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A rare case of inferior venacaval type of atrial septal defect in an adult: Echocardiographic features
A Rare Case of Inferior Venacaval Type of Atrial Septal Defect in an Adult: Echocardiographic Features Ramdas G. Pai, MD, FRCP(E), Sudha M. Pai, MD, Vickie Ortega, RDCS, and Angle Lopez,
Loma Linda, California
We r e p o r t a rare type o f atrial septal defect with communication between the left atrium and the inferior vena cava. This type o f defect has been referred to as a low sinus venosus type o f atrial septal defect because o f its developmental origin, and possibly is caused by
Atrial septal
defects (ASDs) generally are divided into defects o f the o s t i u m s e c u n d u m , o s t i u m prim u m , a n d the sinus venosus. 1-3 A p p r o x i m a t e l y 80% o f A S D s o c c u r in the r e g i o n o f the fossa ovalis a n d d o n o t e x t e n d to involve thc inferior vena cava. A single case has b e e n r e p o r t e d o f a small, h e m o d y n a m i c a l l y insignificant A S D c o n n e c t i n g to the inferior vena cava a n d associated w i t h mitral stenosis. 4 W e r e p o r t a case o f a h e m o d y n a m i c a l l y significant inferior type o f sinus venosus A S D localizcd to the p a r t o f t h e atrial s e p t u m t h a t separates t h e left a t r i u m f r o m t h e inferior vena cava. D e t a i l e d c c h o c a r d i o g r a p h i c featurcs are discussed. CASE R E P O R T
A 65-year-old man was seen because o f mild exertional dyspnea. A physical cxamination revealed normal cardiac size, normal heart sounds with normal mobility of the components o f the second heart sound, and a 2/6 ejection systolic murmur at the left sternal border. No ejection click was observed. The findings o f a chest roentgenograph were interpreted as normal. The results o f thc electrocardiogram were within normal limits. A transthoracic echocardiogram showed mild dilation of the right-sided chambers. A subcostal examination showed a defect in the inferoposterior portion o f the atrial septum with a communication between the left atrium and the inferior vena cava. A transesophageal examination confirmed the presence of the defect location (Figure 1). The defect measured 1.0 by 1.2 cm in diameter. An agitated normal saline solution
From the Section of Cardiology, Jerry L. Petfis VA Medical Center and Loma Linda University, Loma Linda. Reprint requests: Ramdas G. Pai, MD, FRCP(E), Cardiology ( l l l C ) , Jerry L. Pettis VA Hospital, 11201 Benton St., Loma Linda, CA 92357. Copyright © 1996 by the American Society of Echocardiography. 0894-7317/96 $5.00 + 0 2 7 / 4 / 7 1 0 3 2
defective absorption o f the left venous valve o f the sinus venosus into the septum secundum. Detailed echocardiographic features are discussed. (J Am Soc Eehocardiogr 1996;9:819-21.)
injected into the arm vein showed a negative contrast effect on the venacaval side of the defect (Figure 2). Color flow imaging showed an abnormal left to right flow across the defect (Figure 3). Spectral Doppler imaging showed a prominent systolic-diastolicflow into the inferior vena cava from the left atrium characteristic of flow across an ASD. Cardiac catheterization showed step-up in the oxygen saturation in the upper inferior vena cava and a shunt run showed a pulmonary to systemic flow ratio of 1.7. DISCUSSION
An inferior venacaval type of ASD is rare and, to our knowledge, only one case of this type o f defect has been reported. 4 Ricou et al.4 reported that in that patient the shunt was too small to be detected during cardiac catheterization and could have been a stretched foramen ovale caused by moderate mitral stenosis. In the presence of mitral stenosis, the left to right shunt increases because of elevated left atrial pressure. A m o n g t h e 154 patients with secundum ASD reported by Shubs et al., no patient was noted to have a defect communicating with the inferior vena cava. 1 Mehra et al. 2 described the echocardiographic features of 50 patients with different types of ASD, but none of these patients had an inferior venacaval type o f defect. Our patient clearly had a significant shunt into the inferior vena cava in the absence ofmitral valvular disease. Furthermore, the defect was clearly inferior to the eustachian valve and was not caused by stretching o f the foramen ovale. All the pulmonary veins in this patient drained into the left atrium. The defect in our patient was classified as a low type of sinus venosus ASD in view o f its developmental origin. ~ The opening of the inferior vena cava originates from the sinus venosus, which also gives rise to the juxtacardiac portions o f the superior vena cava and the coronary sinus. 6 During the development o f the right atrium, the opening of the sinus venosus into the right atrium is guarded by left and right venous valves. The left venous valve is absorbed into the septum secundum and the right valve forms valves of the inferior vena cava and the coronary sinus. Thus the 819
820
Pai et al.
