Prevalence of a haemochromatosis among men with clinically significant bradyarrhythmias.

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.