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Atrioventricular Valve Repair or Replacement in Atriopulmonary Anastomosis Surgical Considerations. Florentino J. Vargas et al.

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Atrioventricular Valve Repair or Replacement
in Atriopulmonary Anastomosis: Surgical Considerations
Florentino J. Vargas, M.D., John E. Mayer, Jr., M.D., Richard A. Jonas, M.D.,
and Aldo R. Castaneda, M.D.
ABSTRACT Three patients who underwent a modified
Fontan-Kreutzer (F-K) operation required additional procedures to correct left atrioventricular valve regurgitation.
Valve replacement was performed in two additional procedures, and initial annuloplasty with a Carpentier ring was
carried out in the third. All 3 survived the combined procedures and are doing well after a follow-up period ranging
from five months to three years. More frequent presentation of these types of patients can be expected with
broadening indications for F-K procedure to more complex
lesions.
Elevated pulmonary venous pressures can produce disastrous results after an atriopulmonary connection procedure (Fontan-Kreutzer, or F-K), and normal left atrioventricular valve (LAVV) function has been considered a
prerequisite to this procedure [l].As the F-K approach
has been applied to a number of more complex anatomic
defects [2-41, which may include atrioventricular (AV)
valve abnormalities, the problem of regurgitant AV
valves in patients who otherwise would be good candidates for an F-K type of repair has become apparent. The
purpose of this report is to describe the diagnostic and
surgical features of 3 patients in whom LAVV repair or
replacement was subsequently or simultaneously undertaken in conjunction with an F-K procedure.
Case Reports
Patient 2
S.M., an 18-year-old man, had a single ventricle, Ltransposition of the great arteries (S,L,L), pulmonary
stenosis, and probable regurgitation of both L A W and
right atrioventricular valve (RAVV). Several cardiac
catheterization studies had failed to quantitate the degree of insufficiency of each atrioventricular valve
( A W ) . On this admission the patient was cyanotic and
moderately incapacitated (New York Heart Association
[NYHA] Functional Class 11). Chest roentgenogram
showed moderate cardiac enlargement with reduced
pulmonary artery markings. A harsh holosystolic murmur was heard over the pericardium. Cardiac catheteriFrom the Department of Cardiovascular Surgery, The Children’s Hospital, and the Department of Surgery, Harvard Medical School, Boston,
MA.
Accepted for publication June 27, 1986.
Address reprint requests to h.Castaneda, Department of Cardiovascular Surgery, The Children’s Hospital, 300 Longwood Ave, Boston,
MA 02115.
403 Ann Thorac Surg 43:403-405, Apr 1987
zation and two-dimensional echocardiography confirmed the anatomic diagnosis and also identified severe
RAW and mild L A W regurgitation. At catheterization, left atrial pressure was 14 mm Hg, left ventricular
end-diastolic pressure (VEDP) was 12 mm Hg, mean
pulmonary artery pressure was 15 mm Hg, and calculated pulmonary arteriolar vascular resistance (indexed) was 2 Wood units/m2. operative repair included
patch obliteration of a hypoplastic, regurgitant RAW,
patch closure of an atrial septal defect, suture closure of
the pulmonary valve, and direct atriopulmonary anastomosis between the cavoatrial junction and the right pulmonary artery. Because of inability to wean the patient
from bypass, and the presence of a mean left atrial pressure of 20 mm Hg with prominent V waves, severe residual L A W regurgitation was diagnosed. Through a
left atriotomy a prolapsed Ebstein-like deformed LAVV
was resected and replaced with a no. 27 St. Jude Medical
prosthesis. A residual leak in the atrial baffle suture line
resulted in postoperative cyanosis and was repaired 1
day later. Because of persistent recurrent pericardial effusions, a pericardial-pleural window was created 30
days later. He was discharged 45 days after admission in
good condition. A repeat catheterization and echocardiogram prior to discharge showed good ventricular
function and absence of gradients across the AV valve
prosthesis or across the atriopulmonary anastomosis.
Normal function of the prothesis was demonstrated
from the left ventriculogram (Figure). Two years later
this patient is clinically well (NYHA Functional Class I)
on diuretics and anticoagulants.
