from the sinus of Valsalva above the right coronary ostium,passing behind the right ventricular outflow tract, through the ventricular septum, and entering the left.
Aortico-Left Ventricular Tunnel: A Case Report and Review of the Literature R. Llorens, M.D., R. Arcas, M.D., J. Herreros, M.D., A. De la Fuente, M.D., C. Barriuso, M.D.,J.A. CasilHas, M.D., and A. Enriquez, M.D. A 5-year-old child was operated on for aortico-left ventricular tunnel (ALVT). Postoperative cardiac catheterization revealed obliteration ofthe aortic end of the tunnel, normalization of systemic pressure and mild residual aortic valvular insufficiency. A review of the literature carefully considers the anatomical and clinical findings from previous reports involving 27 other patients, along with suggestions for appropriate surgical management of ALVT.
AN ABNORMAL communication between the aorta and the left ventricle in an adult was first reported by Hart' in 1902. He described a delayed rupture of a congenital aneurysm of the right sinus of Valsalva into the left ventricle. In 1961, Edwards2 recorded the case of an 18-month-old child with a saccular aneurysm of the ascending aorta communicating with the left ventricle. Levy and his associates3 first reported the entity of the aortico-left ventricular tunnel (ALVT) in three patients. It was described as an abnormal communication originating from the sinus of Valsalva above the right coronary ostium, passing behind the right ventricular outflow tract, through the ventricular septum, and entering the left ventricle below the right aortic cusp. Severe aortic regurgitation is well tolerated in the young, and with the current uncertainty about the long-term function of any valve prosthesis, care should be taken to avoid premature aortic valve replacement in a child or adolescent. How-
ever, the ALVT may be corrected without replacement of the aortic valve if surgery is performed before the valve cusps and annulus have become distorted.4 It is, therefore, important to distinguish between patients with a tunnel and those with primary valvular regurgitation to determine an appropriate method of treatment. Since 1963, when Levy3 described the entity in three patients, 25 additional patients have been reported. Of the 28 patients, seven nonsurgical patients and four surgical patients have died. The rarity of this malformation, the interesting clinical presentation, and the associated abnormalities prompted us to report this additional case and to review the literature.
Case Report A 5-year-old boy was referred for cardiac evaluation of a heart murmur that had been discovered at the age of 7 months. The patient was born after a normal gesta-
From the Service of Thoracic and Cardiovascular Surgery, University Clinic, University of Navarra, Pamplona,
Spain. Addressfor reprints: Rafael Llorens, M.D., Departamento de Cardiovascular, Clinica Universitaria, P'w XII, sln, Pamplona, Spain.
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tion period without complications, and there was no drug ingestion by the mother. He did not suffer respiratory infections or postnatal cyanosis. Development was normal with no symptoms that were apparent. On physical examination, the patient was a healthy-looking child, with a height of 106 cm, and a weight of 16 kg. The peripheral arterial pulses were bounding, and his blood pressure was 90/40 mm Hg. A systolic thrill was palpable over the precordial area. A Grade 2/4 continuous murmur was heard maximally at the left parasternal border; the systolic component was preceded by a click. There were no signs of congestive heart failure. A chest roentgenogram revealed Grade 3/4 cardiomegaly with enlargement of the left ventricle and ascending aorta. The pulmonary vasculature was normal (Fig. 1). The electrocardiogram showed a sinus rhythm, a QRS axis of -30°, and evidence of left ventricular hypertrophy with ST-T changes. Cardiac catheterization showed normal right ventricular and pulmonary pressures with no gradient between them (Table I). The pressures in the left ventricle and aorta were 120/0-10 mm Hg and 90/40 mm Hg, respectively. A retrograde aortogram (Fig. 2) showed massive reflux of contrast material into the left ventricle. On the lateral view, a tunnel into the left ventricle could not be seen. Although diagnosis was believed to be congenital aortic insufficiency, ALVT could not be ruled out in this study. At operation, the heart appeared to be normal except for moderate enlargement of the left ventricle and aneurysmal dilatation of the ascending aorta, arising from the right coronary sinus of Valsalva (Fig. 3). Upon opening the ascending aorta, the aortic valve was tricuspid and appeared to be normal. Immediately above the commissure, between the right and left coronary cusps, was a muscular orifice 9 mm long (Fig. 4). This opening gave an entrance to a tunnel-like communication wall that bypassed the aortic valve. It ran through the anterior cardiac wall and ventricular septum behind the right ventricular infundi-
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Fig. 1 Posteroanterior roentgenogram of chest shows left ventricular and ascending aorta enlargement.
