E anomaly in which there is abnormal downward displacement. Christiaan Barnard s Contribution to the Surgical Treatment of Ebstein s Malformation

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1 CLASSICS IN THORACIC SURGERY Christiaan Barnard s Contribution to the Surgical Treatment of Ebstein s Malformation James K. Kirklin, MD The University of Alabama at Birmingham, Birmingham, Alabama The pioneering surgical endeavors of Christiaan Barnard in human cardiac transplantation are well recognized. His contribution in the surgery of Ebstein s malformation has also been unique. In 1963, Barnard s classic paper on Surgical correction of Ebstein s malformation with prosthetic tricuspid valve presented his pioneering accomplishments in this complex cardiac malformation. (Ann Thorac Surg ) Surgical correction of Ebstein s ma 1 f <I r 111 at i o n w i t h prosthetic tricuspid valve C. N. HAKNAKD, M.D., M.MEI)., M.S., Pn.1). V. %HKIKE, M.B., M.Sc., PH.~). CAW TOWN, SOUTH AFRICA From the Departments of Surgery and Medicine. University of Cape Town, the Council /or Scientific and Industrial Hcsearclr Cardiotmscular- Pulmonary Research Croup. and the Cardiac Clinic. Groofe Schwur Iiospitnl bstein s malformation is a rare congenital cardiac E anomaly in which there is abnormal downward displacement of the septal and/or posterior tricuspid leaflets into the right ventricle. The presence of an atrial septal defect, the frequently severe tricuspid valve incompetence, and often debilitating supraventricular arrhythmias (occasionally associated with Wolff-Parkinson-White syndrome) produce the clinical syndromes in Ebstein s malformation that may require surgical intervention. In their classic 1963 publication [l], Barnard and Schrire clearly outlined in 2 case reports the classic indications for tricuspid valve operation in Ebstein s malformation. The first patient was a 2s-year-old boy with refractory right-sided heart failure and persistent cyanosis. At operation, the patent foramen ovale was closed and the severely malformed and incompetent tricuspid valve was excised. A low-flow University of Cape Town lenticular prosthesis molded in Ivalon was inserted. The second patient was a 25-year-old man who had refractory rightsided heart failure and atrial dysrhythmias. He also underwent successful tricuspid valve replacement with a Address reprint requests to Dr Kirklin, Department of Surgery, The University of Alabama at Birmingham, UAB Station, Birmingham, AL similar prosthetic valve. The atrial septum in this patient was intact. In both instances, Barnard and Schrire emphasized the importance of placing the valve sutures on the atrial side of the coronary sinus to avoid injury to the atrioventricular node and His bundle. They speculated that the atrialized right ventricle would not interfere with right ventricular output and correctly concluded that no adverse effects would result from coronary sinus blood draining directly into the right ventricle. The natural history of Ebstein s malformation is highly variable. When symptoms are present early in life, such as in the first patient reported by Barnard and Schrire, there is frequently severe cyanosis associated with an interatrial communication, marked right-sided congestive heart failure resulting from severe tricuspid incompetence and occasional stenosis, and marked cardiomegaly [2]. The survival in this group is poor. The majority of patients, however, do not have symptoms until childhood or early adulthood, frequently with mild dyspnea and easy fatigability. About 60% of patients in whom symptoms develop after the neonatal period survive 20 years or more [3], and more than half the patients greater than 25 years of age with Ebstein s malformation are in New York Heart Association class I or I1 [4] by The Society of Thoracic Surgeons /$3.50

