CASE REPORTS
Cor Triatriatum Dexter: Transesophageal Echocardiographic Diagnosis and 3-Dimensional Reconstruction Francisco-Javier Roldán, MD, Jesús Vargas-Barrón, MD, Nilda Espinola-Zavaleta, MD, Angel Romero-Cárdenas, MD, Candace Keirns, MD, Clara Vázquez-Antona, MD, and Jose-Pablo Hernandez, MD, Tlalpan, Mexico
Cor triatriatum dexter is an unusual cardiac abnormality with division between the sinus and primitive atrial portions of the right atrium. Three-
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he persistence of the right valve of the sinus venosus in the embryonic heart produces a spectrum of abnormalities that include a membranous remnant of the crista terminalis, the Chiari network, and cor triatriatum dexter. In this last anomaly, the entire right valve remains and originates a division between the sinus and primitive atrial portions of the right atrium.1 This anomaly is frequently associated with severe malformations of the other right heart structures; right heart chamber hypoplasia is the most common association.2 Until a few years ago, the diagnosis of cor triatriatum dexter was established only at autopsy; today echocardiography is the method of choice for its identification.The following report will describe the findings in an adult patient in whom the presence of a cor triatriatum dexter was suspected after transthoracic echocardiography. The diagnosis was confirmed with a transesophageal study, and the anatomic characteristics of the embryonic remnant were determined with precision by means of 3dimensional reconstruction.
dimensional echocardiography is a novel technique that defines this entity. (J Am Soc Echocardiogr 2001; 14:634-6.)
14.When he was 38 years old, he underwent replacement of both valves with mechanical prostheses. The surgical approach was through the left atrium, and no incidents
CASE REPORT A 39-year-old man with history of rheumatic fever had aortic regurgitation and mitral stenosis detected at the age of From Instituto Nacional de Cardiología Ignacio Chávez and Instituto Nacional de la Nutrición (C.K.) Salvador Zubirán. Reprint requests: Jesús Vargas-Barrón, MD, Department of Echocardiography, Instituto Nacional de Cardiología Ignacio Chávez, Juan Badiano No. 1, Tlalpan, 14080 México, DF, Mexico (E-mail:
[email protected]). Copyright © 2001 by the American Society of Echocardiography. 0894-7317/2001/$35.00 + 0 27/4/110787 doi:10.1067/mje.2001.110787
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Figure 1 Apical 4-chamber image. Anomalous band in right atrium (RA) is seen as nodule (arrows). RV, Right ventricle; LV, left ventricle; LA, left atrium.
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Figure 3 Three-dimensional image shows right atrium (RA) divided by band (arrow) that extends from superior vena cava (SVC) to atrial floor. RV, Right ventricle; TV, tricuspid valve; IVC, inferior vena cava.
Figure 2 Transesophageal images in right atrial transverse (A) and longitudinal (B) planes. Arrows point to nonobstructive septation of right atrium (RA) by band. LA, Left atrium; Ao, aortic valve prosthesis; SVC, superior vena cava.
venosus.To confirm the diagnosis, a 3D reconstruction was created with the Echo-scan version 4.0 system from TomTec Gmb H (Munich, Germany). A sagittal section of the right atrium at the level of the inflow of the venae cavae was selected and laterally displaced toward the interatrial septum to include the embryonic structure completely.When the 3D reconstruction was completed, it was possible to determine that the cephalic portion of the band had developed along the crista terminalis and extended through the chamber to the floor of the right atrium above the tricuspid valve near the inferior vena cava.The two atrial segments communicated amply along the band. The band had no adhesions to other structures and had a small nodule in its middle third (Figure 3).