F i g u r e 1 Transesophageal four-chamber view showing the location of the atrial septal defect (ASD) in the inferior vena cava (IVC). (AO,Aorta; EV, Eustachian valve; LA, left atrium; RA, right atrium; RPA,right pulmonary artery.)
Journal of the AmericanSocietyOf Echocardiography November-December 1996
F i g u r e 2 Negative contrast effect in the IVC caused by shunt flow from the LA at this level. Image orientation and abbreviations as in Figure 1.
F i g u r e 3 Color flow imaging from the transesophageal approach showing left to right shunt across the ASD. Abbreviations as in Figure 1.
Journal of the American Societyof Echocardiography Volume 9 Number 6
inferior venacaval type o f ASD is likely to bc causcd by dcfectivc incorporation o f the left venous valve into the septum secundum. In summary, we present detailed cchocardiographic features o f an unusual type o f ASD communicating with the inferior vena cava. REFERENCES
1. Shub C, Dimopoulos I, Seward J, et al. Sensitivity of two dimensional echocardiography in the direct visualization of atrial septal defect utilizing the subcostal approach. J Am Coll Cardioi 1983;2:127-35.
Pai et al.
821
2. Mehra R, Hdmcke F, Nanda N, Pinheiro L, Samdarshi T, Shah V. Use and limitations oftransthoracic echocardiograptly in the assessment of atrial septal defect in the adults. Am J Cardiol 1991;67:28&94. 3. Mehra R, Helmcke F, Nanda N, Hsiung M, Pacifico A, Hsu T. Transesophageal Doppler color flow mapping assessment of an'ial septal defect. J Am Coil Cardiol 1990;16:1010-6. 4. Ricou FJ, Reynard CA, Lerch R. Transesophageal echocardiography in the diagnosis of inferior caval secundum atrial septal defect:Am Heaa't J 1994;128:196-9. 5. Buyse ML. Birth Defects Encyclopedia. 1st ed. Dover, MA: Center For Birth Defects Information Services 1990:209. 6. Clemente CD. Gray's Anatomy. 30th ed. Philadelphia: Lea & Febiger, 1985:612.
Loma Linda, California
We r e p o r t a rare type o f atrial septal defect with communication between the left atrium and the inferior vena cava. This type o f defect has been referred to as a low sinus venosus type o f atrial septal defect because o f its developmental origin, and possibly is caused by
Atrial septal
defects (ASDs) generally are divided into defects o f the o s t i u m s e c u n d u m , o s t i u m prim u m , a n d the sinus venosus. 1-3 A p p r o x i m a t e l y 80% o f A S D s o c c u r in the r e g i o n o f the fossa ovalis a n d d o n o t e x t e n d to involve thc inferior vena cava. A single case has b e e n r e p o r t e d o f a small, h e m o d y n a m i c a l l y insignificant A S D c o n n e c t i n g to the inferior vena cava a n d associated w i t h mitral stenosis. 4 W e r e p o r t a case o f a h e m o d y n a m i c a l l y significant inferior type o f sinus venosus A S D localizcd to the p a r t o f t h e atrial s e p t u m t h a t separates t h e left a t r i u m f r o m t h e inferior vena cava. D e t a i l e d c c h o c a r d i o g r a p h i c featurcs are discussed. CASE R E P O R T
A 65-year-old man was seen because o f mild exertional dyspnea. A physical cxamination revealed normal cardiac size, normal heart sounds with normal mobility of the components o f the second heart sound, and a 2/6 ejection systolic murmur at the left sternal border. No ejection click was observed. The findings o f a chest roentgenograph were interpreted as normal. The results o f thc electrocardiogram were within normal limits. A transthoracic echocardiogram showed mild dilation of the right-sided chambers. A subcostal examination showed a defect in the inferoposterior portion o f the atrial septum with a communication between the left atrium and the inferior vena cava. A transesophageal examination confirmed the presence of the defect location (Figure 1). The defect measured 1.0 by 1.2 cm in diameter. An agitated normal saline solution
From the Section of Cardiology, Jerry L. Petfis VA Medical Center and Loma Linda University, Loma Linda. Reprint requests: Ramdas G. Pai, MD, FRCP(E), Cardiology ( l l l C ) , Jerry L. Pettis VA Hospital, 11201 Benton St., Loma Linda, CA 92357. Copyright © 1996 by the American Society of Echocardiography. 0894-7317/96 $5.00 + 0 2 7 / 4 / 7 1 0 3 2
defective absorption o f the left venous valve o f the sinus venosus into the septum secundum. Detailed echocardiographic features are discussed. (J Am Soc Eehocardiogr 1996;9:819-21.)
