Successful use of deep hypothermic circulatory arrest in pregnancy

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CASE REPORT BUFFOLO ET AL HYPOTHERMIC CIRCULATORY ARREST IN PREGNANCY

operation was undertaken [1-6], 16 (64%) died. Among the 9 patients who survived operation, including ours, 1 underwent only right pulmonary artery banding; the other 8 patients underwent total repair [1, 5, 6], with a staged operation performed in 1 [5] (Table 2). A prosthetic tube was used to reconstruct the aortic arch in 4 patients (Nos. 2,3,4, and 7); turndown of the left subclavian artery was performed in 2 patients (Nos. 1 and 6), and an end-to-side anastomosis was carried out in 2 patients (Nos. 5 and 8). We used an intraarterial baffle in our patient to totally repair these lesions in one operation. Reoperation is inevitable in those patients who have a prosthetic tube implanted in infancy or early childhood. In patient 6, who underwent turndown of the left subclavian artery, coarctation recurred and was repaired 6 months later. Our patching method should circumvent these complications because the growth potential is preserved in the native aorta and pulmonary artery aspect of the reconstruction. Beside the growth potential, our technique has the following advantages. First, because the APSD itself was used as the proximal orifice of the arch reconstruction [4], the problem with managing the small ascending aorta (Fig lA) in the setting of such anomalies can be averted. Second, exposure is excellent and hemostasis is easy to accomplish with our method. It is not necessary to perform another thoracotomy [7, 8], and the tedious and poor exposure of deep arch structures afforded by a sternotomy can be avoided. Third, double aortic cannulation with conventional cardiopulmonary bypass makes it possible for total repair to be performed in one stage without the need for circulatory arrest. It may be questioned whether a patent ductus arteriosus can be used as part of arch reconstruction, but such a duct has been used successfully to construct a new arch [7, 8]. After studying the nature of ductal tissue in patients with IAA, Oppenheimer-Dekker and associates suggested that the duct or part of it can be used for reconstruction of the aortic arch after the age of 3 months in patients with a patent duct who have not been treated with prostaglandin E1 [4]. Follow-up color-Doppler echocardiography performed in our patient 6 months after the operation showed that the constricting effect of normal ductal tissue had not occurred (Fig 3). We conclude from our experience that intraarterial partition is simple and effective for one-stage repair of APSD and IAA with a widely patent duct, and that the aorta and pulmonary artery can be expected to grow as the child grows. References 1. Braunlin E, Peoples WM, Freedom RM, Fyler DC, Goldblatt A, Edwards JE. Interruption of the aortic arch with aorticopulmonary septal defect: an anatomic review. Pediatr Cardiol 1982;3: 329-35. 2. Kutsche LM, Van Mierop LHS. Anatomy and pathogenesis of aorticopulmonary septal defect. Am J Cardiol 1987;59:443-7. 3. Sissman NJ. Interrupted aortic arch with aortic septal defect. J Thorac Cardiovasc Surg 1978;75:902. 4. Oppenheimer-Dekker A, Gittenberger-de Groot AC, Roozendaal H. The ductus arteriosus and associated cardiac anomalies in interruption of the aortic arch. Pediatr CardioI1982;2:185-93. © 1994 by The Society of Thoracic Surgeons

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5. Tabak C, Moskowitz W, Wagner H, Weinberg P, Edmunds LH Jr. Aortopulmonary window and aortic isthmic hypoplasia: operative management in newborn infants. J Thorac Cardiovasc Surg 1983;86:273-9. 6. Ding WX, Su ZK, Cao DF, Jonas RA. One-stage repair of absence of the aortopulmonary septum and interrupted aortic arch. Ann Thorac Surg 1990;49:664-6. 7. Monro JL, Brawn W, Conway N. Correction of type B interrupted aortic arch with ventricular septal defect in infancy. J Thorac Cardiovasc Surg 1977;74:618-23. 8. Muraoka R, Yokota M, Aoshima M, et al. Simplified method for total correction of interrupted aortic arch with ventricular septal defect in infancy. J Thorac Cardiovasc Surg 1979;78: 744-9.

