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Isolated Supravalvular Stenosing Ring of Left Atrium: Diagnosis Before Operation and Successful Surgical Treatment
Isolated Supravalvular Stenosing Ring of Left Atrium: Diagnosis Before Operation and Successful Surgical Treatment* Kyung I . Chung, M.D.; James A. Manning, M.D.; Elliot 0. Lipchik, M.D.; Raymond Cramiak, M.D.; and Earle B. Mahoney, M.D.
A case of supravalvular stenosing ring of the left atrium without an associated cardiac lesion and the youngest (four-moath-dd) patient ever reported to survive operation with this lesion is presented. The importance of careful diganostic studies including clinical examination, rmgiocardiography and echocardiography before o p e d o n is emphrrsized. Since this lesion is potentially curable by operation, repair with use of cardiopulmonary bypass should be performed without delay once the diagnosis hrrs been made.
uring infancy and childhood, obstruction to emptying of the left atrium may be caused by any of the following malformations: the hypoplastic left heart syndrome, congenital mitral stenosis, parachute mitral valve, left atrial myxoma, cor triatriatum and supravalvular stenosing ring of the left atrium. Supravalvular stenosing ring of the left atrium is a rare malformation and has been associated with other cardiac defects, until the present report. Since Fisher1 described the first case in 1902, only 23 cases have been reported in the literature. In this malformation, a membrane or a shelflike structure with one or two narrow orifices is located close to the mitral annulus and obstructs outflow from the left atrium. The left atrial appendage and the foramen ovale are located above the membrane, differentiating this anomaly from cor triatriatum ( Fig 1). The origin of the supravalvular stenosing ring is not clear. It was interpreted by Rogeq2 in one case, as being an acquired jet lesion from the mitral insufficiency accompanying endocardiosclerosis of the left ventricle. Later, Manubenss described it as congenital in origin. This paper presents the clinical and, in particular, *From the Departments of Pediatrics, Radiology and Surgery, The University of Rochester Medical Center, Rochester, N.Y. This study was supported by Grant l R O l HL15186-01 from the National Institutes of Health, Bethesda, Md., and by the Genesee Valley Heart Association, Inc. Manuscript received July 5; accepted July 16. Reprint requests: Dr. Manning, Department of Pediatrics, Unioer.Pity of Rochester Medical Center, 280 Critterden Blvd., Rochester, N.Y. 14642
CHEST, VOL. 65, NO. 1, JANUARY, 1974
the echocardiographic findings which make the patient unique. To the best of our knowledge, his case becomes the only one in the literature with the correct diagnosis before operation. He is the youngest patient to have successful correction at operation.
This patient was a product of a 32-week gestation, with a birth weight of 1,500 gm. The patient ( a boy) had a mild respiratory distress syndrome during the newborn period, with an uneventful recovery. Following discharge from the hospital, at age ten days, he had excessive sweating, frequent cough and heavy breathing. He was readmitted at age three and one-half months for tachycardia and respiratory distress due to congestive heart failure. The physical examination revealed a pale and dyspneic infant in moderate distress. The temperature was 36.8-C, pulse rate was lM/minute, respiratory rate was 93/minute, and the blood pressure in the right arm was 90/% mm Hg. He weighed 4.8 kg (third percentile) and measured 56 cm (third percentile). The chest was symmetrical bilaterally, and there were no rllles or dullness on auscultation and percussion. The precordium was quiet and the point of maximum intensity was at the fifth intercostal space, about 5 cm from the left sternal margin. There was a grade 2/6 harsh pansystolic murmur at the apex, radiating- to the left adlla. The first heart sound was normal. and the second heart sound was split, with accentuation of the pulmonic closure sound. There was no rub or gallop sound. The liver was palpable 3 cm below the right costal margin. The peripheral pulses were normal. The pertinent laboratory data revealed a hemoglobin level of 14.2 gm percent, with a normal peripheral blood smear. The serum electrolyte and enzyme readings were normal. The electrocardiogram showed a sinus rhythm with a QRS axis of +130. There was marked right ventricular hypertrophy and sugges-
CHUNG ET AL
RPV.
