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Isolated Anomalous Right Ventricular Muscle Bundle in the Asymptomatic Adult
Isolated Anomalous Right Ventricular Muscle Bundle in the Asymptomatic ~ d u l t * K.L. Wandemtan, M.D.; M . Hirsch, M.D.; I. Ousyshcher, M.D.; and M . Cueron, M.D. Muscular obstruction to right ventricular outflow is IISUally at the infundibular level, but, less commonly, it can occur within the body of the ventricle due to an anom* lous muscle bundle. This lesion is almost always associated with a ventricular septal defect or other cardiac MOOS, and is usually discovered in infancy or childhood. TWO
asymptomatic adults with severe obstruction due to a right ventricular muscular band as an isolated lesion are presented. The lesion can be tentatively diagnosed on clinical grounds and confirmed by angiocardiography. The advisability of surgical correction in the asymptomatic aduit with such an isolated lesion is uncertain.
uscular obstruction to right ventricular outflow is not an uncommon finding when associated with other cardiac lesions. It is frequently seen in tetralogy of Fallot and in pulmonic stenosis with intact ventricular septum. It can also occur in cases of idiopathic hypertrophic cardiomyopaIn these cases the obstruction is due to hypertrophied muscle protruding from the infundibular walls. Less commonly, right ventricular outflow may be interfered with by an anomalous muscle bundle arising proximal to the infundibulurn and crossing the right ventricular c a ~ i t y .This ~ lesion is also, in the vast majority of cases, not an isolated one, almost always being associated with a ventricular septa1 defect or other anomalies. The purpose of this report is to present two asymptomatic adults with anomalous right ventricular muscle bundle in the absence of any detectable associated defects.
sternum., and., to a lesser extent. to the apex. The second heart sound was normal. The electrocardiogram showed a frontal axis of about +90°, an RS pattern in the chest leads with a notched R wave of 6 to 8 mm in V1,and peaked P waves, and the vectorcardiogram confirmed the diagnosis of right ventricular hypertrophy. On the chest roentgenogram, the heart was mildly enlarged and pulmonary vasculature a p peared normal. The findings on cardiac catheterization are given in Table 1. A systolic gradient of 130 mm Hg was found on pull-back from the infundibulum to the body of the right ventricle. Oxygen saturation determinations and dve dilution curves in the right heart cavities showed no evidence of a shunt in either direction. Right ventricular angiocardiography was performed (Fig 1 and 2 ) . An obliquely placed bandlike filling defect was seen, narrowing the entrance to the infundibulum. The
-
Table 1 4 a t h e t e r i d o n Finding.
CASE1 Pressure Ot Satumm Hg ration ?&
Location
CASE2 Pressure Ot Satumm Hg ration QJo
Superior vena cava Right atrium A 38-vear-old married woman. mother of two children. was examined because of a heart murmur discovered on routine examination several years previously. She was asymptomatic. On physical examination she was well developed and appeared healthy; there was no cyanosis. The arterial pulses were normal. Mildly prominent "A" waves were visible in the neck veins. The apex beat was not felt and there were no abnormal lifts. A systolic thrill was felt along the left lower sternal border. On auscultation, a long, harsh, ejection-type systolic murmur, grade 4/6, was heard-maximal at the left sternal border in the 3rd to 5th intercostal space; radiating upwards to the 2nd left intercostal space, to the right of the *From the Cardiac Laboratory and Deparhnent of Radiology, Soroka Medical Center, Beer-Sheva, Israel. Manuscript received August 26; revision accepted October 24. Reprint requests: Dr. Gueron, Negeo Central Hospital, Beer Sheoa, Israel
692 WANDERMAN ET A1
high mid low Right ventricle inflow tract apex outflow tract Pulmonary artery main right left Brachial artery ---
a =a wave
-
-
-
-
v = v wave
-
-
m =mean
CHEST, 67: 6, JUNE, 1975
FIGURE1. (Case 1). Right ventricular angiocardiogram, AP projection. The arrow points to the narrowed ostium of the outtlow tract. pulmonic valve leaflets appeared mobile and fine in structure. The main pulmonary artery and its branches, the pulmonary circulation, the left atrium and ventricle, and the thoracic aorta were all visualized and were normal.
