Patent Ductus Arteriosus and Its Surgical Treatment

Abstract

The remarkable success that has attended surgical ligation of the patent ductus arteriosus has aroused a new interest in a unique structure and has been the means of revealing striking gaps in our knowledge-of a comparatively common form of congenital heart disease. Unexpectedly , ligation of the infected ductus has shed a new light on the most serious of all forms of heart disease-bacterial endocarditis. Of vital importance in intra-uterine life, during which its purpose is to enable venous blood entering the heart from the superior vena cava to pass directly to the descending aorta and thence to the placenta without traversing the lungs (Barcroft, 1939), the arterial duct persisting after birth forms an arterio-venous fistula. Blood then flows continuously' in large quantities from the aorta to the pulmonary artery. Hence the patent ductus throws an added burden upon the heart and upon the pulmonary and to some extent the peripheral circulations. PROBLEMS OF THE PATENT DUCTUS Despite the enormous literature that has accumulated on this branch of congenital heart disease, we have not yet adequate solutions for many of the most fundamental of its problems. Theories and suggestions to account for the closure of the ductus are many, but the factors determining the natural process of occlusion, or permitting the persistence of the channel for months or years or throughout life, are mysteries for which so far we have no entirely satisfactory explanations. Wells (1908) and Abbot (1927) have summarized the more important suggestions advanced to account for the mechanism of closure, none of which in the light of present day knowledge can be regarded as adequate without experimental proof. Expansion of the bronchi compressing the ductus, inflation of the lungs with consequent readjustment of the thoracic viscera leading to stretching and obliteration of the ductus, local thrombosis within the duct as a result of changes in blood pressure in the two circuits, the occlusive effect of a valve-like fold of aortic endothelium overlying the orifice of the channel, the constrictive effect of the recurrent laryngeal nerve as the viscera sink lower in the thorax, are among the possibilities which in the past have been advanced and seriously considered by various authors. Kennedy and Clark (1942) and Kennedy (1942) have demonstrated that during late fcetal life the ductus arteriosus is an active structure, responsive to certain stimuli of which at least one favouring its prompt closure is, they believe, a rich oxygen supply either by inhalation or intravenously. By the injection of radio-opaque dye into the blood stream of foetal lambs delivered by Caesarean section, Barcroft and his collaborators (1938, 1939, 1941) have clearly demonstrated abrupt changes in the patency of the ductus so that functionally there is a rapid obliteration of its lumen even within five minutes of birth. Anatomical obliteration is a gradual process. The factors initiating the functional or primary closure, maintaining the muscular contraction of the du...

Patent ductus arteriosus in infants and children: A review of 936 operations (1946-69)

“…Harvey (1628) demonstrated its physiological importance in the fetal circulation (Gilchrist, 1945;Harvey, 1964;Skinner, 1961).…”

“…Gilchrist (1945) published a comprehensive review of the many anatomical, embryological, and experimental observations that have been contributed to the literature.…”

Name That Murmur — Eponyms for the Astute Auscultician

“…The murmur grows louder as the child ages and arterial dilation increases, and the area of maximal intensity may migrate farther left. 22,24 Gr aham S teell Murmur Scottish cardiologist Graham Steell was an avid horseman and iconoclast. He was known for his illegible notes, brevity of speech, and excellent bedside teaching.…”

Congenital Cardiac Disease A Pathologic Review

“…Just how long after a ductus arteriosus has been patent, it can close spontaneously cannot be answered with any finality, but the evidence suggests that a ductus arteriosus may be patent for as long as four years and then close spontaneously. 19 This concept obviously introduces a difficult therapeutic question, namely: "How soon after a patent ductus arteriosus is detected should it be ligated ?" It seems logical to recommend that if a patient is less than 5 years of age, the ductus arteriosus should not be ligated unless it is causing symptoms.…”