Fig. 2 Retrograde aortogram shows a large left ventricular cavity, dilated ascending aorta, and a massive regurgitation of contrast material into the left ventricle.
Fig. 3 Intraoperative view: Aneurysm of ascending aorta, arising from the right coronary sinus.
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Fig. 4 After transecting the ascending aorta, inspection of the aortic valve and the tunnel shows the orifice of tunnel (T) and the aortic valve (AV) as tricuspid and slightly thickened.
bulum, ending in the left ventricle of the superior and anterior part of the ventricular septum,just below the right aortic leaflet. The operative procedure was performed with extracorporeal circulation, in normothermia, by using a bubble oxygenator. A transverse aortotomy was done and the aortic opening of the tunnel was closed with mattress sutures buttressed with Teflon pledgets (Fig. 5). The postoperative course was uneventful, and the patient was discharged on the tenth postoperative day. During follow-up at the end of 8 weeks, a soft aortic regurgitant Grade 1/4 murmur was heard, and a repeat cardiac catheterization was done. Right and left cardiac pressures and saturations were normal (Table I). The aortogram (Fig. 6) showed minimal aortic valve regurgitation. Discussion
Fig. 5 Closing of the aortic opening of the tunnel with mattress sutures buttressed with Teflon pledgets.
Fig. 6 Postoperative retrograde aortogram, left anterior oblique projection. Injection into ascending aorta demonstrates minimal aortic valve regurgitation.
Texas Heart Institute Journal
Aortico-left ventricular tunnel is a rare congenital anomaly, perhaps much rarer than congenital aortic regurgitation and congenital aneurysm of the sinus of Valsalva. In Levine's study of 600 patients with aortic regurgitation,5 only two cases were considered congenital. Before 1961, 90 cases of congenital aneurysm of the sinus of Valsalva were reported,6 but only 27 cases of aortico-left ventricular tunnel (ALVT) have been described. From an anatomical point of view, this entity is characterized by a tunnel-shaped connection between the aortic root and the left ventricle. The aortic origin is located just above the right aortic sinus of Valsalva and does not have any anatomical relationship to the right coronary ostium. The normal nature of the right aortic cusp and the right coronary artery rules out the possibility of this malformation's being a ruptured aortic sinus aneurysm or a coronary artery fistula.7 Morphologically, it is possible to distinguish two different portions of this tunnel: an aortic part, sometimes aneurysmatic, and a second intracardiac portion extend-
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ing from the right anterior aspect of the aortic root to the left ventricle. This second intracardiac portion, which runs through the interventricular septum in a dorsal situation to the right ventricular infundibulum, could explain the compression found intermittently.3'4'8'9 The exit of the tunnel in the left ventricle is located in the superior part of the ventricular septum just below the right and left aortic cusps. The clinical findings discussed here are based on our own case and 27 others described in the literature. More males than females were reported, with a ratio of 19 to 8, although in one case, the sex was not reported. Clinically, all the patients had a characteristic to-and-fro murmur, which was heard during the first week of life in 16 patients; in another 10 patients, it was heard between 2 months and 2 years of age. The clinical history was not available in one patient.2 Ejection clicks, although rare, may have been present. Congestive heart failure developed frequently, occurring in 11 patients within the first year of life. Only five patients (including ours) were described as being completely asymptomatic at the time of surgery. The electrocardiogram was described in 23 of the 28 patients. Twenty-two patients had left ventricular hypertrophy; two of them also had right ventricular hypertrophy. Only one had a normal electrocardiogram at the time of this initial presentation.'0 Echocardiographic examination in one patient showed a markedly dilated left ventricle (diameter: 27.3 mm at 3 months of age), with good ventricular contractility."I There was a fine high-frequency fluttering of the anterior mitral valve leaflet on diastole, suggesting aortic insufficiency. Despite multiple scans from the aorta to the ventricle, no structural abnormalities were noted. 12 In almost all cases, the chest X-ray films were characteristic of ALVT, showing a wide mediastinum that resulted from dilatation of the ascending aorta and cardiomegaly, with left ventricular configuration.