A 58-year-old married woman, mother of one child, had She underwent known of a heart murmur since &ilc&@.
RGURE 2. (Case 1). Right ventricular angiocardiogram, later-. al projection. The arrow delineates the narrow oblique muscular band which narrows the ostium of the infundibulum.
CHEST, 67: 6, JUNE, 1975
three operations in the past: subtotal gastrectomy for peptic ulcer, herniorraphy, and hysterectomy for fibromyomata. She was asymptomatic. On physical examination there was no apparent cyanosis and she appeared healthy. The arterial pulses. and neck veins were normal and there were no signs of congestive heart failure. The apex beat was felt in the 5th intercostal space between the midclavicular line and the anterior axillary line, but there were no abnormal lifts. A prominent systolic t h d l was felt at the left lower sternal border. On a d t a t i o n , a long, coarse systolic ejection murmur, 4/6, was heard, maximal at the 1ower.left sternal border, radiating to the apex and toward the base. The second sound split normally on inspiration. The electrocardiogram showed a frontal axis of about +10O0 and inverted T waves in the right precordial leads, suggestive of right ventricular hypertrophy. The heart was mildly enlarged and pulmonary vasculature appeared normal on the chest roentgenogram. The findings on cardiac catheterization are given in Table 1. There was a systolic gradient of 64 mm Hg on pull-back from the infundibulum to the body of the right ventricle. Oxygen saturation determinatio~~s and dye dilution curves showed no evidence of a shunt at either direction. Right ventricular angioadbgmphy was performed (Fig 3 and 4). A wide band stretching obliquely across the right ventricle was seen, above which the outBow tract was markedly dilated. The pulmonic valve appeared normal. The pulmonary trunk was dilated, but its branches were normal, as were the pulmonary vasculature, the left atrium and ventricle and the aorta.
Anomalous right ventricular muscle bundle must be clearly distinguished from other, more common forms of subvalvular outflow obstruction. In this lesion the obstruction is below the level of the infundibulum and is caused by one or more aberrant muscular bands which traverse the right ventricular cavity from the anterior wall to the septum at or near the crista supraventri~ularis.~The ven-
FIGURE3. (Case 2). R i d t ventricular anniocardiomam. AP projection. A broad hus& waist (anow4 narrows thearea between the right ventricular cavity ( RV) and its oudow tract (I).
ISOLATED ANOMALOUS RIGHT VENTRICULAR MUSCLE BUNDLE 693
FIGURE4. ( Case 2 ) . Right ventricular angiocardiogram, lateral projection. The oblique position of the muscular band within the right ventricle is shown (arrows).
tricle is divided into a proximal, high pressure chamber and a distal, low pressure chamber. The lesion is generally considered to be a congenital although occasionally it may be first diagnosed in a patient well up into adulthood, a fact confinned by our two cases. Forster and Humphries,' in their review of the literature in 1971, found 42 reported cases of anomalous right ventricular muscle bundle, and added 19 cases of their own. Since then, an additional nine cases have been making a total of 70 cases in the literature. In the vast majority of these cases, the diagnosis was made in infancy or childhood; in only 7 patients was the disease discovered in adulthood, the oldest being 59. Of the 70 cases previously reported, 58 had associated cardiovascular anomalies (ventricular septal defect in 46, pulmonic stenosis in 9, and other anomalies in 3). Only 12 cases were free of significant associated anomalies, although one had a right aortic arch,' and another had slight thickening and deformity of the pulmonic and aortic valves, but without stenosis.1° The age of diagnosis of these 12 patients ranged from 5 days to 59 years, but only 2 of them were adults (aged 30 and 59
694 WANDERMAN ET A 1
