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Persistent Left Superior Vena Cava Causing Subdivided Left Atrium: Diagnosis, Embryological Implications, and Surgical Management
Persistent Left Superior Vena Cava Causing Subdivided Left Atrium: Diagnosis, Embryological Implications, and Surgcal Management Robert J. Ascuitto, M.D., Ph.D., Nancy T. Ross-Ascuitto, M.D., Gary S. Kopf, M.D., John Fahey, M.D., Charles S. Kleinman, M.D., William E. Hellenbrand, M.D., and Norman S. Talner, M.D. ABSTRACT A 3-month-old infant is described in whom a
persistent left superior vena cava impinged on the posterior wall of the left atrium, producing a subdivided left atrium with left-to-right shunting and congestive heart failure. To our knowledge, this anomaly has not previously been reported. The preoperative diagnosis, surgical management, and embryological implications are discussed. Persistence of the left superior vena cava (LSVC) is a commonly described anomaly of the thoracic venous system [l]. In the vast majority of patients, the LSVC connects to the coronary sinus and thus drains into the right atrium [2]. Generally this anomaly has been considered clinically unimportant in the absence of additional congenital cardiac malformations [3]. This report describes an infant in whom a persistent LSVC and the dilated coronary sinus impinged on the posterior wall of the left atrium, such that the cavity of the left atrium was divided into two chambers. Each of these chambers communicated with the right atrium through an atrial septal defect. To our knowledge, this anomaly has not previously been reported. The preoperative evaluation using two-dimensional (2-D) echocardiography and the surgical procedure for relieving the left atrial obstruction are discussed. A 3-month-old male infant was admitted to Yale-New Haven Hospital because of respiratory distress and a heart murmur. Physical examination revealed a noncyanotic infant with wheezing and a respiration rate of 90 breathshin. Cardiac evaluation demonstrated a right ventricular heave, a grade 2/6 systolic ejection murmur loudest over the base of the heart, and a middiastolic rumble along the lower left sternal border. The electrocardiogram showed right-axis deviation and right ventricular hypertrophy. The chest roentgenogram showed cardiomegaly and pulmonary vascular markings compatible with increased pulmonary blood flow. A 2-D echocardiogram revealed marked dilatation of From the Section of Pediatric Cardiology and Cardiovascular Surgery, Yale University School of Medicine, New Haven, CT. Accepted for publication Feb 11, 1987. Address reprint requests to Dr.Kopf, Department of Surgery, Yale Medical School, 333 Cedar St, New Haven, CT 06510.
546 Ann Thorac Surg 44:546-549, Nov 1987
the right side of the heart and paradoxical ventricular septal motion. The left atrium was seen to be subdivided into two chambers by a structure that appeared to be a dilated, malpositioned coronary sinus (Fig 1A and B). An LSVC was demonstrated to be in continuity with this structure. The proximal chamber of the left atrium communicated with the right atrium through an atrial septal defect (see Fig 1A). Pulsed Doppler echocardiographic flow analysis showed left-to-right shunting across this defect. A second atrial septal defect allowed communication between the distal chamber of the left atrium and the right atrium (see Fig 1A). No specific shunting pattern was evident by Doppler echocardiographic analysis, although abnormal turbulent flow was demonstrated in the distal chamber. Only a narrow channel above the coronary sinus appeared to allow direct communication between the two chambers of the left atrium (see Fig 1B). The pulmonary veins appeared to enter normally into the left atrium. The patient underwent operation, without cardiac catheterization, with a diagnosis of left atrial obstruction and volume overload of the right side of the heart from left-to-right shunting across an atrial septal defect. Through a median sternotomy, the ascending aorta and superior and inferior venae cavae were cannulated, and the patient was placed on cardiopulmonary bypass. After aortic cross-clamping and administration of cardioplegic solution, the right atrium was opened with an oblique incision. Two atrial septal defects were seen communicating with the cavity of the left atrium, which was partitioned into two chambers by a prominent ridge of tissue coursing diagonally along the inner aspect of the posterior wall of the left atrium. Closer inspection revealed this ridge to be composed of a persistent LSVC connecting to a markedly dilated coronary sinus (Fig 2). The ostium of the coronary sinus emptied into the right atrium and was widely patent. One atrial septal defect communicated with the proximal chamber of the left atrium, into which all four pulmonary veins entered normally. The other atrial septal defect, identified as the fossa ovalis, communicated with the distal chamber, which contained the left atrial appendage and mitral valve. A narrow channel measuring approximately 2% mm in diameter, above the roof of the coronary sinus, allowed direct communication between the two chambers of the left atrium. This channel was bordered superiorly by the anterior wall of the left atrium, which was under tension from fibrous attachments to the lat-
517 Case Report: Ascuitto et a1 Persistent Left SVC Causing Subdivided LA
Preoperative
Postoperative
\
Fig 1. (A) Subcostal two-dimensional echocardiographic v i m showing a dilated coronary sinus ( CS) coursing along the posterior wall of the left atrium (LA) and emptying into a markedly dilated right atrium (a) There .is an atrial septal defect (ASD) proximal and distal to the CS. (B)Parasternal long-axis view, showing the dilated CS subdividing the cavity of the LA. (0Parasternal long-axis view, showing the enlarged communication between the proximal and distal chambers of the LA after surgical repair. (MV = mitral valve; TV = tricuspid valve; A 0 = ascending aorta; LV = left ventricle.)
