Adrenocortical Steroids in Intermittent Heart-block
Authors: B. W. Pay
Journal: BMJ (1961)

confirmed by cardiac catheterization.There was evidence of chronic elevation of left atrial pressure apart from the raised " wedge " pressures obtained at catheteri- zation.The electrocardiogram showed left atrial hypertrophy as in mitral stenosis, and at necropsy there was great atrial hypertrophy without dilatation in some cases.Severe left atrial hypertension is in contrast to the simple systolic type of hypertension which exists in pure rheumatic mitral incompetence in Europeans.In these patients the ventricular diastolic inflow may be impeded by stiffness of the hypertrophied myocardium associated, in some cases, with the occlusive and splinting effects of endomyocardial fibrosis.It is therefore probable that the pulmonary hypertension is, as in many cases of mitral stenosis, due to the passive effects of the high left atrial pressure coupled with a vasoconstrictive element at a precapillary level.It remains to mention the possibility that pulmonary vasoconstriction is an excessive response to the pulmonary venous hypertension because of chronic anaemia or some other unknown factor.Left atrial hypertrophy, in contrast to dilatation, parallels the absence of atrial fibrillation.It is probable that atrial systole is an essential component in the maintenance of a cardiac output sufficient to sustain life in these patients.Finally, we wish to stress the importance of the soil in which this form of heart disease thrives.Anaemia is usual; intestinal parasitism is rampant; in addition malaria is endemic, and the dysenteries, both bacterial and protozoal, are widespread.Protein malnutrition is rife, especially in infants and children.In the presence of persistent chronic ill-health of this nature it is difficult to believe that the myocardiufm remains unaffected and healthy.It is probable that anaemia alone, when severe and protracted, may lead to cardiomyopathy (Somers, 1959).On top of all this it must be emphasized that these patients are always ambulant, and never rest unless it is physically impossible for them to stand and walk.This continued physical activity may have further adverse effects upon an already damaged myocardium. SummaryThe clinical, radiological, and electrocardiographic features of 50 Nigerian patients who presented with heart failure due to mitral incompetence and pulmonary hypertension have been investigated.Necropsy exami- nation of 13 cases showed that there was severe left ventricular myocardial disease and mitral-valve disease.Most hearts showed some degree of macroscopic endomyocardial fibrosis, and histological examination revealed either a diffuse non-specific inflammatory reaction or a myocarditis with Aschoff nodules which was indistinguishable from rheumatic carditis.It is suggested that the peculiar pattern of this disease, comprising left ventricular myopathy, mitral valvulitis, and pulmonary hypertension, may be determined not only by its primary cause, but also by the background of chronic anaemia, protein malnutrition, and chronic infestation which is present in these patients and in the population from which they are drawn.