years). Thus our report adds two more adult cases of anomalous right ventricular muscle bundle. Our two patients showed the characteristic clinical findings emphasized by Gale: but without the features related to a coexistent ventricular septal defect. In both cases there was a long, loud, c o k e ejection munnur at the left sternal border, suggesting severe outflow obstruction, but no right ventricular lift as would be expected if severe obstruction were at the valvular or infundibular level. Furthermore, the pulmonic closure sound was normal, there was no ejection click, and the murmur was maximal at the lower sternal border. The diagnosis was suspected clinically on the basis of these findings, and confirmed by the very characteristic angiocardiographic picture which fits the description given by Barnes and colleag~es.~ The band-like filling defect crossing the ventricular cavity and producing a narrowing between the lower end of the infundibulum and the ventricular cavity, is clearly demonstrated in both cases. This angiocardiographic picture is distinct from that seen in cases of idiopathic hypertrophic cardiomyopathy obstructing right ventricular outflow, as in the latter case the films show narrowing of the outflow tract by a hypertrophied ventricular septum." Our patients demonstrate that the condition may give rise to no disability or symptoms for many years, in spite of the presence of a very significant pressure gradient ( 130 rnm Hg in the first case). This asymptomatic state in the adult patient with a congenital lesion invites the conclusion that surgical correction may not be called for in these cases. However, the outflow obstruction has been shown to be progressive in several cases.' The advisability of surgery in adult cases similar to ours is, therefore, debatable, and only further experience with such cases will provide the answer. 1 Lockhart A, Charpentier A, Bourdavias JP, et al: Right ventricular involvement in obstructive cardiomyopathies. Br Heart J 28:122, 1966 2 Falcone DM, Moore D, Larnbert EC: Idiopathic hypertrophic cardiomyopathy involving the right ventricle. AM J Cardiol 19:735, 1967 3 Lucas RV Jr, Varco RL. Lillehei CW,et al: Anomalous muscle bundle of the right ventricle. Circulation 25:443, 1962 4 Forster JW. Humphries JO: Right ventricular anomalous muscle bundle. Circulation 43: 115, 1971 5 Perloff JK, Ronan JA, de Leon AC: Ventricular septa1 defect with two-chambered right ventricle. Am J Cardiol 16:894. 1965 6 Hindle MV Jr, Engle MA, Hagstrom JWC: Anomalous right ventricular muscles. Am J Cardiol21:487, 1968 7 Gale GE, Heiman, KW, Barlow JB: Double-chambered
CHEST, 67: 6, JUNE, 1975
right ventricle. A report of five cases. Br Heart J 31: 291, 1969 8 Barnes RJ, Kwong KH, Cheung ACS: Aberrant muscle bundle of the right ventricle. Br Heart J 33:546, 1971 9 Pate1 R, Astley R: Right ventricular obstruction due to anomalous muscle bands. Br Heart J 35: 890, 1973
10 Hartmann AF, Tsifutis AA, Arvidsson H, et al: The twochambered right ventricle. Circulation 26:270, 1962 11 Barr PA, Celermajer JM, Bowdler JD, et al: Idiopathic hypertrophic obstructive cardiomyopathy causing severe right ventricular outflow tract obstruction in infancy. Br Heart J 35: 1109, 1973
Horner's Syndrome This syndrome has been found a valuable semaphore by those with particular interest in thoracic medicine, and surgery. Basically, it is due to interference with the functioi of sympathetic nerve structures, including central cells in the hypothalamus and medulla, the trunk, connecting white rarni and descending pathways in the brain stem or spinal cord. Possible causal factors are: enlarged lymph nodes in the neck, superior sulcus tumor, primary or metastatic neoplasms in the apical region of the lung; also, high mediastinal tumors, extensive infiltrative processes i n the lower cervical region, aortic aneurysm, carcinoma of the esophagus, thoracic wall tumors, and enlarged thyroid. Sataline, L R et al (New Engl J Med 272:1227, 1967) &st reported the occurrence of Homer's syndrome in spontaneous pneum* thorax. It was presumed to have been brought about by mediastinal shift and consequent traction on sympathetic ganglions. Similar instances were observed by Osterman, P 0 et al (Scand J Resp Dis 52:230, 1971), and by Aston, S J et al (New Engl J Med 287:1098, 1972). Complete reexpansion of the lung was followed by disappearance of Homer's syndrome in a few days. It may not be amiss to suggest that its infrequent occurrence in spontaneous pneurnothorax is caused by some uncommon anatomic or functional anomaly. Other causes of Homer's syndrome include pachymeningitis and radiculitis in the low cervical and upper thoracic region (C,-TI), trauma to and penetrating wounds of the neck, surgical procedures in the same area, birth injury, cervical rib, spasmodic torticollis, pontine tumor, multiple sclerosis, encephalitis, acute anterior poliomyelitis, and tumor of the Gasserian ganglion compromising the carotid sympathetic plexus. Kunkle, E C (in Beeson, P B et a1 ( e d ) : Cecil-Loeb Textbook of Medicine, Philadelphia, Saunders, 1963) lists additional causal factors, such as brain stem lesions, cervical and
