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Evaluation of left atrial myxoma with transmission computed tomography
May, 1985
1116
Brief
Communications
Pulmonary accumulation of gallium-67 citrate is reported in active tuberculosis, bacterial pneumonia, intravenous drug abuse, pneumoconiosis,sarcoidosis,and idiopathic pulmonary fibrosis.gGallium scanning is capable of detecting primary bronchogenic carcinoma of all histologic types and malignant mesothelioma.gUptake of gallium in the lungs may be seenin opportunistic pulmonary infections in immunocompromisedpatients (e.g., Pneumocystis carinii pneumonia) prior to radiographic changes,and in somecaseswithout subsequentradiographic abnormalities.‘OIn addition, gallium imagingof the lungsin sarcoidosis may show increased uptake before any chest radiographic changes and may detect greater parenchymal involvement than the correspondingchest film in 20% to 25% of patients.” It is not known why gallium accumulatesin the lungsof patients with amiodaronepulmonary toxicity or why it is noted in drug-induced lung diseaserelated to nitrofurantoin and bleomycin therapy. Previous studies have speculated that the tracer uptake in areasof pneumonitis may be due to lactoferrin, an iron-binding protein found in polymorphonuclear leukocytes. Other researchimplicates T-lymphocytes, alveolar macrophages,or the inflammation itself, which may increase the permeability of the microvasculature permitting radionuclide to leak into the perivascular tissues.12~ I:’ It is not a clinical practice to use gallium-67 imaging to detect and follow the course of amiodarone pulmonary toxicity. Chest radiography currently representsthe primary diagnosticimagingmodality for evaluating this disease.This casesuggests,however, that gallium scintigraphy may complementthe chest film in detecting diseaseand following its evolution. While it is clinically useful in distinguishing between possibleamiodarone pneumonitis and congestiveheart failure, further studiesare necessaryto determine what the role of gallium imaging will be in the evaluation of amiodaronetoxicity. Its potential usefulnessdependson whether it is capable of better assessingthe extent of lung involvement by detecting early subclinical and radiographically occult amiodarone pulmonary toxicity. REFERENCES
1. Nademanee K, Singh B, Hendrickson J, lntarachot V, Lopez B, Feld G, et al: Amiodarone in refractory life-threatening ventricular arrhythmias. Ann Intern Med 98:577, 1980. 2. Heger JJ, Rystowsky EN, Jackman WM, Naccarelli GV, Warfel KA, Rinkenberger RL, et al: Amiodarone: Clinical efficacy and electrophysiology during long-term therapy for recurrent ventricular tachycardia or ventricular fibrillation. N Engl J Med 305:539, 1981. 3. Marchlinski FE, Gansler TS, Waxman HL, Josephson ME: Amiodarone pulmonary toxicity. An Intern Med 97:839, 1982. 4. Sobol SM, Rakita L: Pneumonitis and pulmonary fibrosis associated with amiodarone treatment: A possible complication of a new antiarrhythmic drug. Circulation 65:819, 1982. 5. Riley SA, Williams SE, Cooke NJ: Alveolitis after treatment with amiodarone. Br Med J 284:161, 1982. 6. Suarez LD, Poderoso JJ, Elsner V, Bunster AM, Esteva H, Bellotti M: Subacute pneumopathy during amiodarone therapy. Chest 83:566, 1983. 7. Jirik FR, Henningh H, Huckell VF, Ostrow DVN: Diffuse
American
Heart Journal
alveolar damage syndrome associated with amiodarone therapy. Can Med Assoc J 128:1192, 1983. 8. Rakita L, Sob01 SM, Mostow ND, Vrobel T: Amiodarone pulmonary toxicity. AM HEART J 106:906, 1983. 9. Bekerman C, Hoffer PB, Bitran JD, Gupta RG: Gallium-67 citrate imaging studies of the lung. Semin Nucl Med 10:286, 1980.