2 148 CLASSICS KIRKLIN Ann Thorac Surg Morphology The morphology of Ebstein s malformation was lucidly described in Barnard and Schrire s classic article on tricuspid valve replacement. They clearly appreciated the great variability of this complex malformation and specifically referred to the anatomic details and surgical implications of the atrial septal defect, the tricuspid valve malformation, right ventricular size, the possibility of right ventricular outflow obstruction, and the potential physiologic consequences of the atrialized portion of the right ventricle. They also referred to the important morphologic abnormalities of the tricuspid valve itself, many of which have direct relevance for successful tricuspid valve reconstruction [5]. There is downward displacement of the septal and posterior leaflets into the right ventricle. The anterior leaflet is large and sail-like, which is necessary for a competent valve after reconstruction. There may be important interchordal space obliteration and adherence to the right ventricular wall, which may create some degree of tricuspid stenosis. The tricuspid annulus is usually enlarged. An atrialized portion of the right ventricle is present between the tricuspid annulus and the attachment of the septal and posterior leaflets, which may be aneurysmal and move paradoxically with right ventricular contractions. The diagnostic methodology for delineation of anatomic detail in Ebstein s malformation has gradually evolved since Barnard and Schrire s original report, which described the electrocardiographic, phonocardiographic, and angiocardiographic details. Currently two-dimensional echocardiography is particularly useful in elucidating the subtleties of tricuspid valve morphology that must be understood if valve reconstruction is planned [5-71. Management of the Tricuspid Valve in the Surgical Treatment of Ebstein s Malformation When operation is advised for Ebstein s malformation, the optimal management of the tricuspid valve and the atrialized portion of the right ventricle remain controversial in the current era, partly because of the variability of the tricuspid valve in this malformation, partly due to the limited experience gained by any one surgical group, and partly because of the delayed emergence of enthusiasm for reconstruction of the atrioventricular valves. Tricuspid valve replacement has been the preferred management of the incompetent tricuspid valve of Ebstein s malformation in some institutions [8]. Barnard and Schrire s original article describes the method that has become standard for tricuspid valve replacement in this entity. During implantation of the prosthetic valve, the suture line is brought posterior to the coronary sinus and atrioventricular node near the junction between the displaced septal leaflet and the anterior leaflet. In other areas, the suture line follows the actual tricuspid valve annulus (Fig 1) [l, 91. Based on a concept put forth by Hunter and Lillehei [lo], Hardy and colleagues [ll] reported successful correction of Ebstein s malformation with tricuspid reconstruction in a 42-year-old woman. Hardy and colleagues emphasized the importance of obliterating the atrialized portion of the right ventricle by transposing the displaced septal leaflet to the normal plane of the tricuspid valve and reducing the annular circumference. In the current era, Danielson and his colleagues at the Mayo Clinic have generated a large experience in valve reconstruction (Fig 2) as part of the repair of Ebstein s malformation [12]. They emphasized a standard surgical approach including (1) electrophysiologic localization of accessory bypass tracts in patients with ventricular preexitation, (2) closure of the atrial septal defect, (3) plication of the atrialized portion of the right ventricle, (4) plastic repair or replacement of the tricuspid valve, (5) correction of associated cardiac anomalies, and (6) excision of redundant right atrial wall. They reported tricuspid valve reconstruction in 81% of patients (n = 42) with a hospital mortality of 7%. Danielson and colleagues modification of Hardy and colleagues [ll] original description further underscored the importance of staying anterior and to the right of the coronary sinus with the annuloplasty sutures to avoid injury to the conduction system. More recently, Carpentier and colleagues [5] have reported a different method of reconstruction employing a longitudinal plication of the atrialized chamber with detachment and repositioning of the displaced portion of the tricuspid annulus (Fig 3). Carpentier and colleagues addressed the variability of this malformation by recommending modification of the basic repair depending on the