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Ebstein's malformation
Ebstein's malformation Surgical experience at the Mayo Clinic At the Mayo Clinic, 13 patients with Ebstein's malformation have undergone surgical repair since 1963. Their ages ranged from 18 months to 51 years (median 13 years). Ten patients were in Functional Class III or IV. Marked cardiomegaly, cyanosis, parado.xic emholi, and dysrhythmias secondary to Wolff-Parkinson-White syndrome were indications for operation in the remaining 3 patients. A wide range of anatomic variations was encountered. All 5 patients who underwent tricuspid annuloplastx with plication of the atrialized segment of the right ventricle survived operation. Of 5 patients who underwent prosthetic valve replacement, only one survived. Other procedures included atrial septal defect closure alone in one patient, atrial septal defect closure and relief of pulmonary stenosis in one patient, and tricuspid annuloplastx alone in one patient. One patient had concomitant mapping and division of anomalous conduction pathyways. Functional classification improved in 8 of the 10 operative survivors. There were two late sudden deaths; both patients had had preoperative dysrhythmias. The data suggest that results are improved when the atrialized segment of the right ventricle is dealt with during repair of the tricuspid valve. A combined ventricular plication and tricuspid annuloplastx yielded better early and late results than did valve replacement.
Richard C. McFaul, M.D., Zev Davis, M.D., Emilio R. Giuliani, M.D., Donald G. Ritter, M.D., and Gordon K. Danielson, M.D., Rochester, Minn.
X-rfbstein's malformation has been amendable to reparative surgery since 1962.1 The indications for surgical repair and the optimal surgical approach, however, are still controversial. All cases of Ebstein's anomaly seen at the Mayo Clinic from 1963 through 1975 were reviewed. Thirteen patients with this malformation who were surgically treated comprised the basis of this evaluation.
stenosis in 2 patients. Of the 13 patients, 12 underwent cardiac catheterization. Cardiac outputs were determined by the Fick method. All diagnoses were made before surgical intervention. Intracardiac electrode recordings were performed in 4 patients. Functional disability was assessed according to the New York Heart Association classification.
Materials and methods
Of the 13 patients in the series (Table I), 8 were females and 5 were males, and their ages ranged from 18 months to 51 years. Three patients were 2 years old or less, and 6 were between 10 and 20 years of age. One patient was in Functional Class I. This patient was asymptomatic except for two episodes of transient hemiparesis attributed to paradoxic emboli through an atrial septal defect. Two patients had only moderate functional limitations (Class II), both with moderate cyanosis. Nine patients were in Class III. One, a 2-year-old girl, had experienced several episodes of respiratory distress with a possible cardiorespiratory arrest on one occasion. This patient had a cardiothoracic ratio of 0.9 (Fig. 1). Seven patients were in congestive heart failure
Of 47 patients with Ebstein's anomaly seen from 1963 through 1975, 13 underwent surgical repair. Patients with associated pulmonary atresia, ventricular septal defects, or transposition complexes were excluded from the series. Associated conditions were atrial septal defects in 10 patients and mild pulmonary From the Mayo Clinic and Mayo Foundation, Rochester, Minn. 55901. Received for publication July 1, 1976. Accepted for publication July 23, 1976. Address for reprints: Gordon K. Danielson, M.D., c/o Section of Publications, Mayo Clinic, 200 First Street SW, Rochester, Minn. 55901.
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Volume 72 Number 6 December, 1976
and were not responding to medical management. One of these, a 21-year-old woman, had Wolff-Parkinson-White syndrome and recurrent dysrhythmias. The ninth patient, an 11-year-old boy, was showing signs of progressive deterioration in his exercise tolerance over a period of several months. One patient was in Class IV. This 51-year-old woman was in critical condition when initially seen, and repair was attempted on an emergency basis. Of the 13 patients, 6 were visibly cyanotic. Cardiac glycosides had been taken by 9 of the 13 patients. All patients had cardiomegaly with cardiothoracic ratios ranging from 0.5 to 0.9 (mean = 0.65). Electrocardiograms revealed that 8 patients had complete right bundle branch block. Six of the 13 patients had documented episodes of supraventricular dysrhythmia, with atrial fibrillation being present in the oldest patient. Five patients had a cardiac index less than 2.5 L. per minute per square meter (Table II). Three of the 10 patients with atrial septal defects had peripheral arterial saturation less than 80 per cent. A 18-month-old boy with mild pulmonary stenosis and a 2-year-old girl had severe right-to-left intracardiac shunting, with a Qp/Qs ratio of 0.3. In the group of 13 patients, mean right atrial pressures were modestly elevated, and the mean right ventricular end-diastolic pressures were normal, although values ranged from 9 to 19 mm. Hg. Surgical methods and anatomic considerations The surgical approaches varied considerably and reflect the wide range of anatomy and individual surgical preferences (Table III). Two children underwent closure of an atrial septal defect without any surgical alteration of the malformed tricuspid apparatus. One of the 2 also had moderate valvular and supravalvular pulmonary stenosis, which was corrected by pericardial enlargement of the outflow tract. Both patients had minimal displacement of the posterior and septal leaflets, and assessment at surgery confirmed only minimal valve incompetence. Five patients underwent excision of the tricuspid apparatus, with insertion of a prosthetic valve. A StarrEdwards cage ball valve was employed in 2 patients, an aortic homograft in one patient, and a porcine heterograft in 2. Atrial septal defects were closed when present (4 patients). Excision of redundant right atrial tissue was performed in one case, and a limited anterior plication of the atrialized segment was performed in another patient. Prosthetic valves were inserted near the position of the true annulus proximal to the atrialized ventricular segment and coronary sinus. A
