The development of cardiomegaly in homozygous sickle cell disease

Cardiomegaly is a feature of the physiological adaptation to chronic anaemia and is characteristic of many patients with sickle cell disease. This study documents that significant cardiomegaly develops in children with homozygous sickle cell(SS) disease before the age of one year. No correlation was found between the degree of cardiomegaly and the severity of aneamia. Abnormal cardiac signs are common in very young children with SS disease and do not necessarily imply cardiac dysfunction. (AU)

Some non-infective diseases endemic in the West Indies

The West Indies, and associated parts of the Caribbean area, are extremely diverse and afford interesting examples for the study of geographical medicine. Short accounts are given of some conditions whose aetiologies have been relatively recently clarified, including vomiting sickness of Jamaica, veno-occlusive disease of Jamaica, blackfat pulmonary fibrosis of Guyana, and epidemic acute glomerulonephritis of Trinidad. The aetiology of tropical sprue, which is common in Puerto Rico and absent from Jamaica remains to be explained although a hypothesis has been put forward. Further work is needed to establish the geographical distribution of idiopathic cardiomegaly and the spinal neuropathies and associated syndromes of retrebublar neuritis and sensorineural deafness before their aetiologies can be understood (AU)

Approach to assessment of risk factors in mild hypertension

Criteria are urgently needed for the early detection of subjects with only mildly raised blood pressure who may be at high risk of developing the complications of hypertension. As a step towards the establishment of such criteria we have examined the association of certain possible "risk" factors-namely, x-ray evidence of cardaic enlargement, high serum cholesterol levels, effort pain, E.C.G. abnormalities, and high systolic blood pressure-with fatal or morbid endpoints in a five-year follow-up study of subjects whose diastolic pressure had been found initially to be between 95 and 114 mm Hg. The index group consisted of 22 patients in whom these endpoints occured. They comprised death from cardiovascular disease, clinical or E.C.G. deterioration, and either an increase in diastolic pressure of at at least 10 mm Hg or a diastolic pressure of 115mm Hg or both. The control group consisted of 22 subjects chosen at random from other respondents with the same range of diastolic pressures and the same age and sex distribution. "Any two or more" of the possible risk factors examined were found to occur significantly more often in the index group than in the controls, suggesting a possible approach to the early detection of high-risk subjects. The value of long-term studies along these lines and the urgent need for them are emphasised (Summary)

Wenckebach phenomenon occurring in secondary syphilis

A case is described in which A-V nodal dysfunction in the form of the Wenckebach phenomenon occurred in a patient suffering from secondary syphilis. It was associated with a slight degree of cardiac enlargement. The patient presented with palpitations which resolved with antisyphilitic therapy, but the cardiac enlargement persisted. Electrocardiograms carried out on a further 49 consecutive patients with secondary syphilis showed no evidence of A-V nodal conduction defect. Abnormal eletrocardiograms were found in eight (16 per cent.) of the series, and in three (6 per cent.) the abnormality consisted of ST segment and T wave changes (AU)

Quantitative aspects of electrocardiograms of adults in a Jamaican rural population

The values of selected measurements from scalar electrocardiograms of a representative Jamaican population are reported. The tracings were obtained from 1067 adults aged 35 to 64 years, just under 90 percent of 1200 men and women selected randomly from a defined community of a hilly inland rural area. The participants were mostly small farmers, and their womenfolk, and they were of African origin. Measurements included intervals, axes, and amplitudes and three indices of left heart involvement-Morris's index of left atrial disease, Estes' score for left ventricular hypertrophy, and the Sokolow-Lyon criteria. Their distributions are compared with data from similar epidemiological studies and provide values for an ethnic group for which there are few population-based reports. The striking feature of these tracings was the high proportion with evidence of left ventricular hypertrophy, particularly those of men. The relation between certain electrocardiographic characteristics and age, body built, arterial pressure, and heart rate was investigated by multiple regression analysis, and this showed that little of the variation of most electrocardiographic measurements were explained by these variables. (AU)

Reappraisal of cardiovascular surveys in Jamaica: use of submaximal exercise tests for clinical investigation

Assertions that idiopathic cardiomegaly or an obscure form of ischaemic heart disease are common in Jamaica have been based on a high prevalence in community surveys of unexplained electrocardiographic abnormalities and of positive responses to a questionnaire for ischaemic heart pain. Thirty-one men, aged 42-62 years, in whom these abnormalities had been found in a previously surveyed rural community, were recalled for clinical examination and exercise tests and compared with 18 control subjects. No clinical abnormalities were found. The heart rates during standard work and maximum oxygen uptake of subjects and controls were similar, and indicated, on average, excellent exercise performance consistent with their heavy physical activity in daily life. None complained of chest pain at near maximal exertion, and the previous diagnosis of angina pectoris was judged to have been mistaken. Most of the electrocardiographic abnormalities at rest were minor or isolated and did not change on exercise. Significant changes in exercise occurred in 4 subjects, in whom inverted T waves and ST depression became less obvious than at rest, but the cause of these abnormalities was not found. Though idiopathic cardiomegaly and ischaemic heart disease do not occur in Jamaica, their incidence is not known but there is no evidence that they are as widespread as has been previously asserted. Interpretations of answers to questionnaires and of electrocardiograms obtained in population surveys should be made with caution. From this study we have no evidence on whether the electrocardiographic changes were related to ethnic or environmental factors. (AU)