details of tricuspid valve and right ventricular morphology: If the anterior leaflet is large and mobile without obliteration of interchordal spaces and with moderate displacement of the posterior and septal leaflets, a small atrialized chamber, and adequate right ventricular volume, then a plication of the annulus and adjacent right atrial wall is performed and the atrialized chamber is not plicated. A portion of the anterior and posterior leaflets is detached and repositioned at the level of the tricuspid annulus with additional support provided by a ring. If the displacement of the leaflets is more extensive, with a large, thin, noncontractile atrialized portion and small right ventricle, then the atrialized chamber is obliterated with a longitudinal plication. If there is restricted motion of the anterior leaflet with fibrous attachments to the right ventricle and obliteration of interchordal spaces, then extensive mobilization of the anterior leaflet, resection of fibrous bands, and fenestration of interchordal spaces is recommended before repositioning of the leaflets. Late Surgical Results Comparisons of the efficacy and durability of the various methods of managing the tricuspid valve in this entity have been confounded by the rarity and variability of this condition. After Barnard and Schrire s classic first description of tricuspid valve replacement, numerous authors [8, 13-15] have reported small series of such treatment. At

3 Ann Thorac Surg CLASSICS KIRKLIN 149 Fig 1. Replacement of the tricuspid valve and closure of the atrial septal defect in Ebstein s malformation, as originally described in Barnard and Schrire s historic article [I]. With exposure through an oblique right atriotomy, the downward displacement of the septal and posterior leaflets is illustrated, and the atrioventricular node is indicated adjacent to the commissure between the septal and anterior leaflets. The sutures for valve replacement are placed well posterior to the coronary sinus and membranous system. The remainder of the suture line then follows the actual tricuspid annulus. (Reproduced with permission from Bharati S, Lev M, Kirklin 1W. Cardiac surgery and the conduction system. New York: Churchill Livingstone, 1983:3.46.) The University of Alabama at Birmingham, for example, 24 patients underwent operation for Ebstein s malformation over a 14-year period, of whom only 16 had tricuspid valve replacement [8]. In one of the largest experiences, Mair and colleagues [ 161 from the Mayo Clinic reported 72 patients undergoing operation over a 12-year period, 80% undergoing tricuspid valve reconstruction. Carpentier and colleagues (51 repaired the tricuspid valve in 13 of 14 \ \ I A I B I C \\ Fig 2. Annuloplasty repair of tricuspid valve in Ebstein s malformation, as described by Danielson and Fuster (A) The atrialized portion of the ventricle is plicated with interrupted pledgeted mattress sutures (shown from the surgeon s viewpoint, with the patient s head to the left). The atrial septal defect has been closed with a patch. (B) An annuloplasty suture is placed to narrow the tricuspid annulus and includes the entire posterior leaflet. The coronary sinus marks the posterior and leftward extent of the annuloplasty, avoiding the area of the conduction system. (C) The completed repair allows the large anterior leaflet to function as a monocusp valve. (Reproduced with permission from Danielson GK, Fuster V. Surgical repair of Ebstein s anomaly. Ann Surg 1982;196: )

4 150 CLASSICS KIRKLIN Ann Thorac Surg Fig 3. Tricuspid valve repair using a longitudinal plication, as described by Carpentier and associates [5]. (1) Surgeon s view. (11) Anterior leaflet and adjacent posterior leaflet are detached from the annulus. (111) Longitudinal plication of right ventricle, tricuspid annulus, and right atrium. (ZV) Anterior and posterior leaflets are sutured to tricuspid annulus after clockwise rotation. (V) Prosthetic ring is inserted to reinforce repairs. Atrial septal defect is closed with a patch. (A = anterior leaflet; P = posterior leaflet; S = septal leaflet.) (Reproduced with permission from Carpentier A, Chauvaud s, Mace L, et al. A new reconstructive operation for Ebstein s anomaly of the tricuspid valve. ] Thorac Cardiovasc Surg 