Ebstein s malformation
91 1
Fig. 1. Severe cardiomegaly in a 2-year-old girl. Right ventricular angiogram demonstrates pronounced right atrial dilatation and tricuspid valve displacement. distinct atrialized segment was not apparent in 2 patients, although the leaflets were displaced downward and were adherent to the septal and posterior surfaces. The anterior leaflet was small and partially displaced in 2 patients, one of whom had anomalous chordae tendineae attached across the right ventricular outflow tract. Five patients underwent plication of the atrialized segment, tricuspid valve annuloplasty, and resection of redundant right atrial free wall.2 Atrial septal defects, when present (3 patients), were closed. The posterior and septal leaflets were small and displaced into the right ventricle in all 5 patients. The anterior flail-like leaflet was large in all but one patient. The anterior leaflet was fenestrated in one patient. Three patients had an atrialized segment that was described as "contracting paradoxically." One patient underwent tricuspid annuloplasty and atrial septal defect closure. Although the typical features of Ebstein's anomaly were present, the degree of displacement was less than usual. Reduction of the true tricuspid annulus decreased the tricuspid insufficiency by the creation of a monocuspid valve utilizing the large anterior leaflet. Surgical results Two patients who underwent closure of an atrial septal defect without alteration of the tricuspid valve survived the immediate postoperative period and were clinically improved. One of these (Case 13) died suddenly from a suspected dysrhythmia 7 months after the operation. This patient had had frequent episodes of
The Journal of Thoracic and Cardiovascular Surgery
9 1 2 McFaul et al.
Table I. Data in 13 cases of Ebstein s malformation Sex and Case age (yr.)
Indications for surgery
M, 19
Two transient ischemic attack episodes secondary to paradoxic emboli; otherwise functionally unlimited
F, 24
Moderate tricuspid insufficiency; low cardiac index (2.1 L./min./ sq. M.) Episodes of respiratory distress and cardiorespiratory arrest; C-T ratio 0.9 Recently progressive deterioration in tolerance
F, 2
M, 11 M, 17
Heart failure
F, 21
Heart failure; WolffParkinson-White; recurrent paroxysmal atrial tachycardia
Description of tricuspid valve
A trial septal defect*
Functional Class Preop.
Post op.
Comment
Tricuspid annuloplasty Typical anatomyt Present
Typical
Plication and annuloplasty Present
Typical
Present
Typical, except for small anterior leaflet Typical
Present Absent
Typical
Absent
Epicardial mapping
III
III
1
Poorly contracting atrialized segment
II (sudden death, 2 mo. postop.) II
Poorly contracting atrialized segment
I
Poorly contracting atrialized segment Paradoxic movement of atrialized segment; epi cardial mapping-surgi cal division accessory pathway
Legend: C-T, Cardiothoracic. * Associated condition (closed when present). tDisplacement of small or atretic septal and posterior leaflets; normal or large anterior leaflet originating from true annulus.
paroxysmal atrial tachycardia before surgery and during the immediate postoperative period. A second patient who underwent a concomitant procedure for relief of pulmonary stenosis had the tricuspid incompetence diminished clinically after surgery and was asymptomatic 12 years after the operation. Four of the 5 patients who underwent valve replacement died during the immediate postoperative period. Two were children less than 2 years of age and one was a 51-year-old critically ill woman. All 3 patients had died of low cardiac output; one of the 3 had complete atrioventricular dissociation. The fourth patient, a 13year-old girl, had a low cardiac output and died suddenly on the eleventh postoperative day, after 2 days of intermittent abdominal and chest pain. Postmortem examination revealed a thrombus within the right ventricle and throughout the heterograft valve. The only survivor was a 9-year-old child who had significant cyanosis and mild cardiomegaly preoperatively. All 5 patients who underwent plication and annuloplasty survived the immediate postoperative period.
Three patients had significant functional improvement after surgery, and one patient has remained in compensated right heart failure with moderate tricuspid incompetence one year after surgical repair. An 11-year-old child died suddenly 2 months after the operation although his over-all condition had improved before his death. An otherwise asymptomatic 19-year-old man who had experienced suspected recurrent paradoxic emboli underwent atrial septal defect closure and tricuspid annuloplasty. His recovery was complete, and he has remained asymptomatic. Discussion The wide range of pathological anatomy included in Ebstein's malformation reported by other authors3 was apparent in our 13 patients. Most of the patients had the usual displaced and hypoplastic septal and posterior leaflets and an enlarged anterolateral leaflet of the tricuspid valve. Several others, however, had less typical features with an indistinct "atrialized" ventricular
Volume 72 Number 6 December, 1976
Ebstein's malformation
91 3
Table I—Cont'd Functional
Case
5V.v uiicl age (yr.)
