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Stenotic Semilunar Valve in Persistent Truncus Arteriosus* Marion K. Ledbetter, M.D.; Rajendra Jack L. Titus, M.D., and Jesse Tandon, E. Edwards, M.D.; M.D., F.C.C.P. The clinical, hemodynamic, and pathologic findings in truncus arteriosus arose exclusively from the right ven- two newborn infants with persistent truncus arteriosus tricle and was almost exclusively stenotic. A ventricular and stenosis of the truncal valve are described. In one septal defect was the only outlet for the left ventricle. In case the anatomic features of the basic condition were this case, mitral stenosis was also present and associated classic, with a dysplastic semilunar valve which was main- with a left-to-right shunt at the atrial level. ly stenotic and also incompetent, while in the other the W^ he valve of persistent truncus arteriosus is often CASE REPORTS r dysplastic and incompetent The clinical, hemodynamic, 1 but rarely stenotic. and pathologic find- ings of a stenotic truncal valve were first described in a case report by Burnell and associates in 1971 2 and again by Lee and associates in 1973. W e have 3 observed two examples of truncal valvular stenosis; our case 1 was similar to that of Burnell et al, z and case 2 had some findings like that of Lee et al. 3 The purpose of this report is to present the clinical, hemodynamic, and necropsy findings of these two cases. Both had been admitted shortly after birth (within a three-week period) to the intensive care nursery of St. Mary's Hospital, Madison, Wis. We could not find any common features in the gestational histories to indicate pathogenesis. However, case 1 had a strong family history of congenital heart disease. Following initial management of congestive failure, both babies were subjected to cardiac cathe- terization to establish the diagnosis. Thereafter, they were transferred Hospitals further and to the the Mayo consideration University Clinic, regarding of Minnesota respectively, the feasibility for of operation. " F r o m the Section of Pediatric Cardiology, St. Mary's Hospital Medical Center, Madison, W i s . ; the Departments of Pathology, United Hospitals-Miller Division, St. Paul, a n d the University of Minnesota, Minneapolis; and the Section of Pathologic Anatomy, Mayo Clinic, Rochester, Minn. This study was supported by Public Health Service research grant 5 R O l H L 0 5 6 9 4 and research training grant 5 T O l H L 0 5 5 7 0 from the National Heart and L u n g Institute. Manuscript received June 5 ; revision accepted August 4 . Reprint requests: Dr. Edwards. United Hospitals (Miller Division), 125 West College Avenue, St. Paul 55102 182 CASE 1 Clinical Features. T h e boy was the product of an uncomplicated 42-week gestation in a 27-year-old primigravida woman. Delivery was uncomplicated, and the infant's birth weight was 4 , 0 2 6 gm ( 8 lb, 14 o z ) . Resuscitative measures were not required, and the Apgar score was 9 at one minute. However, at 3 0 minutes the skin had become dusky; and tachycardia, tachypnea, and a loud continuous murmur were present. Cardiac consultation at 7 5 minutes revealed mild cyanosis of the lips while the infant breathed high concentrations of oxygen. T h e respiratory' rate was 70/min, with intercostal retractions. A coarse thrill was palpable at the apex and left axilla. Both heart sounds were loud. A grade 3/6 systolic murmur was followed by a single second sound. A loud high-pitched murmur persisted through diastole, was loudest at the cardiac base and third left interspace, and sounded more like a ductus arteriosus than aortic insufficiency. A loud diastolic flow murmur was heard at the apex. T h e brachial and femoral pulses were normal. T h e hepatic edge was palpated 3 cm below the right costal margin. An electrocardiogram on the day of hirth showed sinus rhythm with a rate of 1 5 0 beats per minute. T h e mean frontal-plane Q R S axis was + 9 0 . T h e tracing was within the normal range for the newborn. Thoracic roentgenograms showed a shift of the mediastinum