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Surgical management of extensive lipomatous hypertrophy of the right atrium
Cardiovascular Surgery, Vol. 8, No. 1, pp. 88–90, 2000 2000 The International Society for Cardiovascular Surgery. Published by Elsevier Science Ltd All rights reserved. Printed in Great Britain 0967–2109/00 $20.00
PII: S0967-2109(99)00080-0
www.elsevier.com/locate/cardiosur
Surgical management of extensive lipomatous hypertrophy of the right atrium S. Christiansen*, J. Stypmann†, H.A. Baba‡, D. Hammel* and H.H. Scheld* *Department of Thoracic, Cardiac and Vascular Surgery, Westphalian Wilhelms-University of Mu¨nster, Albert-Schweitzer-Str. 33, D-48149 Mu¨nster, Germany and †Department of Cardiology and Angiology, Westphalian Wilhelms-University of Mu¨nster, Albert-Schweitzer-Str. 33, D-48149 Mu¨nster, Germany and ‡Gerhard-Domagk-Institute of Pathology, Westphalian Wilhelms-University of Mu¨nster, Albert-Schweitzer-Str. 33, D-48149 Mu¨nster, Germany Lipomatous hypertrophy of the right atrium is a rare lesion that is usually limited to the interatrial septum. The authors report on a patient that suffered from an extensive lipomatous hypertrophy, which protruded into the right and left atrium as well as the superior vena cava and caused inflow obstruction. Therapeutic management is discussed. 2000 The International Society for Cardiovascular Surgery. Published by Elsevier Science Ltd. All rights reserved Keywords: cardiac surgery, cardiac tumours, lipomatous hypertrophy
Introduction This article describes an unusual case of lipomatous hypertrophy. This lesion is usually limited to the interatrial septum [1], but in the authors’ patient the right atrium was almost completely filled with the tumour, and caused a marked narrowing of the cavoatrial junction. Additionally, the roof of the left atrium was also involved. Lipomatous hypertrophy of the right atrium was first described by Prior [2] and is defined as a fatty infiltration > 2 cm thick in the interatrial septum [3]. It consists of multivacuolated fat cells with interspersed myocytes and, in contrast to lipoma, lacks a capsule [3].
1). Cardiac catheterization demonstrated moderately impaired left ventricular function, and coronary artery disease was excluded. The lesion was suspected to be a myxoma and surgical resection was performed. After sternotomy, a thickening of the right atrial
Case report A 64-year-old female patient, who was mildly overweight (body mass index: 26 kg/m2), suffered from syncopes of unclear origin. She did not report shortness of breath, cardiac arrhythmias or angina pectoris. The electrocardiogram showed sinus rhythm with a heart rate of 96 beats per minute. A thickening of the interatrial septum that protruded into the right atrium was diagnosed echocardiographically (Figure
Correspondence to: Dr S. Christiansen
88
Figure 1 A transoesophageal four-chamber view of the tumour. It has clear margins, a broad attachment to the intra-atrial septum and is partly calcified. The region of the foramen ovale appears tumour-free. The tumour is echo-richer and more echo-inhomogenic in comparison to the myocardium. LA, left atrium; LV, left ventricle; IVS, intraventricular septum; RV, right ventricle; TU, tumour; RA, right atrium
CARDIOVASCULAR SURGERY JANUARY 2000 VOL 8 NO 1
Surgical management of extensive lipomatous hypertrophy of the right atrium: S. Christiansen et al.
wall > 2 cm and an inflow obstruction (diameter ⬍ 5 mm) of the superior vena cava by the tumour was diagnosed. Extracorporeal circulation was instituted via the ascending aorta, the superior vena cava at a distance from the tumour and the inferior vena cava. The superior vena cava was dissected 2 cm above the cavo-atrial junction and resected en bloc with parts of the right atrium, the interatrial septum and the roof of the left atrium. Reconstruction of the atria was performed by using a Dacron-patch (Vascutek, Inchinnan, Renfrewshire, UK). The resected part of the superior vena cava was replaced by a 14-mm Gore-Tex prosthesis (Gore and Associates, Flagstaff, AR) and anastomosed to the reconstructed right atrium. The duration of surgery, extracorporeal circulation and X-clamping lasted 210, 110 and 62 min, respectively. At 7 hours postoperatively the patient was weaned from mechanical ventilation. The mediastinal chest tubes were removed on the 2nd postoperative day after a total drainage of 610 ml. Pacemaker stimulation was necessary during the first 2 postoperative days because of a bradyarrhythmia absoluta, which was probably caused by the resection of the sinus node and crista terminalis. On the 3rd postoperative day the patient developed a tachyarrhythmia absoluta, which converted into a stable atrial fibrillation after treatment with verapamil and digoxin. Holter monitoring did not reveal any further bradyarrhythmias, and so a pacemaker implantation was unnecessary. The patient was discharged on the 14th postoperative day and is still alive 9 months after surgery, and has experienced no recurrence of symptoms. Histologic examination revealed a diagnosis of lipomatous hypertrophy without evidence of malignancy (Figure 2).
