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The parachute mitral valve complex
The parachute mitral valve complex Case report and review of the literature A l Osmonth-old infant, the youngest patient thus far reported to have undergone successful correction of the developmental complex known as "parachute mitral valve," is presented. Severe mitral incompetence and aortic coarctation led to recurrent cardiac failure. Both anomalies were corrected in a one-stage procedure wherein the coarctation was resected under normothermia and the mitral valve replaced thereafter by a prosthesis employing deep hypothermia and total circulatory arrest. He made an uneventful recovery. Forty-two reported cases in the literature are reviewed and the pathologic and clinical features, diagnosis, natural history, and management briefly summarized.
A. Schachner, M.D., I. Varsano, M.D., and Morris J. Levy, M.D., Tel-Aviv, Israel
A
congenital entity called "parachute mitral valve" is a condition in which the chordae tendineae converge to insert into a single papillary muscle, causing severe stenosis, insufficiency, or both early in life. Often other obstructive left heart anomalies are additionally present, such as coarctation, bicuspid aortic valve, sub aortic stenosis, or supravalvular mitral stenosis, as components of a maldevelopmental complex. A 100month-old male infant who presented with recurrent severe bouts of congestive cardiac failure, respiratory infections, and failure to thrive was found to be suffering from a forme fruste of the parachute mitral complex, namely, severe coarctation of the aorta and a parachute deformity of the mitral valve which had led to mitral incompetence. Of the 43 cases that have been reported in the literature (including the present one) From the Thoracic-Cardiovascular Surgery Department, Beilinson Hospital, University of Tel-Aviv Medical School, Israel. Received for publication Jan. 2, 1975. Address for reprints: Morris J. Levy, M.D., ThoracicCardiovascular Surgery Department, Beilinson Hospital, University of Tel-Aviv Medical School, Tel-Aviv, Israel.
27 patients were operated upon and 12 survived. This report describes the youngest and the first to be successfully treated by mitral valve replacement and resection of coarctation at the age of 10 months. Case report Ch. S., who weighed 3 kilograms at birth after a normal pregnancy and delivery, was readmitted at the age of 9 months to the pediatric department because of shortness of breath, cough, and fever. There was no family history of congenital heart disease. He had first been admitted to the pediatric department 8 days after birth in acute respiratory distress and was then found to be in overt cardiac failure with hepatosplenomegaly and pitting edema of the legs. A gallop rhythm was present but no cardiac murmurs could be clearly identified at that stage. His condition improved markedly after treatment with digitalis. A Grade 3/6 harsh systolic murmur was heard for the first time at the age of 2 months at the left sternal border in the third intercostal space and was also audible over the left scapula. Blood pressure of 100 mm. Hg (systolic) was recorded in both arms, and neither femoral pulse could be palpated. A tentative diagnosis of coarctation of the aorta was made. His stay in the hospital, which lasted 3 months, was complicated by recurrent episodes of respiratory infection, intermittent cardiac decompensation, and failure to thrive. At the age of 3 months,
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Fig. 1. Preoperative chest x-ray radiography and angiography. Left: Significant enlargement of the heart with a plethora of the lung vasculature. Right: Left ventriculography with catheter inserted via the right brachial artery. Contrast material injected in the left ventricle demonstrates opacity retrogradely, with huge left atrium indicating severe mitral insufficiency. an inguinal herniotomy for an incarcerated right inguinal hernia was performed with no complications. On readmission at 9 months he was dyspneic at rest, with sinus pulse and rate of 120 beats per minute. A blood pressure of 140 mm Hg was recorded in both arms. There was moderate jugular vein engorgement and the liver was enlarged to the umbilicus. A systolic thrill was palpable over the precordium. A Grade 4/6 harsh pansystolic murmur was audible over the whole precordium but loudest at the lower left sternal border. There was normal splitting of the second sound. The electrocardiogram (ECG) showed sinus rhythm at 120 beats per minute, right axis deviation (+110°), and notched P waves indicative of left atrial enlargement. X-ray of the chest showed significant cardiomegaly with pulmonary vascular congestion. An enormously enlarged left atrium was seen to displace the esophagus posteriorly and also to have caused widening of the angle of the tracheal bifurcation (Fig. 1). The findings were consistent with mitral valve disease and coarctation. The child's condition deteriorated despite vigorous medical treatment and 10 days after admission he developed severe respiratory distress. The left main bronchus was seen on x-ray of the chest to be totally occluded by the enlarged left atrium. This had led to atelectasis of the left lung, leading to a marked degree of compensatory emphysema of the right lung, the upper part of which had herniated to the left side (Fig. 2). Cardiac catheterization revealed left ventricular pressure of 100/35 mm. Hg and 100/64 mm. Hg in the ascending aorta. At angiocardiography, the left ventricular injection resulted in rapid retrograde
opacification of a huge left atrium, indicating a grade 4 degree of regurgitation of the mitral valve. The ascending aorta was slightly dilated, with a coarctation present just distal to the origin of the left subclavian artery. At the age of 10 months (weight 5 kilograms) he was operated on under deep hypothermia with total circulatory arrest, with the use of the Barrat-Boyes and the Kyoto University Group techniques.v- 2 The chest was opened through a left lateral incision. During the first stage the coarctation was resected under normal temperature and the continuity of the aorta restored by endto-end anastomosis. The excised narrowed segment was 0.5 em. in length and about 2 mm. in diameter. The second stage consisted of connecting the infant to the extracorporeal circulation utilizing one drainage catheter in the right atrium and one return catheter in the ascending aorta. Cardiopulmonary bypass was commenced and the infant's temperature was lowered to 22° C., measured in the esophagus. After total circulatory arrest had been secured, the left atrium was opened and the mitral valve visualized. The mitral orifice measured about 15 mm. and had the form of a "parachute," namely, both leaflets were of normal appearance but the chordae tendineae coverged to insert into a single papillary muscle, the cause of the mitral valve dysfunction. After excision of both leaflets, the mitral valve was replaced by a size 00 Starr-Edwards prosthesis, of which the external diameter measured 1.7 em. and the orifice had an area of 1.3 sq. em. The period of total circulatory arrest lasted 35 minutes. The infant made an uneventful recovery with normal expansion of the previously atelectatic
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Fig. 2. Chest AP radiography. Left: The preoperative status of the heart and lungs. Note the atelectasis of the left lung with displacement of the heart to the left and herniation of the upper parts of the right lung toward the left side. Right: Postoperative chest radiography showing normal position of the heart and mediastinum wtih a mitral valve prosthesis.
left lung immediately after operation. By the third postoperative day anticoagulant therapy was begun, with dipyridamole, 25 mg. twice a day and acetylsalicylic acid 0.1 per day. At present, 8 months following the operation, his weight is 9.5 kilograms and he is completely asymptomatic.