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Aortic aneurysm was found in all patients. A characteristic anterior indentation of the esophagus was described.'3 The diagnosis of a tunnel should be considered in any infant or young child with symptoms of gross aortic regurgitation. The diagnosis of ALVT is more likely when a loud murmur is noted in the first few months of life. A diastolic murmur louder than the systolic murmur and the presence of a diastolic thrill with maximum intensity at the left sternal border are additional symptoms suggestive of this diagnosis. A loud aortic valve closure is evidence of good cusp tissue.14 Routine chest radiography shows not only remarkable dilatation of the ascending aorta, which is seen in other forms of aortic regurgitation, but also a disproportionate dilatation of the right aortic sinus, which is occasionally visible on chest films. The dilatation of the ascending aorta may be present in the neonate and has been confirmed at autopsy.'5 The differential diagnosis of ALVT includes lesions in which there is an abnormal runoff from the aorta associated with murmurs in both the systolic and diastolic phases in conditions such as (1) ruptured congenital aortic sinus aneurysm, (2) ventricular septal defect with aortic insufficiency, (3) fistulas involving the coronary arteries, and (4) tetralogy of Fallot with absent pulmonary valve.'6 Right ventricular hypertrophy, normal pulse pressure, and absence of dilatation of the ascending aorta should differentiate the condition. The distinction between rupture of a congenital aneurysm of a sinus of Valsalva and ALVT rests on the premise that the rupture is an acquired complication, rare in neonates, that seldom communicates with the left
ventricle.6"7 Among the 28 patients, 23 underwent cardiac catheterization. The diagnosis of ALVT was based upon catheterization data in 12 patients. In the other 1 1, the diagnosis was not clear until operation or autopsy. In hemodynamic observations, five patients34'8"14 had evidence of aortic stenosis, and five3'4'8'9 had a gradient across the right
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ventricular outflow tract. The aortic valve was abnormal in 35% of the reported cases: Three patients had a bicuspid aortic valve3'4'9; six had a thickened tricuspid aortic valve9,10,13,14,18,19,26; and one had a dome-shaped tricuspid aortic valve, evident by angiography during systole. Associated anomalies were reported in four patients: one with pulmonic stenosis,3 one with patent ductus arteriosus and possibly pulmonic stenosis,8 one with patent ductus arteriosus and a patent foramen ovale,20 and one with an absent right coronary artery. 14 In her patients, Sommerville'4 reported an anticlockwise rotation of the aortic valve when viewed from above, so that the right coronary sinus was directed anteriorly and to the left. This is similar to the appearance of the aortic root in patients with ventricular septal defect2l and aortic regurgitation, and suggests a possible common developmental origin. Aneurysmal dilatation of the aortic root was found in all patients, and could compress the left coronary artery.2 Thoracic angiography is diagnostic20 if (1) a round double-density shadow is visualized above the aortic root in the region of the pulmonary trunk; (2) there is immediate reflux of contrast material into the left ventricle; and (3) there is absence of right heart filling. In our patient there was no visualized double round shadow because the aortogram was taken from a left anterior oblique view. Many different hypotheses about the structure and pathogenesis of this malformation have been proposed: 1. Levy and coworkers3 reported that elastic fibers of the media of the aorta were present in the tunnel wall up to its passage through the ventricular septum. On the tunnel wall, there was a resemblance of a sinusoid consisting of connective tissue, partly cellular and partly hyalinized. This finding suggested the possibility that the tunnel was an anomalous coronary artery ending the left ventricle through a myocardial sinusoid.