Hoffer P: Gallium and infection. J Nucl Med 21:484, 1980. Siemsen JK, Grebe SF, Sargent EN, Wentz D: Gallium-67 scintigraphy of pulmonary disease as a complement to radiography. Radiology 118:371, 1976. 12. Crook MJ, Kaplan PD, Adatepe MH: Gallium-67 scanning in nitrofurantoin-induced pulmonary reaction. J Nucl Med 23:690, 1982. 13. Richman SD, Levenson SM, Bunn PA: Gallium-67 accumulation in pulmonary lesions associated with bleomycin toxicity. Cancer 38:1966, 1975. 10. 11.
Evaluation of left atrial myxoma with transmission computed tomography Naoki Kawai, M.D., Iwao Sotobata, M.D., Masatsugu Iwase, M.D., Kazuhito Shiki, M.D., Mitsuhiro Yokota, M.D., Minoru Tanaka, M.D., Kazumasa Kondo, M.D., Nobuyuki Iwamura, M.D., and Tetsuo Tsuchida, M.D. Nagoya, Japan Myxomas are the most common type of primary cardiac tumors and must be surgically excised for complete cure. The recent development of noninvasive echocardiographic and radionuclide techniques hasmade it relatively simple and safeto detect and evaluate myxomaspreoperatively.‘-” However, thesetechniques have somelimitations in evaluating the fibrovascular stalk and calcification of the tumor. The present report demonstratesthe clinical usefulness of ECG-gated or ungated transmissioncomputed tomography in evaluating left atria1 myxomas. The clinical material consistedof four patients with atria1 myxoma diagnosedby routine echocardiographicevaluation. There were three men and one woman with a mean age of 62.5 years. Surgical removal was performed in each patient except for a 67-year-old woman patient. Transmission computed tomography (CT) was performed with a whole body scanner(SiemensSomatom 2 or Ohio Nuclear Delta 2020) under intravenous infusion of contrast medium, megluminediatrizoate.4 ECG-gated imageswere obtained in three patients and ECG-ungated views wereobtained in all four at left atria1 and ventricular level. Four serial scanningswere performed with simultaneousECG recording to obtain the ECG-gated images. Myxomas were shown as a low density massin the CT From the First Department of Internal Medicine and the Department of Thoracic Surgery, Nagoya University School of Medicine; and Nagoya City Higashi General Hospital. Reprint requests: Naoki Kawai, M.D., The First Department of Internal Medicine, Nagoya University School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466, Japan.
Volume Number
109 5, Part 1
Brief Communications
1117
Ungated
Case 1
T.W. 56M
1. ECG-gated and ungated cardiac CT imagesin caseNo. 1. ECG-gated imagesshow clearly the shapeand movement of the tumor. The attachment of the myxoma to the interatrial septum with a stalk (arrow) was demonstrated in the end-diastolic phase of ECG-gated images. RV = right ventricle; RA = right atrium; IVS = interventricular septum; LV = left ventricle; LA = left atrium; M = myxoma; DA = descendingaorta. Fig.
Case 2
Case 3
Case 4
2. Ungated cardiac CT images in casesNo. 2 (left), 3 (middle), and 4 (right). Calcification was shown in the stalk (caseNo. 2) and body of the tumor (caseNo. 3). AFFOWS showthe attachment of the tumor to the interatrial septum. LVO = left ventricular outflow tract. Fig.