with the suture line extending around the opening of the coronary sinus (see Fig 2). This maneuver relieved the tension on the anterior wall of the left atrium by dividing the fibrous attachments to the atrial septum, ensured a large communication between the proximal and distal chambers of the left atrium, and maintained the integrity of the coronary sinus (see Fig 1). The patient had an uneventful recovery.
Comment era1 wall of the left atrium and to the atrial septum around the coronary sinus. The intraatrial obstruction was relieved by extending the incision into the atrial septum between the proximal and distal atrial septal defects. A bovine pericardial patch was then used to reconstruct the atrial septum,
In our patient, the left atrium was subdivided by a persistent LSVC and dilated coronary sinus into a proximal (pulmonary venous) and distal (supramitral) chamber, resulting in a volume overload of the right side of the heart. These findings were suggested by the 2-D echocardiogram and confirmed at operation.
548 The Annals of Thoracic Surgery Vol 44 No 5 November 1987
L '
Fig 2 . Intraoperative view, showing the dilated, malpositioned coronary sinus (CS) subdividing the cavity of the left atrium (LA). The patch used to reconstruct the atrial septum is aIso shown in place. (RA = right atrium.)
It is intriguing to speculate whether this anomaly resulted from a developmental abnormality of the cardinal venous system. Normally, the left atrium begins separation from the systemic veins by an invagination between the left atrium and the left horn of the sinus venosus. Ultimately, a rightward shift of the sinus venoms completes the anatomical isolation of the left atrium from the systemic veins [4]. In the course of migration of the sinus venosus toward the right, a portion of the left anterior cardinal vein (LSVC) and left common cardinal vein are pulled adjacent to the posterior wall of the left atrium [5]. If these veins fail to undergo the normal obliterative process, it seems possible that they could become incorporated into, and thus progressively compress, the posterior wall of the developing left atrium. Recently, Gharagozloo and colleagues [6] demonstrated that, in some hearts with cor triatriatum, the
patch
I
fibromuscular membrane subdividing the left atrium was attached along the inner wall of the left atrium beneath the course followed by a persistent LSVC. These investigators postulated that this abnormal membrane may be induced by the LSVC impinging on the posterior wall of the primitive left atrium. In our patient, the left atrium was subdivided as in classic cor triatriatum, type Ab [ 7 ] . This anatomical arrangement is to be distinguished from a variant of supramitral stenosing ring, in which the fossa ovalis and left atrial appendage lie proximal to the intraatrial obstruction [8]. Based on the pathogenesis of cor triatriatum proposed by Gharagozloo and associates [6],our case may represent a forme fruste of cor triatriatum, in which a portion of the LSVC and the dilated coronary sinus subdivided the cavity of the left atrium rather than the usual fibromuscular membrane.