1988;96:92-101). patients operated on for Ebstein s malformation over a 6-year period. The intermediate-term results after tricuspid valve replacement as part of the corrective operation are generally good, with most patients remaining in NYHA class I or I1 after 2 to 10 years [8, 14, 161. The choice of prosthesis (heterograft or Starr-Edwards valve) has not made an apparent difference in long-term results. In the experience of Mair and associates [16] and Carpentier and colleagues [5], at a mean follow-up of 3 to 5 years, greater than 80% of patients remain in NYHA class I or I1 after valve reconstruction. The vast majority of patients reported by these two groups have normal valve function with minimal incompetence on follow-up two-dimensional echocardiographic studies. In general, patients undergoing tricuspid valve replacement or repair as part of the correction of Ebstein s malformation experience an increase in exercise tolerance [17], decrease in cardiothoracic ratio [16], and normaliza- tion of systemic arterial oxygen saturation [17]. Late survival is generally good after tricuspid valve repair or replacement, but occasional late deaths occur, usually in the setting of persistent severe atrial (non-wolff- Parkinson-White) or ventricular arrhythmias in patients with advanced (class IV) heart failure preoperatively [8]. References Barnard CN, Schrire V. Surgical correction of Ebstein s malformation with prosthetic tricuspid valve. Surgery 1963;54: Kirklin JK, Pacific0 AD, Kirklin JW. Ebstein s anomaly. In: Grillo HC, Austen WG, Wilkins EW, Mathisen DJ, Vlahakes GJ, eds, Current therapy in cardiothoracic surgery. Toronto, Philadelphia: B.C. Decker, , Kirklin JW, Barratt-Boyes BG. Cardiac surgery. New York: Wiley, 1986:900. Watson H. Natural history of Ebstein s anomaly of the

5 Ann Thorac Surg CLASSICS KIRKLIN 151 EBSTEIN S ANOMALY tricuspid valve in childhood and adolescence: an international cooperative study of 500 cases. Br Heart J 1974;36: Carpentier A, Chauvaud S, Mace L, et al. A new reconstruction operation for Ebstein s anomaly of the tricuspid valve. J Thorac Cardiovasc Surg 1988;96: Marino JP, Mihaileanu S, Asmar BE, et al. Echocardiography and color-flow mapping evaluation of a new reconstructive surgical technique for Ebstein s anomaly. Circulation 1989; bo(supp1 1): Ports TA, Silverman NH, Schiller NB. Two-dimensional echocardiographic assessment of Ebstein s anomaly. Circulation 1978;58: Westaby S, Karp RB, Kirklin JW, Waldo AL, Blackstone EH. Surgical treatment in Ebstein s malformation. Ann Thorac Surg 1982;34:38% Bharati S, Lev M, Kirklin JW. Cardiac surgery and the conduction system. New York: Wiley, 1983:l Hunter SW, Lillehei CW. Ebstein s malformation of the tricuspid valve. Chest 1958;33: Hardy KL, May IA, Webster CA, Kimball KG. Ebstein s anomaly: a functional concept and successful definitive repair. J Thorac Cardiovasc Surg 1964;48: Danielson GK, Fuster V. Surgical repair of Ebstein s anomaly. Ann Surg 1982;196: Ng R, Somerville J, Ross D. Ebstein s anomaly: late results of surgical correction. Eur J Cardiol 1979;1: Bove EL, Kirsh MM. Valve replacement for Ebstein s anomaly of the tricuspid valve. J Thorac Cardiovasc Surg 1979;78: McKay R, Sono J, Arnold RM. Tricuspid valve replacement using an unstented pulmonary homograft. Ann Thorac Surg 1988;46:5% Mair DD, Seward JB, Driscoll DJ, Danielson GK. Surgical repair of Ebstein s anomaly: selection of patients and early and late operative results. Circulation 1985;72(Suppl 2): Driscoll DJ, Mottram CD, Danielson GK. Spectrum of exercise intolerance in 45 patients with Ebstein s anomaly and observations on exercise tolerance in 11 patients after surgical repair. J Am Coll Cardiol 1988;11: Editor s Note We asked Professor Barnard to comment on Dr Kirklin s article. Prof Barnard s Commenta y I thank you for sending me this article by Jim Kirklin. As soon as I received your letter I visited the Cardiac Clinic to find out what happened to the first patient that we treated in this manner. I was very happy to find out that he was still alive and doing very well without any medical treatment. This is now nearly.~ 28 years since the operation. It must be one of the longest implantations of a prosthetic valve in the tricuspid area. Prof C. N. Barnard