images. In addition, ECG-gated cardiac CT clearly revealed piston movement of the tumor in casesNo. 1 and 2. It protruded into the left ventricle across the mitral orifice in diastole and returned to the left atrium in systole (Fig. 1). The grosspathologic specimenwasvery similar in shape to the low density massobserved in end-diastolic images. The attachment of myxomas to the interatrial
septum was recognized in ungated CT images of two patients (casesNo. 2 and 4) (Fig. 2). However, in a patient with a large myxoma (caseNo. l), the stalk of the tumor and its attachment to the interatrial septum were clearly observed in ECG-gated but not in ungated CT images (Fig. 1). At surgery of caseNo. 1, a 7 by 4.5 by 2.5 cm left atria1 myxoma weighing 73 gm was observed to attach to
tdah
1118
Brief Communications
the interatrial septum at the right margin of the fossa ovalis by a fibrous stalk. In case No. 3, the tumor attached tightly to the anterior wall of the left atrium with no stalk and was confirmed at surgery to have poor mobility; this had been preoperatively predicted with CT images as well as two-dimensional echocardiograms. Cardiac CTs showed calcified myxoma in two cases. Calcification was observed in the fibrous base of the stalk in case No. 2 and in the body of the tumor in case No. 3 (Fig. 2). Few studies have been made to evaluate atria1 myxomas with transmission CT.5,6 Ungated CT was considered to be useful in diagnosing calcification of the tumor and in evaluating the attachment of the stalk to the endocardium. ECG-gated scans were relatively useful in evaluating the shape, motion, and stalk of the tumor, especially in a large myxoma.
American
Heart
1985
Journal
REFERENCES
1. Wolfe SB, Popp RL, Feigenbaum H: Diagnosis of atria1 tumors by ultrasound. Circulation 39:615, 1969. 2. Finegan RE, Harrison DC: Diagnosis of left atria1 myxoma by echocardiography. N Engl J Med 282:1022, 1970. 3. Pohost GM. Pastore JO. McKusick KA. Chiotellis PN. Kapellakis GZ, Myers GS; Dinsmore RE, Block PC: Detection of left atria1 myxoma by gated radionuclide cardiac imaging. Circulation 5588, 1977. 4. Kawai N, Sotobata I, Noda S, Okada M, Kondo T, Yokota M, Yamauchi K, Tsuzuki J: Correlation between the direction of the interventricular septum estimated with transmission computed tomography and the initial QRS vectors. J Electrocardiol 17:401, 1984. 5. Godwin JD, Axe1 L, Adams JR, Schiller NB, Simpson PC, Gertz EW: Computed tomography: A new method for diagnosing tumor of the heart. Circulation 63:448, 1981. K, Thurn P: Computed tomography of the heart: 6. Lackner ECG-gated and continuous scans. Radiology 140:413, 1981.
1116
Brief
Communications
Pulmonary accumulation of gallium-67 citrate is reported in active tuberculosis, bacterial pneumonia, intravenous drug abuse, pneumoconiosis,sarcoidosis,and idiopathic pulmonary fibrosis.gGallium scanning is capable of detecting primary bronchogenic carcinoma of all histologic types and malignant mesothelioma.gUptake of gallium in the lungs may be seenin opportunistic pulmonary infections in immunocompromisedpatients (e.g., Pneumocystis carinii pneumonia) prior to radiographic changes,and in somecaseswithout subsequentradiographic abnormalities.‘OIn addition, gallium imagingof the lungsin sarcoidosis may show increased uptake before any chest radiographic changes and may detect greater parenchymal involvement than the correspondingchest film in 20% to 25% of patients.” It is not known why gallium accumulatesin the lungsof patients with amiodaronepulmonary toxicity or why it is noted in drug-induced lung diseaserelated to nitrofurantoin and bleomycin therapy. Previous studies have speculated that the tracer uptake in areasof pneumonitis may be due to lactoferrin, an iron-binding protein found in polymorphonuclear leukocytes. Other researchimplicates T-lymphocytes, alveolar macrophages,or the inflammation itself, which may increase the permeability of the microvasculature permitting radionuclide to leak into the perivascular tissues.12~ I:’ It is not a clinical practice to use gallium-67 imaging to detect and follow the course of amiodarone pulmonary toxicity. Chest radiography currently representsthe primary diagnosticimagingmodality for evaluating this disease.This casesuggests,however, that gallium scintigraphy may complementthe chest film in detecting diseaseand following its evolution. While it is clinically useful in distinguishing between possibleamiodarone pneumonitis and congestiveheart failure, further studiesare necessaryto determine what the role of gallium imaging will be in the evaluation of amiodaronetoxicity. Its potential usefulnessdependson whether it is capable of better assessingthe extent of lung involvement by detecting early subclinical and radiographically occult amiodarone pulmonary toxicity. REFERENCES