Texas Heart Institute Joural
2. Morgan and Mazur'3 believed that the pathogenesis of this malformation was due to the existence of an attenuated area in the aortic annulus, allowing a communication between the aorta and the left ventricle. The eddies resulting from a turbulent circulation of blood through this passage would be responsible later for the formation of an aneurysmatic tunnel. 3. Cooley and colleagues8 also observed the presence of elastic media in the tunnel. A large amount of acid mucopolysacchride contained in cyst-like spaces within the elastic media also was found; this led to the interesting hypothesis that medial cystic necrosis was the pathogenesis of the tunnel. 4. Roberts and Morrow4 found that the external wall of the tunnel consisted chiefly of collagen tissue containing only occasional fibers. Thus, they concluded that the structure of the tunnel wall was rather different from that of a blood vessel. 5. Bove and Schwartz9 proposed that this malformation was due to the existence of a dense fibrotic ridge across the superior margin of the right aortic sinus of Valsalva. The turbulence produced by this ridge might have led to a localized aneurysmal dilatation of the aortic root, rupturing posteriorly into the left ventricle. 6. Bharati,22 in an aortico-right ventricular tunnel, found an abnormal supravalvular ridge related to the right sinus of Valsalva. He postulated that the abnormal formation of the supravalvular ridge led to the weakness of the aorta above the ridge. This produced an aneurysmal dilatation of the primitive aorta, which secondarily made a connection to the left or right ventricle. 7. Spooner" speculated that a sinus of Valsalva aneurysm occurring early in utero could develop a communication with the myocardial sinusoids and result in a sinus of Valsalva aneurysm from which a tunnel into the left ventricle would arise.
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8. Shin-Sung and colleagues'9 believed that the tunnel was an anomalous coronary artery, although it contained purely elastic media without the cohesive muscular coat that one would expect to find in a coronary artery. 9. Soulie23 believed that the tunnel was either an acquired lesion with a dissecting aneurysm of the dystrophic aorta, opening into the left ventricle, or a congenital lesion with an anomalous coronary artery similar to a sinus of Valsalva, with embryological origin. At present, there is insufficient evidence to explain the pathogenesis of aorto-left ventricular tunnel (ALVT). Of the 28 patients reviewed, 21 had surgical correction. Early surgical deaths occurred in three cases. In two cases, death was attributed to associated valvular aortic stenosis.3'8 Postoperative infection was ruled as the cause of death in one case.7 Among the 18 survivors, at least 12 had signs of valvular aortic regurgitation postoperatively, and one had a fatal outcome despite repeated surgical intervention.'4 Only three patients were reported to have a competent aortic valve.""4'24 In some cases, information on this point was lacking.3'9 In five patients,'4'24'25 including our own case, postoperative aortic regurgitation was reinvestigated by catheterization and angiographic studies. This postoperative aortic insufficiency has been attributed in part to the prominent dilatation of the aortic root. 14 Another cause of aortic insufficiency mentioned is the valvular changes secondary to turbulence caused by flow through the tunnel. Also, it has been pointed out that when the tunnel passes close to the aortic valve, surgical obliteration may result in distortion of aortic valve orientation, with consequent incompetence of the valve. This may be avoided by closing the aortic opening of the tunnel with a Dacron patch.24'27 It should be mentioned that, in some cases, there is a congenital deformity of the aortic valve.'9 At this time, it is not possible to identify which of the previously mentioned factors 174
is responsible for the demonstrated postoperative aortic insufficiency; in a given case, multiple causes may apply.28 The consensus among authors is that the tunnel should be closed when the patient is very young. This might prevent valvular deformity,4"14 and, therefore) the need for future aortic valve replacement. The patient with ALVT is subject to the rapid onset of heart failure and sudden death.9 Sommerville and associatesl4 have proposed the age of 5 years as the ideal time for surgery.