FIGUHE1. Schematic drawings of supravalvular stenosing ring of left atrium. Ao: aorta, CS: coronary sinus, FO: foramen ovale, LA: left atrium, LAA: left atrial appendage, LPV: left pulmonary vein, MV: mitral valve, RA: right atrium, RPV: right pulmonary vein, SR: supravalvular ring, TV: tricuspid valve. tive left atrial enlargement (Fig 2). The chest x-ray film showed moderate cardiomegaly with an enlarged left atrium and evidence of pulmonary venous congestion without increased pulmonary arterial flow. Prior to angiocardiography, the echocardiogram showed a normal mitral valve and a persistent linear structure in the left atrium (Fig 3). The clinical diagnosis was either supravalvular stenosing ring of the left atrium or cor triatriatum. The patient underwent right heart catheterization. The findings are presented in Table 1. The angiocardiogram, biplane serial studies after the injection of contrast material into the main pulmonary artery, demonstrated a stenosing ring close to the mitral valve, dividing the atrium into two compartments (Fig 4). The proximal larger compartment received the pulmonary veins, and was the origin of the appendage. The distal compartment was substantially smaller. with the peripheral aspects of the ring quite close to the mitral annulus. There was no evidence of a subaortic stenosis, or other abnormalities of the left atrium, left ventricle, aortic vdve or aorta. In view of the severity of the patient's condition and the potential of surgical cure of this lesion, the patient underwent
FIGURE2. ECG before operation shows QRS axis of +130 and evidence of right ventricular and left atrial hypertrophy.
operation for removal of the supravalvular ring at the age of four months. The operation was performed utilizing cardiopulmonary bypass with an infant size Temptrol oxygenator through median sternotomy. The usual caval camulations were performed, the ascending aorta was used for arterial return and the left ventricle was vented. At operation, the left atrium was very large and bulged to
FIGURE3. Echocardiogram from patient before operation. (A, upper). Mitral valve amplitude and diastolic slope are normal, which differentiates this case from congenital mitral stenosis. (B, h e r ) . As ultrasound beam scans from mitral valve to aortic root, abnormal echo as membranous structure at left atrial outflow (arrow) becomes apparent. Also Note enlarged left atrium). ECG: electrocardiogram, LA: left atrium, MV: mitral valve, PHONO: phonocardiogram, VS: ventricular septum.
CHEST, VOL. 65, NO. 1, JANUARY, 1974
ISOLATED SUPRAVALVULAR STENOSING RING OF LEFT ATRIUM Table 1 4 a r d i a c Catheterisation Data Position
Pressure, mm Hg
Superior vena cava
~ygen Saturation, O/o 68
Right atrium Inferior vena cava Right ventricle
130/4
Main pulmonary artery
130/59 m =65
67
the right beneath the right atrium. The bulging left atrium was incised and by elevating the septum and right atrium, the membranous ring could be visualized and noted to completely obscure the mitral valve. The four pulmonary veins were identified entering the left atrium. There was a tiny opening through the ring which could be dilated with a hemostat and the attachments could be defined. The ring was totally excised, revealing the mitral valve which appeared normal. The left atrium was closed and the procedure terminated in the usual manner. The heart responded well and the arterial pressure was normal following bypass. The patient has been observed for eight months after the operation and remains well at present. The electrocardiogram shows decreasing right ventricular hypertrophy, with a QRS axis of +90. There is no residual heart murmur, and he has a nonnal second heart sound. The chest x-ray film shows minimal cardiomegaly without evidence of pulmonary venous congestion. The echocardiography shows a normal-sized left atrium with a minimal residual membranous structure in the left atrium.
Clinical Features Among the 23 patients reported in the literature, a
FIGURE 4. A n g i d i o g r a m after injection of contrast material into pulmonary artery. Antemposterior film 1.5 seconds after injection) shows intra-atrial membrane as linear filling defect (singk arrow) and left atrial enlargement above membrane. Mitral valve appears normal (double a m ) .