Patient 2
C.L., an 8-year-old boy who had previously undergone
a Blalock-Taussig shunt procedure, was admitted with
tricuspid atresia, normally related great arteries, and
pulmonary stenosis as diagnosed by catheterization and
echocardiography. The calculated pulmonary vascular
resistance (indexed) was 0.2 Wood units/m2. Pulmonary
pressure was 20 mm Hg (mean) and VEDP was 7 mm
Hg.The Blalock-Taussig shunt appeared to be large angiographically. Although a murmur of mitral regurgitation was present, the degree of valve insufficiency was
considered mild and was thought to have been accentuated by LAVV distortion by the angiography catheter.
Repair included shunt ligation, suture closure of the pulmonary valve and atrial septal defect, and direct right
atrial appendage-to-right pulmonary artery anastomosis, which was augmented with an autologous pericardial patch. After an uncomplicated postoperative
404
The Annals of Thoracic Surgery Vol 43 No 4 April 1987
Postoperative study after Fontan-Kreutzer procedure with LAVV replacement (Patient 2 ) : ( A ) Right atrial injecton shows simultaneous
filling of both right atrium (RA) and pulmonary artery (PA) which
have been connected with an atriopulmonary anastomosis. There is no
evidence of restriction at the anastomotic orifice. The LAVV has been
replaced with a no. 29 St. 1ude prosthesis (arrow). (B) Ventriculogram displayed good ventricular contraction and normal prosthetic
function (arrow). Both prosthetic regurgitation and peri-prosthetic
leaks are absent. (SV = single ventricle).
course, the patient was discharged in good condition, on
diuretics and digoxin.
Although asymptomatic, a murmur suggestive of mitral regurgitation was still present at the time of discharge. The murmur gradually became more intense,
cardiomegaly increased, and cardiac failure developed.
Cardiac catheterization and echocardiography disclosed
severe mitral valve regurgitation. Reoperation was undertaken two years after the initial procedure, and a prolapsed mitral valve (with elongated chordae of both
leaflets) was replaced with a no. 29 St. Jude Medical
prosthesis. The patient was weaned from bypass uneventfully. A right atrial pressure of 12 mm Hg and a left
atrial pressure of 7 mm Hg were recorded two days postoperatively. The patient was discharged on diuretics and
anticoagulants and has remained asymptomatic (NYHA
Functional Class I) for three years after the reoperation.
Patient 3
J.M., a 10-year-old boy, was admitted with the diagnosis
of tricuspid atresia, D-transposition of the great vessels,
severe pulmonary stenosis, and moderate mitral regurgitation, confirmed by both catheterization and twodimensional echocardiographic evaluation. Although
VEDP was 7 mm Hg, a mild degree of left ventricular
dysfunction was suggested by the echocardiogram
(shortening fraction = 27%;ejection fraction = 52%).At
operation, the mitral valve regurgitation was considered
significant as assessed by passively filling the left ventri-
cle with saline (after excision of the atrial septum). The
regurgitation seemed to result primarily from a massively dilated annulus. Both the leaflet tissue and its
subvalvular apparatus seemed normal. A mitral annuloplasty with a no. 34 Carpentier ring was performed. Retesting of valve function showed considerable improvement. The atrial septa1 defect and the pulmonary valve
annulus was closed, and a direct right atriopulmonary
anastomosis was performed. The patient’s postoperative
course was uneventful. Left atrial pressure was below 5
mm Hg, and the right atrial pressure was 13 mm Hg. He
was discharged in good hemodynamic condition and
has remained well for five months since the operation.
Comment
Normal AV valve function has been considered to be an
indispensable requirement for an F-K procedure [l, 21.
To our knowledge there are no reports in the medical
literature of patients who had AV valve replacement or
repair as an adjunct to a F-K operation. Because the indications for F-K procedure now include a more complex
spectrum of lesions (3, 41, the need for AV valve repair
or replacement has become apparent in some patients.
These 3 patients illustrate the diagnostic and intraoperative management problems that can arise in this setting.
Mitral regurgitation with tricuspid atresia was recognized clinically and was associated with pathologic abnormalities of the mitral valve in an unpublished necropsy series (S. Van Praagh, personal correspondence,
May, 1981).Abnormal right or left AV valves have been
also reported either in D- or L-loop types of single ventricle [ 5 ] .The need for AV valve repair may be more likely
to occur in those patients with abnormal leaflet anatomy
(common AVV) or in those in whom a morphologic
tricuspid valve has to be used as the sole systemic A W
for a F-K procedure (such as in certain L-loop single ventricles or in mitral atresia and hypoplastic left ventricular
syndrome). In the latter cases, there is both anatomic
and clinical evidence of frequent tricuspid valve abnor-
405 Vargas, Mayer, Jonas, Castaneda: Atrioventricular Valve Repair or Replacement
malities and dysfunction. Bharati and Lev [6] reported a
high incidence of abnormal tricuspid valve in a necropsy
series of hearts with hypoplastic left ventricular syndrome. Tricuspid valve abnormalities causing significant
AV valve insufficiency occurred in 2 patients with hypoplastic left ventricular syndrome who subsequently required prosthetic valve replacement after an otherwise
successful first-stage palliation for the syndrome [7].