and the heart to the left, with prominent pulmonary vascular markings. T h e cardiac size and the pulmonary congestion increased over the next three days. Administration of digoxin and ethacrynic acid was begun at 12 hours of a g e without appreciable response. Cardiac catheterization was performed at 2 0 hours of age. T h e catheter could b e advanced into the right pulmonary artery from the ascending aorta, suggesting the presence of truncus arteriosus. A withdrawal tracing from the right pulmonary artery to the truncus arteriosus and the right ventricle showed a stepwise increase in pressures ( T a b l e 1 ) . T h e left ventricle LEDBETTER ET AL Downloaded From: http://publications.chestnet.org/pdfaccess.ashx?url=/data/journals/chest/20976/ on 05/02/2017 CHEST, 6 9 : 2 , FEBRUARY, 1 9 7 6 T a b l e 1 — C a r d i a c Catheterization Data from Caseg 1 and Case 1 (Age, 2 0 hr) ((xygen Site Saturation ( % ) * * Superior vena eava Inferior vena eava Right atrium Left atrium R i g h t ventricle 68 65 65 93 64 Left ventricle Aorta Right pulmonary artery 83 69 Case 2 (Age. 6 days) Pressure (mm H g ) f , A S/D 7/1 9/-1 126/-9 (ed = 10) 130/-5 (ed = 10) 72/32 51/29 *A11 venous pressures were " a " waves. * ' S a t u r a t i o n s were obtained while breathing air. ^ Mean 8/3 6/2 2* Oxygen Saturation ( % ) * * Pressure (mm H g ) f SI) Mean 4 3 2 4 60 69 78 96 79 16/4 15/2 15/2 19/7 134/-6J (ed = 18) 8 7 7 13 47 91 58/38J 45 40 f S / D , Systolie/diastolic; and ed, end-diastolic. ^Simultaneous pressures. was catheterized from the right ventricle via a ventricular septal defect. Oxygen saturations revealed evidence of bidirectional shunting of blood. O n the basis> of preferential streaming, there was a significant difference in the oxygen saturations of the blood between the right pulmonary artery and the aorta; the former was 6 9 percent and the latter 8 3 percent saturated. An aortogram ( F i g l a ) showed filling of both pulmonary arteries from the base of the arterial trunk, as well as a right aortic arch, confirming the diagnosis of persistent truncus arteriosus. T h e r e was regurgitation of moderate degree through the semilunar valve. A left ventriculogram ( F i g l b ) showed a jet of contrast medium through the truncal valve, confirming the stenosis indicated by withdrawal pressure tracings. T h e contrast medium cleared promptly from the heart, indicating that semilunar valvular insufficiency was not severe. Despite vigorous anticongestive measures, the infant died at six days of age. T h e family history was interesting in that the infant's father had tetralogy of Fallot with pulmonary atresia, a diagnosis which had been established by cardiac catheterization; also, a paternal aunt had a ventricular septal defect which had been repaired surgically. Pathologic Features. T h e cardiac and visceral configuration was that of situs solitus. T h e heart was moderately en- larged. Only one great vessel, measuring 12 mm in diameter, arose above the ventricles. T h e pulmonary trunk came off from the left side of this vessel, a situation seen in type 1 persistent truncus arteriosus. T h e pulmonary trunk divided immediately into the left and right pulmonary arteries with normal course and distribution ( F i g 2 ) . T h e truncal valve was bicuspid and dysplastic. Both of the thickened cusps showed further incomplete division, suggesting a quadricuspid valve. T h e diameter of the lumen through the valve was 6 mm ( F i g 3 ) . T h e first set of branches from the truncus arteriosus were the two coronary arteries. T h e y c a m e off behind the opposite, incompletely divided cusps anteriorly and posteriorly. T h e distribution of the artery arising anteriorly was like that of the right coronary artery, while that of the other was like the left coronary artery. T h e next branch from the truncus was the pulmonary trunk, 6 mm in diameter, which arose 5 mm above the truncal valve. T h e aortic arch was right-sided. T h e branching from the arch had a mirror-image distribution ( F i g 2 a ) . T h e ductus arteriosus