Pulmonary hypertension due to pulmonary arterial coarctation.

Abstract

With improved diagnostic methods many diseases which were previously grouped together as idiopathic can now be separated into etiologic categories. Essential pulmonary hypertension may succumb to reclassification, since several types are now found to be distinguishable on the basis of definite radiological and pathological changes (1, 27, 54). It is not only our duty to refine these idiopathic categories, but it is our privilege as physiologically oriented radiologists to try and understand the basic changes which make this refinement possible (49). There have been many recent reports (2, 6, 11, 14, 20, 41, 45, 48, 51, 53, 55, 58, 60) on supravalvular or postvalvular constriction, coarctation, or stenosis of the pulmonary arteries. Four mention the association of pulmonary hypertension with this condition (2, 11, 14, 41). It is our observation that the two are always associated. Four reports have appeared in the radiologic literature. This is apropos, since coarctation of the pulmonary artery can be diagnosed radiographically. Despite the manifest recent interest in the radiological anatomy of the pulmonary arteries and in the physiology of the lesser circulation, coarctation of the pulmonary artery was not even discussed in the recent International Symposium on the Pulmonary Circulation sponsored by the Chicago Heart Association in March 1958. It seems that up to the present the relationship between pulmonary hypertension and pulmonary coarctation has not been firmly established or generally recognized. Method of Study Three general methods of study are presented: first, an analysis and review of our own cases; second, an attempt to produce pulmonary arterial coarctation anatomically and to observe the effects, if any, upon the pulmonary blood pressure; third, a review of the world literature on the pulmonary artery coarctation made in an attempt to detect patterns, similarities, or syndromes which would prove helpful in the diagnosis. From clinical and angiocardiographic observations it appeared to us that such a relationship was a very likely probability. The intermediary between the anatomical malformation and its physiologic manifestation could be a hypothetical humoral material, a neurogenic response or a hydrostatic reaction to the mechanical constriction observed. This problem seemed to invite a combined radiological and physiological experimental attack. The major premise, however, is the only one which we have tested. The secondary hypotheses are in the process of exploration. Clinical Observations Seven children who were seen in the cardiac clinics of the University of California (Los Angeles) were found to have pulmonary arterial coarctation. All of these children had pulmonary hypertension. During this same three-year period 68 other children with pulmonary hypertension were observed among 330 who had had diagnostic heart catheterization and/or angiocardiography.