Successful Use of Deep Hypothermic Circulatory Arrest in Pregnancy Enio Buffolo, MD, J. Honorio Palma, MD, Walter J. Gomes, MD, Herminie Vega, MD, Daniel Born, MD, Antonio F. Moron, MD, and Antonio C. Carvalho, MD Divisions of Cardiovascular Surgery, Cardiology, and Obstetrics, Escola Paulista de Medicina, Sao Paulo, Brazil

A woman pregnant for 21 weeks underwent an emergency operation because of an aortic arch aneurysm that had ruptured into her left lung. Cardiopulmonary bypass and deep hypothermia were used and she needed 37 minutes of circulatory arrest at a core temperature of 19°C. Both the mother and fetus survived, and a normal baby was delivered by cesarean section at the 39th week of gestation. (Ann Thorae Surg 1994;58:1532-4)

D

eep hypothermic circulatory arrest with cardiopulmonary bypass has been utilized in the surgical treatment used for several cardiac diseases or malformations [1]. However, reports of the use of deep hypothermic circulatory arrest in pregnant women are extremely rare. Even the role of hypothermia in heart operations during pregnancy is still controversial [2]. We report the case of a pregnant patient who required an emergency operation using deep hypothermic circulatory arrest for repair of a ruptured aortic arch aneurysm stemming from Takayasu's arteritis. Both the fetus and mother survived. A 28-year-old woman in her 21st week of pregnancy was referred to the Sao Paulo Hospital of the Escola Paulista de Medicina because of back pain that radiated to the precordium and left shoulder. Two days before admission, she had a diffuse chest pain, followed by hemoptysis, dizziness, and syncope. On admission the patient was pale Accepted for publication March 26, 1994. Address reprint requests to Dr Buffolo, Rua Napoleao de Barros 715, 3° andar-04024-000 Sao Paulo, SP Brazil.

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Fig 1. Preoperative x-ray study showing a large aortic arch aneurysm in the upper left hemithorax.

2+ /4+, her pulse rate was 92 beats/min, and her blood pressure was 100/60 mm Hg. Cardiac auscultation revealed a rough mesosystolic murmur over the upper left sternal border. Abdominal examination revealed no organomegaly and the uterine fundus was at the level of the umbilicus. Fetal heartbeats were normal. A chest x-ray study revealed marked enlargement of the superior mediastinum (Fig 1). Laboratory test results were as follows: hemoglobin, 9.2 g/ dL; hematocrit, 25%; white blood cells, 19,200/ [.LL; and creatinine, 0.4 mg/dL. Electrocardiographic findings were unremarkable. Bronchoscopy revealed fresh blood and clots in the apicoposterior segment of the left superior pulmonary lobe. Echocardiography showed an aneurysmal saccular formation in the transverse aorta and thoracoabdominal transition area. Fetal echographic findings were normal. Despite medical treatment, the hemoptysis episodes recurred and the patient's condition deteriorated. Angiography performed with abdominal protection revealed subocclusion of the innominate artery at its origin, an aneurysm at the posterior wall of the transverse aorta, a saccular aneurysm of the descending aorta just beyond the take off of the left subclavian artery, and another small saccular aneurysm in the thoracoabdominal transition area (juxtadiaphragmatic), Because of the imminent risk of aneurysm rupture, a multidisciplinary consultation was carried out and surgical treatment was decided upon. Before induction of anesthesia, fetal monitoring with cardiotocography was instituted. Operation was performed through a median sternotomy using cardiopulmonary bypass and 19°C deep hypothermic circulatory arrest. A bubble oxygenator was used (Tecnobio, Sao Paulo, Brazil) without pulsatile flow. The mean bypass flow rate was 2.4 L· min-- 1 • m- 2 and the mean perfusion pressure was 60 mm Hg. Upon reaching a temperature of 24°C, loss of the fetal heartbeat was noted, followed soon afterward by dislodgement of the cardiotocography sensor, ruling out its further use in the intraoperative period. At a core temperature of 19°C, cardiopulmonary bypass was interrupted.