CHEST, VOL. 65, NO. 1, JANUARY, 1974
diagnosis of 16 cases was made at postmortem examination,'-lo three at the time of o p e r a t i ~ n $ ~ ~ , ' ~ and only four were detected before operation.1915 Manubens et al: in reporting their cases of supravalvular mitral stenosis, were unable to differentiate these cases clinically from isolated ventricular septal defect with pulmonary hypertension. Lynch et alls reported a 10%-year-oldboy with a supravalvular stenosing ring associated with a ventricular septal defect with a diagnosis made from the clinical findings and the phonocardiogram. In our patient, the following several parameters suggested the correct diagnosis before cardiac catheterization: the patient had an apical systolic murmur with an increased pulmonic closure sound associated with congestive heart failure. Right ventricular hypertrophy, left atrial enlargement with right axis deviation on electrocardiogram, plus moderate cardiomegaly with pulmonary venous congestion without increased pulmonary arterial blood flow on the chest x-ray film were also indicative of pulmonary venous obstruction. Echocardiography demonstrated a normal mitral valve and strongly suggested the presence of membranelike structure in the left atrium.
Cardiac Catheterization and Angwcardwgraphy Cardiac catheterization revealed only a systemic pressured right ventricle and main pulmonary artery, without intracardiac shunting. A pulmonary wedge pressure was not obtained, thus making it impossible to exclude primary pulmonary hypertension. The presence of the supravalvular ring was clearly demonstrated by the angiocardiogram. Identical angiocardiographic pictures were described by Mehrizi et all4 in a patient with supravalvular stenosing ring and by Miller et all6 and Ellis et all7 in those with cor triatriatum. From the experience in the present patient and a patient with cor triatriatum, as well as from the reports of Mehrizi,14 Miller16 and Ellis,17 we feel a main pulmonary artery injection of contrast material in order to demonstrate the left atrial anatomy is the diagnostic procedure of choice in this anomaly. Surgery Since Lynch et all3 reported the first successful operation for this anomaly in 1962, there have been few reports on the surgical treatment of the lesion. All patients reported have had associated anomalies. In all but one,13 the mitral valve was deformed and required surgical repair. In our patient, the mitral valve was found to be normal and no other cardiac abnormalities were present. Since operation, he has had no evidence of residual cardiac anomaly. The importance of the early diagnosis of this lesion is
CHUNG ET AL
evident. Failure to do so has resulted in a fatal outcome in the period following operation for repair of associated anomalies," and the pulmonary vascular disease in the hemodynamically similar cor triatriatum has been reported on necropsy s t ~ d i e s . ' ~ .This ' ~ membrane may be closely attached to the mitral valve. It requires a meticulous surgical technique to avoid injury to the rnitral valve itself.
The Diagnostic Value of Echocardiography The patient was studied with use of ultrasound twice before the cardiac catheterization. An effort was made to evaluate the function and the anatomy of the left side of the heart. The mitral valve structure and function were in the normal range, which ruled out congenital mitral stenosis as the cause of the pulmonary venous obstruction. Also, the patient has a normal-sized left ventricle. With slow scanning from the left ventricle to the aortic root, a membranelike structure in the left atrium with marked dilatation of the left atrium was recorded. These findings were consistent with the clinical diagnosis of supravalvular ring. Lund~trom'~ reported a case of supravalvular stenosing ring in which he recorded an abnormal echo in the left atrium apparently arising from this membrane. Echocardiogram, therefore, has a potential value in the diagnosis of supravalvular stenosing ring. It is logical to assume that the diagnosis of cor triatriatum may also be possible by echocardiography. 1 Fisher T : Two cases of congenital disease of the left side of the heart. Br Med J 1:639-641, 1902 2 Rogers HM, Waldron BR, Murphey DFH, et al: Supravalvular stenosing ring of left atrium in association with endocardial sclerosis (endocardia1 fibroelastosis) and mitral insufficiency. Am Heart J 50:777-781, 1955 3 Manubens R, Krovetz LJ, Adams P: Supravalvular stenosing ring of the left atrium. Am Heart J 60:286-295, 1960 4 Shone JD, Sellers RD, Anderson RL, et al: The develop-