Comment The above anomaly was first reported by Swan and associates- in 1949; they described it as "funnel-shaped" stenosis of the mitral valve. In 1961 Schiebler and associates" introduced the term "parachute deformity" because of the resemblance of the valve apparatus to the structure of a parachute. Subsequently, Shone and his coworkers' described it as a developmental complex in order to emphasize the frequently associated malformations-supravalvular stenosing ring of the left atrium, parachute deformity of the mitral valve, subaortic stenosis, and coarctation of the aorta . Those cases with three or fewer of the above lesions were considered as formes frustes of the same complex. It should be noted that other malformations such as ventricular septal defect, patent ductus arteriosus, complete or corrected transposition of the great vessels, and coronary artery anomalies may coexist with the above complex and contribute to the high operative mor-
tality rate and short life expectancy under conservative treatment. 5 , 8, 9 Though the relationship is recognized, it is useful to differentiate between those cases wherein the parachute deformity of the mitral valve forms the main lesion (Table I) and those in which a supravalvular stenosing ring of the mitral valve dominates the clinical picture (Table II). So far a total of 40 cases of parachute mitral valve complex have been reported in the literature. It is noteworthy that in no patient with this deformity was an associated atrial septal defect found. This observation led Lev and Killian'? to suggest that premature closure of the foramen ovale in the fetus may lead to underdevelopment of the left side of the heart, which may be represented by one or more of the above-described anomalies. In reviewing the 40 cases of the parachute mitral valve complex the following points are noteworthy. Although the patients' ages ranged from 3 months to 33 years, the majority (75 per cent) were less than 10 years of age. There was no predilection for either sex. Parachute deformity of the mitral valve was the most frequently encountered component of this complex (75 per cent), with supravalvular stenosing ring of the left atrium, coarctation of the aorta,
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Table I. Thirty documented cases of parachute deformity of the mitral valve in relation to age, sex, associated lesions, and outcome of operation Supravalvular stenosis Parachute (ring) of deformity mitral ofmitral Subaortic Coarctation Associated Case Ref No. No. Sex Age valve valve ofaorta lesions" stenosis
5 6
1 F 2 M 3 M
18 33 15
+ +
24 7
4 M
11 14
5 6 7 8 9
28
10
F
5
+
20
11 M
7
12 13 14 15 16
9 7 9
+ +
18 29 15
30
8
13
Present case
I''/,.
M 4 F 13"/,. M 22 M 3"/,. M 22
M M M F M
17 M 18 F 19 M 20 M 21 F
11 5
6 2"/,. 2 3
25 F 26 F 27 F 28 F 29 M 30 M
+
+ +
+ +
9 15 10 8 2
"y..
+
+ +
+ +
+ + +
+
+
+ +
+ + +
+ + + +
+
+ +
+ +
+ + + + + +
+
+
+ + +
+ +
+
+
+
+ + + + +
+ +
+ +
PLSVC, single ventricle BAV BAV BAV BAV BAV BAV
+ +
+
+ +
+MC +MC
+ +
+
+MVR,AV +MVR,AV +MVR,AV +MVR,AV
%.+ resection of coarctation 5+ excision of ring
Died Alive
+ + + +
+ + +
+
+
+
VSD PS
+
+Closure ofVSD + MVR + pulmonic valvotomy
+
+
+ + +
+
+ + +
+ MVR + resection of coarctation
+ + +
+
?
PDA
+ +
+MC BAV +MC PS +MC BAV,PDA, PLSVC, Resection of VSD coarctation
+ +
+
Operation*
+MVR + MVR + excision of ring
+
+ +
"I..
22 M 22 23 F 6 24 F 4
+
+
+
PDA CTGA CTGA PLSVS BAV BAV VSD, BPV
+
+ +
'PDA, Patent ductus arteriosus; VSD, ventricular septal defect; CTGA, corrected transposition of great arteries; BAV, bicuspid aortic valve; PLSVC, persistent left superior vena cava; MVR, mitral valve replacement; MC, mitral commissurotomy; OMC, open mitral commissurotomy; PS, pulmonic stenosis; AV, aortic valuloplasty.
and subaortic stenosis occurring in 55, 52.5, and 35 per cent, respectively. The incidence of other coexisting cardiac anomalies was high, with about 30 per cent of the cases having bicuspid aortic valve and a similar number of patients hav-
ing either one or several of the following lesions: ventricular septal defect, persistent left superior vena cava, and patent ductus arteriosus. Eleven of the 16 patients who were not treated surgically died early in life. Of
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Table II. Ten documented cases of supravalvular stenosis (ring) of the mitral valve
Case Ref No. No. Sex 9
1 2
23 25 26
4
7
5
3
6 7 27 16
8 9
10
F F M M F M F F M M
Age
8/"
2 17 11
8/ " 7/,.