In the presence of L A W regurgitation, hemodynamic
evaluation of patients for a F-K operation can be difficult. First, the presence of a mean pulmonary artery
pressure of 20 mm Hg or higher in these patients must
be considered in a different light from that occurring in
patients with normal AVV function, because the pulmonary artery pressure may be expected to fall after normal
AVV function has been restored by AVV repair or replacement. Similar considerations apply to the evaluation of VEDP. In these cases, the additional ventricular volume overload produced by AVV incompetence
makes the preoperative assessment of ventricular function difficult [ 8 ] . If a large systemic-to-pulmonary shunt
is also present and contributing to the AV valve regurgitation by volume overload, the assessment of AV valve
function is further confused. Under these circumstances
it may be virtually impossible preoperatively to separate
the individual effects of valvar regurgitation and systemic-to-pulmonary artery shunts on ventricular function. Although the degree of regurgitation of a single AV
valve can be quite accurately evaluated preoperatively,
this evaluation becomes more difficult if both AV valves
are affected. This problem occurred in patient 1, in
whom repeated contrast injections into a single ventricular chamber proved misleading because it suggested severe regurgitation of the RAVV alone.
If the AV regurgitation is thought to be significant
preoperatively, repair or replacement should be undertaken at the time of the atriopulmonary procedure.
However, if the AV regurgitation is predicted to be mild
postoperatively, AVV function can be assessed intraoperatively by inspecting the valve and testing its
competence by passively filling the ventricle. If the function seems adequate, a conservative approach can be
considered and an F-K procedure performed. However,
after weaning from bypass, high mean left atrial pressure and tall V waves in the left atrial tracings indicate
the need for AVV repair or replacement. The need for
AV valve repair or replacement can only be made by
hemodynamic evaluation after shunt ligation and Fontan anastomosis have reduced the effects of volume
overload. AV valve repair and the F-K procedure should
be considered early in patients with AVV regurgitation
so that deterioration of ventricular function by volume
overload can be prevented. Also, because even small
elevations of left atrial pressure can be dangerous after
an F-K procedure, the type and size of prosthesis should
be chosen to provide a minimal gradient.
Although the preoperative evaluation of these patients can be difficult, simultaneous F-K operation and
AV valve repair or replacement is possible and has permitted a relatively normal life (NYHA Functional Class I)
in 3 patients over a short follow-up period.
References
1. Choussat A, Fontan F, Besse P, et al: Selection criteria for
Fontan procedure. In Anderson RH, Shinebourne EA (eds):
Pediatric Cardiology. Edinburgh, Churchill Livingstone,
1978, pp 559-566
2. Kreutzer G, Vargas FJ, Schlichter AJ, et al: Atriopulmonary
anastomosis. J Thorac Cardiovasc Surg 83:427, 1982
3. Marcelletti C, Mazzera E, Olthof H, et al: Fontan’s operation:
an expanded horizon. J Thorac Cardiovasc Surg 80:764, 1980
4. Di Carlo D, Marcelletti C, Nijved A, et al: The Fontan procedure in the absence of the interatrial septum: failure of its
principle? J Thorac Cardiovasc Surg 85:923, 1983
5. Van Praagh R, Plat JA, Van Praagh S: Single ventricle,
pathology, embriology, terminology and description. Herz
4:113, 1979
6. Bharati S, Lev M: The surgical anatomy of hypoplasia of the
aortic tract complex. J Thorac Cardiovasc Surg 88:97, 1984
7. Lang P, Jonas RA, Norwood WI, et al: The surgical anatomy
of hypoplasia of aortic tract complex. J Thorac Cardiovasc
Surg 89:149, 1985 (Letter)
8. Mair DD, Rice MJ, Hagler DJ, et al: Outcome of the Fontan
procedure in patients with tricuspid atresia. Circulation (Part
11) 7288, 1985
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