mental complex of "parachute mitral valve," supravalvular ring of left atrium, subaortic stenosis and coarctation of aorta. Am J Cardiol 11:714-725, 1963 5 Helmholz HF, Daugherty GW, Edwards JE: Cardiac clinics CXLV: Congenital "mitral" insufficiency in association with corrected transposition of the great vessels: Report of probable clinical case and review of six cases studied pathologically. Mayo Clin Proc 31:81-91, 1956 6 Kipkie GF, Johnson DS: Possible pathogenic mechanisms responsible for human periarteritis nodosa, as suggested by the occurrence of two instances of this disease in association with glomerulonephritis. Arch Path01 51:387392, 1951 7 Johnson NJ, Dodd K: Obstruction to left atrial outflow by a supravalvular stenosing ring. J Pediatr 51:190-193, 1957 8 Cassano GB: Congenital annular stenosis of the left atrioventricular canal: so-called supravalvular mitral stenosis. Am J Cardiol 13:708-713, 1964 9 Rao S, Anderson RL, Lucas RV, et al: Supravalvular stenosing ring of left atrium. Am Heart J 77:538-545, 1969 10 Lundstrom NR: Ultrasound cardiographic studies of the mitral valve region in young infants with mitral atresia, mitral stenosis, hypoplasia of the left ventricle and cor triatriatum. Circulation 45:324-334, 1972 11 Stretton TB, Fentem PH: Stenosis of the left atrioventricular canal. Br Heart J 24237-240, 1962 12 Anabtawi IN, Ellison RG: Congenital stenosing ring of the left atrioventricular canal (supravalvular mitral stenosis). J Thorac Cardiovasc Surg 49:994-1005, 1965 13 Lynch MF, Ryan NJ, Williams GR, et al: Preoperative diagnosis and surgical correction of supravalvular mitral stenosis and ventricular septa1 defect. Circulation 25:854861, 1962 14 Mehrizi A, Hutchins GM, Wilson EF, et al: Supravalvular mitral stenosis. J Pediatr 67: 1141-1149, 1965 15 Chesler EC, Beck W, Barnard CN, et al: Supravalvular stenosing ring of the left atrium associated with corrected transposition of the great vessels. Am J Cardiol 31:84-88, 1973 16 Miller GAH, Ongley PA, Anderson MW, et al: Cor triatriatum. Hemodynamic and angiocardiographic diagnosis. Am Heart J 68:298-304, 1964 17 Ellis K, Gri5ths SP, Jesse MJ, et al: Cor triatriatum. Angiocardiographic demonstration of the obstructing left atrial membrane. Am J Roentgen01 Radium Ther Nucl Med 92:669-674, 1964 18 Niwayama G: Cor triatriatum. Am Heart J 59:291-317, 1960
CHEST, VOL. 65, NO. 1, JANUARY, 1 9 7 4
A case of supravalvular stenosing ring of the left atrium without an associated cardiac lesion and the youngest (four-moath-dd) patient ever reported to survive operation with this lesion is presented. The importance of careful diganostic studies including clinical examination, rmgiocardiography and echocardiography before o p e d o n is emphrrsized. Since this lesion is potentially curable by operation, repair with use of cardiopulmonary bypass should be performed without delay once the diagnosis hrrs been made.
uring infancy and childhood, obstruction to emptying of the left atrium may be caused by any of the following malformations: the hypoplastic left heart syndrome, congenital mitral stenosis, parachute mitral valve, left atrial myxoma, cor triatriatum and supravalvular stenosing ring of the left atrium. Supravalvular stenosing ring of the left atrium is a rare malformation and has been associated with other cardiac defects, until the present report. Since Fisher1 described the first case in 1902, only 23 cases have been reported in the literature. In this malformation, a membrane or a shelflike structure with one or two narrow orifices is located close to the mitral annulus and obstructs outflow from the left atrium. The left atrial appendage and the foramen ovale are located above the membrane, differentiating this anomaly from cor triatriatum ( Fig 1). The origin of the supravalvular stenosing ring is not clear. It was interpreted by Rogeq2 in one case, as being an acquired jet lesion from the mitral insufficiency accompanying endocardiosclerosis of the left ventricle. Later, Manubenss described it as congenital in origin. This paper presents the clinical and, in particular, *From the Departments of Pediatrics, Radiology and Surgery, The University of Rochester Medical Center, Rochester, N.Y. This study was supported by Grant l R O l HL15186-01 from the National Institutes of Health, Bethesda, Md., and by the Genesee Valley Heart Association, Inc. Manuscript received July 5; accepted July 16. Reprint requests: Dr. Manning, Department of Pediatrics, Unioer.Pity of Rochester Medical Center, 280 Critterden Blvd., Rochester, N.Y. 14642
CHEST, VOL. 65, NO. 1, JANUARY, 1974
the echocardiographic findings which make the patient unique. To the best of our knowledge, his case becomes the only one in the literature with the correct diagnosis before operation. He is the youngest patient to have successful correction at operation.