References 1. ShermanF E An Atlas of Congenital Heart Disease. Philadelphia, Lea & Febiger, 1963, p 72 2. Goor DA, Lillehei CW: Congenital Malformations of the Heart. New York, Grune & Stratton, 1975, p 398 3. Friedlick A, Bing RJ, Blount SG Jr, et al: Physiological studies
549 Case Report: Ascuitto et al: Persistent Left SVC Causing Subdivided LA
in congenital heart disease. Bull Johns Hopkins Hosp 8620, 1950 4. Raghib G, Ruttenberg HD, Anderson RC, et al: Termination of left superior vena cava in left atrium, atrial septa1 defects and absence of coronary sinus. Circulation 31:906, 1965 5. Corliss CE: Patten’s Human Embryology: Elements of Clinical Development. New York, McGraw-Hill, 1976, p 401 6. Gharagozloo F, Bulkley BH, Hutchings GM, et al: A pro-
posed pathogenesis of cor triatriatum: impingement of the left superior vena cava on the developing left atrium. Am Heart J 94:618, 1977 7. Thilenius OG, Bharati S, Lev J, et al: Subdivided left atrium: an expanded concept of cor triatriatum sinistrum. Am J Cardiol37743, 1976 8. Manubens R, Keovetz LJ, Adams P Jr, et al: Supravalvar stenosing ring of the left atrium. Am Heart J 60:286, 1960
REVIEW OF RECENT BOOKS
Thoracic Outlet Syndrome: Diagnosis and Treatment Edited by Erich W . Pollak Mount Kisco, Ny,Futura Publishing Co, 1986 232 pp, illustrated, $39.50 Reviewed by Richard G.Fosburg, M.D.
Dr.Pollak has provided us with an encyclopedic review of the topics related to the thoracic outlet syndrome. The book is well organized into twelve chapters, seven of which are authored by Dr. Pollak. Contributing authors describe the operative treatments that have been employed throughout the years. I found the book to be a scholarly treatise that presents a blend of visual aids by the artful use of illustrations, tables, photographs, artist’s drawings, and x-ray studies. The chapter on Neuroelectric Studies provides an expanded perception of where the diagnostic procedures now available have led us. The chapter on
Physical Treatment by John Redford is well illustrated and depicts the exercises in a clear and understandable manner. The book will have a limited audience but is certainly recommended for all individuals dealing with patients who have symptoms that fit into the complex of thoracic outlet syndrome. It should be in the libraries of all departments of surgery and accessible to those who encounter these patients. The editor has provided a text that accomplishes a complete historical review and provides the reader with a balanced discussion of the many procedures available, both for diagnosis and treatment. The k q u e n t use of tables throughout many of the chapters permits the reader to obtain a summary view. Dr.Pollak states that his book was written to review the present knowledge and to discuss the various management alternatives. He has achieved this most satisfactorily.
La Jolla, CA
persistent left superior vena cava impinged on the posterior wall of the left atrium, producing a subdivided left atrium with left-to-right shunting and congestive heart failure. To our knowledge, this anomaly has not previously been reported. The preoperative diagnosis, surgical management, and embryological implications are discussed. Persistence of the left superior vena cava (LSVC) is a commonly described anomaly of the thoracic venous system [l]. In the vast majority of patients, the LSVC connects to the coronary sinus and thus drains into the right atrium [2]. Generally this anomaly has been considered clinically unimportant in the absence of additional congenital cardiac malformations [3]. This report describes an infant in whom a persistent LSVC and the dilated coronary sinus impinged on the posterior wall of the left atrium, such that the cavity of the left atrium was divided into two chambers. Each of these chambers communicated with the right atrium through an atrial septal defect. To our knowledge, this anomaly has not previously been reported. The preoperative evaluation using two-dimensional (2-D) echocardiography and the surgical procedure for relieving the left atrial obstruction are discussed. A 3-month-old male infant was admitted to Yale-New Haven Hospital because of respiratory distress and a heart murmur. Physical examination revealed a noncyanotic infant with wheezing and a respiration rate of 90 breathshin. Cardiac evaluation demonstrated a right ventricular heave, a grade 2/6 systolic ejection murmur loudest over the base of the heart, and a middiastolic rumble along the lower left sternal border. The electrocardiogram showed right-axis deviation and right ventricular hypertrophy. The chest roentgenogram showed cardiomegaly and pulmonary vascular markings compatible with increased pulmonary blood flow. A 2-D echocardiogram revealed marked dilatation of From the Section of Pediatric Cardiology and Cardiovascular Surgery, Yale University School of Medicine, New Haven, CT. Accepted for publication Feb 11, 1987. Address reprint requests to Dr.Kopf, Department of Surgery, Yale Medical School, 333 Cedar St, New Haven, CT 06510.