Gross cardiac involvement in glycogen storage disease type 3

This report describes a patient with type 3 glycogenosis diagnosed during life but who died suddenly at home and was found at necropsy to have gross cardiac involvement. The immediate cause of death was not apparent but could possibly have been related to the very unusual degree of cardiac involvement (AU)

Jamaican idiopathic cardiomegaly, a possible variant of the athletic heart syndrome in men with high levels of customary activity - abstract

A cardiovascular survey in a rural Jamaican community identified a group with suspected early idiopathic cardiomegaly. Forty and seven normotensive men and women respectively were investigated for further evidence of this disease, and to search for clues to its aetiology. There were: 12 men with large Q waves, 6 men with short P-R interval (pre-excitation), 8 men with prolonged A-V conduction, 9 men with very unusual electrocardiograms, considered most likely to have idiopathic cardimegaly, 5 men with positive responses to an angina questionnaire, 7 women with T-wave inversion in precordial leads. Their results were compared with those of twelve men without evidence of cardiovascular disease. After interview, examination and anthropometry, cardio-respiratory and electrocardiographic excercise responses were measured on a cycle ergometer while subjects exercised to a pulse rate 90 percent of the predicted maximum. Fourteen men performed maximal exercise studies. The great majority of men, but no women, had high levels of customary activity imposed by the terrain of their working environment, and correspondingly athletic responses to the excercise test. No subject developed angina or ECG ischaemia, but five men had a significant excercise arrythmia. At an oxygen intake of 1.51/min the means of cardiac frequency (Cf1.5) and minute ventilation (VE1.5) for the 52 men were 114/min and 43.4 litres respectively. Corresponding values for women were 151/min and 52.7 litres. Mean maximal oxygen intakes/kg lean body mass were 51.5 ml for men and 42.9 ml for women. The athletic performance, low resting pulse, radiographic cardiomegaly, and distinctive electrocardiogram of these men are all features of the athletic heart syndrome, in which potentially dangerous arrythmias can lead to sudden death. It is suggested that some examples of Jamaican idiopathic cardiomegaly in men may be due to a disorder of cardiac rhythm that develops in subjects with ventricular hypertrophy (AU)

The pathology of idiopathic cardiomegaly in Jamaica - abstract

Since 1966 twenty-five cases of idiopathic cardiomegaly (ICM) have been examined at post mortem in the Pathology Department, University of the West Indies. Hearts were injected with micropaque and coloropaque and subsequently X-rayed to study the vasculature, including the microvasculature. Microscopic sections of various parts of the heart together with skip sectioning of the conduction system were done. Microscopically the hearts were heavy and dilated, with no abnormality of the valves or coronary vessels. Half of the hearts had thrombi (mostly small) in one or more of the four chambers, but endocardial thickening was minimal. Microscopically the changes in the myocardium were non-specific but twenty of the twenty-five hearts showed some pathology in the conduction system particularly the left bundle branch. Four of the hearts showed thickening of the intramural vessels of the interventricular septum. The microvascular pattern of ICM is different from that of the normal heart and also different from the atherosclerotic and hypertensive hearts (AU)

The prognosis of idiopathic cardiomegaly in Jamaica with reference to the coronary arteries and other factors: clinical aspects - abstract

The mode of death, and the factors which appear to influence the prognosis of idiopathic cardiomegaly have been examined. In more than half the deaths in patients with idiopathic cardiomegaly, death was sudden or unexpected. Electrocardiograms recorded on patients with idiopathic cardiomegaly showed a high rate of abnormalities commonly regarded as indicative of coronary artery disease (36 percent in men and 50 percent in women), a high prevalence of cardiac arrhythmias, particularly multiple ventricular extrasystoles; and high voltage complexes characteristic of left ventricular hypertrophy. Fifty seven per cent of patients whose death was unexpected or sudden, showed multiple ventricular ectopic beats. The differences and similarities between idiopathic cardimegaly and coronary heart disease have been shown. It is concluded that the background of some cases of idiopathic cardiomegaly may be myocardial ischaemia occurring at a gradual and insidious pace, and probably diffusely involving a smaller category of coronary vessel. A possible role for intramuscular Lignocaine in the control of the chronic ventricular ectopic rhythms has been demonstrated. There was a statistically significant association between idiopatic cardiomegaly and positive serological tests for treponemal infection (AU)

Immunological studies on leakage of heart antigens in Jamaican cardiomyopathies

Antibodies to cow-heart tissue were prepared in mice. These antibodies were used to demonstrate the presence of cardiac antigens in sera of patients with cardiac disease. Normal individuals gave positive reactions, but to a lesser extent (AU)