This patient was a product of a 32-week gestation, with a birth weight of 1,500 gm. The patient ( a boy) had a mild respiratory distress syndrome during the newborn period, with an uneventful recovery. Following discharge from the hospital, at age ten days, he had excessive sweating, frequent cough and heavy breathing. He was readmitted at age three and one-half months for tachycardia and respiratory distress due to congestive heart failure. The physical examination revealed a pale and dyspneic infant in moderate distress. The temperature was 36.8-C, pulse rate was lM/minute, respiratory rate was 93/minute, and the blood pressure in the right arm was 90/% mm Hg. He weighed 4.8 kg (third percentile) and measured 56 cm (third percentile). The chest was symmetrical bilaterally, and there were no rllles or dullness on auscultation and percussion. The precordium was quiet and the point of maximum intensity was at the fifth intercostal space, about 5 cm from the left sternal margin. There was a grade 2/6 harsh pansystolic murmur at the apex, radiating- to the left adlla. The first heart sound was normal. and the second heart sound was split, with accentuation of the pulmonic closure sound. There was no rub or gallop sound. The liver was palpable 3 cm below the right costal margin. The peripheral pulses were normal. The pertinent laboratory data revealed a hemoglobin level of 14.2 gm percent, with a normal peripheral blood smear. The serum electrolyte and enzyme readings were normal. The electrocardiogram showed a sinus rhythm with a QRS axis of +130. There was marked right ventricular hypertrophy and sugges-
CHUNG ET AL
RPV.
FIGUHE1. Schematic drawings of supravalvular stenosing ring of left atrium. Ao: aorta, CS: coronary sinus, FO: foramen ovale, LA: left atrium, LAA: left atrial appendage, LPV: left pulmonary vein, MV: mitral valve, RA: right atrium, RPV: right pulmonary vein, SR: supravalvular ring, TV: tricuspid valve. tive left atrial enlargement (Fig 2). The chest x-ray film showed moderate cardiomegaly with an enlarged left atrium and evidence of pulmonary venous congestion without increased pulmonary arterial flow. Prior to angiocardiography, the echocardiogram showed a normal mitral valve and a persistent linear structure in the left atrium (Fig 3). The clinical diagnosis was either supravalvular stenosing ring of the left atrium or cor triatriatum. The patient underwent right heart catheterization. The findings are presented in Table 1. The angiocardiogram, biplane serial studies after the injection of contrast material into the main pulmonary artery, demonstrated a stenosing ring close to the mitral valve, dividing the atrium into two compartments (Fig 4). The proximal larger compartment received the pulmonary veins, and was the origin of the appendage. The distal compartment was substantially smaller. with the peripheral aspects of the ring quite close to the mitral annulus. There was no evidence of a subaortic stenosis, or other abnormalities of the left atrium, left ventricle, aortic vdve or aorta. In view of the severity of the patient's condition and the potential of surgical cure of this lesion, the patient underwent
FIGURE2. ECG before operation shows QRS axis of +130 and evidence of right ventricular and left atrial hypertrophy.
operation for removal of the supravalvular ring at the age of four months. The operation was performed utilizing cardiopulmonary bypass with an infant size Temptrol oxygenator through median sternotomy. The usual caval camulations were performed, the ascending aorta was used for arterial return and the left ventricle was vented. At operation, the left atrium was very large and bulged to
FIGURE3. Echocardiogram from patient before operation. (A, upper). Mitral valve amplitude and diastolic slope are normal, which differentiates this case from congenital mitral stenosis. (B, h e r ) . As ultrasound beam scans from mitral valve to aortic root, abnormal echo as membranous structure at left atrial outflow (arrow) becomes apparent. Also Note enlarged left atrium). ECG: electrocardiogram, LA: left atrium, MV: mitral valve, PHONO: phonocardiogram, VS: ventricular septum.
