have had repeated blood transfusions. Cardiac failure accounts for approximately one-third of the deaths associated with hemochromatosis. Liver dysfunction or hormonal disorders such as diabetes generally precede cardiac failure. A 23-year-old woman with hemochromatosis had, despite significant left ventricular dysfunction, liver function within the normal range on biochemical evaluation. She was treated for congestive heart failure and given desferoxamine intravenously. She did not have primary hemochromatosis, and had not received multiple blood transfusions or iron supplement. As a child the patient had been diagnosed with congenital non-spherocytic hemolytic anemia not requiring transfusion; thus, this is a unique case of secondary hemochromatosis.

Cardiac pathology of extracardiac origin (II). The cardiac repercussion of amyloidosis and hemochromatosis.Rev Esp Cardiol. 1997 Nov;50(11):790-801

Although rare, amyloidosis and hemochromatosis are the infiltrative diseases in which the heart is more frequently involved. The most common clinical presentation is heart failure with hemodynamic features of restrictive heart disease in cardiac amyloidosis. The diagnosis is often made because of symptoms of other organ involvement, although sometimes cardiac symptoms may be the initial manifestation. The non-specific clinical presentation and the low prevalence of these cardiomyopathies make the diagnosis difficult if the clinician does not suspect it. Once symptoms develop, the evolution is fast. Usually, the unsatisfactory and ineffective treatment of amyloidosis and hemochromatosis contribute to the poor prognosis. The indication of cardiac transplantation in advanced cases is questionable because of the high recurrence of the illness.

Prevalence of a haemochromatosis among men with clinically significant bradyarrhythmias.Eur Heart J. 1989 May;10(5):473-8

Cardiac involvement in haemochromatosis includes development of congestive heart failure and/or cardiac arrhythmias. To elucidate the importance of this disorder among patients with severe cardiac bradyarrhythmias necessitating treatment with a permanent pacemaker, such patients were screened for evidence of iron overload. Serum ferritin was determined in 232 men treated with a permanent pacemaker. In six patients (2.6%) the serum ferritin values were twice the upper normal limit. In three of these, causes other than iron overload were found (liver cancer, myeloma and amiodarone treatment), while in three (1.3%) iron overload was suspected. All the latter three had atrioventricular block of second to third degree. In these patients percutaneous liver biopsy was performed. The specimens were examined by light and electron microscopy and the iron content was determined by atomic absorption spectrophotometry. The results of these investigations showed iron overload in the liver. The prevalence of iron overload (2.0%) among this male pacemaker-treated population with AV block II-III is significantly higher than the rates previously found in urban populations in Sweden. The present data indicate that screening for haemochromatosis is of importance among males with second and third degree atrioventricular-block of unknown etiology.

Cardiomyopathy as the cause of death in genetic hemochromatosis-.Z Gastroenterol. 1996 Mar;34(3):178-82.

Hemochromatosis is an autosomal-recessive disease which causes iron-overload of various organs including liver, pancreas and heart. This report analyzes the course of hemochromatosis in two patients (a 28-year-old man and a 57-year-old woman) in whom hemochromatosis was detected because of severe cardiomyopathy. Initial symptoms were edema, anasarca and dyspnea. Further examinations showed pleural effusion, decreased left-ventricular-function, skin pigmentation, diabetes mellitus and liver cirrhosis. Although phlebotomy treatment and iron-chelation therapy with deferoxamine initially resulted in some improvement, both patients died from cardiomyopathy three months after diagnosis. The reports of these two cases underline that hemochromatosis-associated cardiomyopathy is often irreversible if severe congestive heart failure is present. In cardiac decompensation heart transplantation has to be considered as early as possible.

Cardiac iron deposition in idiopathic hemochromatosis: histologic and analytic assessment of 14 hearts from autopsy.J Am Coll Cardiol. 1987 Dec;10(6):1239-43