Characteristics relevant to cardiovascular disease among adults of African and Indian origin in Guyana

Characteristics relevant to cardiovascular disease, including anthropometry, arterial blood pressure, serum cholesterol levels, chest radiography and electrocardiography, were investigated in a survey of 843 men and women aged 35-54 years of African and Indian origin living in 2 communities in Guyana. Clinical experience suggested a high incidence of hypertension and a low incidence od ischaemic heart disease. Africans were taller and heavier than Indians but their other characteristics were, in general, similar except that their mean blood pressure levels and R amplitudes in certain ECG leads were consistently higher. Hypertension was common and was more significantly correlated with obesity and , probably independently, with body size. Serum cholesterol levels, with mean values of about 222mg/100ml, were strongly correlated with factors associated with obesity in men but not women. Cardiothoracic ratios, measured from chest films, were greater than values regarded as normal for Europeans because of a relative narrowness of thoracic diameters. Prevalence of S-T-segment and T-wave defects in ECGs classified by the Minnesota Code was as high as reported from communities where ischaemic heart disease is clinically more frequent. Hypertension, cardiac enlargement, obesity and cholesteraemia were more prevalent when defects involved lateral leads(I, aVL, V5 and V6) than in subjects with normal ECGs, suggesting that the majority of important abnormalities occurred primarily in the left ventricle and were probably related to hypertension rather than to coronary insufficiency without hypertension. Analysis od S-T and T-wave defects, both of blood pressure and by lead position, might show meaningful differences between populations which, by present methods of presentation, appear to have surprisingly similar prevalences of ECG abnormalities.(AU)

Relatively benign sickle-cell anaemia in 60 patients aged over 30 in the West Indies

A study in Jamaica of 60 patients with sickle-cell anaemia over the age of 30 years showed that most of them were in full-time employment. Pains in the bones or joints, leg ulceration, and jaundice were the most frequent types of presentation, but only two patients had a haemoglobin level consistently below 6 g./100 ml. Most of the patients were well developed and of average height, and, though the development of secondary sexual characteristics was delayed, there was an average of 2.6 pregnancies per patient. These findings suggest that the course is more benign than has been realized. (AU)

Idiopathic cardiomegaly

Cardiomyopathies are certain heart diseases of unknown etiology and pathogenesis, occurring mostly in tropical and subtropical areas, where they constitute a major clinical problem and sometimes a public health problem. The need for international co-operation in the study of such forms of heart diseases has long been recognized and WHO convened informal meetings of investigators on various aspects of the subject in 1964, 1965 and 1966. Out of these have arisen co-operative studies co-ordinated by WHO. In November 1967 a fourth informal meeting was held in Kingston, Jamaica, to review the following topics: the progress reports from all co-operating laboratories; the diferent types of cardiomyopathies; past experience with cardiac registries, and the diagnostic importance of coronary angiography. Steps were taken towards the formulation of a standard terminology, since too many confusing names are currently employed to mean "cardiomegaly of unknown origin". A common name, "idiopathic cardiomegaly", was therefore suggested for further use. The account presented here was prepared by Dr. Z. Fejfar, Chief Medical Officer, Cardiovascular Diseases, World Health Organization, Geneva, on behalf of the other participants and is a precis of some of the information that was exchanged, some of the views that were expressed and of the suggestions that were made.(AU)

Jamaican cardiomyopathy

Eight cases of cardiomyopathy found in Jamaica are described. The ages ranged from 19 to 60 years. There were six men and two women. All the hearts were enlarged, the weights ranging from 480-370 g, except for one patient in whom the heart weighed 275 g. The principal pathological finding was fibrous thickning of the endocardium confined to the left side in seven patients and most evident in the ventricles. Four hearts showed mural thrombi which in two instances had given rise to systemic emboli. Valvular involvement -slight-was seen in only three patients. The endocardial thickenings contained deposits of fibrin and originated from them. This cardiomyopathy resembles most closely "heart muscle" disease found in Nigeria (Summary)

Heart weight of Jamaicans: autopsy study of normal cases of hypertension and chronic lung disease

The heart weight and the weights of the component parts have been measured in a group of 126 Jamaicans of African origin on whom autopsy was performed at the Pathology Department of the University of the West Indies. This series comprised 58 normal cases, 46 cases of hypertension, and 22 cases of chronic lung disease. The mean heart weight for normal males was 294.5 g and for females 258.5 g. These figures are similar to those reported from Uganda but less than those from Britain and North America. The differences in heart weight are probably correlated with difference in body size. Total heart weight in the hypertensives was greater than in normals because of left ventricular hypertrophy. In chronic lung disease total heart weight was greater than that of normals due to enlargement of the right ventricle and of the combined atria. Right ventricular weight was also increased in cases of hypertension. (AU)

Spontaneous rupture of a papillary muscle of the heart

An unusual case of ruptured papillary muscle of the heart is desired. The study of serial sections revealed a small aneurysm in the ruptured papillary muscle. The cause of the aneurysm was not certain but it was probably syphilitic. (Summary))