546 Ann Thorac Surg 44:546-549, Nov 1987
the right side of the heart and paradoxical ventricular septal motion. The left atrium was seen to be subdivided into two chambers by a structure that appeared to be a dilated, malpositioned coronary sinus (Fig 1A and B). An LSVC was demonstrated to be in continuity with this structure. The proximal chamber of the left atrium communicated with the right atrium through an atrial septal defect (see Fig 1A). Pulsed Doppler echocardiographic flow analysis showed left-to-right shunting across this defect. A second atrial septal defect allowed communication between the distal chamber of the left atrium and the right atrium (see Fig 1A). No specific shunting pattern was evident by Doppler echocardiographic analysis, although abnormal turbulent flow was demonstrated in the distal chamber. Only a narrow channel above the coronary sinus appeared to allow direct communication between the two chambers of the left atrium (see Fig 1B). The pulmonary veins appeared to enter normally into the left atrium. The patient underwent operation, without cardiac catheterization, with a diagnosis of left atrial obstruction and volume overload of the right side of the heart from left-to-right shunting across an atrial septal defect. Through a median sternotomy, the ascending aorta and superior and inferior venae cavae were cannulated, and the patient was placed on cardiopulmonary bypass. After aortic cross-clamping and administration of cardioplegic solution, the right atrium was opened with an oblique incision. Two atrial septal defects were seen communicating with the cavity of the left atrium, which was partitioned into two chambers by a prominent ridge of tissue coursing diagonally along the inner aspect of the posterior wall of the left atrium. Closer inspection revealed this ridge to be composed of a persistent LSVC connecting to a markedly dilated coronary sinus (Fig 2). The ostium of the coronary sinus emptied into the right atrium and was widely patent. One atrial septal defect communicated with the proximal chamber of the left atrium, into which all four pulmonary veins entered normally. The other atrial septal defect, identified as the fossa ovalis, communicated with the distal chamber, which contained the left atrial appendage and mitral valve. A narrow channel measuring approximately 2% mm in diameter, above the roof of the coronary sinus, allowed direct communication between the two chambers of the left atrium. This channel was bordered superiorly by the anterior wall of the left atrium, which was under tension from fibrous attachments to the lat-
517 Case Report: Ascuitto et a1 Persistent Left SVC Causing Subdivided LA
Preoperative
Postoperative
\
Fig 1. (A) Subcostal two-dimensional echocardiographic v i m showing a dilated coronary sinus ( CS) coursing along the posterior wall of the left atrium (LA) and emptying into a markedly dilated right atrium (a) There .is an atrial septal defect (ASD) proximal and distal to the CS. (B)Parasternal long-axis view, showing the dilated CS subdividing the cavity of the LA. (0Parasternal long-axis view, showing the enlarged communication between the proximal and distal chambers of the LA after surgical repair. (MV = mitral valve; TV = tricuspid valve; A 0 = ascending aorta; LV = left ventricle.)
with the suture line extending around the opening of the coronary sinus (see Fig 2). This maneuver relieved the tension on the anterior wall of the left atrium by dividing the fibrous attachments to the atrial septum, ensured a large communication between the proximal and distal chambers of the left atrium, and maintained the integrity of the coronary sinus (see Fig 1). The patient had an uneventful recovery.
Comment era1 wall of the left atrium and to the atrial septum around the coronary sinus. The intraatrial obstruction was relieved by extending the incision into the atrial septum between the proximal and distal atrial septal defects. A bovine pericardial patch was then used to reconstruct the atrial septum,
In our patient, the left atrium was subdivided by a persistent LSVC and dilated coronary sinus into a proximal (pulmonary venous) and distal (supramitral) chamber, resulting in a volume overload of the right side of the heart. These findings were suggested by the 2-D echocardiogram and confirmed at operation.
548 The Annals of Thoracic Surgery Vol 44 No 5 November 1987
L '
Fig 2 . Intraoperative view, showing the dilated, malpositioned coronary sinus (CS) subdividing the cavity of the left atrium (LA). The patch used to reconstruct the atrial septum is aIso shown in place. (RA = right atrium.)
