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Inverted left atrial appendage presenting as an unusual left atrial mass
CASE REPORTS
Inverted Left Atrial Appendage Presenting as an Unusual Left Atrial Mass L. LuAnn Minich, MD, John A. Hawkins, MD, Lloyd Y. Tani, MD, Victoria E. Judd, MD, and Edwin C. McGough, MD, Salt Lake City, Utah
A n unusual left atrial mass in an infant after repair o f truncus arteriosus was imaged by transthoracic and transesophageal echocardiography. The mass was identified as an inverted left atrial appendage, and the patient underwent uncomplicated surgical eversion. Unnecessary anticoagulation was avoided. (J AM Sor ECHOC~a~DIOGR 1995;8:328-30.)
]L ransesophageal echocardiography has an increasing role in the postoperative evaluation o f infants in the intensive care unit. 1'2 W e used this approach to clarify the diagnosis o f a n e w left atrial mass discovered after repair o f trtmcus arteriosus.
From the Departments of Pediatrics and Surgery, Primary Children's Medical Center and the University of Utah. Reprint requests: L. LuAnn Minich, MD, Primary Children's Medical Center, 100 N. Medical Dr., Salt Lake City, UT 84113. Copyright 9 1995 by the American Society of Echocardiography. 0894-7317/95 $3.00 + 0 27/4/58734
CASE R E P O R T
A 5-month-old, 4 kg infant was seen with a murmur and symptoms of congestive heart failure. Her cardiac examination revealed a constant systolic ejection click, grade I I I / V I systolic ejection murmur along the left sternal border, and a diastolic rumble at the apex. The transthoracic echocardiogram demonstrated type I truncus arteriosus with a trileaflet truncal valve that was not stenotic and very mildly regurgitant. She underwent routine surgical repair with patch closure of the ventricular septal defect and placement of a 14 mm homograft conduit from the right ventricle to the branch pulmonary arteries. 3 She was taken to the intensive care unit and supported hemodynamically with inotropes and afterload reduction. Because o f a sud-
Figure 1 Transthoracic apical four-chamber view with arrows demonstrates large left atrial mass. LA, Left atrium; LV, left ventricle; RA, right atrium; RV, right ventricle. 328
Journal of the AmericanSocietyof Echocardiography Volume 8 Number 3
Minich et al. 329
Figure 2 Transesophageal transverse view demonstrates left atrial mass and its relationship to mitral anulus and left pulmonary vein (LPV). Note absence of normal left atrial appendage. MV, Mitral valve.
den drop in systemic arterial saturation and poor perfusion approximately 36 hours after surgery, she underwent repeat transthoradc echocardiography. The study revealed acceptable estimates of pulmonary artery pressures and ventricular ejection, as well as no significant residual atrial or ventricular shunts. In addition, however, an unexpected 7 • 13 mm mass was identified in the left atrium. It appeared to be attached to the left lateral wall above the mitral anulus unassociated with the left atrial catheter (Figure 1). The mass was mobile and prolapsed into the mitral inflow funnel. Initially, this was thought to be a clot extending from the left atrial appendage, but with further discussion the possibility of an inverted left atrial appendage was entertained. As a result, transesophageal echocardiography was performed to aid in the differential diagnosis. The mass was well imaged from both transverse and longitudinal planes. In the transverse plane, its attachment was seen superior to the mitral anulus and inferior to the left pulmonary vein (Figure 2). The left atrial appendage, normally well seen from this view, was absent. ~ The longitudinal plane provided a better view of the broad base of the thumblike mass with its hinge-type motion and confirmed the absence of the normal left atrial appendage leading to the diagnosis of an inverted atrial appendage (Figure 3). Because of concerns regarding incarceration of the appendage, as well as its interference with ventricular filling, the patient was taken back to the operating room. The left
atrium was opened and a firm, purplish, trabeculated structure was identified as the incarcerated left atrial appendage. It could not be everted by pushing on it from the inside of the left atrium and required outside reduction with a right-angle clamp. It tended to reinvert, however, so it was surgically ligated at its base. The infant has recovered without sequelae.
DISCUSSION In this infant after surgery, transthoracic imaging s h o w e d a left atrial mass, but resolution o f its attachments and surrounding structures was limited by a paucity o f available i m a g i n g windows. T h e transesophageal approach n o t only allowed detailed imaging o f the characteristics and m o t i o n o f the mass but also p r o v i d e d information regarding its relationship to n o r m a l cardiac structures. T h e absence o f the left atrial appendage, which is usually well seen f r o m b o t h transverse and longitudinal views, 4,s helped confirm the diagnosis o f an inverted left atrial appendage. T h e left atrial appendage m a y have inverted f r o m the negative pressure that developed during placement o f the left atrial vent catheter. It is also possible that
330
Journal of the AmericanSocietyof Echocardiography May-June 1995
Minich et al.