was absent. T h e systemic and pulmonary venous returns were normal, and the coronary sinus opened normally into the right atrium. A 10 X 3 mm atrial septal defect resulting from a valvular incompetent foramen ovale was present at the fossa ovalis. T h e tricuspid and mitral F I G U R E 1 ( c a s e 1 ) . a (left). Catheter is in dilated truncus arteriosus. Right aortic arch is present. Large pulmonary arteries arise from base of common trunk, b. ( r i g h t ) . Injection during systole into base of left ventricle. Jet of contrast material streams through stenotic truncal valve. CHEST, 69: 2, FEBRUARY, 1976 PERSISTENT TRUNCUS ARTERIOSUS Downloaded From: http://publications.chestnet.org/pdfaccess.ashx?url=/data/journals/chest/20976/ on 05/02/2017 183 FIGUHE 2 ( c a s e 1 ) . a ( l e f t ) . Truncus arteriosus has been sectioned above truncal valve to display short pulmonary trunk from which, in turn, right ( R P ) and left ( L P ) pulmonary arteries arise. Aorta ( A o ) proceeds upward as right aortic arch which lies to right of trachea ( T r ) . b (right). Right ventricle ( R V ) and truncal valve. Immediately beneath valve is characteristic ventricular septal defect. ( D ) . CASE 2 valves were normal and led into hypertrophied and dilated right and left ventricles, respectively. T h e right ventricular wall measured 5 mm and the left ventricular wall 6 mm in thickness. T h e truncus arteriosus was the outlet for both ventricles. It overrode the ventricular septum, arising approximately two-thirds above the right and one-third above the left ventricle ( F i g 2 ) . T h e ventricular septal defect, 10 mm in diameter, was in the superior aspect of the septum and immediately below the origin of the truncus arteriosus. On the right ventricular aspect the poorly developed parietal limb of the crista supraventricularis separated the truncal valve from the tricuspid valve. Mitral-truncal valvular continuity was maintained. was heard at the cardiac apex. T h e second sound was split with a wide interval unchanged during the respiratory cycle. T h e liver projected 3 cm below the right costal margin. Brachial and femoral arterial pulses were equal and slightly bounding in contour. A roentgenogram of the thorax revealed cardiomegaly with a globular configuration of the heart and increased pulmonary vascular markings. T h e E C G showed a short P-R interval, negative delta waves in lead V ] , and wide Q R S complexes with a duration of 0.10 second, indicating the type B Wolfl-Parkinson-White syndrome. This pattern persisted unchanged. T h e infant was digitalized but remained lethargic, nursed pm)rly, and continued in a state of congestive failure. Cardiac catheterization at six days of age ( T a b l e 1 ) re- Clinical Features. T h e patient was a 3 , 1 7 5 gm ( 7 l b ) girl. T h e 42-week gestation of the 23-year-old gravida 2 mother was complicated only by cystitis during the sixtii month, for which sulfonamide compounds were administered. Resuscitation of the infant was not necessary. T h e Apgar score at one minute was 8 and at five minutes was 10. Slight duskiness of the skin and a grade 2/6 systolic murmur were noted at 3 0 minutes. A grade 4/6 systolic murmur and a diastolic murmur were noted on the third day after birth. On the fourth day of life, the infant was transferred to the intensive care nursery of St. Mary's Hospital Medical Center. Examination on admission at four days of age revealed edema involving the face and eyelids. T h e infant was mildly cyanotic and somnolent but was easily aroused. T h e breath sounds were clear with shallow excursions at 60/min. T h e cardiac rate was 155 beats per minute, and the sounds were accentuated. T h e first sound was followed by a grade 4/6 systolic murmur and thrill most intense at the fourth left interspace. T h e murmur was widely transmitted over the anterior wall of the thorax, and a middiastolic flow murmur 184 F I C U R E 3. Unopened truncal valve viewed from above. Valve is markedly dysplastic and stenotic (case 1 ) . LEDBETTER ET AL Downloaded From: http://publications.chestnet.org/pdfaccess.ashx?url=/data/journals/chest/20976/ on 05/02/2017 CHEST, 6 9 : 2, FEBRUARY, 1976 minimally regurgitant, with only a small amount of contrast medium entering the heart after the truncal injection. A left atriogram revealed a small left atrium with a large shunt into the dilated right atrium. A small left ventricle and the truncus arteriosus were visualized following flow through the mitral valve. T h e diagnosis after cardiac catheterization was type 1 or 2 truncus arteriosus with atrial and ventricular septal defects and truncal valvular stenosis. T h e infant remained in severe congestive cardiac failure; therapy with digitalis and diuretics was continued. T h e cardiac size increased progressively, and left pleural effusion developed. W h e n quiet and breathing air, the infant showed nearly normal cutaneous color, but mild cyanosis occurred when she cried. T h e infant died at 24 days of age. Pathologic Features. T h e essential pathologic features were as follows. Arising from the right ventricle was a single arterial vessel. This divided into a short pulmonary trunk, from which the right and left pulmonary arteries and the aorta arose. T h e aortic arch was left-sided. T h e truncal valve was quadrieuspid and stenotic. T h e mitral valve was hypoplastic and stenotic. T h e left ventricular chamber was also hypoplastic, and its only outlet was a narrow muscular-type ventricular septal defect. T h u s , there was no mitral-truncal valvular continuity. T h e chambers of the right atrium and ventricle were enlarged, and the valve of the foramen ovale was herniated toward the right atrium. F I G U R E 4. Systolic pressure of right ventricle measured twice corresponding systolic pressure of truncus arteriosus. High pressure flush (arrow) indicates that truncal pulse recorded through No. 4 French catheter is minimally damped. E l e c t r o cardiogram reveals delta waves of preventricular excitation (case 2 ) . vealed elevated systemic venous pressures and a left-to-right shunt at the atrial level. T h e right ventricular systolic pressure measured more than twice the aortic systolic pressure ( F i g 4 ) . T h e left ventricle could not he catheterized. Selective cineangiograms revealed large pulmonary arteries which originated from the base of the truncus arteriosus above a narrow root ( F i g 5 ) . T h e truncal valve was narrowed and DISCUSSION A diagnosis of persistent truncus arteriosus requires that the systemic, pulmonary, and coronary circulations arise from a common trunk which emerges from the heart. The truncus arteriosus usually arises more from the right ventricle than from the left ventricle. Origin from only the right ventricle is a rare form of the anomaly previously reported by Lampertico (case 4 3 ) , but without the semilunar valvular stenosis. Dysplasia of the semilunar valves is common in truncus arteriosus. 4 1 F I G U R E 5. (case 2 ) . a ( l e f t ) . Catheter entered truncus arteriosus retrogradely from femoral artery and left aortic arch. Dilated pulmonary arteries arise from common vessel, b (right). Dilated and heavily trabeculated right ventricle gives origin to dilated common trunk above narrowed root. Stenotic valve domes into vessel. CHEST, 6 9 : 2, FEBRUARY, 1976 PERSISTENT TRUNCUS ARTERIOSUS Downloaded From: http://publications.chestnet.org/pdfaccess.ashx?url=/data/journals/chest/20976/ on 05/02/2017 185 Gelband and associates presented autopsy data from 12 babies less than six months of age, seven of whom had deformed and incompetent truncal valves. In these latter seven, refractory cardiac failure had been present. Van Praagh and Van Praagh reported the pathologic findings in one case with probable truncal valvular stenosis. Victorica and associates reported catheterization data on two patients with significant ventricular-truncal valvular gradients, but without pathologic data. Victorica et al presented phonocardiographic evidence that the second heart sound may be split (as in our case 2) when only one semilunar valve is