1
M, l'/2
Severe tricuspid insufficiency: low cardiac index (2 L./tnin./ sq. M.); mild pulmonary stenosis (27 mm. Fig. gradient)
Typical
8
F, 2
Heart failure; severe cyanosis
9
M. 9
Moderate cyanosis; recurrent paroxysmal atrial tachycardia
10
F. 13
Heart failure; C-T ratio 0.85
Typical; chordae tendineae from anterior leaflet extending into right ventricular outflow region Leaflets originate from true anomalies, but adherent to walls of right ventricular outflow region Poorly demarcated atrialized segment
II
F, 51
Profound heart failure (emergency)
12
F. 10
13
F. 13
Moderate pulmonary stenosis (50 mm. Hg); moderate tricuspid insufficiency Moderate cyanosis; recurrent paroxysmal atrial tachycardia
Indications for
surgery
Description of tricuspid valve Prosthetic
Typical
Atrial septa! defect* valve insertion Present
segment, deficiency of the anterior leaflet, or abnormal chordae tendineae attached across the right ventricular outflow region. Because of this wide anatomic variation, we agree with Bahson and associates4 that the surgical approach to patients with Ebstein's anomaly must be individualized according to the specific anatomy found at operation. Surgical experience with Ebstein's malformation was last reviewed at the Mayo Clinic in 1956.5 During the intervening period, efforts were centered on eliminating large right-to-left intracardiac shunts by closure of the atrial septal defect. The first report in-
Postop.
Comment
III
Operative death (low cardiac output)
Starr-Edwards valve; noncontracting left atrialized portion after repair
Present
III
Operative death (low cardiac output, atrioventricular dissociation)
Homograft valve; partial anterior plication
Present
III
I
Heterograft valve (Hancock)
Absent
III
Hancock heterograft valve
Present
IV
Perioperative death (11 days) Intraoperative death
Repair of associated anomalies Typical Present
Small anterior leaflet; poorly demarcated atrialized segment; chordae from anterior leaflet extending into right ventricular outflow region
Preop.
Class
Present
only II
III
Starr-Edwards valve; poorly contracting atrial segment
I
Right ventricular outflow patch
II (sudden death, 7 mo. postop.)
Atrial septal defect closure
volving surgical manipulation of the malformed tricuspid apparatus was made by Barnard and Schrire1 in 1963 after 2 patients underwent successful tricuspid valve replacement. Despite this successful beginning, controversy remains regarding the optimal surgical approach to patients wjth Ebstein's anomaly. The surgical management has basically centered around either valve replacement6 or else plication and annuloplasty of the abnormal tricuspid apparatus.7 Methods incorporating these two different approaches also have been proposed.8 In our experience, plication of the "atrialized"
The Journal of Thoracic and Cardiovascular Surgery
9 1 4 McFaul et al.
Table II. Catheterization data in 12 patients with Ebstein s malformation
Table III. Surgical procedures and results in 13 cases of Ebstein's malformation No. of patients
No. of patients
Died
Cardiac index (L./min./sq. M.) <2.0 2.0-2.4 2.5-2.9 >3.0 Arterial saturation (%) <80 81-90 >90
Right atrial pressure (mm. Hg) a wave v wave RVEDP
Procedures
Mean
Range
10 12 9
6-13 4-21 6-19
Legend: RVEDP. Right ventricular end-diastolic pressure.
ventricular segment combined with tricuspid annuloplasty provides the greatest inprovement in symptoms with the lowest morbidity and mortality rate. Our data are compatible with Hardy and associates'7 concept that the thin-wall atrialized ventricular segment creates a significant hemodynamic disturbance which must be dealt with at corrective repair. The right ventricular dysfunction caused by this poor and often paradoxically contracting segment may be analogous to the hemodynamic disturbance created by dyskinetic segments within the left ventricle as seen after myocardial infarction. However, all but one of our patients who underwent repair by plication and annuloplasty had a well-defined atrialized segment and an enlarged anterior leaflet. The one patient who had a small anterior leaflet had moderate tricuspid incompetence after surgical repair and required inotropic drugs during the immediate postoperative period in order to maintain adequate cardiac output. Replacement of the malformed tricuspid valve, with one exception, has been unsuccessful in our experience. The reasons for this are not completely apparent, although the results are consistent with the high surgical mortality rate cited in the studies by Watson.9 Three of our 5 patients had distinct atrialized segments that were not eliminated in the reparative operation. Persistence of this abnormal feature may have contributed to the low cardiac output seen in these patients before death. Two of the 5 patients, however, had anatomy that presumably precluded the plication method and necessitated valve replacement: One had abnormal
Tricuspid annuloplasty Plication and annuloplasty Valve replacement Starr-Edwards Homograft Heterograt't Repair of associated anomalies Relief of pulmonary stenosis with outflow tract patch Closure of atrial septal defect
Total
2 1 2
Survived
Early*
Late
1
1
0
0
5
4
0
1 (2 mo.t)
5
2
0 0 1
1
1
2 1 1
4
0
0 0 0
0
1
1
1
0
0
1
0
0
1 (7 mo.t)
*Less than 30 days after operation. tRecurrent arrhythmias before operation.