It is intriguing to speculate whether this anomaly resulted from a developmental abnormality of the cardinal venous system. Normally, the left atrium begins separation from the systemic veins by an invagination between the left atrium and the left horn of the sinus venosus. Ultimately, a rightward shift of the sinus venoms completes the anatomical isolation of the left atrium from the systemic veins [4]. In the course of migration of the sinus venosus toward the right, a portion of the left anterior cardinal vein (LSVC) and left common cardinal vein are pulled adjacent to the posterior wall of the left atrium [5]. If these veins fail to undergo the normal obliterative process, it seems possible that they could become incorporated into, and thus progressively compress, the posterior wall of the developing left atrium. Recently, Gharagozloo and colleagues [6] demonstrated that, in some hearts with cor triatriatum, the
patch
I
fibromuscular membrane subdividing the left atrium was attached along the inner wall of the left atrium beneath the course followed by a persistent LSVC. These investigators postulated that this abnormal membrane may be induced by the LSVC impinging on the posterior wall of the primitive left atrium. In our patient, the left atrium was subdivided as in classic cor triatriatum, type Ab [ 7 ] . This anatomical arrangement is to be distinguished from a variant of supramitral stenosing ring, in which the fossa ovalis and left atrial appendage lie proximal to the intraatrial obstruction [8]. Based on the pathogenesis of cor triatriatum proposed by Gharagozloo and associates [6],our case may represent a forme fruste of cor triatriatum, in which a portion of the LSVC and the dilated coronary sinus subdivided the cavity of the left atrium rather than the usual fibromuscular membrane.
References 1. ShermanF E An Atlas of Congenital Heart Disease. Philadelphia, Lea & Febiger, 1963, p 72 2. Goor DA, Lillehei CW: Congenital Malformations of the Heart. New York, Grune & Stratton, 1975, p 398 3. Friedlick A, Bing RJ, Blount SG Jr, et al: Physiological studies
549 Case Report: Ascuitto et al: Persistent Left SVC Causing Subdivided LA
in congenital heart disease. Bull Johns Hopkins Hosp 8620, 1950 4. Raghib G, Ruttenberg HD, Anderson RC, et al: Termination of left superior vena cava in left atrium, atrial septa1 defects and absence of coronary sinus. Circulation 31:906, 1965 5. Corliss CE: Patten’s Human Embryology: Elements of Clinical Development. New York, McGraw-Hill, 1976, p 401 6. Gharagozloo F, Bulkley BH, Hutchings GM, et al: A pro-
posed pathogenesis of cor triatriatum: impingement of the left superior vena cava on the developing left atrium. Am Heart J 94:618, 1977 7. Thilenius OG, Bharati S, Lev J, et al: Subdivided left atrium: an expanded concept of cor triatriatum sinistrum. Am J Cardiol37743, 1976 8. Manubens R, Keovetz LJ, Adams P Jr, et al: Supravalvar stenosing ring of the left atrium. Am Heart J 60:286, 1960
REVIEW OF RECENT BOOKS
Thoracic Outlet Syndrome: Diagnosis and Treatment Edited by Erich W . Pollak Mount Kisco, Ny,Futura Publishing Co, 1986 232 pp, illustrated, $39.50 Reviewed by Richard G.Fosburg, M.D.
Dr.Pollak has provided us with an encyclopedic review of the topics related to the thoracic outlet syndrome. The book is well organized into twelve chapters, seven of which are authored by Dr. Pollak. Contributing authors describe the operative treatments that have been employed throughout the years. I found the book to be a scholarly treatise that presents a blend of visual aids by the artful use of illustrations, tables, photographs, artist’s drawings, and x-ray studies. The chapter on Neuroelectric Studies provides an expanded perception of where the diagnostic procedures now available have led us. The chapter on
Physical Treatment by John Redford is well illustrated and depicts the exercises in a clear and understandable manner. The book will have a limited audience but is certainly recommended for all individuals dealing with patients who have symptoms that fit into the complex of thoracic outlet syndrome. It should be in the libraries of all departments of surgery and accessible to those who encounter these patients. The editor has provided a text that accomplishes a complete historical review and provides the reader with a balanced discussion of the many procedures available, both for diagnosis and treatment. The k q u e n t use of tables throughout many of the chapters permits the reader to obtain a summary view. Dr.Pollak states that his book was written to review the present knowledge and to discuss the various management alternatives. He has achieved this most satisfactorily.
La Jolla, CA