Termination of Left Superior Vena Cava in Left Atrium, Atrial Septal Defect, and Absence of Coronary Sinus

Abstract

Eight cases of termination of the left superior vena cava in the left atrium are reviewed pathologically and clinically. In three of the five patients who died, pathologic examination revealed three anomalies which, together, are considered to form a developmental complex. The anomalies are (1) termination of the left superior vena cava in the left atrium, (2) absence of the coronary sinus, and (3) an atrial septal defect lying in the postero-inferior angle of the atrial septum. In the two remaining fatal cases, the aforementioned anomalies were associated with persistent common atrioventricular canal. In this situation, the atrial septal defect of the latter malformation was confluent with the atrial septal defect of the anomalous complex described. The coexistence of three anomalies-the left superior vena cava terminating in the left atrium, absent coronary sinus, and atrial septal defect-is considered to result from a single developmental abnormality. This takes the form of failure of complete formation of the left atriovenous fold, that fold which normally develops along the left side of the junction of the sinus venosus and the atrial portion of the heart. Clinically, features of increased pulmonary blood flow, coupled with duskiness of the skin, were the significant abnormalities. When cardiac catheterization was attempted through a right-sided vein, the data revealed a left-to-right shunt at atrial level, while levels of arterial oxygen desaturation were present. Except in cases with coexistent ventricular septal defect, pulmonary hypertension was absent. In each of the four patients in whom cardiac catheterization was performed through a left antecubital vein, the catheter was advanced into the left superior vena cava, left atrium, and left ventricle. This was substantiated by angiocardiography in three of the four patients. In our experience, angiocardiography was the most reliable procedure to substantiate the termination of the left superior vena cava in the left atrium. The present study suggests that, in the absence of pulmonary hypertension, a left-to-right transatrial shunt associated with systemic arterial oxygen desaturation may indicate the presence of a persistent left superior vena cava terminating in the left atrium. Moreover, an atrial septal defect identified surgically as lying in the postero-inferior angle of the atrial septum should suggest that an additional anomaly may be present in the form of termination of the left superior vena cava in the left atrium.

Comunicação interatrial do tipo seio coronário, comunicação interventricular e ausência de veia cava superior esquerda

“…A singularidade deste caso reside basicamente em três fatores: no diagnóstico da CIA tipo SC que por si só é uma cardiopatia congênita rara [1][2][3][4][5][6][7][8] ; na sua associação com outra cardiopatia não complexa como a CIV e na ausência da VCSE, o que também não é comum. Do ponto de vista embriológico, a CIA do tipo SC provavelmente decorre de uma septação incompleta da junção átrio venosa entre a veia cardinal esquerda e o AE 2 .…”

“…A CIA do tipo seio coronário (SC), também chamada de SC parcialmente ou totalmente sem teto, é uma doença rara [2][3][4][5][6][7][8] , resultante de uma incompleta formação da junção átrio venosa 2 . Geralmente está associada a cardiopatias congênitas complexas e persistência da veia cava superior esquerda (VCSE) [2][3][4][5][6][7] , sendo excepcional seu encontro com má formação isolada 4 . Neste artigo, descrevemos um caso de CIA do tipo SC associada a comunicação interventricular (CIV) perimembranosa e ausência de VCSE, sendo diagnosticada através da ecocardiografia e confirmada pela angiografia.…”

Partially unroofed coronary sinus and persistent left superior vena cava: intracardiac echocardiographic observation.

“…With the advent of echocardiography, it has become possible to diagnose this malformation before surgery.5-UJ A finding of dilated coronary sinus should alert the physician to consider the presence of an unusual drainage through the coronary sinus, either with a left-to-right shunt (partially unroofed coronary sinus, pulmonary venous connection to the coronary sinus, or coronary artery fistula) or without a left-to--right shunt (persistent left SVC, partial anomalous hepatic venous con· nection to the coronary sinus, or continuity of the inferior vena cava with the left SVC through the hemiazygos vein). 1 1 Although demonstration of a shunt from the left atrium to the coronary sinus by contrast5.i.li or color Dopplef'J.JO echocardiography will differentiate partially unroofed coronary sinus from other causes of dilated coronary sinus noted previ-J Ultrasound Med 15: [875][876][877][878][879]1996 ously, definitive diagnosis of unroofed coronary sinus depends on identification of a defect between the left atrium and the coronary sinus/>-lo However, its demonstration by transthoracic echocardiography may be difficult, 6 • 1 o and therefore the physician may have to rely on the transesophageal method.…”

Persistent left superior vena cava draining into the left atrium, atrial septal defect, and absence of the coronary sinus. Recognition and surgical correction.

“…The electrocardiogram is not likely to be helpful in identifying this complex, and is consistant with ASD, and/or other concomitant cardiac abnormalities.10), 11) The chest roentgenogram may show an unusually straight left heart and mediastinal borders.12)…”