chordae tendineae from the anterior leaflet across the right ventricular outflow tract, and the other had an anterior leaflet that was too deficient to function adequately as a monocuspid valve. The indications for surgical intervention in Ebstein's anomaly have not been clearly defined. A recent study9 clarifies certain aspects. Patients in Functional Classes I and II should be medically managed,9 as was done for most of our patients with Ebstein's malformation who were seen during the period of study. Exceptions that would prompt earlier surgical intervention, as they did in our series, are moderate-to-severe cyanosis, paradoxic emboli, and right ventricular outflow obstruction. Cyanotic patients with large atrial septal defects and only minor functional abnormalities of the tricuspid valve may benefit from closure of the atrial septal defect alone, without modification of the tricuspid apparatus, as in our Case 13. The extent to which increased afterload on the right ventricle contributes to a patient's symptoms is difficult to ascertain, both clinically and in the laboratory. However, surgical relief of pulmonary stenosis, when present, may be sufficient to reduce the tricuspid insufficiency to more tolerable levels, but concomitant tricuspid annuloplasty would seem to be preferable. Patients in Classes III and IV should be considered surgical candidates. The extent to which gross cardiomegaly influences
Volume 72 Number 6 December, 1976
the decision for surgical repair is uncertain. Kumar and associates 10 found that only 35 per cent of patients with severe cardiomegaly survived beyond 8 years after diagnosis, in contrast to Watson, 9 who found a lower correlation between cardiac size and progression of disability. Laboratory data from our small series of patients suggest that the correlation between cardiac function and cardiac size may be low, as illustrated by the 2-year-old child with a cardiothoracic ratio of 0.9 and a cardiac index of 4 L. per minute per square meter and a 13-year-old child with a cardiothoracic ratio of 0.5 and a cardiac index of 2 L. per minute per square meter. Nevertheless, large cardiac size has been associated with increased operative risk and poor long-term results in patients with aortic" and mitral 12 valve disease, and cardiomegaly also may influence adversely the surgical results in Ebstein's anomaly. Thus progressive increase in heart size is a relative indication for operation. Atrial dysrhythmias are common in patients with Ebstein's malformation and often present therapeutic problems. 9 - 10 Refractoriness to the usual antiarrhythmic agents was noted in some of our patients before operation. The sudden late death of 2 of the 7 patients who survived the immediate postoperative period is consistent with the observation 10 that surgery may not reduce the episodes of recurrent dysrhythmias nor the incidence of sudden death. This experience suggests that operation should not be undertaken just because poorly controlled atrial dysrhythmias exist, unless the over-all functional status warrants surgical intervention. An exception is the patient with Ebstein's anomaly and Wolff-Parkinson-White syndrome who has refractory and life-threatening atrial dysrhythmias. Because intraoperative epicardial and endocardial mapping and surgical division of the accessory pathway are possible, especially with type B Wolff-ParkinsonWhite syndrome, which is the type usually associated with Ebstein's anomaly, these patients should benefit from surgical intervention. We now perform preliminary electrophysiological studies on all patients with Ebstein's anomaly who have a history of supraventricular tachycardia. Addendum Three additional patients have undergone repair of Ebstein's malformation by the technique of plication, tricuspid
Ebstein's malformation
9 15
annuloplasty, and resection of redundant right atrial free wall. One patient also underwent electrical mapping and successful division of an accessory conduction pathway (WolffParkinson-White type B). All 3 survived operation and are improved.
REFERENCES 1 Barnard, C. N., and Schrire, V.: Surgical Correction of Ebstein's Malformation With Prosthetic Tricuspid Valve, Surgery 54: 302, 1963. 2 Danielson, G. K.: Unpublished data. 3 Lev, M., Liberthson, R. R., Joseph, R. H., Seten, C. E., Kunske, R. D., Eckner, F. A. O., and Miller, R. A.: The Pathologic Anatomy of Ebstein's Disease, Arch. Pathol. 90: 334, 1970. 4 Bahnson, H. T., Bauersfeld, S. R., and Smith, J. W.: Pathological Anatomy and Surgical Correction of Ebstein's Anomaly, Circulation 31: 3, 1965 (Suppl. 1). 5 Kilby, R. A., DuShane, J. W., Wood, E. H., and Burchell, H. B.: Ebstein's Malformation: A Clinical and Laboratory Study, Medicine (Baltimore) 35: 161, 1956. 6 Lillehei, C. W., Kalke, B. R., and Carlson, R. G.: Evolution of Corrective Surgery for Ebstein's Anomaly, Circulation 35: 111, 1967 (Suppl. 1). 7 Hardy, K. L., May, 1. A., Webster, C. A., and Kimball K. G.: Ebstein's Anomaly: A Functional Concept and Successful Definitive Repair, J. THORAC. CARDIOVASC. SURG. 48: 927,
1964.
8 Timmis, H. H., Hardy, J. D., and Watson, D. G.: The Surgical Management of Ebstein's Anomaly: The Combined Use of Tricuspid Valve Replacement, Atrioventricular Plication, and Atrioplasty, J. THORAC. CARDIOVASC. SURG. 53: 385,
1967.
9 Watson, H.: Natural History of Ebstein's Anomaly of Tricuspid Valve in Childhood and Adolescence: An International Co-operative Study of 505 Cases, Br. Heart J. 36: 417, 1974. 10 Kumar, A. E., Fyler, D. C , Miettinen, O. S., and Nadas, A. S.: Ebstein's Anomaly: Clinical Profile and Natural History, Am. J. Cardiol. 28: 84, 1971. 11 Braun, L. O., Kincaid, O. W., and McGoon, D. C : Prognosis of Aortic Valve Replacement in Relation to the Preoperative Heart Size, J. THORAC. CARDIOVASC. SURG.