1. Nademanee K, Singh B, Hendrickson J, lntarachot V, Lopez B, Feld G, et al: Amiodarone in refractory life-threatening ventricular arrhythmias. Ann Intern Med 98:577, 1980. 2. Heger JJ, Rystowsky EN, Jackman WM, Naccarelli GV, Warfel KA, Rinkenberger RL, et al: Amiodarone: Clinical efficacy and electrophysiology during long-term therapy for recurrent ventricular tachycardia or ventricular fibrillation. N Engl J Med 305:539, 1981. 3. Marchlinski FE, Gansler TS, Waxman HL, Josephson ME: Amiodarone pulmonary toxicity. An Intern Med 97:839, 1982. 4. Sobol SM, Rakita L: Pneumonitis and pulmonary fibrosis associated with amiodarone treatment: A possible complication of a new antiarrhythmic drug. Circulation 65:819, 1982. 5. Riley SA, Williams SE, Cooke NJ: Alveolitis after treatment with amiodarone. Br Med J 284:161, 1982. 6. Suarez LD, Poderoso JJ, Elsner V, Bunster AM, Esteva H, Bellotti M: Subacute pneumopathy during amiodarone therapy. Chest 83:566, 1983. 7. Jirik FR, Henningh H, Huckell VF, Ostrow DVN: Diffuse
American
Heart Journal
alveolar damage syndrome associated with amiodarone therapy. Can Med Assoc J 128:1192, 1983. 8. Rakita L, Sob01 SM, Mostow ND, Vrobel T: Amiodarone pulmonary toxicity. AM HEART J 106:906, 1983. 9. Bekerman C, Hoffer PB, Bitran JD, Gupta RG: Gallium-67 citrate imaging studies of the lung. Semin Nucl Med 10:286, 1980.
Hoffer P: Gallium and infection. J Nucl Med 21:484, 1980. Siemsen JK, Grebe SF, Sargent EN, Wentz D: Gallium-67 scintigraphy of pulmonary disease as a complement to radiography. Radiology 118:371, 1976. 12. Crook MJ, Kaplan PD, Adatepe MH: Gallium-67 scanning in nitrofurantoin-induced pulmonary reaction. J Nucl Med 23:690, 1982. 13. Richman SD, Levenson SM, Bunn PA: Gallium-67 accumulation in pulmonary lesions associated with bleomycin toxicity. Cancer 38:1966, 1975. 10. 11.
Evaluation of left atrial myxoma with transmission computed tomography Naoki Kawai, M.D., Iwao Sotobata, M.D., Masatsugu Iwase, M.D., Kazuhito Shiki, M.D., Mitsuhiro Yokota, M.D., Minoru Tanaka, M.D., Kazumasa Kondo, M.D., Nobuyuki Iwamura, M.D., and Tetsuo Tsuchida, M.D. Nagoya, Japan Myxomas are the most common type of primary cardiac tumors and must be surgically excised for complete cure. The recent development of noninvasive echocardiographic and radionuclide techniques hasmade it relatively simple and safeto detect and evaluate myxomaspreoperatively.‘-” However, thesetechniques have somelimitations in evaluating the fibrovascular stalk and calcification of the tumor. The present report demonstratesthe clinical usefulness of ECG-gated or ungated transmissioncomputed tomography in evaluating left atria1 myxomas. The clinical material consistedof four patients with atria1 myxoma diagnosedby routine echocardiographicevaluation. There were three men and one woman with a mean age of 62.5 years. Surgical removal was performed in each patient except for a 67-year-old woman patient. Transmission computed tomography (CT) was performed with a whole body scanner(SiemensSomatom 2 or Ohio Nuclear Delta 2020) under intravenous infusion of contrast medium, megluminediatrizoate.4 ECG-gated imageswere obtained in three patients and ECG-ungated views wereobtained in all four at left atria1 and ventricular level. Four serial scanningswere performed with simultaneousECG recording to obtain the ECG-gated images. Myxomas were shown as a low density massin the CT From the First Department of Internal Medicine and the Department of Thoracic Surgery, Nagoya University School of Medicine; and Nagoya City Higashi General Hospital. Reprint requests: Naoki Kawai, M.D., The First Department of Internal Medicine, Nagoya University School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466, Japan.