CHEST, VOL. 65, NO. 1, JANUARY, 1974
ISOLATED SUPRAVALVULAR STENOSING RING OF LEFT ATRIUM Table 1 4 a r d i a c Catheterisation Data Position
Pressure, mm Hg
Superior vena cava
~ygen Saturation, O/o 68
Right atrium Inferior vena cava Right ventricle
130/4
Main pulmonary artery
130/59 m =65
67
the right beneath the right atrium. The bulging left atrium was incised and by elevating the septum and right atrium, the membranous ring could be visualized and noted to completely obscure the mitral valve. The four pulmonary veins were identified entering the left atrium. There was a tiny opening through the ring which could be dilated with a hemostat and the attachments could be defined. The ring was totally excised, revealing the mitral valve which appeared normal. The left atrium was closed and the procedure terminated in the usual manner. The heart responded well and the arterial pressure was normal following bypass. The patient has been observed for eight months after the operation and remains well at present. The electrocardiogram shows decreasing right ventricular hypertrophy, with a QRS axis of +90. There is no residual heart murmur, and he has a nonnal second heart sound. The chest x-ray film shows minimal cardiomegaly without evidence of pulmonary venous congestion. The echocardiography shows a normal-sized left atrium with a minimal residual membranous structure in the left atrium.
Clinical Features Among the 23 patients reported in the literature, a
FIGURE 4. A n g i d i o g r a m after injection of contrast material into pulmonary artery. Antemposterior film 1.5 seconds after injection) shows intra-atrial membrane as linear filling defect (singk arrow) and left atrial enlargement above membrane. Mitral valve appears normal (double a m ) .
CHEST, VOL. 65, NO. 1, JANUARY, 1974
diagnosis of 16 cases was made at postmortem examination,'-lo three at the time of o p e r a t i ~ n $ ~ ~ , ' ~ and only four were detected before operation.1915 Manubens et al: in reporting their cases of supravalvular mitral stenosis, were unable to differentiate these cases clinically from isolated ventricular septal defect with pulmonary hypertension. Lynch et alls reported a 10%-year-oldboy with a supravalvular stenosing ring associated with a ventricular septal defect with a diagnosis made from the clinical findings and the phonocardiogram. In our patient, the following several parameters suggested the correct diagnosis before cardiac catheterization: the patient had an apical systolic murmur with an increased pulmonic closure sound associated with congestive heart failure. Right ventricular hypertrophy, left atrial enlargement with right axis deviation on electrocardiogram, plus moderate cardiomegaly with pulmonary venous congestion without increased pulmonary arterial blood flow on the chest x-ray film were also indicative of pulmonary venous obstruction. Echocardiography demonstrated a normal mitral valve and strongly suggested the presence of membranelike structure in the left atrium.
Cardiac Catheterization and Angwcardwgraphy Cardiac catheterization revealed only a systemic pressured right ventricle and main pulmonary artery, without intracardiac shunting. A pulmonary wedge pressure was not obtained, thus making it impossible to exclude primary pulmonary hypertension. The presence of the supravalvular ring was clearly demonstrated by the angiocardiogram. Identical angiocardiographic pictures were described by Mehrizi et all4 in a patient with supravalvular stenosing ring and by Miller et all6 and Ellis et all7 in those with cor triatriatum. From the experience in the present patient and a patient with cor triatriatum, as well as from the reports of Mehrizi,14 Miller16 and Ellis,17 we feel a main pulmonary artery injection of contrast material in order to demonstrate the left atrial anatomy is the diagnostic procedure of choice in this anomaly. Surgery Since Lynch et all3 reported the first successful operation for this anomaly in 1962, there have been few reports on the surgical treatment of the lesion. All patients reported have had associated anomalies. In all but one,13 the mitral valve was deformed and required surgical repair. In our patient, the mitral valve was found to be normal and no other cardiac abnormalities were present. Since operation, he has had no evidence of residual cardiac anomaly. The importance of the early diagnosis of this lesion is
CHUNG ET AL
evident. Failure to do so has resulted in a fatal outcome in the period following operation for repair of associated anomalies," and the pulmonary vascular disease in the hemodynamically similar cor triatriatum has been reported on necropsy s t ~ d i e s . ' ~ .This ' ~ membrane may be closely attached to the mitral valve. It requires a meticulous surgical technique to avoid injury to the rnitral valve itself.
