The significance of the enlargement of the aortic shadow in adult Nigerians.

A study of the width of the aortic shadow and of the cardiothoracic ratios in 183 chest radiographs, of persons over the age of 35 years, shows that hypertension produces a constant enlargment of the aortic shadow. The study suggests that gross enlargement, in the absence of disease of the aorta or of the aortic valves, is a result of hypertension. The authors suggest that this enlargement is valuable in delineating a sub-group of cases of myocardial failure in which the primary cause of failure may be hypertension. Cases with gross aortic arch dilation and no detectable cardiovascular disease often have cardiomegaly. The question of the possibility of remission of untreated hypertension is raised.