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Left Atrial-to-Right Atrial Shunt without Atrial Septal Defect or Precordial Murmur
STRUCTURE -FUNCTION CORRELATIONS IN CARDIOVASCULAR AND PULMONARY DISEASES (CPC) Left Atrial-to-Right Atrial Shunt without Atrial Septal Defect or Precordial Murmur* Pulmonary Varix and Hypertrophic Cardiomyopathy Frank C. Brosius, III, M.D.; David E. Schwartz, M.D.; William L. Gleason, M.D.; Barry Maron, M.D.; Michael Jones, M.D.; and William C. Roberts, M.D., F.C.C.P.
Pulmonary varix is infrequent, and when present, is usually clinically silent and found only as an incidental finding on chest roentgenogram. Hypertrophic cardiomyopathy, in contrast, is fairly frequent, and when present, is frequently clinically apparent. When the two occur together in the same patient, however, the pulmonary varix (with anomalous systemic venous connection) may become clinically apparent, the second (hypertrophy cardiomyopathy), the real culprit, may remain clinically silent and the combination may present challenging diagnostic and therapeutic difficulties which are described below. A 49-year-old man who died on February 7, 1980, was found to have left ventricular hypertrophy on electrocardiogram dUring a routine examination at age 32 years (1963) (Fig 1). Cardiac catheterization disclosed a 19 mm Hg peak systolic pressure gradient between the left ventricle and aorta and a 2.8:1 left-to-right shunt via a large vein in the upper lobe of the left lung which connected to a vertical vein which in tum connected to the innominate vein. He was asymptomatic until age 43 when exertional dyspnea and excessive fatigue appeared. Intermittent atrial flutter and fibrillation appeared the following year, and congestive cardiac faaure became overt and progressively worsened thereafter. Angiography at age 48 disclosed a dilated and diffusely hypocontractile left ventricle and a year later, the electrocardiogram showed marked diminution of amplitude of QRS complexes and loss or severe diminution of R waves in the precordial leads. At age 48, bilateral pleural -From the Pathology, Cardiology and Surgery Branches, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, and the Department of Medicine, Watson Clinic, Lakeland. Florida. Reprint requeste: Dr. Rtib~, B~ lOA, Rm 3E30, Na-
fIofwllfl8titutes of Health,
lSeUlUQQ
CHEST, 81: 1, JANUARY, 1982
20205
effusions appeared and persisted thereafter. When hospitalized on January 23, 1980, he was cachectic, dyspneic and dehydrated. He had never had chest pain. The neck veins were greatly distended; the liver, large, and the legs, non-edemataus. The heart was large (Fig 2). A third heart sound was present but there was no precordial murmur. Electrocardiogram (Fig 1) now disclosed left
FIGllIm 1. Electrocardiograms recorded at ages 32, 47 and 49
years, respectively (top to
bottom).
LEFT ATRIAl·TO-RI6HT ATRIAL SHUIfr 91
FIGURE 2. Posteroanterior (left) and lateral roentgenograms (middle) taken two weeks· before death, and the left lung (right) at necropsy with the pulmonary varix dissected free. The pulmonary varix is seen well in both radiographs.
anterior hemiblock. On echocardiogram (Fig 3),
both ventricular cavities were dilated and the ventricular septum and the left ventricular free wall were of similar thickness. Cardiac catheterization was repeated (Table 1). To exclude pericardial constriction, median sternotomy was performed: large pleural effusions were found but the pericardia were normal and the pericardial space was free of adhesions and excess fluid. The left vertical vein (Fig 4) measured up to 2.2 em in diameter and the innominate vein, to 3.0 em. Postoperation, he was .hypotensive despite therapy with oosopressors and aortic balloon counterpulsation, the right-sided intracardiac pressures remained elevated, and the leftto-right shunt increased progressively from 3:1 to 11:1. Reoperation was done four hours after the first: the vertical vein was divided and anastomosed to the left atrium, but the patient could not be separated from cardiopulmonary bypass.