3Y,. "/,. 2"/"
y"
Supra valvular stenosis Subaortic Coarctation (ring) of .mitral valve ofaorta stenosis + + + + + + + + + +
+
+ + + +
+ +
Associated lesions*
Operation
VSD + BAV, PLSVC+ + Excision of ring, VSD closure of VSD BAV VSD BAV PLSVC + Excision of ring
Died
Alive
+ + + + + + + + + +
• Abbreviations as in Table I.
the 27 who were operated on, 12 survived and 15 died. Eight of the twelve survivors were subjected to mitral valve replacement, the first one operated by one of us (M. J. L.) in 1964 and reported by Prado and associatesY The hemodynamic derangements in this syndrome are due to the presence of several coexisting lesions affecting the left side of the heart and therefore depend on the degree of obstruction. The varying combinations of lesions lead to a correspondingly wide diversity of clinical manifestations and for this reason the diagnosis of the parachute mitral valve complex has seldom been established prior to operation or autopsy among the earlier reported cases. Lately, however, Deutch and associates" reported on eight cases in which the diagnosis was established in five patients and confirmed by angiography or after death. It should be noted that the complex may exist without the peculiar deformity of the mitral valve and, on the other hand, the parachute deformity may exist as an isolated defect.v- 12 In most of the cases reported in the literature, the mitral valve leaflets and commissures appeared normal when explored from the left atrium. However, the chordae tendineae may be normal or occasionally short and thick, thus impairing the mobility of the leaflets. The most important feature, however, is that the chordae converge either
into a single papillary muscle or into one muscular mass formed by two adjacent papillary muscles. The mitral valve dysfunction, therefore, may manifest itself hemodynamically as either mitral stenosis, regurgitation, or both. 1 3 - 1 5 The supravalvular stenosing ring is described as a circumferential connective tissue ridge in the left atrium just above the mitral valve. In its most fully developed form it can constitute a severe obstruction to blood flow, but it may sometimes be present in only rudimentary degree. The hypothesis that this ridge is the result of a regurgitant jet would seem to be unlikely in view of the fact that it may exist on occasion as an isolated lesion and also because it may form part of a complex which does not include mitral regurgitation." The condition must be clearly separated from that of cor triatriatum in which a stenotic membrane is present above the foramen ovale which divides the left atrium into two compartments. The supravalvular stenosing ring in this complex is always located below the foramen ovale. The third stenotic lesion encountered in this complex anomaly may present as either a muscular or a membranous form of subaortic stenosis. Rarely both types may occur simultaneously. Varying degrees of coarctation of the aorta are encountered frequently as the fourth component of this anomaly. It is
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generally the first lesion to be recognized clinically and this, together with physical findings of disease of the mitral valve, should alert the physican to the possibility of the whole developmental complex. In the case presented above, the diagnosis of coarctation was established at the age of 10 days but only at the age of 9 months was mitral valve disease first suspected and confirmed at catheterization, although a heart murmur suspicious for mitral insufficiency was first noted at the age of 2 months. Although sometimes difficult because of the multiplicity of the lesions, correct diagnosis is of the utmost importance once surgical correction is considered. No specific EeG pattern could be identified, but the presence of biatrial and biventricular hypertrophy should serve as important clues to the possibility of this condition. 7, 8, 15 Plain chest x-ray may show moderate to marked cardiac enlargement with prominence of the left ventricle and with moderate to marked left atrial enlargement." In the case presented above, the degree of left atrial enlargement was so gross that it produced compression of the left main stem bronchus with resultant atelectasis of the left lung. This was promptly relieved after surgical correction of the cardiac anomaly. The most valuable confirmation tests are those of cardiac catheterization and angiocardiography, which will usually reveal the hemodynamic and anatomic features of the complex.>'- 13, 17, 18 On left ventriculography a sickle-shaped translucency in the mitral valve area is considered characteristic of the presence of a supravalvular stenosing ring. However, the most frequently observed angiocardiographic feature, as noted in the literature, is the filling defect caused by the hypertrophied and abnormally located papillary muscle. In our case, and in similar cases in the literature, this radiologic sign was absent. One may thus speculate that the muscular hypertrophy derives from the abnormal work load imposed on the single papillary muscle, and that this would become radiologically evident only at a somewhat older age.
Thoracic and Cardiovascular Surgery
It is generally agreed that this developmental complex, if symptomatic, should be treated surgically in all age groups. Mitral commissurotomy as a surgical treatment for the parachute deformity has proved to be ineffective and in the majority of instances when this was employed it produced most disappointing results.'>?" The correct operation, regardless of age, has been proved (Table I) to be valve replacement by a prosthesis.>'- 14, 20 On the other hand, mitral valve replacement may be somewhat problematic in the pediatric age groups because of the fixed diameter of the prosthesis in relation to the growing child and the need for continuous anticoagulant therapy. These problems are still further accentuated in infants who will require subsequent multiple replacement of the mitral prosthesis as they grow. As for the anticoagulant treatment, in our own experience with other children and that reported by others, the combination of dipyridamole and salicylates constitutes an effective and reliable form of anticoagulant therapY,21, 22 avoiding the need for frequent prothrombin time tests and the potential danger of bleeding when coumarin derivatives are used. As far as we can ascertain from the literature available to us, the case reported herein would appear to be the youngest patient successfully operated on for parachute mitral valve complex, namely, resection of coarctation and mitral valve replacement in a one-stage operation."?" REFERENCES Schachner, A., Levy, E., and Levy, M. J.: Deep Hypothermia and Total Circulatory Arrest; Experience With Congenital Heart Lesions in Neonates and Infants, Harefuah 87: 291, 1974. 2 Barrat-Boyes, B. G., Neutze, I. M., and Harris, E. A., editors: Heart Disease in Infancy: Diagnosis and Surgical Treatment; Proceedings of the Second International Symposium, London, 1973, Churchill Livingstone. 3 Barrat-Boyes, B. G., Simpson, M., and Neutze, I. M.: Intracardiac Surgery in Neonates and Infants Using Deep Hypothermia With Surface Cooling and Limited Cardiopulmonary Bypass, Circulation 43 (Suppl. 1): 25, 1971.