present. Victorica (personal communication) described the autopsy of another newborn infant with a quadricuspid stenotic truncal valve. Two of the cusps were completely fused. Tandon and associates reported systolic ejection murmurs in eight of 19 cases of persistent truncus arteriosus, but catheterization data revealed no important pressure gradients between either ventricle, on one hand, and the truncus arteriosus, on the other. As mentioned before, the hemodynamic and pathologic features of our case 1 were similar to the case of truncal valvular stenosis reported by Burnell and associates, with the exceptions that their infant had diminished peripheral pulses, whereas ours did not; and their infant had a left aortic arch, and our case 1 had a right arch. Except for the stenotic semilunar valves, the case of Burnell et al and our case 1 may be considered classic examples of persistent truncus arteriosus in that the common trunk overrode a large ventricular septal defect, and truncal-mitral valvular fibrous continuity was preserved. Also, as previously mentioned, the hemodynamics and cardiac anatomy of our case 2 had similarities to the case of Lee and associates. The persistent truncus arose only from the right ventricle; therefore, egress from the left ventricle was only through the ventricular septal defect into the right ventricle. Venous pressure and right ventricular systolic and end-diastolic pressures were severelyelevated. The main differences were that our case 2 had a stenotic mitral valve, a small left ventricle, and a narrow ventricular septal defect, whereas the case of Lee et aP had a large ventricular septal defect and a dilated left ventricle. Becker and associates performed gross and histologic studies on the semilunar valves from 14 cases of truncus arteriosus. All had abnormal deposits of mucoid connective tissue on the valve cusps, with progression to gross nodularity in nine. The process had extended onto the commis5 6 7 7 8 2 2 3 sures in four cases. Though none of these valves appeared stenotic, these workers postulated that greater degrees of this dysplastic process might cause stenosis. When the semilunar valve is severely dysplastic in truncus arteriosus, insufficiency is nearly always the only abnormality of hemodynamic importance. Congestive heart failure usually causes the death of these infants by two months of age. 5 Progression to stenosis can occur, and stenosis was the dominant lesion involving the valves of both babies in our report. Case i, in whom there was associated insufficiency of the valve, had normal peripheral pulses. The pulses of case 2 were bounding in contour, although the degree of semilunar valvular incompetence was barely appreciable by aortography. A stenotic semilunar valve may be incompetent to the extent that it cannot close in diastole. A severely stenotic valve may be minimally incompetent, since the orifice is small. The character of peripheral pulses is not entirely dependent on the anatomy of the semilunar valve. In truncus arteriosus, there is free runoff of the blood into the pulmonary arteries, as occurs in the patent ductus arteriosus, and the pulses may have a wide contour even when the truncus valve is competent. Conversely, congestive cardiac failure associated with decreased systemic perfusion causes lowering of the blood pressure and diminishes pulses. The rapid onset of congestive cardiac failure in our case 1 and the short fulminating course of both patients despite decongestive measures attest to the clinical importance of these truncal valvular lesions. The relatively high oxygen consumption of postnatal life may have contributed to the development of congestive cardiac failure shortly after birth rather than prenatally. The volume overload of a large pulmonary flow was added at birth to the prenatally sustained pressure overload. We considered surgical palliation of these two infants by valvotomy and banding of the pulmonary arteries. However, it seemed unlikely that integrity of the truncal valve would have been obtained. With the origin of