At necropsy, the heart weighed 54() gm. All four cardiac chambers were mildly dilated. The ventricular septum and left ventricular free waU were of similar thickness (1.7 em). Both the ventricular septum and anterior portion of left ventricular free wall were extensively replaced by dense fibrous tissue (Fig 5). The cardiac valves and mural endocardium were normal. Of the 39 5-mm long segments of the left main, left anterior descending, left circumflex and right coronary arteries, none was narrowed 51-1()() percent; 27 (69 percent) were narrowed 26-50 percent, and 12 (31 percent), 0-25 percent, in cross-sectional area by atherosclerotic plaques. Most of the intramural coronary arteries in the ventricul.ar septum had thickened walls and a few, na"owed lumens. On quantitative analysis of transversely-cut sections of ventricular septum by a method described previously,l 40 percent of the myocardium was disorganized (normal = <5 per-
FIGURE 3. Echocardiogram recorded a week before death. The ventricular septum (VS) measures 15 mm and the left ventricular free wall, 14 mm in thickness. Both right (RV) and left ventricular cavities are dilated. A pericardia1 effusion (PE) is present. MV = mitral valve.
92 BROSIUS ET AL
CHEST, 81: 1, JANUARY, 1982
developed a large anteroseptal myocardial infarct which also was clinically silent, but which also is a well-recognized complication of hypertrophic cardiomyopathy," Nearly one-half of the ventricular septum consisted of disorganized myocardial fibers and many intramural coronary arteries were thickened, both findings being typical of hypertrophic cardiomyopathy. 1,3
4. Diagram of the pulmonary varix and its connection to left atrium and to an anomalous systemic vein. The flow of blood in the varix is reverse of that which might have been expected had the heart been normal. IYC = inferior vena cava; LA = left atrium; LV = left ventricle; RA = right atrium; RV right ventricle and SVC superior vena cava. FiCUBE
=
=
cent); of similarly cut sections of anterior and pos-
terior left ventricular free wall, 7 percent and 3 per-
cent, respectively, were disorganized (normal < 10 percent). The varix was located in the lingular portions of the left upper lobe of the lung (Fig 2 and 4). Its maximal diameter was 2.5 em and its wall was thin. The pulmonary parenchyma and pulmonary arteries were normal. DISCUSSION
Although it was appreciated that the left-to-right shunt could hardly explain all the clinical, electrocardiographic, hemodynamic and radiographic findings, the presence of hypertrophic cardiomyopathy in the above described patient was never appreciated clinically. The diagnosis of hypertrophic cardiomyopathy at necropsy, however, was clear. He had left ventricular hypertrophy without (at least initially) left ventricular dilatation, systemic hypertension, supravalvular, valvular or discrete subvalvular aortic stenosis, and (at least initially) with a normal or supranormal cardiac output. He
CHEST, 81: 1, JANUARY, 1982
The pulmonary varix which connected to an anomalous systemic vein and to the left atrium would probably have caused little to no symptoms of cardiac dysfunction had not hypertrophic cardiomyopathy also been present. With a normal left ventricle, its filling would have been unimpeded, thereby minimizing the left-to-right shunt through the pulmonary varix. The considerable left ventricular hypertrophy and scarring caused by the hypertrophic cardiomyopathy undoubtedly diminished left ventricular compliance, favoring drainage of oxygenated blood retrogradely through the pulmonary varix, with subsequent drainage into the anomalous systemic vein which in turn connected to the innominate vein, allowing for a left-atrial-toright-atrial shunt without an atrial septal defect. A similar pathway, incidentally, has been described in several patients with mitral valve atresia and partial anomalous pulmonary venous connection.' Physiologically, the circumstance in our patient is similar to that in patients with mitral stenosis associated with atrial septal defect (Lutembacher's syndrome )." As in patients with Lutembacher's syndrome, the anomalous venous connection in our patient presumably relieved the left-sided congestive cardiac failure which might have been expected from the associated hypertrophic cardiomyopathy and augmented signs and symptoms of