Discussion Patients suffering from lipomatous hypertrophy are often asymptomatic [4]. However, congestive heart failure, atrial fibrillation, supraventricular tachycardia, palpitations and syncopes are typical findings with cardiac arrhythmias and are seen in ~50% of all affected patients [3, 5]. Malignant degeneration of lipomatous hypertrophy has been discussed in one case report, but has not been proven until now [6]. It usually occurs between the ages of 70–80 years; it is almost exclusively restricted to the interatrial septum and rarely produces significant obstruction [1, 5, 7]. The patient, described in the case report by McNamara et al. [1], developed progressive acidosis, hypoxia, oliguria and hypotension refractory to resuscitation and died before diagnosis was made. Autopsy showed a recent thrombosis of both the circumflex and right coronary arteries; however, it revealed a 3 ⫻ 3 cm mass that encircled the superior right atrium with minimal thickening of the superior interatrial septum, but marked narrowing of the cavoatrial junction. Retrospectively considered, it is probable that this patient died because of myocardial infarction. Another patient, described by Scully et al. [7], suffered from exertional dyspnea and palpitations, as well as attacks of atrial fibrillation. The diagnosis of lipomatous hypertrophy, which caused obstruction of the orifice of the superior vena cava, was made by computed tomography and magnetic resonance imaging, and the patient underwent successful resection of the tumour. Surgical resection of the tumour was performed on the authors’ patient because it was suspected to be a myxoma, but histological examination revealed a diagnosis of lipomatous hypertrophy. To avoid misdiagnosis, as for the authors’ patient, it is worth noting that lipomatous hypertrophy may be diagnosed preoperatively by computed tomography, magnetic resonance imaging or by nuclear magnetic resonance imaging, as described by Scully et al. [7] and Levine et al. [8]. In all, lipomatous hypertrophy may be an important differential diagnosis of myxoma, which may present an unusual extension and can be diagnosed by non-invasive procedures preoperatively.
References
Figure 2 Surgically resected part of the septum. Histology reveals massive infiltration of mature fat cells with remnants of cardiomyocytes intermingled with vacuolated, multiglobular fat cells. Haematoxylin and eosin stain, ⫻ 250
CARDIOVASCULAR SURGERY
JANUARY 2000 VOL 8 NO 1
1. McNamara, R.F., Taylor, A.E. and Panner, B.J., Superior vena caval obstruction by lipomatous hypertrophy of the right atrium. Clinical Cardiology, 1987, 10, 609–610. 2. Prior, J.T., Lipomatous hypertrophy of cardiac interatrial septum. A lesion resembling hibernoma, lipoblastomatosis and infiltrating lipoma. Archives of Pathology, 1964, 78, 11–15. 3. Burke, A.P., Litovsky, S. and Virmani, R., Lipomatous hypertrophy of the atrial septum presenting as a right atrial mass. American Journal of Surgical Pathology, 1996, 20, 678–685. 4. Acker, M. A. and Gardner, T. J., Cardiac tumours. In Glenn’s
89
Surgical management of extensive lipomatous hypertrophy of the right atrium: S. Christiansen et al. Thoracic and Cardiovascular Surgery, 6th edn, ed. A. E. Baue, A. S. Geha, G. L. Hammond, H. Laks and K. S. Naunheim. Appleton and Lange, Stamford, Connecticut, 1995, pp. 2311–2325. 5. Castleman, B. and McNeely, B.U., Case records of the Massachusetts General Hospital (Case 43-1971). Liposarcoma of interatrial septum and both atria. New England Journal of Medicine, 1971, 285, 1016–1023. 6. Reyes, C.V. and Jablokow, V.R., Lipomatous hypertrophy of the atrial septum: a report of 38 cases and review of the literature. American Journal of Clinical Pathology, 1979, 72, 785–788.
