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CASE REPORT HARADA ET AL RIGHT ATRIAL ISOLATION
Right Atrial Isolation for Atrial Fibrillation Associated With Atrial Septal Defect Atsushi Harada, MD, Takao Ida, MD, and Masatoshi Ikeshita, MD Division of Cardiac Surgery, Sakakibara Heart Institution, and Second Department of Surgery, Division of Thoracic and Cardiovascular Surgery, Nippon Medical School, Tokyo, Japan
Two patients with atrial fibrillation associated with an atrial septal defect underwent simultaneous surgical correction of the atrial septal defect and right atrial isolation. The right atrium was surgically isolated while the continuity with the sinoatrial node was preserved in the remainder of the heart. After the operation, the patients maintained normal sinus rhythm for 99 and 65 months. Thus, right atrial isolation offers an alternative to the current surgical treatment for atrial fibrillation associated with an atrial septal defect. (Ann Thorac Surg 1998;65:1766 – 8) © 1998 by The Society of Thoracic Surgeons
Ann Thorac Surg 1998;65:1766 – 8
The fractionated potentials indicating arrhythmogenicity of AF were recorded from the right atrial epicardium just lateral to the sulcus terminalis (Fig 1). After the institution of total cardiopulmonary bypass, the aorta was cross-clamped and the heart was arrested with crystalloid cardioplegia. The initial right atriotomy was placed between the sulcus terminalis and the site of the fractionated potentials. The right atriotomy was extended cephalad and caudad, and the body of the right atrium was excluded by an encircling surgical incision. Then, cryolesions (260°C for 3 minutes) were placed at the end of the incision to sever all atrial fibers at the level of the tricuspid valve annulus (Fig 2). The ASD secundum was then closed with a polytetrafluoroethylene patch, and the atrial incision was subsequently closed with a continuous suture. After the aortic clamp was released, the patient maintained sinus rhythm and was weaned from cardiopulmonary bypass without the use of artificial pacing. The patient has maintained normal sinus rhythm without any antiarrhythmic agents for 99 months after the operation.
Patient 2
he right atrial isolation procedure [1] was developed under the direction of Cox at Washington University. This procedure alleviates the detrimental effects of all supraventricular arrhythmias arising in the right atrium. Atrial fibrillation (AF) associated with an atrial septal defect (ASD) in adult patients may arise from the body of the dilated right atrium induced by chronic volume overload. Therefore, isolation of the right atrium could confine arrhythmogenicity of AF to the body of the right atrium and restore normal sinus rhythm in the remainder of the heart.
A 39-year-old man was diagnosed with ASD secundum and transient AF. A preoperative electrophysiologic study revealed that the AF was sustained and induced by rapid atrial pacing. Intraoperative right atrial activation mapping was performed during sinus rhythm because the patient maintained sinus rhythm at the time of the operation. The site of earliest activation corresponded to the site of the anatomic sinoatrial node, and fractionated potentials were recorded from the body of the right atrium. With the same procedure as in patient 1, the right atrium was isolated and the sinoatrial node and sulcus terminalis were preserved in the remainder of the heart. The patient has maintained normal sinus rhythm without any antiarrhythmic agents for 65 months after the operation.
Case Reports
Postoperative Electrophysiologic Study
T
Patient 1 A 52-year-old woman was diagnosed with chronic AF and ASD secundum. Intracardiac repair of ASD and right atrial isolation to restore normal sinus rhythm were proposed. Under general anesthesia with fentanyl citrate, median sternotomy followed by a pericardiotomy was performed, revealing a dilated right atrium with markedly fibrous degeneration of its epicardium. Before institution of cardiopulmonary bypass, AF was converted to sinus rhythm with direct-current countershock, and right atrial activation mapping was performed. Two breakthroughs of sinus rhythm were observed, and the dominant one corresponded to the anatomic sinoatrial node. Accepted for publication Dec 13, 1997. Address reprint requests to Dr Harada, Department of Cardiovascular Surgery, Ebina General Hospital, 1519 Kawaraguchi Ebina-city, Kanagawa, Japan 243-0433.
© 1998 by The Society of Thoracic Surgeons Published by Elsevier Science Inc
Electrophysiologic examinations were performed 3 weeks after the operation in both patients. The isolated right atrium maintained a slow, irregular, intrinsic rhythm. Regular sinus rhythm with normal sinus node recovery time and normal atrioventricular conduction were demonstrated in the remainder of the heart. Right atrial tachycardia simulated by rapid pacing in the isolated right atrium was confined to the isolated right atrium. Sustained AF was not induced by rapid atrial pacing or an extrastimulus method.
Comment The maze procedure is a surgical method to treat AF [2] and was applied to treat AF associated with ASD by Cox, Bonchek, and their associates [2, 3]. In contrast to the complex maze procedure, right atrial isolation is simple and its effectiveness has been reported by Minzioni and associates [4]. We present our clinical experience of right 0003-4975/98/$19.00 PII S0003-4975(98)00169-6
Ann Thorac Surg 1998;65:1766 – 8
CASE REPORT HARADA ET AL RIGHT ATRIAL ISOLATION
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Fig 1. Right atrial activation map during converted sinus rhythm in patient 1. The dominant impulse origin corresponded to the anatomic sinoatrial node. Fractionated potentials, indicated by white arrows in the right panel, were recorded from the dotted area lateral to the sulcus terminalis. (ECG 5 electrocardiogram; IVC 5 inferior vena cava; LA 5 left atrium; MV 5 mitral valve; PV 5 pulmonary vein; RA 5 right atrium; RA Ref 5 right atrial reference electrogram; RAA 5 right atrial appendage; RV Ref 5 right ventricular reference electrogram; SVC 5 superior vena cava; TV 5 tricuspid valve.)