CHEST, 67: 6, JUNE, 1975
high thoracic cord involvement by syringomyelia, hematomyelia, or tumors, thrombosis or aneurysm of the internal carotid trunk, attacks of certain forms of migrain, notably "cluster headache." Homer's syndrome may be part of Wallenberg's syndrome which is due to thrombotic occlusion of the posterior inferior cerebellar artery. Also, Homer's syndrome may be observed in combination with DBjerine-Klurnke's syndrome due to involvement of the eighth cervical and first dorsal roots. Sometimes Homer's svndrome develo~sas a side effect of phenothiazines. Congenital Homer's syndrome is rare. Characteristic manifestations of Homer's syndrome are brought about by unilateral paresis or paralysis of some of the orbital muscles: dilator fibers of the iris, the superior tarsal muscle and Mdler's orbital muscle. Consequent changes are: miosis (the pupil reacts to light and in accommodation) ; ptosis (sometimes referred to as pseudoptosis because the eye lid can be raised volitionally by the levator palpabrae superior innervated by the intact oculomotor nerve); enophthalmos may be more illusory than real. Additional findings may be noted, such as unilateral decrease or absence of sweating on the face, head, neck and upper extremity caused by loss of sudomotor control; unilateral hyperemia and elevated skin temperature over the same areas, due to lack of vasomotor control; unilateral depigmentation of the iris, and edema of the eye lid. It is a curious example of conservative traditionalism that the accepted eponymic designation of this syndrome has been established since the publication of a case report by Homer, J F (Klin Mblat Augenheilk 7:193, 1869) even though prior reports by Francois Pourfour du Petit (1727), Claude Bernard, Hare, E S (1839), and Mitchel, S W et al ( 1864) canied accurate description of experimental and clinical findings ( Editorial JAMA 208: 1899, 1969). Andrew L. Banyai, M.D.
ISOLATED ANOMALOUS RIGHT VENTRICULAR MUSCLE BUNDLE 695
asymptomatic adults with severe obstruction due to a right ventricular muscular band as an isolated lesion are presented. The lesion can be tentatively diagnosed on clinical grounds and confirmed by angiocardiography. The advisability of surgical correction in the asymptomatic aduit with such an isolated lesion is uncertain.
uscular obstruction to right ventricular outflow is not an uncommon finding when associated with other cardiac lesions. It is frequently seen in tetralogy of Fallot and in pulmonic stenosis with intact ventricular septum. It can also occur in cases of idiopathic hypertrophic cardiomyopaIn these cases the obstruction is due to hypertrophied muscle protruding from the infundibular walls. Less commonly, right ventricular outflow may be interfered with by an anomalous muscle bundle arising proximal to the infundibulurn and crossing the right ventricular c a ~ i t y .This ~ lesion is also, in the vast majority of cases, not an isolated one, almost always being associated with a ventricular septa1 defect or other anomalies. The purpose of this report is to present two asymptomatic adults with anomalous right ventricular muscle bundle in the absence of any detectable associated defects.
sternum., and., to a lesser extent. to the apex. The second heart sound was normal. The electrocardiogram showed a frontal axis of about +90°, an RS pattern in the chest leads with a notched R wave of 6 to 8 mm in V1,and peaked P waves, and the vectorcardiogram confirmed the diagnosis of right ventricular hypertrophy. On the chest roentgenogram, the heart was mildly enlarged and pulmonary vasculature a p peared normal. The findings on cardiac catheterization are given in Table 1. A systolic gradient of 130 mm Hg was found on pull-back from the infundibulum to the body of the right ventricle. Oxygen saturation determinations and dve dilution curves in the right heart cavities showed no evidence of a shunt in either direction. Right ventricular angiocardiography was performed (Fig 1 and 2 ) . An obliquely placed bandlike filling defect was seen, narrowing the entrance to the infundibulum. The
-
Table 1 4 a t h e t e r i d o n Finding.