injected into the arm vein showed a negative contrast effect on the venacaval side of the defect (Figure 2). Color flow imaging showed an abnormal left to right flow across the defect (Figure 3). Spectral Doppler imaging showed a prominent systolic-diastolicflow into the inferior vena cava from the left atrium characteristic of flow across an ASD. Cardiac catheterization showed step-up in the oxygen saturation in the upper inferior vena cava and a shunt run showed a pulmonary to systemic flow ratio of 1.7. DISCUSSION
An inferior venacaval type of ASD is rare and, to our knowledge, only one case of this type o f defect has been reported. 4 Ricou et al.4 reported that in that patient the shunt was too small to be detected during cardiac catheterization and could have been a stretched foramen ovale caused by moderate mitral stenosis. In the presence of mitral stenosis, the left to right shunt increases because of elevated left atrial pressure. A m o n g t h e 154 patients with secundum ASD reported by Shubs et al., no patient was noted to have a defect communicating with the inferior vena cava. 1 Mehra et al. 2 described the echocardiographic features of 50 patients with different types of ASD, but none of these patients had an inferior venacaval type o f defect. Our patient clearly had a significant shunt into the inferior vena cava in the absence ofmitral valvular disease. Furthermore, the defect was clearly inferior to the eustachian valve and was not caused by stretching o f the foramen ovale. All the pulmonary veins in this patient drained into the left atrium. The defect in our patient was classified as a low type of sinus venosus ASD in view o f its developmental origin. ~ The opening of the inferior vena cava originates from the sinus venosus, which also gives rise to the juxtacardiac portions o f the superior vena cava and the coronary sinus. 6 During the development o f the right atrium, the opening of the sinus venosus into the right atrium is guarded by left and right venous valves. The left venous valve is absorbed into the septum secundum and the right valve forms valves of the inferior vena cava and the coronary sinus. Thus the 819
820
Pai et al.
F i g u r e 1 Transesophageal four-chamber view showing the location of the atrial septal defect (ASD) in the inferior vena cava (IVC). (AO,Aorta; EV, Eustachian valve; LA, left atrium; RA, right atrium; RPA,right pulmonary artery.)
Journal of the AmericanSocietyOf Echocardiography November-December 1996
F i g u r e 2 Negative contrast effect in the IVC caused by shunt flow from the LA at this level. Image orientation and abbreviations as in Figure 1.
F i g u r e 3 Color flow imaging from the transesophageal approach showing left to right shunt across the ASD. Abbreviations as in Figure 1.
Journal of the American Societyof Echocardiography Volume 9 Number 6
inferior venacaval type o f ASD is likely to bc causcd by dcfectivc incorporation o f the left venous valve into the septum secundum. In summary, we present detailed cchocardiographic features o f an unusual type o f ASD communicating with the inferior vena cava. REFERENCES
1. Shub C, Dimopoulos I, Seward J, et al. Sensitivity of two dimensional echocardiography in the direct visualization of atrial septal defect utilizing the subcostal approach. J Am Coll Cardioi 1983;2:127-35.
Pai et al.
821
2. Mehra R, Hdmcke F, Nanda N, Pinheiro L, Samdarshi T, Shah V. Use and limitations oftransthoracic echocardiograptly in the assessment of atrial septal defect in the adults. Am J Cardiol 1991;67:28&94. 3. Mehra R, Helmcke F, Nanda N, Hsiung M, Pacifico A, Hsu T. Transesophageal Doppler color flow mapping assessment of an'ial septal defect. J Am Coil Cardiol 1990;16:1010-6. 4. Ricou FJ, Reynard CA, Lerch R. Transesophageal echocardiography in the diagnosis of inferior caval secundum atrial septal defect:Am Heaa't J 1994;128:196-9. 5. Buyse ML. Birth Defects Encyclopedia. 1st ed. Dover, MA: Center For Birth Defects Information Services 1990:209. 6. Clemente CD. Gray's Anatomy. 30th ed. Philadelphia: Lea & Febiger, 1985:612.