Persistent Left Superior Vena Cava Draining the Pulmonary Veins

Abstract

Persistence of the left superior vena cava is not uncommon in children with congenital heart disease and is occasionally found in adults at thoracotomy. The anomalous vena cava usually carries venous blood from the upper part of the body to the right atrium via the coronary sinus and has little functional significance. In the four patients we describe, however, the left superior vena cava drained arterial blood from some or all of the pulmonary veins into the left innominate vein, and thence into the right atrium. In three of them it was the sole channel by which oxygenated blood could reach the systemic circulation.We record these cases because we believe that the anomaly is more common than has been thought, and gives a clinical picture sufficiently distinctive to be recognized in life, and because it is one for which surgical relief may prove feasible. We have found only two similar cases of which an account of the physical signs has been given and in neither was the diagnosis made in life (Taussig, 1947).Before describing the clinical picture it is necessary to consider briefly the development of the superior vena cava. EMBRYOLOGY Marshall (1850), a century ago, appears to have been the first to give an embryological explanation of the persistence of a left superior vena cava.A modern account of the anomaly (Hamilton et al., 1945; Patten, 1946) is as follows. The venous system arises from the same network as the arterial system and the capillaries. Very soon three pairs of venous channels are recognizable, namely (i) the two vitelline veins, which pass from the yolk sac along the roof ofthe primative gut to meet (ii) the umbilical veins at the sinus venosus and (iii) the cardinal veins which also enter the sinus venosus. Each cardinal vein consists of two parts, the anterior cardinal or precardinal vein and the posterior cardinal or postcardinal vein. The precardinal and p6stcardinal veins unite on each side of the primative heart tube to form a short vessel, the common cardinal duct or duct of Cuvier which enters the horn of the sinus venosus (Fig. 1).The lung bud arises as an outgrowth from the primitive foregut. Both these structures are covered by a common venous network, the splanchnic plexus. The contiguous primitive pulmonary venous plexus and primitive splanchnic venous plexus drain into the paired precardinal and postcardinal veins and into the vitello-umbilical veins (Fig. 3A)

Mitral Stenosis Associated with Anomalous Pulmonary Venous Drainage into a Left Superior Vena Cava

“…%, which might be within the range of experimental error, it is possible that their patient in fact had total pulmonary venous drainage into a left superior vena cava. The normal arterial oxygen saturation in their patient would not exclude this possibility, as a similar finding was noted in a proved case by Gardner and Oram (1953). In the case reported here, although only part of the venous drainage of the lungs was into the left superior vena cava, the typical " cottage-loaf " cardiovascular shadow was present and was explained by the additional presence of tricuspid incompetence with subsequent increased prominence of the superior vena caval shadow.…”

“…ANOMALOUS PULMONARY VENOUS DRAINAGE MEDIBCL JoURNAL 1021 Discussion Although mid-diastolic apical murmurs may be heard in cases of anomalous pulmonary venous drainage (Gardner and Oram, 1953;Whitaker, 1954), a confident diagnosis of mitral stenosis was made in this patient because of the presence of an enlarged left atrium fluoroscopically, and a well-marked opening snap clinically. In view of the grave condition of the patient it was decided to perform a mitral valvotomy before undertaking any special investigations such as cardiac catheterization.…”

“…Grishman et al (1951) reported a case of partial anomalous pulmonary venous drainage, and the teleradiogram reproduced in their report showed the typical " figureof-8" appearance. However, as the difference in oxygen content between blood from the right atrium and the femoral artery was only 0.5 vol.…”

“…Healey (1952) collected from the literature 144 cases and added three of his own. Excellent reports on the clinical features and the findings on cardiac catheterization and angiocardiography have been published by Snellen and Albers (1952), Gardner and Oram (1953), and Whitaker (1954). I have not been able to find a report in the literature of the association of anomalous pulmonary venous drainage with mitral stenosis.…”

Total Anomalous Pulmonary Return

“…The remaining nine patients had this diagnosis confirmed at the time of surgery or autopsy. The data are presented in table 2. A striking feature is the high oxygen saturation of the right atrial blood.…”