CASE1 Pressure Ot Satumm Hg ration ?&
Location
CASE2 Pressure Ot Satumm Hg ration QJo
Superior vena cava Right atrium A 38-vear-old married woman. mother of two children. was examined because of a heart murmur discovered on routine examination several years previously. She was asymptomatic. On physical examination she was well developed and appeared healthy; there was no cyanosis. The arterial pulses were normal. Mildly prominent "A" waves were visible in the neck veins. The apex beat was not felt and there were no abnormal lifts. A systolic thrill was felt along the left lower sternal border. On auscultation, a long, harsh, ejection-type systolic murmur, grade 4/6, was heard-maximal at the left sternal border in the 3rd to 5th intercostal space; radiating upwards to the 2nd left intercostal space, to the right of the *From the Cardiac Laboratory and Deparhnent of Radiology, Soroka Medical Center, Beer-Sheva, Israel. Manuscript received August 26; revision accepted October 24. Reprint requests: Dr. Gueron, Negeo Central Hospital, Beer Sheoa, Israel
692 WANDERMAN ET A1
high mid low Right ventricle inflow tract apex outflow tract Pulmonary artery main right left Brachial artery ---
a =a wave
-
-
-
-
v = v wave
-
-
m =mean
CHEST, 67: 6, JUNE, 1975
FIGURE1. (Case 1). Right ventricular angiocardiogram, AP projection. The arrow points to the narrowed ostium of the outtlow tract. pulmonic valve leaflets appeared mobile and fine in structure. The main pulmonary artery and its branches, the pulmonary circulation, the left atrium and ventricle, and the thoracic aorta were all visualized and were normal.
A 58-year-old married woman, mother of one child, had She underwent known of a heart murmur since &ilc&@.
RGURE 2. (Case 1). Right ventricular angiocardiogram, later-. al projection. The arrow delineates the narrow oblique muscular band which narrows the ostium of the infundibulum.
CHEST, 67: 6, JUNE, 1975
three operations in the past: subtotal gastrectomy for peptic ulcer, herniorraphy, and hysterectomy for fibromyomata. She was asymptomatic. On physical examination there was no apparent cyanosis and she appeared healthy. The arterial pulses. and neck veins were normal and there were no signs of congestive heart failure. The apex beat was felt in the 5th intercostal space between the midclavicular line and the anterior axillary line, but there were no abnormal lifts. A prominent systolic t h d l was felt at the left lower sternal border. On a d t a t i o n , a long, coarse systolic ejection murmur, 4/6, was heard, maximal at the 1ower.left sternal border, radiating to the apex and toward the base. The second sound split normally on inspiration. The electrocardiogram showed a frontal axis of about +10O0 and inverted T waves in the right precordial leads, suggestive of right ventricular hypertrophy. The heart was mildly enlarged and pulmonary vasculature appeared normal on the chest roentgenogram. The findings on cardiac catheterization are given in Table 1. There was a systolic gradient of 64 mm Hg on pull-back from the infundibulum to the body of the right ventricle. Oxygen saturation determinatio~~s and dye dilution curves showed no evidence of a shunt at either direction. Right ventricular angioadbgmphy was performed (Fig 3 and 4). A wide band stretching obliquely across the right ventricle was seen, above which the outBow tract was markedly dilated. The pulmonic valve appeared normal. The pulmonary trunk was dilated, but its branches were normal, as were the pulmonary vasculature, the left atrium and ventricle and the aorta.
Anomalous right ventricular muscle bundle must be clearly distinguished from other, more common forms of subvalvular outflow obstruction. In this lesion the obstruction is below the level of the infundibulum and is caused by one or more aberrant muscular bands which traverse the right ventricular cavity from the anterior wall to the septum at or near the crista supraventri~ularis.~The ven-
FIGURE3. (Case 2). R i d t ventricular anniocardiomam. AP projection. A broad hus& waist (anow4 narrows thearea between the right ventricular cavity ( RV) and its oudow tract (I).
