Pathology of idiopathic cardiomegaly in Jamaica

Twenty-one cases of idiopathic cardiomegaly which came to necropsy have been reviewed. Investigations included injection and x-ray studies, careful microscopical examination and skip serial sectioning of the conduction systems. The obvious feature was gross cardiomegaly in the absence of atheroma of the large coronary vessels and an associated fibrosis of the right and left bundle-branches. Three hearts showed thickening of the intramural vessels of 80æ to 400æ diameter. We suggest that such changes may be one of the causes of the ischaemic electrocardiographic findings reported in previous epidemiological surveys.(AU)

Prognosis of idiopathic cardiomegaly in Jamaica with reference to the coronary arteries and other factors

Clinical and epidemiological features of idiopathic cardiomegaly in Jamaica are reviewed, and the high community prevalence of the disorder is shown. The frequency occurrence of sudden or unexpected death in patients whose earlier electrocardiograms had shown repeated ventricular ectopic beats has been noted. Common electrocardiographic findings included a high rate of abnormalities usually regarded as indicative of coronary artery disease: cardiac arrhythmias, particularly multiple ventricular extrasystoles; and high voltage complexes characteristic of left ventricular hypertrophy. The differences and similarities between idiopathic cardiomegaly and coronary heart disease are shown. A possible role for intramuscular lignocaine in the control of the chronic ventricular ectopic rhythms is demonstrated. There is a statistically significant association between idiopathic cardiomegaly and positive serological tests for treponemal infection. The hearts are invariably hypertrophied at necropsy. In some hearts the smaller intramuscular coronary arteries show occlusive changes. Their possible nature and significance are discussed.(AU)