65: 381, 1973. 12 Barnhorst, D. A., Oxman, H. A., Connolly, D. C , Pluth, J. R., Danielson, G. K., Wallace, R. B., and McGoon, D. C : Long-Term Follow-up of Isolated Replacement of the Aortic or Mitral Valve With the StarrEdwards Prosthesis, Am. J. Cardiol. 35:228, 1975.
Richard C. McFaul, M.D., Zev Davis, M.D., Emilio R. Giuliani, M.D., Donald G. Ritter, M.D., and Gordon K. Danielson, M.D., Rochester, Minn.
X-rfbstein's malformation has been amendable to reparative surgery since 1962.1 The indications for surgical repair and the optimal surgical approach, however, are still controversial. All cases of Ebstein's anomaly seen at the Mayo Clinic from 1963 through 1975 were reviewed. Thirteen patients with this malformation who were surgically treated comprised the basis of this evaluation.
stenosis in 2 patients. Of the 13 patients, 12 underwent cardiac catheterization. Cardiac outputs were determined by the Fick method. All diagnoses were made before surgical intervention. Intracardiac electrode recordings were performed in 4 patients. Functional disability was assessed according to the New York Heart Association classification.
Materials and methods
Of the 13 patients in the series (Table I), 8 were females and 5 were males, and their ages ranged from 18 months to 51 years. Three patients were 2 years old or less, and 6 were between 10 and 20 years of age. One patient was in Functional Class I. This patient was asymptomatic except for two episodes of transient hemiparesis attributed to paradoxic emboli through an atrial septal defect. Two patients had only moderate functional limitations (Class II), both with moderate cyanosis. Nine patients were in Class III. One, a 2-year-old girl, had experienced several episodes of respiratory distress with a possible cardiorespiratory arrest on one occasion. This patient had a cardiothoracic ratio of 0.9 (Fig. 1). Seven patients were in congestive heart failure
Of 47 patients with Ebstein's anomaly seen from 1963 through 1975, 13 underwent surgical repair. Patients with associated pulmonary atresia, ventricular septal defects, or transposition complexes were excluded from the series. Associated conditions were atrial septal defects in 10 patients and mild pulmonary From the Mayo Clinic and Mayo Foundation, Rochester, Minn. 55901. Received for publication July 1, 1976. Accepted for publication July 23, 1976. Address for reprints: Gordon K. Danielson, M.D., c/o Section of Publications, Mayo Clinic, 200 First Street SW, Rochester, Minn. 55901.
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Clinical and laboratory appraisal
Volume 72 Number 6 December, 1976
and were not responding to medical management. One of these, a 21-year-old woman, had Wolff-Parkinson-White syndrome and recurrent dysrhythmias. The ninth patient, an 11-year-old boy, was showing signs of progressive deterioration in his exercise tolerance over a period of several months. One patient was in Class IV. This 51-year-old woman was in critical condition when initially seen, and repair was attempted on an emergency basis. Of the 13 patients, 6 were visibly cyanotic. Cardiac glycosides had been taken by 9 of the 13 patients. All patients had cardiomegaly with cardiothoracic ratios ranging from 0.5 to 0.9 (mean = 0.65). Electrocardiograms revealed that 8 patients had complete right bundle branch block. Six of the 13 patients had documented episodes of supraventricular dysrhythmia, with atrial fibrillation being present in the oldest patient. Five patients had a cardiac index less than 2.5 L. per minute per square meter (Table II). Three of the 10 patients with atrial septal defects had peripheral arterial saturation less than 80 per cent. A 18-month-old boy with mild pulmonary stenosis and a 2-year-old girl had severe right-to-left intracardiac shunting, with a Qp/Qs ratio of 0.3. In the group of 13 patients, mean right atrial pressures were modestly elevated, and the mean right ventricular end-diastolic pressures were normal, although values ranged from 9 to 19 mm. Hg. Surgical methods and anatomic considerations The surgical approaches varied considerably and reflect the wide range of anatomy and individual surgical preferences (Table III). Two children underwent closure of an atrial septal defect without any surgical alteration of the malformed tricuspid apparatus. One of the 2 also had moderate valvular and supravalvular pulmonary stenosis, which was corrected by pericardial enlargement of the outflow tract. Both patients had minimal displacement of the posterior and septal leaflets, and assessment at surgery confirmed only minimal valve incompetence. Five patients underwent excision of the tricuspid apparatus, with insertion of a prosthetic valve. A StarrEdwards cage ball valve was employed in 2 patients, an aortic homograft in one patient, and a porcine heterograft in 2. Atrial septal defects were closed when present (4 patients). Excision of redundant right atrial tissue was performed in one case, and a limited anterior plication of the atrialized segment was performed in another patient. Prosthetic valves were inserted near the position of the true annulus proximal to the atrialized ventricular segment and coronary sinus. A
Ebstein s malformation
91 1
Fig. 1. Severe cardiomegaly in a 2-year-old girl. Right ventricular angiogram demonstrates pronounced right atrial dilatation and tricuspid valve displacement. distinct atrialized segment was not apparent in 2 patients, although the leaflets were displaced downward and were adherent to the septal and posterior surfaces. The anterior leaflet was small and partially displaced in 2 patients, one of whom had anomalous chordae tendineae attached across the right ventricular outflow tract. Five patients underwent plication of the atrialized segment, tricuspid valve annuloplasty, and resection of redundant right atrial free wall.2 Atrial septal defects, when present (3 patients), were closed. The posterior and septal leaflets were small and displaced into the right ventricle in all 5 patients. The anterior flail-like leaflet was large in all but one patient. The anterior leaflet was fenestrated in one patient. Three patients had an atrialized segment that was described as "contracting paradoxically." One patient underwent tricuspid annuloplasty and atrial septal defect closure. Although the typical features of Ebstein's anomaly were present, the degree of displacement was less than usual. Reduction of the true tricuspid annulus decreased the tricuspid insufficiency by the creation of a monocuspid valve utilizing the large anterior leaflet. Surgical results Two patients who underwent closure of an atrial septal defect without alteration of the tricuspid valve survived the immediate postoperative period and were clinically improved. One of these (Case 13) died suddenly from a suspected dysrhythmia 7 months after the operation. This patient had had frequent episodes of
The Journal of Thoracic and Cardiovascular Surgery
9 1 2 McFaul et al.