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4 Horiuchi, T., Koyamada, K., Matano, I., Mohri, H., Komatsy, T., Honda, T., Abe, T., Ishitoya, T., Sagawa, Y., Matsumura, M., Tsuda, T., Ishizawa, E., Ishikawa, Sh., Suzuki, H., and Saito, I.: Radical Operation for V.S.D. in Infancy, J. THORAc. CARDIOVASC. SURG. 46: 180, 1963. 5 Swan, H., Trapnell, I. M., and Dent, I.:Congenital Mitral Stenosis and Systemic Right Ventricle With Associated Pulmonary Vascular Changes Frustrating Surgical Repair of Patent Ductus Arteriosus and Coarctation of the Aorta, Am. Heart J. 38: 914, 1949. 6 Schiebler, G. L., Edwards, J. E., Burchell, H. B., DuShane, J. W., Ongley, P. A., and Wood, E. H.: Congenital Corrected Transposition of the Great Vessels. A Study of 33 Cases, Pediatrics 27 (Supp!.): 851, 1961. 7 Shone, D. J., Sellers, R. D., Anderson, R. C., Adams, P., Lillehei, C. W., and Edwards, J. E.: The Developmental Complex of Parachute Mitral Valve, Supravalvular Ring of the Left Atrium Subaortic Stenosis and Coarctation of the Aorta, Am. J. Cardiel, 11: 714, 1963. 8 Glancy, D. L., Chang, M. Y., Dorney, E. R., and Roberts, W. C.: Parachute Mitral Valve. Further Observation and Associated Lesions, Am. J. Cardio!. 27: 309, 1971. 9 Rogers, H. M., Waldron, R., Murphey, D. F. H., and Edwards, J. E.: Supravalvular Stenosing Ring of Left Atrium in Association With Endocardial Sclerosis and Mitral Insufficiency, Am. Heart J. 50: 777, 1955. 10 Lev, M., and Killian, S.: Hypoplasia of the Aorta Without Transposition With Electrocardiographic and Histopathologic Studies of the Conduction System, Am. Heart J. 24: 724, 1942. 11 Prado, S., Levy, M., and Varco, R. L.: Successful Replacement of "Parachute" Mitral Valve in a Child, Circulation 32: 130, 1965. 12 Azpitarte, J., Castrillo, J. M., and Sokolowski, M.: Valvula Mitral en Paracaidas, Rev. Esp. Cardio!. 24: 499, 1971. 13 Deutch, V., Yahini, J. H., Shem-Tov, A., and Neufeld, H. N.: The Parachute Mitral Valve Complex. Angiographic Observations, Chest 65: 262, 1974. 14 Anabtawi, I. N., and Ellison, R. G.: Congenital Stenosing Ring of the Left Artioventricular Canal, J. THoRAc. CARDIOVASC. SURG. 49: 994, 1965. 15 Khoury, G., Hawes, C. R., and Grow, J.: Coarctation of the Aorta With Obstructive Anomalies of the Mitral Valve and Left Ventricle, J. Pediatr. 75: 652, 1969. 16 Chung, K. J., Manning, J. A., Lipchik, E. 0., Graniak, R., and Mahoney, E. F.: Isolated Supravalvular Stenosing Ring of the Left
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19 20
21 22
23 24
25
26
27
28
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Atrium: Diagnosis before operation and successful surgical treatment, Chest 65: 25, 1974. Carey, L. S., Sellers, R. D., and Shone, J. D.: Radiologic Findings in the Developmental Complex of Parachute Mitral Valve, Repair of Patent Ductus Arteriosus and Coarctation of the Aorta, Am. Heart J. 38: 914, 1949. ZamaIloa, 0., Franceschi, A. de, and Leachman, R. D.: Clinical and Angiographic Diagnosis of the Parachute Mitral Valve, Acta Cardio!. (Brux.) 24: 101, 1969. MaIm, J. R., Bowman, F. 0., Jesse, M. J., and Blumenthal, S.: Open Heart Surgery in the Infant, Am. J. Surg. 119: 613, 1970. Terzaki, A. K., Leachman, R. D., KhaIil, A. M., Hailman, G. L., and Cooley, D. A.: Successful Surgical Treatment for the Parachute Mitral Valve Complex, J. Thorac. Cardiovasc. Surg, 56: 1, 1968. O'Brien, J. R.: Effect of Salicylates on Blood Platelets, Lancet 1: 779, 1968. Emmons, P. R., Harrison, M. J. G., and Honour, A. J.: Effect of Dipyridamole on Human PlatIet Behaviour, Lancet 2: 603, 1965. Manubens, R., Krovetz, L. J., and Adams, P.: Supravalvular Stenosing Ring of the Left Atrium, Am. Heart J. 60: 286, 1960. El Sayed, H., Cleland, V. P., BentaIl, H. H., Melrose, D. G., Bishop, M. B., and Morgan, J.: Corrected Transposition of the Great Arterial Trunks: Surgical Treatment of the Associated Defects, J. THORAC. CARDIOVASC. SURG. 44: 443, 1962. Stretton, T. B., and Fentem, P. H.: Stenosis of the Left Atrioventricular Canal, Br. Heart J. 24: 237, 1962. Lynch, M. F., Ryan, N. J., and Williams, G. R.: Preoperative Diagnosis and Surgical Correction of Supravalvular Mitral Stenosis and Ventricular Septal Defect, Circulation 25: 854, 1962. Cassano, G. B.: Congenital Annular Stenosis of the Left Atrioventricular Canal, So-Cailed Supravalvular Mitral Stenosis, Am. J. Cardio!. 13: 708, 1964. Sancher Cascos, A., Rabago, P., Sokolowski, M., and Varela de Seijas, J. R.: Subvalvular Congenital Mitral Stenosis, Br. Heart J. 28: 808, 1966. Bett, J. H. N., and Stovin, P. G. I.: Parachute Deformity of the Mitral Valve, Thorax 24: 362, 1969. Easthope, R. N., Tawes, R. L., BonhamCarter, R. E., Aberdeen, E., and Waterstone, D. J.: Congenital Mitral Valve Disease Associated With Coarctation of the Aorta. A Report of 39 Cases, Am. Heart 1. 77: 743, 1969.