occurred during cannulation of the venae cavae. At the time of study, he was asymptomatic. Echocardiographic Studies Transthoracic study before surgery demonstrated the valve lesions.The apical 4-chamber image revealed a small, immobile, nodular image with slightly increased acoustic density in the right atrium.This image was believed to correspond to a prominence of the crista terminalis (Figure 1). Doppler analysis showed no alterations in right atrial flow. One year after surgery, dysfunction of the prosthetic valve in mitral position was suspected. A transesophageal echocardiogram was performed, and mild regurgitation of the prosthesis was found, with normal function of the aortic prosthesis. A band 28 mm long was identified in the right atrium.This band divided the chamber into two compartments, one superomedial and the other inferolateral (Figure 2). Doppler analysis corroborated absence of obstruction in right atrial flow. These findings were compatible with persistence of the right valve of the sinus
DISCUSSION At the third month of embryonic life, the right valve of the sinus venosus divides the right atrium almost completely into 2 chambers. The sinus portion receives the venae cavae and coronary sinus, and the primitive atrial portion, which is muscular, is associated with the tricuspid valve and includes the right atrial appendage. The embryonic structure undergoes involution between the 9th and 15th weeks of gestation, and its remnants persist as the Eustachian and Thebesian valves, related to the orifices of the inferior vena cava and the coronary sinus. The right valve of the sinus venosus divides the right atrium almost completely. Its persistence can vary from a small atrial septation by a membranous remnant of the Eustachian valve, an area of interconnected trabeculae corresponding to the Chiari net-
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work or, as in this case, a complete septation of the right atrium, or cor triatriatum dexter.3 This condition is unrelated to cor triatriatum sinister, in which failure of resorption of the common pulmonary veins results in a left atrium divided by a fibromuscular diaphragm. Failure of the venous valves to regress appropriately may create an abnormal fetal circulation that predispose severe malformations of the other right heart structures such as tricuspid atresia.4 The persistence of remnants of the right valve of the sinus venosus in adulthood has clinical relevance. It has been associated with catheter entrapment, supraventricular arrhythmias,5 and arterial embolic events.6 Noninvasive diagnosis of the persistence of the right valve of sinus venosus can have limitations when only chest wall images are used.Transesophageal echocardiography defines the characteristics of different embryonic remnants with precision and is useful in differentiating them from thrombi or intracardiac tumors.7,8 The incorporation of 3D reconstruction in echocardiographic images offers unanticipated aspects of interest. The first utility of this new technique was the clear definition of the anatomic characteristics of the band dividing the right atrium. Considering the wide spectrum of the embryonic vestiges in the right atrium and their association with complex congenital heart disease, it is probable that in the future, 3D reconstruction of transesophageal images complemented with Doppler analysis will be the technique of choice for studying these patients.
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Likewise, 3D echocardiography may represent an excellent method for teaching the pathologic anatomy of diverse complex congenital anomalies, particularly now that patients undergo surgical correction of their malformations at very early ages, limiting the study of anatomic specimens.
REFERENCES 1. Muñoz Castellanos L, Kuri M, García F, et al. Derivados patológicos de la valva derecha del seno venoso: Presentación de seis corazones de tipo cor triatriatum dextrum. Arch Inst Cardiol Mex 1998;58:53-6. 2. Moreno Granado F, Herrainz Sarachaga I, Castro Gussoni C, et al. Remnants of the embryologic sinus venosus valves: “Cor triatriatum dexter.” An Esp Pediatr 1976;9:407-14. 3. Ducharme A, Tardif JC, Mercier LA, et al. Remnants of the right valve of the sinus venosus presenting as a right atrial mass on transthoracic echocardiography. Can J Cardiol 1997; 13:573-6. 4. Bharati S, Mc Allister HA, Tatooles CJ, et al. Anatomic variations in underdevelopment right ventricle related to tricuspid atresia and stenosis. J Thorac Cardiovasc Surg 1976;72: 383-400. 5. Ott DA, Cooley DA, Angelini P, et al. Successful surgical correction of symptomatic cor triatriatum dexter. J Thorac Cardiovasc Surg 1979;78:573-5. 6. Scheider B, Hofmann T, Justen MH, et al. Chiari’s network: normal anatomic variant or risk factor for arterial embolic events? J Am Coll Cardiol 1995;26:203-10. 7. Battle-Díaz J, Stanley P, Kratz C, et al. Echocardiographic manifestation of persistence of the right sinus venous as valve. Am J Cardiol 1979;43:850-3. 8. Savas V, Samyn J, Schreiber TL, et al. Cor triatriatum dexter: recognition and percutaneous transluminal correction. Cathet Cardiovasc Diagn 1991;23:183-6.