The Diagnostic Value of Echocardiography The patient was studied with use of ultrasound twice before the cardiac catheterization. An effort was made to evaluate the function and the anatomy of the left side of the heart. The mitral valve structure and function were in the normal range, which ruled out congenital mitral stenosis as the cause of the pulmonary venous obstruction. Also, the patient has a normal-sized left ventricle. With slow scanning from the left ventricle to the aortic root, a membranelike structure in the left atrium with marked dilatation of the left atrium was recorded. These findings were consistent with the clinical diagnosis of supravalvular ring. Lund~trom'~ reported a case of supravalvular stenosing ring in which he recorded an abnormal echo in the left atrium apparently arising from this membrane. Echocardiogram, therefore, has a potential value in the diagnosis of supravalvular stenosing ring. It is logical to assume that the diagnosis of cor triatriatum may also be possible by echocardiography. 1 Fisher T : Two cases of congenital disease of the left side of the heart. Br Med J 1:639-641, 1902 2 Rogers HM, Waldron BR, Murphey DFH, et al: Supravalvular stenosing ring of left atrium in association with endocardial sclerosis (endocardia1 fibroelastosis) and mitral insufficiency. Am Heart J 50:777-781, 1955 3 Manubens R, Krovetz LJ, Adams P: Supravalvular stenosing ring of the left atrium. Am Heart J 60:286-295, 1960 4 Shone JD, Sellers RD, Anderson RL, et al: The develop-
mental complex of "parachute mitral valve," supravalvular ring of left atrium, subaortic stenosis and coarctation of aorta. Am J Cardiol 11:714-725, 1963 5 Helmholz HF, Daugherty GW, Edwards JE: Cardiac clinics CXLV: Congenital "mitral" insufficiency in association with corrected transposition of the great vessels: Report of probable clinical case and review of six cases studied pathologically. Mayo Clin Proc 31:81-91, 1956 6 Kipkie GF, Johnson DS: Possible pathogenic mechanisms responsible for human periarteritis nodosa, as suggested by the occurrence of two instances of this disease in association with glomerulonephritis. Arch Path01 51:387392, 1951 7 Johnson NJ, Dodd K: Obstruction to left atrial outflow by a supravalvular stenosing ring. J Pediatr 51:190-193, 1957 8 Cassano GB: Congenital annular stenosis of the left atrioventricular canal: so-called supravalvular mitral stenosis. Am J Cardiol 13:708-713, 1964 9 Rao S, Anderson RL, Lucas RV, et al: Supravalvular stenosing ring of left atrium. Am Heart J 77:538-545, 1969 10 Lundstrom NR: Ultrasound cardiographic studies of the mitral valve region in young infants with mitral atresia, mitral stenosis, hypoplasia of the left ventricle and cor triatriatum. Circulation 45:324-334, 1972 11 Stretton TB, Fentem PH: Stenosis of the left atrioventricular canal. Br Heart J 24237-240, 1962 12 Anabtawi IN, Ellison RG: Congenital stenosing ring of the left atrioventricular canal (supravalvular mitral stenosis). J Thorac Cardiovasc Surg 49:994-1005, 1965 13 Lynch MF, Ryan NJ, Williams GR, et al: Preoperative diagnosis and surgical correction of supravalvular mitral stenosis and ventricular septa1 defect. Circulation 25:854861, 1962 14 Mehrizi A, Hutchins GM, Wilson EF, et al: Supravalvular mitral stenosis. J Pediatr 67: 1141-1149, 1965 15 Chesler EC, Beck W, Barnard CN, et al: Supravalvular stenosing ring of the left atrium associated with corrected transposition of the great vessels. Am J Cardiol 31:84-88, 1973 16 Miller GAH, Ongley PA, Anderson MW, et al: Cor triatriatum. Hemodynamic and angiocardiographic diagnosis. Am Heart J 68:298-304, 1964 17 Ellis K, Gri5ths SP, Jesse MJ, et al: Cor triatriatum. Angiocardiographic demonstration of the obstructing left atrial membrane. Am J Roentgen01 Radium Ther Nucl Med 92:669-674, 1964 18 Niwayama G: Cor triatriatum. Am Heart J 59:291-317, 1960
CHEST, VOL. 65, NO. 1, JANUARY, 1 9 7 4