A. Schachner, M.D., I. Varsano, M.D., and Morris J. Levy, M.D., Tel-Aviv, Israel
A
congenital entity called "parachute mitral valve" is a condition in which the chordae tendineae converge to insert into a single papillary muscle, causing severe stenosis, insufficiency, or both early in life. Often other obstructive left heart anomalies are additionally present, such as coarctation, bicuspid aortic valve, sub aortic stenosis, or supravalvular mitral stenosis, as components of a maldevelopmental complex. A 100month-old male infant who presented with recurrent severe bouts of congestive cardiac failure, respiratory infections, and failure to thrive was found to be suffering from a forme fruste of the parachute mitral complex, namely, severe coarctation of the aorta and a parachute deformity of the mitral valve which had led to mitral incompetence. Of the 43 cases that have been reported in the literature (including the present one) From the Thoracic-Cardiovascular Surgery Department, Beilinson Hospital, University of Tel-Aviv Medical School, Israel. Received for publication Jan. 2, 1975. Address for reprints: Morris J. Levy, M.D., ThoracicCardiovascular Surgery Department, Beilinson Hospital, University of Tel-Aviv Medical School, Tel-Aviv, Israel.
27 patients were operated upon and 12 survived. This report describes the youngest and the first to be successfully treated by mitral valve replacement and resection of coarctation at the age of 10 months. Case report Ch. S., who weighed 3 kilograms at birth after a normal pregnancy and delivery, was readmitted at the age of 9 months to the pediatric department because of shortness of breath, cough, and fever. There was no family history of congenital heart disease. He had first been admitted to the pediatric department 8 days after birth in acute respiratory distress and was then found to be in overt cardiac failure with hepatosplenomegaly and pitting edema of the legs. A gallop rhythm was present but no cardiac murmurs could be clearly identified at that stage. His condition improved markedly after treatment with digitalis. A Grade 3/6 harsh systolic murmur was heard for the first time at the age of 2 months at the left sternal border in the third intercostal space and was also audible over the left scapula. Blood pressure of 100 mm. Hg (systolic) was recorded in both arms, and neither femoral pulse could be palpated. A tentative diagnosis of coarctation of the aorta was made. His stay in the hospital, which lasted 3 months, was complicated by recurrent episodes of respiratory infection, intermittent cardiac decompensation, and failure to thrive. At the age of 3 months,
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Fig. 1. Preoperative chest x-ray radiography and angiography. Left: Significant enlargement of the heart with a plethora of the lung vasculature. Right: Left ventriculography with catheter inserted via the right brachial artery. Contrast material injected in the left ventricle demonstrates opacity retrogradely, with huge left atrium indicating severe mitral insufficiency. an inguinal herniotomy for an incarcerated right inguinal hernia was performed with no complications. On readmission at 9 months he was dyspneic at rest, with sinus pulse and rate of 120 beats per minute. A blood pressure of 140 mm Hg was recorded in both arms. There was moderate jugular vein engorgement and the liver was enlarged to the umbilicus. A systolic thrill was palpable over the precordium. A Grade 4/6 harsh pansystolic murmur was audible over the whole precordium but loudest at the lower left sternal border. There was normal splitting of the second sound. The electrocardiogram (ECG) showed sinus rhythm at 120 beats per minute, right axis deviation (+110°), and notched P waves indicative of left atrial enlargement. X-ray of the chest showed significant cardiomegaly with pulmonary vascular congestion. An enormously enlarged left atrium was seen to displace the esophagus posteriorly and also to have caused widening of the angle of the tracheal bifurcation (Fig. 1). The findings were consistent with mitral valve disease and coarctation. The child's condition deteriorated despite vigorous medical treatment and 10 days after admission he developed severe respiratory distress. The left main bronchus was seen on x-ray of the chest to be totally occluded by the enlarged left atrium. This had led to atelectasis of the left lung, leading to a marked degree of compensatory emphysema of the right lung, the upper part of which had herniated to the left side (Fig. 2). Cardiac catheterization revealed left ventricular pressure of 100/35 mm. Hg and 100/64 mm. Hg in the ascending aorta. At angiocardiography, the left ventricular injection resulted in rapid retrograde
opacification of a huge left atrium, indicating a grade 4 degree of regurgitation of the mitral valve. The ascending aorta was slightly dilated, with a coarctation present just distal to the origin of the left subclavian artery. At the age of 10 months (weight 5 kilograms) he was operated on under deep hypothermia with total circulatory arrest, with the use of the Barrat-Boyes and the Kyoto University Group techniques.v- 2 The chest was opened through a left lateral incision. During the first stage the coarctation was resected under normal temperature and the continuity of the aorta restored by endto-end anastomosis. The excised narrowed segment was 0.5 em. in length and about 2 mm. in diameter. The second stage consisted of connecting the infant to the extracorporeal circulation utilizing one drainage catheter in the right atrium and one return catheter in the ascending aorta. Cardiopulmonary bypass was commenced and the infant's temperature was lowered to 22° C., measured in the esophagus. After total circulatory arrest had been secured, the left atrium was opened and the mitral valve visualized. The mitral orifice measured about 15 mm. and had the form of a "parachute," namely, both leaflets were of normal appearance but the chordae tendineae coverged to insert into a single papillary muscle, the cause of the mitral valve dysfunction. After excision of both leaflets, the mitral valve was replaced by a size 00 Starr-Edwards prosthesis, of which the external diameter measured 1.7 em. and the orifice had an area of 1.3 sq. em. The period of total circulatory arrest lasted 35 minutes. The infant made an uneventful recovery with normal expansion of the previously atelectatic
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Fig. 2. Chest AP radiography. Left: The preoperative status of the heart and lungs. Note the atelectasis of the left lung with displacement of the heart to the left and herniation of the upper parts of the right lung toward the left side. Right: Postoperative chest radiography showing normal position of the heart and mediastinum wtih a mitral valve prosthesis.
left lung immediately after operation. By the third postoperative day anticoagulant therapy was begun, with dipyridamole, 25 mg. twice a day and acetylsalicylic acid 0.1 per day. At present, 8 months following the operation, his weight is 9.5 kilograms and he is completely asymptomatic.