atrial isolation and the long-term results in this communication. Because a multichannel mapping system was not available at the time of the operation, atrial mapping with a hand-held electrode was performed only during sinus
Fig 2. Right atrial isolation. See text for details. (ASD 5 atrial septal defect; CS 5 coronary sinus; IVC 5 inferior vena cava; RA 5 right atrium; SN 5 sinus node; SVC 5 superior vena cava; TV 5 tricuspid valve.)
rhythm. Then, fractionated potentials were recorded from the body of the degenerated right atrium. Although the precise mechanism of the fractionated potentials was not known, there is a well-documented relationship between fractionated potentials and arrhythmia. Therefore, we excluded the degenerated right atrium in which the fractionated potentials were recorded. To maintain a physiologic sinus rhythm, the area of the earliest activation site, including the sinoatrial node identified by intraoperative mapping, was preserved in the remainder of the heart. Preservation of the sinus node artery is also required to maintain sinus rhythm [1]. The surgical incision for right atrial isolation was designed to preserve the sinus node artery identified by preoperative coronary angiography. The arrhythmogenicity in the isolated right atrium may not always discharge, and its mass may not be enough to maintain AF. Therefore, a slow intrinsic rhythm, instead of fibrillation, may be observed in the isolated right atrium at the time of the postoperative electrophysiologic study. A previous experimental hemodynamic study of right atrial isolation [5] demonstrated that the procedure does not adversely affect cardiac hemodynamics, despite the loss of synchronous right atrial contractions during sinus rhythm. The 2 patients have maintained normal sinus rhythm and stable hemodynamics corresponding to New York Heart Association class I. Therefore, right atrial isolation is feasible in the human heart, as in the canine heart, and this technique should
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CASE REPORT PEACHELL ET AL BIATRIAL MYXOMA
Ann Thorac Surg 1998;65:1768 –9
be the procedure of choice for the management of AF arising in the right atrium.
References 1. Harada A, D’Agostino HJ Jr, Schuessler RB, Boineau JP, Cox JL. Right atrial isolation: a new surgical treatment for supraventricular tachycardia. I. Surgical technique and electrophysiologic effects. J Thorac Cardiovasc Surg 1988;95:643–50. 2. Cox JL, Boineau JP, Schuessler RB, Kater KM, Lappas DG. Five-year experience with the maze procedure for atrial fibrillation. Ann Thorac Surg 1993;56:814–24. 3. Bonchek LI, Burlingame MW, Worley SJ, Vazales BE, Lundy EF. Cox/maze procedure for atrial septal defect with atrial fibrillation: management strategies. Ann Thorac Surg 1993;55: 607–10. 4. Minzioni A, Graffigna A, Pagani F, Vigano M. Right atrial isolation with atrial septal closure in patients with atrial septal defect and chronic atrial fibrillation. Cardiovasc Surg 1993;1: 666–9. 5. Harada A, D’Agostino HJ Jr, Boineau JP, Cox JL. Right atrial isolation: a new surgical treatment for supraventricular tachycardia. II. Hemodynamic effects. J Thorac Cardiovasc Surg 1988;95:651–7.
Biatrial Myxoma: A Rare Cardiac Tumor John L. Peachell, MD, John C. Mullen, MD, Michael J. Bentley, BSc, and Dylan A. Taylor, MD Divisions of Cardiothoracic Surgery and Cardiology, University of Alberta, Edmonton, Alberta, Canada
A previously healthy 48-year-old man presented to the hospital with a transient ischemic attack. Echocardiography revealed a large left atrial tumor with a second tumor in the right atrium. Surgical excision revealed a large left atrial myxoma with extension through the interatrial septum into the right atrium. (Ann Thorac Surg 1998;65:1768 –9) © 1998 by The Society of Thoracic Surgeons
Fig 1. Transesophageal echocardiogram (basal horizontal view) demonstrating large left and smaller right atrial components of biatrial myxoma (M). (Ao 5 aorta; LA 5 left atrium; RA 5 right atrium; S 5 septum.)
had a 30 pack/year history of smoking. The results of a neurologic examination were normal, but a cardiovascular examination revealed a middiastolic murmur with diastolic “plop” (caused by the left atrial tumor dropping into the mitral valve during diastole). A computed tomographic scan of the head and carotid Doppler studies were normal. Echocardiography revealed a large left atrial tumor and smaller right atrial tumor (Fig 1). A magnetic resonance scan (Fig 2) was performed to exclude malignancy. Coronary angiography revealed normal coronary arteries. He was advanced for an urgent operation.
C
ardiac myxomas represent approximately 50% of all benign cardiac tumors, with left atrial myxomas accounting for more than 70% [1]. Biatrial myxomas are extremely rare [2]. We describe the successful management of a middle-aged man with a huge biatrial myxoma. A healthy 48-year-old man presented with a sudden transient ischemic attack manifested by loss of vision in his right eye, which resolved spontaneously after 2 hours. He had a single episode of seizure activity 12 years earlier, for which he had been given phenytoin. He also Accepted for publication Dec 16, 1997. Address reprint requests to Dr Mullen, Departments of Surgery and Pediatrics, University of Alberta Hospital, 2D2.18 WC Mackenzie Health Sciences Centre, 8440 112 St, Edmonton, Alberta, Canada T6G 2B7 (e-mail:
[email protected]).
© 1998 by The Society of Thoracic Surgeons Published by Elsevier Science Inc
Fig 2. Magnetic resonance scan showing biatrial myxoma (M) and lack of extracardiac extension. (Ao 5 aorta; LA 5 left atrium; LV 5 left ventricle; RA 5 right atrium; RV 5 right ventricle; S 5 septum.) 0003-4975/98/$19.00 PII S0003-4975(98)00206-9