Table I. Data in 13 cases of Ebstein s malformation Sex and Case age (yr.)
Indications for surgery
M, 19
Two transient ischemic attack episodes secondary to paradoxic emboli; otherwise functionally unlimited
F, 24
Moderate tricuspid insufficiency; low cardiac index (2.1 L./min./ sq. M.) Episodes of respiratory distress and cardiorespiratory arrest; C-T ratio 0.9 Recently progressive deterioration in tolerance
F, 2
M, 11 M, 17
Heart failure
F, 21
Heart failure; WolffParkinson-White; recurrent paroxysmal atrial tachycardia
Description of tricuspid valve
A trial septal defect*
Functional Class Preop.
Post op.
Comment
Tricuspid annuloplasty Typical anatomyt Present
Typical
Plication and annuloplasty Present
Typical
Present
Typical, except for small anterior leaflet Typical
Present Absent
Typical
Absent
Epicardial mapping
III
III
1
Poorly contracting atrialized segment
II (sudden death, 2 mo. postop.) II
Poorly contracting atrialized segment
I
Poorly contracting atrialized segment Paradoxic movement of atrialized segment; epi cardial mapping-surgi cal division accessory pathway
Legend: C-T, Cardiothoracic. * Associated condition (closed when present). tDisplacement of small or atretic septal and posterior leaflets; normal or large anterior leaflet originating from true annulus.
paroxysmal atrial tachycardia before surgery and during the immediate postoperative period. A second patient who underwent a concomitant procedure for relief of pulmonary stenosis had the tricuspid incompetence diminished clinically after surgery and was asymptomatic 12 years after the operation. Four of the 5 patients who underwent valve replacement died during the immediate postoperative period. Two were children less than 2 years of age and one was a 51-year-old critically ill woman. All 3 patients had died of low cardiac output; one of the 3 had complete atrioventricular dissociation. The fourth patient, a 13year-old girl, had a low cardiac output and died suddenly on the eleventh postoperative day, after 2 days of intermittent abdominal and chest pain. Postmortem examination revealed a thrombus within the right ventricle and throughout the heterograft valve. The only survivor was a 9-year-old child who had significant cyanosis and mild cardiomegaly preoperatively. All 5 patients who underwent plication and annuloplasty survived the immediate postoperative period.
Three patients had significant functional improvement after surgery, and one patient has remained in compensated right heart failure with moderate tricuspid incompetence one year after surgical repair. An 11-year-old child died suddenly 2 months after the operation although his over-all condition had improved before his death. An otherwise asymptomatic 19-year-old man who had experienced suspected recurrent paradoxic emboli underwent atrial septal defect closure and tricuspid annuloplasty. His recovery was complete, and he has remained asymptomatic. Discussion The wide range of pathological anatomy included in Ebstein's malformation reported by other authors3 was apparent in our 13 patients. Most of the patients had the usual displaced and hypoplastic septal and posterior leaflets and an enlarged anterolateral leaflet of the tricuspid valve. Several others, however, had less typical features with an indistinct "atrialized" ventricular
Volume 72 Number 6 December, 1976
Ebstein's malformation
91 3
Table I—Cont'd Functional
Case
5V.v uiicl age (yr.)
1
M, l'/2
Severe tricuspid insufficiency: low cardiac index (2 L./tnin./ sq. M.); mild pulmonary stenosis (27 mm. Fig. gradient)
Typical
8
F, 2
Heart failure; severe cyanosis
9
M. 9
Moderate cyanosis; recurrent paroxysmal atrial tachycardia
10
F. 13
Heart failure; C-T ratio 0.85
Typical; chordae tendineae from anterior leaflet extending into right ventricular outflow region Leaflets originate from true anomalies, but adherent to walls of right ventricular outflow region Poorly demarcated atrialized segment
II
F, 51
Profound heart failure (emergency)
12
F. 10
13
F. 13
Moderate pulmonary stenosis (50 mm. Hg); moderate tricuspid insufficiency Moderate cyanosis; recurrent paroxysmal atrial tachycardia
Indications for
surgery
Description of tricuspid valve Prosthetic
Typical
Atrial septa! defect* valve insertion Present
segment, deficiency of the anterior leaflet, or abnormal chordae tendineae attached across the right ventricular outflow region. Because of this wide anatomic variation, we agree with Bahson and associates4 that the surgical approach to patients with Ebstein's anomaly must be individualized according to the specific anatomy found at operation. Surgical experience with Ebstein's malformation was last reviewed at the Mayo Clinic in 1956.5 During the intervening period, efforts were centered on eliminating large right-to-left intracardiac shunts by closure of the atrial septal defect. The first report in-
Postop.