CASE REPORT BUFFOLO ET AL HYPOTHERMIC CIRCULATORY ARREST IN PREGNANCY

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After a longitudinal incision was made in the transverse aorta, two aneurysmal entrance holes were visualized, one just distal to the left subclavian artery ostium and the other beneath the transition of the left carotid and the left subclavian arteries. These were closed with a single pericardial patch and running suture. A bypass graft between the ascending aorta and innominate artery was also necessary to treat the subocclusion; this was done using a Gore-Tex patch (W.L. Gore, Elkton, MD). At the end of the procedure, the patient was rewarmed, heart activity resumed spontaneously, and cardiopulmonary bypass was discontinued uneventfully. The total bypass time was 120 minutes and the circulatory arrest time was 37 minutes. The patient was taken back to the surgical intensive care unit, where return of the fetal heartbeat was observed. The patient's postoperative course was uneventful, except for the development of premature labor, which resolved after the intravenous administration of terbutaline. The patient was discharged on the 12th postoperative day and was taking prednisone (50 mg/day). Examination of aortic fragments revealed a chronic inflammatory process that was compatible with Takayasu's arteritis. At the 39th week of gestation, a normal baby weighing 2,650 g was delivered by cesarean section. Medical and laboratory investigations confirmed the baby was healthy. The child is now 2 years old, and both somatic and psychomotor development have been normal.

Comment The use of hypothermia in pregnant women is questionable, as the risks and benefits of hypothermia to the fetus are controversial. Even its proponents recommend moderate hypothermia of between 30° to 34°C [2]. Hypothermia can induce acid-base alterations, coagulation disorders, arrhythmias, and ventricular fibrillation, and can precipitate uterine contractions. Rewarming can also precipitate uterine contractions, leading to premature labor [3]. Heart operations involving circulatory arrest performed during pregnancy have already been discussed in the medical literature. Daley and co-workers [4] in 1957 reported employing 32°C surface cooling and 3 minutes of circulatory arrest for the relief of congenital pulmonary valve stenosis in a pregnant woman at 3 months' gestation. Strickland and associates [3] reported the use of circulatory arrest with cardiopulmonary bypass lasting 16 minutes at a core temperature of 24°C for repair of tetralogy of Fallot in a pregnant patient at 8 weeks' gestation. In both cases, the mothers and fetuses survived. Open heart surgical procedures in pregnant patients have been accomplished at temperatures ranging from 22° to 37°C, with subsequently successful pregnancies. However, unsuccessful cases have also been reported, indicating some gestational age-related risk for the tolerance of hypothermia. It has been proposed that hypothermia might protect the fetus by reducing the fetal oxygen requirements [3]. Deep hypothermia and a long circulatory arrest time were employed in our patient. The occurrence of Takayasu's arteritis during pregnancy is uncommon and may have deleterious consequences. It

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CASE REPORT McMANUS ET AL LIPOTHYMOMA WITH RED CELL APLASIA

requires meticulous and aggressive management for pregnancy to be successful [5]. Surgical intervention in our patient was mandatory, and the fetus's survival was unexpected, as we could not get an estimate from the literature regarding the prospects for fetal survival in the setting of deep hypothermic circulatory arrest. Experimental studies in this area are needed to answer some of the questions posed by our case and to improve our knowledge so that the risk for both the mother and fetus can be reduced.

References 1. Davis EA, Gillinov AM, Cameron DE, Reitz BA. Hypothermic circulatory arrest as a surgical adjunct: a 5-year experience with 60 adult patients. Ann Thorac Surg 1992;53:402-7. 2. Becker RM. Intracardiac surgery in pregnant women. Ann Thorac Surg 1983;36:453-8. 3. Strickland RA, Oliver WC [r, Chantigian RC, Ney JA, Danielson GK. Anesthesia, cardiopulmonary bypass, and the pregnant patient. Mayo Clin Proc 1991;66:411-29. 4. Daley R, Harrison GK, McMillan IKR. Direct-vision pulmonary valvotomy during pregnancy. Lancet 1957;273:875-6. 5. Craca LM, Cardoso MC, Machado FS. Takayasu's arteritis and pregnancy: a case of deleterious association. Eur J Obstet Gynecol Reprod Bioi 1987;24:347-51.