ISOLATED ANOMALOUS RIGHT VENTRICULAR MUSCLE BUNDLE 693
FIGURE4. ( Case 2 ) . Right ventricular angiocardiogram, lateral projection. The oblique position of the muscular band within the right ventricle is shown (arrows).
tricle is divided into a proximal, high pressure chamber and a distal, low pressure chamber. The lesion is generally considered to be a congenital although occasionally it may be first diagnosed in a patient well up into adulthood, a fact confinned by our two cases. Forster and Humphries,' in their review of the literature in 1971, found 42 reported cases of anomalous right ventricular muscle bundle, and added 19 cases of their own. Since then, an additional nine cases have been making a total of 70 cases in the literature. In the vast majority of these cases, the diagnosis was made in infancy or childhood; in only 7 patients was the disease discovered in adulthood, the oldest being 59. Of the 70 cases previously reported, 58 had associated cardiovascular anomalies (ventricular septal defect in 46, pulmonic stenosis in 9, and other anomalies in 3). Only 12 cases were free of significant associated anomalies, although one had a right aortic arch,' and another had slight thickening and deformity of the pulmonic and aortic valves, but without stenosis.1° The age of diagnosis of these 12 patients ranged from 5 days to 59 years, but only 2 of them were adults (aged 30 and 59
694 WANDERMAN ET A 1
years). Thus our report adds two more adult cases of anomalous right ventricular muscle bundle. Our two patients showed the characteristic clinical findings emphasized by Gale: but without the features related to a coexistent ventricular septal defect. In both cases there was a long, loud, c o k e ejection munnur at the left sternal border, suggesting severe outflow obstruction, but no right ventricular lift as would be expected if severe obstruction were at the valvular or infundibular level. Furthermore, the pulmonic closure sound was normal, there was no ejection click, and the murmur was maximal at the lower sternal border. The diagnosis was suspected clinically on the basis of these findings, and confirmed by the very characteristic angiocardiographic picture which fits the description given by Barnes and colleag~es.~ The band-like filling defect crossing the ventricular cavity and producing a narrowing between the lower end of the infundibulum and the ventricular cavity, is clearly demonstrated in both cases. This angiocardiographic picture is distinct from that seen in cases of idiopathic hypertrophic cardiomyopathy obstructing right ventricular outflow, as in the latter case the films show narrowing of the outflow tract by a hypertrophied ventricular septum." Our patients demonstrate that the condition may give rise to no disability or symptoms for many years, in spite of the presence of a very significant pressure gradient ( 130 rnm Hg in the first case). This asymptomatic state in the adult patient with a congenital lesion invites the conclusion that surgical correction may not be called for in these cases. However, the outflow obstruction has been shown to be progressive in several cases.' The advisability of surgery in adult cases similar to ours is, therefore, debatable, and only further experience with such cases will provide the answer. 1 Lockhart A, Charpentier A, Bourdavias JP, et al: Right ventricular involvement in obstructive cardiomyopathies. Br Heart J 28:122, 1966 2 Falcone DM, Moore D, Larnbert EC: Idiopathic hypertrophic cardiomyopathy involving the right ventricle. AM J Cardiol 19:735, 1967 3 Lucas RV Jr, Varco RL. Lillehei CW,et al: Anomalous muscle bundle of the right ventricle. Circulation 25:443, 1962 4 Forster JW. Humphries JO: Right ventricular anomalous muscle bundle. Circulation 43: 115, 1971 5 Perloff JK, Ronan JA, de Leon AC: Ventricular septa1 defect with two-chambered right ventricle. Am J Cardiol 16:894. 1965 6 Hindle MV Jr, Engle MA, Hagstrom JWC: Anomalous right ventricular muscles. Am J Cardiol21:487, 1968 7 Gale GE, Heiman, KW, Barlow JB: Double-chambered
CHEST, 67: 6, JUNE, 1975
right ventricle. A report of five cases. Br Heart J 31: 291, 1969 8 Barnes RJ, Kwong KH, Cheung ACS: Aberrant muscle bundle of the right ventricle. Br Heart J 33:546, 1971 9 Pate1 R, Astley R: Right ventricular obstruction due to anomalous muscle bands. Br Heart J 35: 890, 1973