the truncus from the right ventricle in case 2, the stenotic mitral valve and the narrow ventricular septal defect would have obviated a satisfactory operative result. REFERENCES 1 186 1 Becker A E , Becker MJ, Edwards J E : Pathology of semilunar valve in persistent truncus arteriosus. J Thorac Cardiovasc Surg 6 2 : 1 6 - 2 6 , 1971 2 Burnell RH, McEnery G, Miller G A H : Truncal valve stenosis. Br Heart J 3 3 : 4 2 3 - 4 2 4 , 1971 3 Lee M J , Bellon E M , Liebnian J , et al: Truncal valve steno- LEDBETTER ET AL Downloaded From: http://publications.chestnet.org/pdfaccess.ashx?url=/data/journals/chest/20976/ on 05/02/2017 CHEST, 69: 2, FEBRUARY, 1 9 7 6 sis. Am Heart J 8 5 : 3 9 7 - 4 0 0 , 1 9 7 3 4 Lampertico P : Persistent truncus arteriosus communis: Review of the literature and presentation of 4 9 cases of true truncus arteriosus and 18 examples of related conditions. Folia Hered Pathol 1 4 ( s u p p l 4 ) : 1-134, 1 9 6 4 5 Gelband H, Van Meter S, Gersony W M : Truncal valve abnormalities in infants with persistent truncus arteriosus: A clinicopathological study. Circulation 4 5 : 3 9 7 - 4 0 3 , 1972 6 Van Praagh R, Van Praagh S: T h e anatomy of common aorticopulmonary trunk (truncus arteriosus communis) and its embryologic complications: A study of 57 necropsy cases. Am J Cardiol 1 6 : 4 0 6 - 4 2 5 , 1 9 6 5 7 Victorica B E , Krovetz L J , Elliott L P , et a l : Persistent truncus arteriosus in infancy: A study of 14 cases. Am Heart J 7 7 : 1 3 - 2 5 , 1 9 6 9 8 Tandon R, Hauck A J , Nadas A S : Persistent truncus arteriosus; A clinical, hemodynamic, and autopsy study of nineteen cases. Circulation 2 8 : 1 0 5 0 - 1 0 6 0 , 1 9 6 3 The Larynx F e w o r a t o r s of f a m e , p r e a c h e r s of g r e a t p o p u l a r i t y , brilliant a c t o r s a n d a c t r e s s e s of t h e t h e a t e r , o r o u t s t a n d i n g vocal artists of c o n c e r t s halls a n d o p e r a h o u s e s h a v e b e e n a w a r e or a p p r e c i a t i v e of t h e i n t r i c a t e f u n c t i o n a l m a r v e l s of t h e i r v o c a l a p p a r a t u s . T h r o u g h e o n s , p h o n a tion has b e c o m e a u n i v e r s a l m a n n e r of h u m a n c o m m u n i c a t i o n . I t is b r o u g h t a b o u t b y t h e r e l e a s e o f puffs o f air ( a i r p u l s e s ) t h r o u g h t h e glottis. T h e n u m b e r o f these puffs, d e t e r m i n e d by t h e resilience, tension and v i b r a t i o n of t h e v o c a l c o r d s , g o v e r n s t h e p i t c h o f t h e v o i c e w h e n v o c a l i z i n g . It w a s P y t h a g o r a s (540-500 B C ) , the Greek philosopher and mathematician, who first a s c e r t a i n e d t h a t t h e p i t c h o f s o u n d is p r e d i c a t e d o n t h e l e n g t h of t h e v i b r a t i n g c o r d ; also, h e w a s t h e disc o v e r e r of t h e m e c h a n i s m of t o n a l h a r m o n y . I n c o n v e r s a tional s p e e c h t h e f r e q u e n c y of v i b r a t i o n s of t h e v o c a l c o r d s varies f r o m 8 0 c y c l e s p e r s e c o n d in m e n to 4 0 0 c y c l e s p e r s e c o n d in w o m e n . T h r o u g h o u t r e c o r d e d h i s tory s i n g i n g h a s d e v e l o p e d i n t o a u b i q u i t o u s m e a n s for e x p r e s s i n g p e r s o n a l j o y or s o r r o w , r e l i g i o u s d e v o t i o n , patriotic dedication, melancholic yearning, and boisterous m a r t i a l c o u r a g e . T h e c l i m a x o f artistic s i n g i n g is best exemplified by the phonatory calisthenics of colora t u r a s o p r a n o s , b y v o c a l e x h i b i t i o n in m u s i c d r a m a s , a n d by the b e l c a n t o v i r t u o s i t y of s i n g e r s in roles i d e n t i f i e d with m e l o d i o u s , l y r i c a l , r o m a n t i c a r i a s . T h e s t r u c t u r e o f t h e l a r y n x is b a s e d on n i n e c a r t i l a g e s ( t h r e e s i n g l e and three p a i r e d ) : t h e epiglottis, thyroid, cricoid, aryte n o i d s , c o r n i c u l a t e s of S a n t o r i n i a n d t h e c u n e i f o r m s o f W r i s b e r g . T h e v o c a l c o r d s a r e r e a d i l y v i s u a l i z e d b y ind i r e c t l a r y n g o s c o p y . T h e l a t t e r w a s i n v e n t e d b y a singing t e a c h e r M a n u e l G a r c i a ( 1 8 0 5 - 1 9 0 6 ) , b o m in M a d r i d , t e a c h i n g in L o n d o n a n d P a r i s . T h e i n t r i n s i c l a r y n g e a l muscles modulate phonatory changes of the vocal cords. T h e f u n c t i o n a r y role o f t h e s e m u s c l e s is well s u m m a r i z e d in o n e of t h e m e d i c a l c l a s s i c ( G r a y , H : A n a t o m y o f t h e Human Body, 29th ed, American ed b y Goss, C M P h i l a d e l p h i a , L e a and F e b i g e r , 1 9 7 4 ) . T h e p o s t e r i o r cricoarytenoids separate the vocal cords and thus open t h e glottis. T h e l a t t e r is c l o s e d b y t h e l a t e r a l c r i c o a r y t - CHEST, 69: 2, FEBRUARY, 1 9 7 6 e n o i d s . T h e u n p a i r e d a r y t e n o i d c l o s e s t h e glottis, e s p e c i a l l y a t its b a c k p a r t . T h e c r i c o t h y r o i d s t i g h t e n a n d e l o n g a t e t h e v o c a l c o r d s a n d c l o s e t h e glottis. T h e m a i n u s e of t h e t h y r o a r y t e n o i d s is to s h o r t e n a n d relax t h e v o c a l c o r d s . " T h e i r l a t e r a l p o r t i o n s n a r r o w t h e riga glottidis by bringing t h e vocal cords together. Certain m i n u t e fibers of t h e v o c a l i s division, d e s i g n a t e d as a r y v o c a l i s m u s c l e s a r e c o n s i d e r e d b y S t r o n g ( ' 3 5 ) to b e c h i e f l y r e s p o n s i b l e f o r t h e c o n t r o l of p i t c h , t h r o u g h t h e i r a b i l i t y to r e g u l a t e t h e l e n g t h of t h e v i b r a t i n g p a r t of t h e v o c a l f o l d s . " I t is t r u l y a m a z i n g t o w i t n e s s t h e f a c i l i t y w i t h w h i c h t r a i n e d s i n g e r s a r e a b l e to p r o d u c e m e l l i f l u o u s , e n c h a n t i n g m e l o d i e s , or s o n o r o u s e x p r e s s i o n o f dramatic emotions b y maneuvering the laryngeal struct u r e s as if t o u c h i n g t h e k e y s o f a p i a n o or t h e strings of a Stradivarius, with virtuoso dexterity. Jackson, C a n d Jackson, C L (Diseases of the Nose, T h r o a t and E a r , 2 n d e d , P h i l a d e l p h i a , S a u n d e r s , J 9 5 9 ) offer t h e f o l l o w i n g p e r t i n e n t c o m m e n t s . " T h e t r a i n e d s o p r a n o , in producing high notes, unconsciously increases the t r a c h e a l a i r p r e s s u r e c o o r d i n a t e l y as s h e firms t h e c o r d a l e d g e s a n d s h o r t e n s t h e s u p r a g l o t t i c air c o l u m n b y r a i s i n g t h e larynx a n d d i a m e t r i c a l l y d i m i n i s h e s t h e oral a n d p h a r y n g e a l air c o l u m n b y f o r c i n g u p w a r d all tissues a t t a c h e d t o t h e h y o i d b o n e . T h e lips a r e t r a i n e d to b e kept separated widely. Additionally the trained soprano narrows the ventricle a n d p h a r y n x . " T h u s , transposition o f l i f e l e s s m u s i c a l n o t e s i n t o b e a u t i f u l s i n g i n g is t h e a d m i r a b l e r e s u l t of t h e i n t e r p l a y o f t h e c e n t r a l n e r v o u s system, t h e diaphragm, thoracic and relatively miniat u r e m u s c l e s of t h e l a r y n x . T h e v o i c e o f c o l o r a t u r a sop r a n o , L u c r e z i a A g u j a r i of 1 8 t h c e n t u r y I t a l y , r e a c h e d u p t o C in alt, ie a w h o l e o c t a v e a b o v e h i g h C , c o r r e s p o n d i n g to a v o c a l c o r d v i b r a t i o n o f 2 0 4 8 c p s as c o m p a r e d to 1 4 0 8 c p s o f t h e v o c a l c o r d s o f o t h e r sop r a n o s . W h a t a h e a v e n l y r e v e l a t i o n it m u s t h a v e b e e n to M o z a r t w h o h a d listened to a recital given b y L u c r e z i a A g u j a r i in P a r m a , I t a l y . Andrew L. Banyai, PERSISTENT TRUNCUS ARTERIOSUS Downloaded From: http://publications.chestnet.org/pdfaccess.ashx?url=/data/journals/chest/20976/ on 05/02/2017 M.D. 187