Lipothymoma With Red Cell Aplasia, Hypogammaglobulinemia, and Lichen Planus Kieran G. McManus, MD, Mark S. Allen, MD, Victor F. Trastek, MD, Claude Deschamps, MD, Thomas B. Crotty, MD, and Peter C. Pairolero, MD Section of General Thoracic Surgery and Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota

We describe a patient who had lipothymoma with red cell aplasia, hypogammaglobulinemia, and lichen planus. Parathymic syndromes described in association with lipothymomas also include myasthenia gravis, hyperthyroidism, lymphangioma, aplastic anemia, chronic lymphocytic leukemia, and Hodgkin's disease. The behavior of lipothymoma is generally benign, although local recurrence was noted in 1 patient who had an incomplete resection. Lipothymoma should be considered in the diagnosis of mediastinal tumors and parathymic syndromes, and also in patients with cardiomegaly, phrenic nerve palsy, and a widened mediastinum. (Ann Thorae Surg 1994;58:1534-6)

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ip othym oma is an uncommon fatty tumor of the thymus. Its origin is unclear, though some have suggested it is a mixed mesenchymal and entodermal tumor Accepted for publication March 28, 1994. Address reprint requests to Dr Allen, Mayo Clinic, 200 First St SW, Rochester, MN 55905.

© 1994 by The Society of Thoracic Surgeons

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occurring in the thymus [1]. Lipothymomas have been associated with myasthenia gravis and other parathymic syndromes such as hyperthyroidism [2], lymphangioma [3], aplastic anemia [4], Hodgkin's disease, hypogammaglobulinemia, and chronic lymphocytic leukemia [5]. We describe a patient who had a lipothymoma together with lichen planus, red cell aplasia, and hypogammaglobulinemia, three conditions known to be associated with thymoma. A 41-year-old man was referred for the management of "chronic sinusitis." Chest roentgenography revealed a large opacity in the right hemithorax (Fig 1). Further questioning of the patient revealed a history of breathlessness on moderate to severe exertion since the age of 14 years. Chest roentgenograms in the past had revealed what was thought to be an elevated hemidiaphragm. A computed tomographic scan of the thorax obtained at this admission showed a low-density mass involving both lobes of the thymus and extending into the right hemithorax (Fig 2). Physical examination revealed lichen planus of the buccal mucosa and decreased breath sounds on the right. The preoperative hemoglobin concentration was 11.2 g/dL, leukocyte count, 5.8 X 103/L; platelet count, 294 X 106/L; and mean corpuscular volume, 91.1 fl. The tumor was resected through a median sternotomy. It weighed 3.7 kg and measured 42 X 23 X 10 cm. It was bilobed and did not invade other intrathoracic structures. Blood loss during the procedure was minimal. Histologically, the tumor was composed of a mixture of benign, mature adipose tissue and unremarkable thymic tissue. The thymic tissue, which showed pronounced involution of both the lymphoid and epithelial elements, constituted approximately 5% of the tumor volume. Lymphoid follicles were absent, and Hassall's corpuscles were scarce (Fig 3). The hemoglobin level on the fourth postoperative day was 5.8 g/ dL. There was no evidence of hemorrhage from the incision, chest tubes, or gastrointestinal or genitourinary tract. The computed tomographic scan of the chest and abdomen revealed no hematoma. There was no evidence of hemolysis. A bone marrow biopsy specimen showed virtually no erythrocyte precursors, a finding consistent with pure red cell aplasia. Immunoelectrophoresis demonstrated a specific deficiency of gamma globulins: immunoglobulin G, 540 mg/dL (normal, 700 to 1,500 mg/ dl.): immunoglobulin M, 93.6 mg/ dL (normal, 60 to 300 mg/dL), and immunogloblin A, 170 mg/dL (normal, 60 to 400 mg/dL). After the transfusion of six units of packed red blood cells, the hemoglobin level increased to 11.9 g/ dL. After discharge from the hospital, the patient remained transfusion dependent, requiring 21 units of red blood cells despite a 2-month trial of corticosteroids. He was subsequently given cyclosporine, and within a month the hemoglobin level rose to 10.9 g/ dL without the need for further transfusion. He remains well on a regimen of 500 mg of cyclosporine a day. 0003-4975/94/$7.00