F i g u r e 3 Transesophageal longitudinal view demonstrates broad base and thumblike appearance o f left atrial mass (arrow) and notable absence o f normal left atrial appendage. LA, Left atrium; LV, left ventricle.
the appendge failed to evert after it was inverted as part of the routine deairing procedure before discontinuing cardiopulmonary bypass. Aronson et al. 6 reported an inverted left atrial appendage in an adult after thrombectomy and postulated that the narrow base of the left atrial appendage prevented its spontaneous eversion. This infant's left atrial appendage was also noted to be long and narrow with a tendency to reinvert, leading to its surgical ligation. Little is known regarding the natural history of an inverted left atrial appendage. Danford et al. 7 reported subsequent reduction after it was identified in three patients but do not specify the indications for this. The decision for surgical eversion in this patient was based on concerns of incarceration and interference of left ventricular filling from the large atrial mass. In summary, transesophageal echocardiography provided imaging superior to transthoracic imaging and allowed diagnosis of an unusual left atrial mass as an inverted atrial appendage. The condition was corrected surgically and unnecessary anticoagulation was avoided. However, diagnosis by routine intraoperative transesophageal echocardiography allowing immediate correction would have prevented reoperation.
REFERENCES
1. Ritter SB. Transesophageal real-time echocardiography in infants and children with congenital heart disease. J Am CoU Cardiol 1991;18:569-80. 2. Wolfe LT, Rossi A, Ritter SB. Transesophageal echocardiography in infants and children: use and importance in the cardiac intensive care unit. I Am Soc Echocardiogr 1993; 6:286-9. 3. Bove EL, Lupinetti FM, Pridjian AK, et al. Results of a policy of primary repair oftruncus arteriosus in the neonate. J Thorac Cardiovasc Surg 1993;105:1057-66. 4. Seward JB, Khandheria BK, Oh JK, et al. Transesophaeai echocardiography: technique, anatomic correlations, implementation, and clinical applications. Mayo Clin Proc 1988;63:64980. 5. Seward JB, Khandheria BK, Edwards WD, Oh JK, Freeman WK, Tajik AJ. Biplanar transesophageal echocardiography: anatomic correlations, image orientation, and clinical applications. Mayo Clin Proc 1990;65:1193-213. 6. Aronson S, Ruo W, Sand M. Inverted left atrial appendage appearing as a left atrial mass with transesophageal echocardiography during cardiac surgery. Anesthesiology 1992;76: 1054-5. 7. Danford DA, Cheatham JP, Van Gundy JC, Mohiuddin SM, Fleming WH. Inversion of the left atrial appendage: clinical and echocardiographic correlates. Am Heart J 1994;127:71921.
Inverted Left Atrial Appendage Presenting as an Unusual Left Atrial Mass L. LuAnn Minich, MD, John A. Hawkins, MD, Lloyd Y. Tani, MD, Victoria E. Judd, MD, and Edwin C. McGough, MD, Salt Lake City, Utah
A n unusual left atrial mass in an infant after repair o f truncus arteriosus was imaged by transthoracic and transesophageal echocardiography. The mass was identified as an inverted left atrial appendage, and the patient underwent uncomplicated surgical eversion. Unnecessary anticoagulation was avoided. (J AM Sor ECHOC~a~DIOGR 1995;8:328-30.)
]L ransesophageal echocardiography has an increasing role in the postoperative evaluation o f infants in the intensive care unit. 1'2 W e used this approach to clarify the diagnosis o f a n e w left atrial mass discovered after repair o f trtmcus arteriosus.
From the Departments of Pediatrics and Surgery, Primary Children's Medical Center and the University of Utah. Reprint requests: L. LuAnn Minich, MD, Primary Children's Medical Center, 100 N. Medical Dr., Salt Lake City, UT 84113. Copyright 9 1995 by the American Society of Echocardiography. 0894-7317/95 $3.00 + 0 27/4/58734
CASE R E P O R T
A 5-month-old, 4 kg infant was seen with a murmur and symptoms of congestive heart failure. Her cardiac examination revealed a constant systolic ejection click, grade I I I / V I systolic ejection murmur along the left sternal border, and a diastolic rumble at the apex. The transthoracic echocardiogram demonstrated type I truncus arteriosus with a trileaflet truncal valve that was not stenotic and very mildly regurgitant. She underwent routine surgical repair with patch closure of the ventricular septal defect and placement of a 14 mm homograft conduit from the right ventricle to the branch pulmonary arteries. 3 She was taken to the intensive care unit and supported hemodynamically with inotropes and afterload reduction. Because o f a sud-
Figure 1 Transthoracic apical four-chamber view with arrows demonstrates large left atrial mass. LA, Left atrium; LV, left ventricle; RA, right atrium; RV, right ventricle. 328
Journal of the AmericanSocietyof Echocardiography Volume 8 Number 3
Minich et al. 329
Figure 2 Transesophageal transverse view demonstrates left atrial mass and its relationship to mitral anulus and left pulmonary vein (LPV). Note absence of normal left atrial appendage. MV, Mitral valve.