Comment The above anomaly was first reported by Swan and associates- in 1949; they described it as "funnel-shaped" stenosis of the mitral valve. In 1961 Schiebler and associates" introduced the term "parachute deformity" because of the resemblance of the valve apparatus to the structure of a parachute. Subsequently, Shone and his coworkers' described it as a developmental complex in order to emphasize the frequently associated malformations-supravalvular stenosing ring of the left atrium, parachute deformity of the mitral valve, subaortic stenosis, and coarctation of the aorta . Those cases with three or fewer of the above lesions were considered as formes frustes of the same complex. It should be noted that other malformations such as ventricular septal defect, patent ductus arteriosus, complete or corrected transposition of the great vessels, and coronary artery anomalies may coexist with the above complex and contribute to the high operative mor-
tality rate and short life expectancy under conservative treatment. 5 , 8, 9 Though the relationship is recognized, it is useful to differentiate between those cases wherein the parachute deformity of the mitral valve forms the main lesion (Table I) and those in which a supravalvular stenosing ring of the mitral valve dominates the clinical picture (Table II). So far a total of 40 cases of parachute mitral valve complex have been reported in the literature. It is noteworthy that in no patient with this deformity was an associated atrial septal defect found. This observation led Lev and Killian'? to suggest that premature closure of the foramen ovale in the fetus may lead to underdevelopment of the left side of the heart, which may be represented by one or more of the above-described anomalies. In reviewing the 40 cases of the parachute mitral valve complex the following points are noteworthy. Although the patients' ages ranged from 3 months to 33 years, the majority (75 per cent) were less than 10 years of age. There was no predilection for either sex. Parachute deformity of the mitral valve was the most frequently encountered component of this complex (75 per cent), with supravalvular stenosing ring of the left atrium, coarctation of the aorta,
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Thoracic and Cardiovascular Surgery
Table I. Thirty documented cases of parachute deformity of the mitral valve in relation to age, sex, associated lesions, and outcome of operation Supravalvular stenosis Parachute (ring) of deformity mitral ofmitral Subaortic Coarctation Associated Case Ref No. No. Sex Age valve valve ofaorta lesions" stenosis
5 6
1 F 2 M 3 M
18 33 15
+ +
24 7
4 M
11 14
5 6 7 8 9
28
10
F
5
+
20
11 M
7
12 13 14 15 16
9 7 9
+ +
18 29 15
30
8
13
Present case
I''/,.
M 4 F 13"/,. M 22 M 3"/,. M 22
M M M F M
17 M 18 F 19 M 20 M 21 F
11 5
6 2"/,. 2 3
25 F 26 F 27 F 28 F 29 M 30 M
+
+ +
+ +
9 15 10 8 2
"y..
+
+ +
+ +
+ + +
+
+
+ +
+ + +
+ + + +
+
+ +
+ +
+ + + + + +
+
+
+ + +
+ +
+
+
+
+ + + + +
+ +
+ +
PLSVC, single ventricle BAV BAV BAV BAV BAV BAV
+ +
+
+ +
+MC +MC
+ +
+
+MVR,AV +MVR,AV +MVR,AV +MVR,AV
%.+ resection of coarctation 5+ excision of ring
Died Alive
+ + + +
+ + +
+
+
+
VSD PS
+
+Closure ofVSD + MVR + pulmonic valvotomy
+
+
+ + +
+
+ + +
+ MVR + resection of coarctation
+ + +
+
?
PDA
+ +
+MC BAV +MC PS +MC BAV,PDA, PLSVC, Resection of VSD coarctation
+ +
+
Operation*
+MVR + MVR + excision of ring
+
+ +
"I..
22 M 22 23 F 6 24 F 4
+
+
+
PDA CTGA CTGA PLSVS BAV BAV VSD, BPV
+
+ +
'PDA, Patent ductus arteriosus; VSD, ventricular septal defect; CTGA, corrected transposition of great arteries; BAV, bicuspid aortic valve; PLSVC, persistent left superior vena cava; MVR, mitral valve replacement; MC, mitral commissurotomy; OMC, open mitral commissurotomy; PS, pulmonic stenosis; AV, aortic valuloplasty.
and subaortic stenosis occurring in 55, 52.5, and 35 per cent, respectively. The incidence of other coexisting cardiac anomalies was high, with about 30 per cent of the cases having bicuspid aortic valve and a similar number of patients hav-
ing either one or several of the following lesions: ventricular septal defect, persistent left superior vena cava, and patent ductus arteriosus. Eleven of the 16 patients who were not treated surgically died early in life. Of
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455
Table II. Ten documented cases of supravalvular stenosis (ring) of the mitral valve
Case Ref No. No. Sex 9
1 2
23 25 26
4
7
5
3
6 7 27 16
8 9
10
F F M M F M F F M M
Age
8/"
2 17 11
8/ " 7/,.