Comment
III
Operative death (low cardiac output)
Starr-Edwards valve; noncontracting left atrialized portion after repair
Present
III
Operative death (low cardiac output, atrioventricular dissociation)
Homograft valve; partial anterior plication
Present
III
I
Heterograft valve (Hancock)
Absent
III
Hancock heterograft valve
Present
IV
Perioperative death (11 days) Intraoperative death
Repair of associated anomalies Typical Present
Small anterior leaflet; poorly demarcated atrialized segment; chordae from anterior leaflet extending into right ventricular outflow region
Preop.
Class
Present
only II
III
Starr-Edwards valve; poorly contracting atrial segment
I
Right ventricular outflow patch
II (sudden death, 7 mo. postop.)
Atrial septal defect closure
volving surgical manipulation of the malformed tricuspid apparatus was made by Barnard and Schrire1 in 1963 after 2 patients underwent successful tricuspid valve replacement. Despite this successful beginning, controversy remains regarding the optimal surgical approach to patients wjth Ebstein's anomaly. The surgical management has basically centered around either valve replacement6 or else plication and annuloplasty of the abnormal tricuspid apparatus.7 Methods incorporating these two different approaches also have been proposed.8 In our experience, plication of the "atrialized"
The Journal of Thoracic and Cardiovascular Surgery
9 1 4 McFaul et al.
Table II. Catheterization data in 12 patients with Ebstein s malformation
Table III. Surgical procedures and results in 13 cases of Ebstein's malformation No. of patients
No. of patients
Died
Cardiac index (L./min./sq. M.) <2.0 2.0-2.4 2.5-2.9 >3.0 Arterial saturation (%) <80 81-90 >90
Right atrial pressure (mm. Hg) a wave v wave RVEDP
Procedures
Mean
Range
10 12 9
6-13 4-21 6-19
Legend: RVEDP. Right ventricular end-diastolic pressure.
ventricular segment combined with tricuspid annuloplasty provides the greatest inprovement in symptoms with the lowest morbidity and mortality rate. Our data are compatible with Hardy and associates'7 concept that the thin-wall atrialized ventricular segment creates a significant hemodynamic disturbance which must be dealt with at corrective repair. The right ventricular dysfunction caused by this poor and often paradoxically contracting segment may be analogous to the hemodynamic disturbance created by dyskinetic segments within the left ventricle as seen after myocardial infarction. However, all but one of our patients who underwent repair by plication and annuloplasty had a well-defined atrialized segment and an enlarged anterior leaflet. The one patient who had a small anterior leaflet had moderate tricuspid incompetence after surgical repair and required inotropic drugs during the immediate postoperative period in order to maintain adequate cardiac output. Replacement of the malformed tricuspid valve, with one exception, has been unsuccessful in our experience. The reasons for this are not completely apparent, although the results are consistent with the high surgical mortality rate cited in the studies by Watson.9 Three of our 5 patients had distinct atrialized segments that were not eliminated in the reparative operation. Persistence of this abnormal feature may have contributed to the low cardiac output seen in these patients before death. Two of the 5 patients, however, had anatomy that presumably precluded the plication method and necessitated valve replacement: One had abnormal
Tricuspid annuloplasty Plication and annuloplasty Valve replacement Starr-Edwards Homograft Heterograt't Repair of associated anomalies Relief of pulmonary stenosis with outflow tract patch Closure of atrial septal defect
Total
2 1 2
Survived
Early*
Late
1
1
0
0
5
4
0
1 (2 mo.t)
5
2
0 0 1
1
1
2 1 1
4
0
0 0 0
0
1
1
1
0
0
1
0
0
1 (7 mo.t)
*Less than 30 days after operation. tRecurrent arrhythmias before operation.