References 1. Hart K. Uber das aneurysma des rechten Sinus Valsalvae der aorta nud seine beziehungen zum oberen ventrikelseptum. Arch Pathol Anat 1905;
182:167. 2. EdwardsJE. Atlas ofAcquired Diseases ofthe Heart and Great Vessels, Volume3. Philadelphia, WB Saunders, 1961; p 1142. 3. Levy MJ, Lillehei CW, Anderson RC, Amplatz K, Edwards JE. Aortico-left venticular tunnel. Circulation 1963; 27:841. 4. Roberts WC, Morrow AG. Aortico-left ventricular tunnel. A case of massive aortic regurgitation and intracardiac aneurysm. Am J Med 1965; 39:662. 5. Levine SA, Harvey PW. Congenital aortic insufficiency. In Clinical Auscultation ofthe Heart. Philadelphia, WB Saunders, 1959; p 453. 6. Sakakibara S, Konno S. Congenital aneurysm of the sinus of Valsalva, anatomy and classification. Am HeartJ 1962; 63:405. 7. Perez-Martinez V, Quero M, Castro C, Moreno F, Brito AM, Merino G. Aortico-left ventricular tunnel. Am HeartJ 1973; 85:237. 8. Cooley RN, Hari-is LC, Rodin AE. Abnormal communication between the aorta and left ventricle: Aortico-left ventricular tunnel. Circulation 1965; 31:564. 9. Bove KE, Schwartz DC. Aortico-left ventricular tunnel: A new concept. Am J Cardiol 1967; 19:696. 10. Bernhard WF, Plauth W, Fyler D. Unusual abnormalities of the aortic root or valve necessitating surgical correction in early childhood. N Engl J Med 1970; 282:68. 11. Spooner EW, Dunn JM, Behrendt DM. Aorticoleft ventricular tunnel and sinus of Valsalva aneurysm. J Thorac Cardiovasc Surg 1978; 75:232. 12. Rothbaum DA, Dillon JC, Chaug S, Feigenbaum H. Echocardiographic manifestations of right sinus of Valsalva aneurysm. Circulation 1974; 49:768. 13. Morgan RI, Mazur JH. Congenital aneurysm of aortic root with fistula to left ventricle: A case report with autopsy findings. Circulation 1963; 28:589.
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14. Sommerville J, English T, Ross DN. Aortico-left ventricular tunnel: Clinical features and surgical management. Br Heart J 1974:36:321. 15. Morton P,JurtaghJG, O'Hara MD. Aneurysm of interventricular septum with aortic valve malformation in an infant. Br HeartJ 1969; 31:807. 16. Osman MZ, Meng CCL, Girdany BR. Congenital absence of the pulmonary valve: Report of eight cases with review of the literature. AJR 1969; 106:58. 17. Aniger LE, PatteJW. Rupture of a sinus of Valsalva in an infant. Am J Cardiol 1963; 10:547. 18. Mair DD, Fulton RE, McGoon DC. Successful surgical repair of aortico-left ventricular tunnel in an infant. Mayo Clin Proc 1975; 50:691. 19. Shin-Sung Ch, Leachman RD, Zerpa R, Augehni P, Lufschanowski R. Am HeartJ 1979; 98:87. 20. Fishbone G, Delenchtenberg N, Stannel HC. Aortico-left venticular tunnel. Radiology 1971; 98:579. 21. SommervilleJ, Brandao A, Ross DA. Aortic regurgitation with ventricular septal defect. Surgical
Texas Heart Institute Journal
management and clinical features. Circulation 1970; 41:317. 22. Bharati S, Lev M, Cassels DE. Aorto-right ventricular tunnel. Chest 1973; 63:198. 23. Soulie P, Caramanian M, PernotJM, Pauly-Laubry C. Communication ou tunnel aorto-ventriculaire gauche. Arch Mal Coeur 1966; 59:820. 24. Bjork VO, Eklof 0, Wallgren G, Zetterqvint P Successful surgical treatment of an aortico-left ventricular tunnel in a four-month-old infant. J Thorac Cardiovasc Surg 1979; 78:35. 25. Okorama EO, Perry LW, Scott LP, McClenathan JE. Aortico left ventricular tunnel. Clinical profile, diagnostic features, and surgical considerations. J Thorac Cardiovasc Surg 1976; 71:238. 26. Nichols GM, Lees MH, Henken DP, Sunderland CO, Starr A. Aortico-left ventricular tunnel. Chest 1976; 70:74. 27. Dubost CH, CacheraJP, Branchini B, Pedeferri G. Tunnel aorto-ventriculaire gauche. Reparation chirurgicale. Ann Chir Cardiovasc 1970; 9:157. 28. EdwardsJE. Aortico-left ventricular tunnel. Editorials: Chest 1976; 70:5.
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