3Y,. "/,. 2"/"
y"
Supra valvular stenosis Subaortic Coarctation (ring) of .mitral valve ofaorta stenosis + + + + + + + + + +
+
+ + + +
+ +
Associated lesions*
Operation
VSD + BAV, PLSVC+ + Excision of ring, VSD closure of VSD BAV VSD BAV PLSVC + Excision of ring
Died
Alive
+ + + + + + + + + +
• Abbreviations as in Table I.
the 27 who were operated on, 12 survived and 15 died. Eight of the twelve survivors were subjected to mitral valve replacement, the first one operated by one of us (M. J. L.) in 1964 and reported by Prado and associatesY The hemodynamic derangements in this syndrome are due to the presence of several coexisting lesions affecting the left side of the heart and therefore depend on the degree of obstruction. The varying combinations of lesions lead to a correspondingly wide diversity of clinical manifestations and for this reason the diagnosis of the parachute mitral valve complex has seldom been established prior to operation or autopsy among the earlier reported cases. Lately, however, Deutch and associates" reported on eight cases in which the diagnosis was established in five patients and confirmed by angiography or after death. It should be noted that the complex may exist without the peculiar deformity of the mitral valve and, on the other hand, the parachute deformity may exist as an isolated defect.v- 12 In most of the cases reported in the literature, the mitral valve leaflets and commissures appeared normal when explored from the left atrium. However, the chordae tendineae may be normal or occasionally short and thick, thus impairing the mobility of the leaflets. The most important feature, however, is that the chordae converge either
into a single papillary muscle or into one muscular mass formed by two adjacent papillary muscles. The mitral valve dysfunction, therefore, may manifest itself hemodynamically as either mitral stenosis, regurgitation, or both. 1 3 - 1 5 The supravalvular stenosing ring is described as a circumferential connective tissue ridge in the left atrium just above the mitral valve. In its most fully developed form it can constitute a severe obstruction to blood flow, but it may sometimes be present in only rudimentary degree. The hypothesis that this ridge is the result of a regurgitant jet would seem to be unlikely in view of the fact that it may exist on occasion as an isolated lesion and also because it may form part of a complex which does not include mitral regurgitation." The condition must be clearly separated from that of cor triatriatum in which a stenotic membrane is present above the foramen ovale which divides the left atrium into two compartments. The supravalvular stenosing ring in this complex is always located below the foramen ovale. The third stenotic lesion encountered in this complex anomaly may present as either a muscular or a membranous form of subaortic stenosis. Rarely both types may occur simultaneously. Varying degrees of coarctation of the aorta are encountered frequently as the fourth component of this anomaly. It is
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generally the first lesion to be recognized clinically and this, together with physical findings of disease of the mitral valve, should alert the physican to the possibility of the whole developmental complex. In the case presented above, the diagnosis of coarctation was established at the age of 10 days but only at the age of 9 months was mitral valve disease first suspected and confirmed at catheterization, although a heart murmur suspicious for mitral insufficiency was first noted at the age of 2 months. Although sometimes difficult because of the multiplicity of the lesions, correct diagnosis is of the utmost importance once surgical correction is considered. No specific EeG pattern could be identified, but the presence of biatrial and biventricular hypertrophy should serve as important clues to the possibility of this condition. 7, 8, 15 Plain chest x-ray may show moderate to marked cardiac enlargement with prominence of the left ventricle and with moderate to marked left atrial enlargement." In the case presented above, the degree of left atrial enlargement was so gross that it produced compression of the left main stem bronchus with resultant atelectasis of the left lung. This was promptly relieved after surgical correction of the cardiac anomaly. The most valuable confirmation tests are those of cardiac catheterization and angiocardiography, which will usually reveal the hemodynamic and anatomic features of the complex.>'- 13, 17, 18 On left ventriculography a sickle-shaped translucency in the mitral valve area is considered characteristic of the presence of a supravalvular stenosing ring. However, the most frequently observed angiocardiographic feature, as noted in the literature, is the filling defect caused by the hypertrophied and abnormally located papillary muscle. In our case, and in similar cases in the literature, this radiologic sign was absent. One may thus speculate that the muscular hypertrophy derives from the abnormal work load imposed on the single papillary muscle, and that this would become radiologically evident only at a somewhat older age.
Thoracic and Cardiovascular Surgery
It is generally agreed that this developmental complex, if symptomatic, should be treated surgically in all age groups. Mitral commissurotomy as a surgical treatment for the parachute deformity has proved to be ineffective and in the majority of instances when this was employed it produced most disappointing results.'>?" The correct operation, regardless of age, has been proved (Table I) to be valve replacement by a prosthesis.>'- 14, 20 On the other hand, mitral valve replacement may be somewhat problematic in the pediatric age groups because of the fixed diameter of the prosthesis in relation to the growing child and the need for continuous anticoagulant therapy. These problems are still further accentuated in infants who will require subsequent multiple replacement of the mitral prosthesis as they grow. As for the anticoagulant treatment, in our own experience with other children and that reported by others, the combination of dipyridamole and salicylates constitutes an effective and reliable form of anticoagulant therapY,21, 22 avoiding the need for frequent prothrombin time tests and the potential danger of bleeding when coumarin derivatives are used. As far as we can ascertain from the literature available to us, the case reported herein would appear to be the youngest patient successfully operated on for parachute mitral valve complex, namely, resection of coarctation and mitral valve replacement in a one-stage operation."?" REFERENCES Schachner, A., Levy, E., and Levy, M. J.: Deep Hypothermia and Total Circulatory Arrest; Experience With Congenital Heart Lesions in Neonates and Infants, Harefuah 87: 291, 1974. 2 Barrat-Boyes, B. G., Neutze, I. M., and Harris, E. A., editors: Heart Disease in Infancy: Diagnosis and Surgical Treatment; Proceedings of the Second International Symposium, London, 1973, Churchill Livingstone. 3 Barrat-Boyes, B. G., Simpson, M., and Neutze, I. M.: Intracardiac Surgery in Neonates and Infants Using Deep Hypothermia With Surface Cooling and Limited Cardiopulmonary Bypass, Circulation 43 (Suppl. 1): 25, 1971.