chordae tendineae from the anterior leaflet across the right ventricular outflow tract, and the other had an anterior leaflet that was too deficient to function adequately as a monocuspid valve. The indications for surgical intervention in Ebstein's anomaly have not been clearly defined. A recent study9 clarifies certain aspects. Patients in Functional Classes I and II should be medically managed,9 as was done for most of our patients with Ebstein's malformation who were seen during the period of study. Exceptions that would prompt earlier surgical intervention, as they did in our series, are moderate-to-severe cyanosis, paradoxic emboli, and right ventricular outflow obstruction. Cyanotic patients with large atrial septal defects and only minor functional abnormalities of the tricuspid valve may benefit from closure of the atrial septal defect alone, without modification of the tricuspid apparatus, as in our Case 13. The extent to which increased afterload on the right ventricle contributes to a patient's symptoms is difficult to ascertain, both clinically and in the laboratory. However, surgical relief of pulmonary stenosis, when present, may be sufficient to reduce the tricuspid insufficiency to more tolerable levels, but concomitant tricuspid annuloplasty would seem to be preferable. Patients in Classes III and IV should be considered surgical candidates. The extent to which gross cardiomegaly influences
Volume 72 Number 6 December, 1976
the decision for surgical repair is uncertain. Kumar and associates 10 found that only 35 per cent of patients with severe cardiomegaly survived beyond 8 years after diagnosis, in contrast to Watson, 9 who found a lower correlation between cardiac size and progression of disability. Laboratory data from our small series of patients suggest that the correlation between cardiac function and cardiac size may be low, as illustrated by the 2-year-old child with a cardiothoracic ratio of 0.9 and a cardiac index of 4 L. per minute per square meter and a 13-year-old child with a cardiothoracic ratio of 0.5 and a cardiac index of 2 L. per minute per square meter. Nevertheless, large cardiac size has been associated with increased operative risk and poor long-term results in patients with aortic" and mitral 12 valve disease, and cardiomegaly also may influence adversely the surgical results in Ebstein's anomaly. Thus progressive increase in heart size is a relative indication for operation. Atrial dysrhythmias are common in patients with Ebstein's malformation and often present therapeutic problems. 9 - 10 Refractoriness to the usual antiarrhythmic agents was noted in some of our patients before operation. The sudden late death of 2 of the 7 patients who survived the immediate postoperative period is consistent with the observation 10 that surgery may not reduce the episodes of recurrent dysrhythmias nor the incidence of sudden death. This experience suggests that operation should not be undertaken just because poorly controlled atrial dysrhythmias exist, unless the over-all functional status warrants surgical intervention. An exception is the patient with Ebstein's anomaly and Wolff-Parkinson-White syndrome who has refractory and life-threatening atrial dysrhythmias. Because intraoperative epicardial and endocardial mapping and surgical division of the accessory pathway are possible, especially with type B Wolff-ParkinsonWhite syndrome, which is the type usually associated with Ebstein's anomaly, these patients should benefit from surgical intervention. We now perform preliminary electrophysiological studies on all patients with Ebstein's anomaly who have a history of supraventricular tachycardia. Addendum Three additional patients have undergone repair of Ebstein's malformation by the technique of plication, tricuspid
Ebstein's malformation
9 15
annuloplasty, and resection of redundant right atrial free wall. One patient also underwent electrical mapping and successful division of an accessory conduction pathway (WolffParkinson-White type B). All 3 survived operation and are improved.
REFERENCES 1 Barnard, C. N., and Schrire, V.: Surgical Correction of Ebstein's Malformation With Prosthetic Tricuspid Valve, Surgery 54: 302, 1963. 2 Danielson, G. K.: Unpublished data. 3 Lev, M., Liberthson, R. R., Joseph, R. H., Seten, C. E., Kunske, R. D., Eckner, F. A. O., and Miller, R. A.: The Pathologic Anatomy of Ebstein's Disease, Arch. Pathol. 90: 334, 1970. 4 Bahnson, H. T., Bauersfeld, S. R., and Smith, J. W.: Pathological Anatomy and Surgical Correction of Ebstein's Anomaly, Circulation 31: 3, 1965 (Suppl. 1). 5 Kilby, R. A., DuShane, J. W., Wood, E. H., and Burchell, H. B.: Ebstein's Malformation: A Clinical and Laboratory Study, Medicine (Baltimore) 35: 161, 1956. 6 Lillehei, C. W., Kalke, B. R., and Carlson, R. G.: Evolution of Corrective Surgery for Ebstein's Anomaly, Circulation 35: 111, 1967 (Suppl. 1). 7 Hardy, K. L., May, 1. A., Webster, C. A., and Kimball K. G.: Ebstein's Anomaly: A Functional Concept and Successful Definitive Repair, J. THORAC. CARDIOVASC. SURG. 48: 927,
1964.
8 Timmis, H. H., Hardy, J. D., and Watson, D. G.: The Surgical Management of Ebstein's Anomaly: The Combined Use of Tricuspid Valve Replacement, Atrioventricular Plication, and Atrioplasty, J. THORAC. CARDIOVASC. SURG. 53: 385,
1967.
9 Watson, H.: Natural History of Ebstein's Anomaly of Tricuspid Valve in Childhood and Adolescence: An International Co-operative Study of 505 Cases, Br. Heart J. 36: 417, 1974. 10 Kumar, A. E., Fyler, D. C , Miettinen, O. S., and Nadas, A. S.: Ebstein's Anomaly: Clinical Profile and Natural History, Am. J. Cardiol. 28: 84, 1971. 11 Braun, L. O., Kincaid, O. W., and McGoon, D. C : Prognosis of Aortic Valve Replacement in Relation to the Preoperative Heart Size, J. THORAC. CARDIOVASC. SURG.
65: 381, 1973. 12 Barnhorst, D. A., Oxman, H. A., Connolly, D. C , Pluth, J. R., Danielson, G. K., Wallace, R. B., and McGoon, D. C : Long-Term Follow-up of Isolated Replacement of the Aortic or Mitral Valve With the StarrEdwards Prosthesis, Am. J. Cardiol. 35:228, 1975.