90
7. Scully, R.E., Mark, E.J., McNeely, W.F. and McNeely, B.U., Case records of the Massachusetts General Hospital. New England Journal of Medicine, 1989, 320, 652–660. 8. Levine, R.A., Weyman, A.E., Dinsmore, R.E. et al., Noninvasive tissue characterization: diagnosis of lipomatous hypertrophy of the atrial septum by nuclear magnetic resonance imaging. Journal of the American CC, 1986, 7, 688–692. Paper accepted 17 August 1999
CARDIOVASCULAR SURGERY JANUARY 2000 VOL 8 NO 1
PII: S0967-2109(99)00080-0
www.elsevier.com/locate/cardiosur
Surgical management of extensive lipomatous hypertrophy of the right atrium S. Christiansen*, J. Stypmann†, H.A. Baba‡, D. Hammel* and H.H. Scheld* *Department of Thoracic, Cardiac and Vascular Surgery, Westphalian Wilhelms-University of Mu¨nster, Albert-Schweitzer-Str. 33, D-48149 Mu¨nster, Germany and †Department of Cardiology and Angiology, Westphalian Wilhelms-University of Mu¨nster, Albert-Schweitzer-Str. 33, D-48149 Mu¨nster, Germany and ‡Gerhard-Domagk-Institute of Pathology, Westphalian Wilhelms-University of Mu¨nster, Albert-Schweitzer-Str. 33, D-48149 Mu¨nster, Germany Lipomatous hypertrophy of the right atrium is a rare lesion that is usually limited to the interatrial septum. The authors report on a patient that suffered from an extensive lipomatous hypertrophy, which protruded into the right and left atrium as well as the superior vena cava and caused inflow obstruction. Therapeutic management is discussed. 2000 The International Society for Cardiovascular Surgery. Published by Elsevier Science Ltd. All rights reserved Keywords: cardiac surgery, cardiac tumours, lipomatous hypertrophy
Introduction This article describes an unusual case of lipomatous hypertrophy. This lesion is usually limited to the interatrial septum [1], but in the authors’ patient the right atrium was almost completely filled with the tumour, and caused a marked narrowing of the cavoatrial junction. Additionally, the roof of the left atrium was also involved. Lipomatous hypertrophy of the right atrium was first described by Prior [2] and is defined as a fatty infiltration > 2 cm thick in the interatrial septum [3]. It consists of multivacuolated fat cells with interspersed myocytes and, in contrast to lipoma, lacks a capsule [3].
1). Cardiac catheterization demonstrated moderately impaired left ventricular function, and coronary artery disease was excluded. The lesion was suspected to be a myxoma and surgical resection was performed. After sternotomy, a thickening of the right atrial
Case report A 64-year-old female patient, who was mildly overweight (body mass index: 26 kg/m2), suffered from syncopes of unclear origin. She did not report shortness of breath, cardiac arrhythmias or angina pectoris. The electrocardiogram showed sinus rhythm with a heart rate of 96 beats per minute. A thickening of the interatrial septum that protruded into the right atrium was diagnosed echocardiographically (Figure
Correspondence to: Dr S. Christiansen
88
Figure 1 A transoesophageal four-chamber view of the tumour. It has clear margins, a broad attachment to the intra-atrial septum and is partly calcified. The region of the foramen ovale appears tumour-free. The tumour is echo-richer and more echo-inhomogenic in comparison to the myocardium. LA, left atrium; LV, left ventricle; IVS, intraventricular septum; RV, right ventricle; TU, tumour; RA, right atrium
CARDIOVASCULAR SURGERY JANUARY 2000 VOL 8 NO 1
Surgical management of extensive lipomatous hypertrophy of the right atrium: S. Christiansen et al.
wall > 2 cm and an inflow obstruction (diameter ⬍ 5 mm) of the superior vena cava by the tumour was diagnosed. Extracorporeal circulation was instituted via the ascending aorta, the superior vena cava at a distance from the tumour and the inferior vena cava. The superior vena cava was dissected 2 cm above the cavo-atrial junction and resected en bloc with parts of the right atrium, the interatrial septum and the roof of the left atrium. Reconstruction of the atria was performed by using a Dacron-patch (Vascutek, Inchinnan, Renfrewshire, UK). The resected part of the superior vena cava was replaced by a 14-mm Gore-Tex prosthesis (Gore and Associates, Flagstaff, AR) and anastomosed to the reconstructed right atrium. The duration of surgery, extracorporeal circulation and X-clamping lasted 210, 110 and 62 min, respectively. At 7 hours postoperatively the patient was weaned from mechanical ventilation. The mediastinal chest tubes were removed on the 2nd postoperative day after a total drainage of 610 ml. Pacemaker stimulation was necessary during the first 2 postoperative days because of a bradyarrhythmia absoluta, which was probably caused by the resection of the sinus node and crista terminalis. On the 3rd postoperative day the patient developed a tachyarrhythmia absoluta, which converted into a stable atrial fibrillation after treatment with verapamil and digoxin. Holter monitoring did not reveal any further bradyarrhythmias, and so a pacemaker implantation was unnecessary. The patient was discharged on the 14th postoperative day and is still alive 9 months after surgery, and has experienced no recurrence of symptoms. Histologic examination revealed a diagnosis of lipomatous hypertrophy without evidence of malignancy (Figure 2).