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Parachute mitral valve
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September, 1975
4 Horiuchi, T., Koyamada, K., Matano, I., Mohri, H., Komatsy, T., Honda, T., Abe, T., Ishitoya, T., Sagawa, Y., Matsumura, M., Tsuda, T., Ishizawa, E., Ishikawa, Sh., Suzuki, H., and Saito, I.: Radical Operation for V.S.D. in Infancy, J. THORAc. CARDIOVASC. SURG. 46: 180, 1963. 5 Swan, H., Trapnell, I. M., and Dent, I.:Congenital Mitral Stenosis and Systemic Right Ventricle With Associated Pulmonary Vascular Changes Frustrating Surgical Repair of Patent Ductus Arteriosus and Coarctation of the Aorta, Am. Heart J. 38: 914, 1949. 6 Schiebler, G. L., Edwards, J. E., Burchell, H. B., DuShane, J. W., Ongley, P. A., and Wood, E. H.: Congenital Corrected Transposition of the Great Vessels. A Study of 33 Cases, Pediatrics 27 (Supp!.): 851, 1961. 7 Shone, D. J., Sellers, R. D., Anderson, R. C., Adams, P., Lillehei, C. W., and Edwards, J. E.: The Developmental Complex of Parachute Mitral Valve, Supravalvular Ring of the Left Atrium Subaortic Stenosis and Coarctation of the Aorta, Am. J. Cardiel, 11: 714, 1963. 8 Glancy, D. L., Chang, M. Y., Dorney, E. R., and Roberts, W. C.: Parachute Mitral Valve. Further Observation and Associated Lesions, Am. J. Cardio!. 27: 309, 1971. 9 Rogers, H. M., Waldron, R., Murphey, D. F. H., and Edwards, J. E.: Supravalvular Stenosing Ring of Left Atrium in Association With Endocardial Sclerosis and Mitral Insufficiency, Am. Heart J. 50: 777, 1955. 10 Lev, M., and Killian, S.: Hypoplasia of the Aorta Without Transposition With Electrocardiographic and Histopathologic Studies of the Conduction System, Am. Heart J. 24: 724, 1942. 11 Prado, S., Levy, M., and Varco, R. L.: Successful Replacement of "Parachute" Mitral Valve in a Child, Circulation 32: 130, 1965. 12 Azpitarte, J., Castrillo, J. M., and Sokolowski, M.: Valvula Mitral en Paracaidas, Rev. Esp. Cardio!. 24: 499, 1971. 13 Deutch, V., Yahini, J. H., Shem-Tov, A., and Neufeld, H. N.: The Parachute Mitral Valve Complex. Angiographic Observations, Chest 65: 262, 1974. 14 Anabtawi, I. N., and Ellison, R. G.: Congenital Stenosing Ring of the Left Artioventricular Canal, J. THoRAc. CARDIOVASC. SURG. 49: 994, 1965. 15 Khoury, G., Hawes, C. R., and Grow, J.: Coarctation of the Aorta With Obstructive Anomalies of the Mitral Valve and Left Ventricle, J. Pediatr. 75: 652, 1969. 16 Chung, K. J., Manning, J. A., Lipchik, E. 0., Graniak, R., and Mahoney, E. F.: Isolated Supravalvular Stenosing Ring of the Left
17
18
19 20
21 22
23 24
25
26
27
28
29 30
Atrium: Diagnosis before operation and successful surgical treatment, Chest 65: 25, 1974. Carey, L. S., Sellers, R. D., and Shone, J. D.: Radiologic Findings in the Developmental Complex of Parachute Mitral Valve, Repair of Patent Ductus Arteriosus and Coarctation of the Aorta, Am. Heart J. 38: 914, 1949. ZamaIloa, 0., Franceschi, A. de, and Leachman, R. D.: Clinical and Angiographic Diagnosis of the Parachute Mitral Valve, Acta Cardio!. (Brux.) 24: 101, 1969. MaIm, J. R., Bowman, F. 0., Jesse, M. J., and Blumenthal, S.: Open Heart Surgery in the Infant, Am. J. Surg. 119: 613, 1970. Terzaki, A. K., Leachman, R. D., KhaIil, A. M., Hailman, G. L., and Cooley, D. A.: Successful Surgical Treatment for the Parachute Mitral Valve Complex, J. Thorac. Cardiovasc. Surg, 56: 1, 1968. O'Brien, J. R.: Effect of Salicylates on Blood Platelets, Lancet 1: 779, 1968. Emmons, P. R., Harrison, M. J. G., and Honour, A. J.: Effect of Dipyridamole on Human PlatIet Behaviour, Lancet 2: 603, 1965. Manubens, R., Krovetz, L. J., and Adams, P.: Supravalvular Stenosing Ring of the Left Atrium, Am. Heart J. 60: 286, 1960. El Sayed, H., Cleland, V. P., BentaIl, H. H., Melrose, D. G., Bishop, M. B., and Morgan, J.: Corrected Transposition of the Great Arterial Trunks: Surgical Treatment of the Associated Defects, J. THORAC. CARDIOVASC. SURG. 44: 443, 1962. Stretton, T. B., and Fentem, P. H.: Stenosis of the Left Atrioventricular Canal, Br. Heart J. 24: 237, 1962. Lynch, M. F., Ryan, N. J., and Williams, G. R.: Preoperative Diagnosis and Surgical Correction of Supravalvular Mitral Stenosis and Ventricular Septal Defect, Circulation 25: 854, 1962. Cassano, G. B.: Congenital Annular Stenosis of the Left Atrioventricular Canal, So-Cailed Supravalvular Mitral Stenosis, Am. J. Cardio!. 13: 708, 1964. Sancher Cascos, A., Rabago, P., Sokolowski, M., and Varela de Seijas, J. R.: Subvalvular Congenital Mitral Stenosis, Br. Heart J. 28: 808, 1966. Bett, J. H. N., and Stovin, P. G. I.: Parachute Deformity of the Mitral Valve, Thorax 24: 362, 1969. Easthope, R. N., Tawes, R. L., BonhamCarter, R. E., Aberdeen, E., and Waterstone, D. J.: Congenital Mitral Valve Disease Associated With Coarctation of the Aorta. A Report of 39 Cases, Am. Heart 1. 77: 743, 1969.