Volume Number
109 5, Part 1
Brief Communications
1117
Ungated
Case 1
T.W. 56M
1. ECG-gated and ungated cardiac CT imagesin caseNo. 1. ECG-gated imagesshow clearly the shapeand movement of the tumor. The attachment of the myxoma to the interatrial septum with a stalk (arrow) was demonstrated in the end-diastolic phase of ECG-gated images. RV = right ventricle; RA = right atrium; IVS = interventricular septum; LV = left ventricle; LA = left atrium; M = myxoma; DA = descendingaorta. Fig.
Case 2
Case 3
Case 4
2. Ungated cardiac CT images in casesNo. 2 (left), 3 (middle), and 4 (right). Calcification was shown in the stalk (caseNo. 2) and body of the tumor (caseNo. 3). AFFOWS showthe attachment of the tumor to the interatrial septum. LVO = left ventricular outflow tract. Fig.
images. In addition, ECG-gated cardiac CT clearly revealed piston movement of the tumor in casesNo. 1 and 2. It protruded into the left ventricle across the mitral orifice in diastole and returned to the left atrium in systole (Fig. 1). The grosspathologic specimenwasvery similar in shape to the low density massobserved in end-diastolic images. The attachment of myxomas to the interatrial
septum was recognized in ungated CT images of two patients (casesNo. 2 and 4) (Fig. 2). However, in a patient with a large myxoma (caseNo. l), the stalk of the tumor and its attachment to the interatrial septum were clearly observed in ECG-gated but not in ungated CT images (Fig. 1). At surgery of caseNo. 1, a 7 by 4.5 by 2.5 cm left atria1 myxoma weighing 73 gm was observed to attach to
tdah
1118
Brief Communications
the interatrial septum at the right margin of the fossa ovalis by a fibrous stalk. In case No. 3, the tumor attached tightly to the anterior wall of the left atrium with no stalk and was confirmed at surgery to have poor mobility; this had been preoperatively predicted with CT images as well as two-dimensional echocardiograms. Cardiac CTs showed calcified myxoma in two cases. Calcification was observed in the fibrous base of the stalk in case No. 2 and in the body of the tumor in case No. 3 (Fig. 2). Few studies have been made to evaluate atria1 myxomas with transmission CT.5,6 Ungated CT was considered to be useful in diagnosing calcification of the tumor and in evaluating the attachment of the stalk to the endocardium. ECG-gated scans were relatively useful in evaluating the shape, motion, and stalk of the tumor, especially in a large myxoma.
American
Heart
1985
Journal
REFERENCES
1. Wolfe SB, Popp RL, Feigenbaum H: Diagnosis of atria1 tumors by ultrasound. Circulation 39:615, 1969. 2. Finegan RE, Harrison DC: Diagnosis of left atria1 myxoma by echocardiography. N Engl J Med 282:1022, 1970. 3. Pohost GM. Pastore JO. McKusick KA. Chiotellis PN. Kapellakis GZ, Myers GS; Dinsmore RE, Block PC: Detection of left atria1 myxoma by gated radionuclide cardiac imaging. Circulation 5588, 1977. 4. Kawai N, Sotobata I, Noda S, Okada M, Kondo T, Yokota M, Yamauchi K, Tsuzuki J: Correlation between the direction of the interventricular septum estimated with transmission computed tomography and the initial QRS vectors. J Electrocardiol 17:401, 1984. 5. Godwin JD, Axe1 L, Adams JR, Schiller NB, Simpson PC, Gertz EW: Computed tomography: A new method for diagnosing tumor of the heart. Circulation 63:448, 1981. K, Thurn P: Computed tomography of the heart: 6. Lackner ECG-gated and continuous scans. Radiology 140:413, 1981.