10 Hartmann AF, Tsifutis AA, Arvidsson H, et al: The twochambered right ventricle. Circulation 26:270, 1962 11 Barr PA, Celermajer JM, Bowdler JD, et al: Idiopathic hypertrophic obstructive cardiomyopathy causing severe right ventricular outflow tract obstruction in infancy. Br Heart J 35: 1109, 1973
Horner's Syndrome This syndrome has been found a valuable semaphore by those with particular interest in thoracic medicine, and surgery. Basically, it is due to interference with the functioi of sympathetic nerve structures, including central cells in the hypothalamus and medulla, the trunk, connecting white rarni and descending pathways in the brain stem or spinal cord. Possible causal factors are: enlarged lymph nodes in the neck, superior sulcus tumor, primary or metastatic neoplasms in the apical region of the lung; also, high mediastinal tumors, extensive infiltrative processes i n the lower cervical region, aortic aneurysm, carcinoma of the esophagus, thoracic wall tumors, and enlarged thyroid. Sataline, L R et al (New Engl J Med 272:1227, 1967) &st reported the occurrence of Homer's syndrome in spontaneous pneum* thorax. It was presumed to have been brought about by mediastinal shift and consequent traction on sympathetic ganglions. Similar instances were observed by Osterman, P 0 et al (Scand J Resp Dis 52:230, 1971), and by Aston, S J et al (New Engl J Med 287:1098, 1972). Complete reexpansion of the lung was followed by disappearance of Homer's syndrome in a few days. It may not be amiss to suggest that its infrequent occurrence in spontaneous pneurnothorax is caused by some uncommon anatomic or functional anomaly. Other causes of Homer's syndrome include pachymeningitis and radiculitis in the low cervical and upper thoracic region (C,-TI), trauma to and penetrating wounds of the neck, surgical procedures in the same area, birth injury, cervical rib, spasmodic torticollis, pontine tumor, multiple sclerosis, encephalitis, acute anterior poliomyelitis, and tumor of the Gasserian ganglion compromising the carotid sympathetic plexus. Kunkle, E C (in Beeson, P B et a1 ( e d ) : Cecil-Loeb Textbook of Medicine, Philadelphia, Saunders, 1963) lists additional causal factors, such as brain stem lesions, cervical and
CHEST, 67: 6, JUNE, 1975
high thoracic cord involvement by syringomyelia, hematomyelia, or tumors, thrombosis or aneurysm of the internal carotid trunk, attacks of certain forms of migrain, notably "cluster headache." Homer's syndrome may be part of Wallenberg's syndrome which is due to thrombotic occlusion of the posterior inferior cerebellar artery. Also, Homer's syndrome may be observed in combination with DBjerine-Klurnke's syndrome due to involvement of the eighth cervical and first dorsal roots. Sometimes Homer's svndrome develo~sas a side effect of phenothiazines. Congenital Homer's syndrome is rare. Characteristic manifestations of Homer's syndrome are brought about by unilateral paresis or paralysis of some of the orbital muscles: dilator fibers of the iris, the superior tarsal muscle and Mdler's orbital muscle. Consequent changes are: miosis (the pupil reacts to light and in accommodation) ; ptosis (sometimes referred to as pseudoptosis because the eye lid can be raised volitionally by the levator palpabrae superior innervated by the intact oculomotor nerve); enophthalmos may be more illusory than real. Additional findings may be noted, such as unilateral decrease or absence of sweating on the face, head, neck and upper extremity caused by loss of sudomotor control; unilateral hyperemia and elevated skin temperature over the same areas, due to lack of vasomotor control; unilateral depigmentation of the iris, and edema of the eye lid. It is a curious example of conservative traditionalism that the accepted eponymic designation of this syndrome has been established since the publication of a case report by Homer, J F (Klin Mblat Augenheilk 7:193, 1869) even though prior reports by Francois Pourfour du Petit (1727), Claude Bernard, Hare, E S (1839), and Mitchel, S W et al ( 1864) canied accurate description of experimental and clinical findings ( Editorial JAMA 208: 1899, 1969). Andrew L. Banyai, M.D.
ISOLATED ANOMALOUS RIGHT VENTRICULAR MUSCLE BUNDLE 695