den drop in systemic arterial saturation and poor perfusion approximately 36 hours after surgery, she underwent repeat transthoradc echocardiography. The study revealed acceptable estimates of pulmonary artery pressures and ventricular ejection, as well as no significant residual atrial or ventricular shunts. In addition, however, an unexpected 7 • 13 mm mass was identified in the left atrium. It appeared to be attached to the left lateral wall above the mitral anulus unassociated with the left atrial catheter (Figure 1). The mass was mobile and prolapsed into the mitral inflow funnel. Initially, this was thought to be a clot extending from the left atrial appendage, but with further discussion the possibility of an inverted left atrial appendage was entertained. As a result, transesophageal echocardiography was performed to aid in the differential diagnosis. The mass was well imaged from both transverse and longitudinal planes. In the transverse plane, its attachment was seen superior to the mitral anulus and inferior to the left pulmonary vein (Figure 2). The left atrial appendage, normally well seen from this view, was absent. ~ The longitudinal plane provided a better view of the broad base of the thumblike mass with its hinge-type motion and confirmed the absence of the normal left atrial appendage leading to the diagnosis of an inverted atrial appendage (Figure 3). Because of concerns regarding incarceration of the appendage, as well as its interference with ventricular filling, the patient was taken back to the operating room. The left
atrium was opened and a firm, purplish, trabeculated structure was identified as the incarcerated left atrial appendage. It could not be everted by pushing on it from the inside of the left atrium and required outside reduction with a right-angle clamp. It tended to reinvert, however, so it was surgically ligated at its base. The infant has recovered without sequelae.
DISCUSSION In this infant after surgery, transthoracic imaging s h o w e d a left atrial mass, but resolution o f its attachments and surrounding structures was limited by a paucity o f available i m a g i n g windows. T h e transesophageal approach n o t only allowed detailed imaging o f the characteristics and m o t i o n o f the mass but also p r o v i d e d information regarding its relationship to n o r m a l cardiac structures. T h e absence o f the left atrial appendage, which is usually well seen f r o m b o t h transverse and longitudinal views, 4,s helped confirm the diagnosis o f an inverted left atrial appendage. T h e left atrial appendage m a y have inverted f r o m the negative pressure that developed during placement o f the left atrial vent catheter. It is also possible that
330
Journal of the AmericanSocietyof Echocardiography May-June 1995
Minich et al.
F i g u r e 3 Transesophageal longitudinal view demonstrates broad base and thumblike appearance o f left atrial mass (arrow) and notable absence o f normal left atrial appendage. LA, Left atrium; LV, left ventricle.
the appendge failed to evert after it was inverted as part of the routine deairing procedure before discontinuing cardiopulmonary bypass. Aronson et al. 6 reported an inverted left atrial appendage in an adult after thrombectomy and postulated that the narrow base of the left atrial appendage prevented its spontaneous eversion. This infant's left atrial appendage was also noted to be long and narrow with a tendency to reinvert, leading to its surgical ligation. Little is known regarding the natural history of an inverted left atrial appendage. Danford et al. 7 reported subsequent reduction after it was identified in three patients but do not specify the indications for this. The decision for surgical eversion in this patient was based on concerns of incarceration and interference of left ventricular filling from the large atrial mass. In summary, transesophageal echocardiography provided imaging superior to transthoracic imaging and allowed diagnosis of an unusual left atrial mass as an inverted atrial appendage. The condition was corrected surgically and unnecessary anticoagulation was avoided. However, diagnosis by routine intraoperative transesophageal echocardiography allowing immediate correction would have prevented reoperation.
REFERENCES
1. Ritter SB. Transesophageal real-time echocardiography in infants and children with congenital heart disease. J Am CoU Cardiol 1991;18:569-80. 2. Wolfe LT, Rossi A, Ritter SB. Transesophageal echocardiography in infants and children: use and importance in the cardiac intensive care unit. I Am Soc Echocardiogr 1993; 6:286-9. 3. Bove EL, Lupinetti FM, Pridjian AK, et al. Results of a policy of primary repair oftruncus arteriosus in the neonate. J Thorac Cardiovasc Surg 1993;105:1057-66. 4. Seward JB, Khandheria BK, Oh JK, et al. Transesophaeai echocardiography: technique, anatomic correlations, implementation, and clinical applications. Mayo Clin Proc 1988;63:64980. 5. Seward JB, Khandheria BK, Edwards WD, Oh JK, Freeman WK, Tajik AJ. Biplanar transesophageal echocardiography: anatomic correlations, image orientation, and clinical applications. Mayo Clin Proc 1990;65:1193-213. 6. Aronson S, Ruo W, Sand M. Inverted left atrial appendage appearing as a left atrial mass with transesophageal echocardiography during cardiac surgery. Anesthesiology 1992;76: 1054-5. 7. Danford DA, Cheatham JP, Van Gundy JC, Mohiuddin SM, Fleming WH. Inversion of the left atrial appendage: clinical and echocardiographic correlates. Am Heart J 1994;127:71921.