Discussion Patients suffering from lipomatous hypertrophy are often asymptomatic [4]. However, congestive heart failure, atrial fibrillation, supraventricular tachycardia, palpitations and syncopes are typical findings with cardiac arrhythmias and are seen in ~50% of all affected patients [3, 5]. Malignant degeneration of lipomatous hypertrophy has been discussed in one case report, but has not been proven until now [6]. It usually occurs between the ages of 70–80 years; it is almost exclusively restricted to the interatrial septum and rarely produces significant obstruction [1, 5, 7]. The patient, described in the case report by McNamara et al. [1], developed progressive acidosis, hypoxia, oliguria and hypotension refractory to resuscitation and died before diagnosis was made. Autopsy showed a recent thrombosis of both the circumflex and right coronary arteries; however, it revealed a 3 ⫻ 3 cm mass that encircled the superior right atrium with minimal thickening of the superior interatrial septum, but marked narrowing of the cavoatrial junction. Retrospectively considered, it is probable that this patient died because of myocardial infarction. Another patient, described by Scully et al. [7], suffered from exertional dyspnea and palpitations, as well as attacks of atrial fibrillation. The diagnosis of lipomatous hypertrophy, which caused obstruction of the orifice of the superior vena cava, was made by computed tomography and magnetic resonance imaging, and the patient underwent successful resection of the tumour. Surgical resection of the tumour was performed on the authors’ patient because it was suspected to be a myxoma, but histological examination revealed a diagnosis of lipomatous hypertrophy. To avoid misdiagnosis, as for the authors’ patient, it is worth noting that lipomatous hypertrophy may be diagnosed preoperatively by computed tomography, magnetic resonance imaging or by nuclear magnetic resonance imaging, as described by Scully et al. [7] and Levine et al. [8]. In all, lipomatous hypertrophy may be an important differential diagnosis of myxoma, which may present an unusual extension and can be diagnosed by non-invasive procedures preoperatively.
References
Figure 2 Surgically resected part of the septum. Histology reveals massive infiltration of mature fat cells with remnants of cardiomyocytes intermingled with vacuolated, multiglobular fat cells. Haematoxylin and eosin stain, ⫻ 250
CARDIOVASCULAR SURGERY
JANUARY 2000 VOL 8 NO 1
1. McNamara, R.F., Taylor, A.E. and Panner, B.J., Superior vena caval obstruction by lipomatous hypertrophy of the right atrium. Clinical Cardiology, 1987, 10, 609–610. 2. Prior, J.T., Lipomatous hypertrophy of cardiac interatrial septum. A lesion resembling hibernoma, lipoblastomatosis and infiltrating lipoma. Archives of Pathology, 1964, 78, 11–15. 3. Burke, A.P., Litovsky, S. and Virmani, R., Lipomatous hypertrophy of the atrial septum presenting as a right atrial mass. American Journal of Surgical Pathology, 1996, 20, 678–685. 4. Acker, M. A. and Gardner, T. J., Cardiac tumours. In Glenn’s
89
Surgical management of extensive lipomatous hypertrophy of the right atrium: S. Christiansen et al. Thoracic and Cardiovascular Surgery, 6th edn, ed. A. E. Baue, A. S. Geha, G. L. Hammond, H. Laks and K. S. Naunheim. Appleton and Lange, Stamford, Connecticut, 1995, pp. 2311–2325. 5. Castleman, B. and McNeely, B.U., Case records of the Massachusetts General Hospital (Case 43-1971). Liposarcoma of interatrial septum and both atria. New England Journal of Medicine, 1971, 285, 1016–1023. 6. Reyes, C.V. and Jablokow, V.R., Lipomatous hypertrophy of the atrial septum: a report of 38 cases and review of the literature. American Journal of Clinical Pathology, 1979, 72, 785–788.
90
7. Scully, R.E., Mark, E.J., McNeely, W.F. and McNeely, B.U., Case records of the Massachusetts General Hospital. New England Journal of Medicine, 1989, 320, 652–660. 8. Levine, R.A., Weyman, A.E., Dinsmore, R.E. et al., Noninvasive tissue characterization: diagnosis of lipomatous hypertrophy of the atrial septum by nuclear magnetic resonance imaging. Journal of the American CC, 1986, 7, 688–692. Paper accepted 17 August 1999
CARDIOVASCULAR SURGERY JANUARY 2000 VOL 8 NO 1