right-sided cardiac failure. Certainly, the presence of severe jugular venous distension and hepatomegaly without pulmonary edema, orthopnea or nocturnal dyspnea is atypical for hypertrophic cardiomyopathy and favors this hypothesis. The equal and elevated end-diastolic pressures in all four cardiac chambers also might be explained from the elevated left-sided pressures (due to the cardiomyopathy) which were transmitted to the right side of the heart through the anomalous venous connection. The pulmonary varix in our patient was unusual not only in occurring in association with ,hypertrophic cardiomyopathy, but also in connecting to an anomalous systemic vein, an occurrence not hitherto reported. The varix was located in the left upper lobe which is the second most common site for varices," The varix presented typical radiographic features (vascular shadow) with delayed filling in the levophase on angiogram," At necropsy, the
LEfT ATRIAL·THI8HT ATRIAL SHUNT 93
FlcuRE 5. The heart. tJ anteroposterior cut (similar to that of the M-mode echo beam) showing the relative thickness of the right ventricular (RV), ventricular septal (VS) and left ventricular ( LV) waIls and the sizes of the ventricular cavities. A anterior leaSet of the mitral valve; LA = left atrium; RA = right atrium. b dose-up of mitral valve area. The most basal portion of left ventricular free waD is thinner than that in the mid-portion, the reverse of normal. A subepicardiaI scar. a fairly frequent occurrence in hypertrophic cardiomyopathy. is partially enclosed by brackets and a close-up photomicrognph (KI6) of the area in brackets is shown in d. c A more anterior cut of the ventricles showing many transmmal ventricular scars (tJn'OlD8).
=
varix was tortuous, thin-walled and obviously aneurysmal compared to other pulmonary veins. Alth gh all be' ulm' au usn ~ ~gn, p onary v~ ma~ roptore, as descnbed m at least three patients." The relatively frequent association of pulmonary varices with other cardiac and pulmonary abnormalities,lo however, indicates that patients with pulmonary varices should be examined for associated or additiona! cardiopulmonary abnormalities.
1 Maron BJ. Roberts WC. Quantitative analysis of cardiac muscle cell disorganization in the ventricular septun1 of
patients with hypertrophic cardiomyopathy. Circulation 1979; 59:689-706 2 Maron BJ, Epstein SE, Roberts WC. Hypertrophic cardiomyopathy and transmmal myocardial infarction without , significant atherosclerosis of the extrammal coronary arteries. Am J Cardiol 1979; 43:1086-1102
14 BROSIUS ET At
3 McReynolds RA, Roberts WC. The intrammal coronary arteries in hypertrophic cardiomyopathy (abstract). Am
J Cardioll975; 35:154 4 Shone JD. Edwards }E. Mitral atresia associated with pulmonary venous anomalies. Dr Heart J 1964· 26:241-49 5 Steinbrunn W. Cohn ICE. Selzer A. Atrial ~tal defect associated with mitral stenosis: the Lutembacher syndrome revisited. Am J Moo 1970; 48:295-302 6 Romanoff H, Manny J, Aviad I. Pulmonary varices. Report of two cases and review of the literature. Chest J976; 70:395-97 7 Poller S, Wholey MH: Pulmonary varix: evaluation by IIelective pulmonary angiography. Radiology 1966; 88: 1078-81 8 Klinch GH Jr. Hunt HD. Pulmonary varix with spontaneous rupture and death. Arch PathoI1933; 15:227-37 9 Perret L, ForteliUJ P. Ruptured aneurysm of a pulmonary vein. Acta Tuberc Scand 1962; 41:53-55 10 Mom C, Marin E, Sanchez A, SoIozabal J. Pulmonary varix: report of a cue with additional anomalies of the vascular pulmonary tree. Am Heart J 1978; 95 :243-46
CHEST, 81: I, JANUARY, 1982
Pulmonary varix is infrequent, and when present, is usually clinically silent and found only as an incidental finding on chest roentgenogram. Hypertrophic cardiomyopathy, in contrast, is fairly frequent, and when present, is frequently clinically apparent. When the two occur together in the same patient, however, the pulmonary varix (with anomalous systemic venous connection) may become clinically apparent, the second (hypertrophy cardiomyopathy), the real culprit, may remain clinically silent and the combination may present challenging diagnostic and therapeutic difficulties which are described below. A 49-year-old man who died on February 7, 1980, was found to have left ventricular hypertrophy on electrocardiogram dUring a routine examination at age 32 years (1963) (Fig 1). Cardiac catheterization disclosed a 19 mm Hg peak systolic pressure gradient between the left ventricle and aorta and a 2.8:1 left-to-right shunt via a large vein in the upper lobe of the left lung which connected to a vertical vein which in tum connected to the innominate vein. He was asymptomatic until age 43 when exertional dyspnea and excessive fatigue appeared. Intermittent atrial flutter and fibrillation appeared the following year, and congestive cardiac faaure became overt and progressively worsened thereafter. Angiography at age 48 disclosed a dilated and diffusely hypocontractile left ventricle and a year later, the electrocardiogram showed marked diminution of amplitude of QRS complexes and loss or severe diminution of R waves in the precordial leads. At age 48, bilateral pleural -From the Pathology, Cardiology and Surgery Branches, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, and the Department of Medicine, Watson Clinic, Lakeland. Florida. Reprint requeste: Dr. Rtib~, B~ lOA, Rm 3E30, Na-
fIofwllfl8titutes of Health,
lSeUlUQQ
CHEST, 81: 1, JANUARY, 1982
20205
effusions appeared and persisted thereafter. When hospitalized on January 23, 1980, he was cachectic, dyspneic and dehydrated. He had never had chest pain. The neck veins were greatly distended; the liver, large, and the legs, non-edemataus. The heart was large (Fig 2). A third heart sound was present but there was no precordial murmur. Electrocardiogram (Fig 1) now disclosed left
FIGllIm 1. Electrocardiograms recorded at ages 32, 47 and 49
years, respectively (top to
bottom).
LEFT ATRIAl·TO-RI6HT ATRIAL SHUIfr 91
FIGURE 2. Posteroanterior (left) and lateral roentgenograms (middle) taken two weeks· before death, and the left lung (right) at necropsy with the pulmonary varix dissected free. The pulmonary varix is seen well in both radiographs.
anterior hemiblock. On echocardiogram (Fig 3),
both ventricular cavities were dilated and the ventricular septum and the left ventricular free wall were of similar thickness. Cardiac catheterization was repeated (Table 1). To exclude pericardial constriction, median sternotomy was performed: large pleural effusions were found but the pericardia were normal and the pericardial space was free of adhesions and excess fluid. The left vertical vein (Fig 4) measured up to 2.2 em in diameter and the innominate vein, to 3.0 em. Postoperation, he was .hypotensive despite therapy with oosopressors and aortic balloon counterpulsation, the right-sided intracardiac pressures remained elevated, and the leftto-right shunt increased progressively from 3:1 to 11:1. Reoperation was done four hours after the first: the vertical vein was divided and anastomosed to the left atrium, but the patient could not be separated from cardiopulmonary bypass.
At necropsy, the heart weighed 54() gm. All four cardiac chambers were mildly dilated. The ventricular septum and left ventricular free waU were of similar thickness (1.7 em). Both the ventricular septum and anterior portion of left ventricular free wall were extensively replaced by dense fibrous tissue (Fig 5). The cardiac valves and mural endocardium were normal. Of the 39 5-mm long segments of the left main, left anterior descending, left circumflex and right coronary arteries, none was narrowed 51-1()() percent; 27 (69 percent) were narrowed 26-50 percent, and 12 (31 percent), 0-25 percent, in cross-sectional area by atherosclerotic plaques. Most of the intramural coronary arteries in the ventricul.ar septum had thickened walls and a few, na"owed lumens. On quantitative analysis of transversely-cut sections of ventricular septum by a method described previously,l 40 percent of the myocardium was disorganized (normal = <5 per-
FIGURE 3. Echocardiogram recorded a week before death. The ventricular septum (VS) measures 15 mm and the left ventricular free wall, 14 mm in thickness. Both right (RV) and left ventricular cavities are dilated. A pericardia1 effusion (PE) is present. MV = mitral valve.
92 BROSIUS ET AL
CHEST, 81: 1, JANUARY, 1982
developed a large anteroseptal myocardial infarct which also was clinically silent, but which also is a well-recognized complication of hypertrophic cardiomyopathy," Nearly one-half of the ventricular septum consisted of disorganized myocardial fibers and many intramural coronary arteries were thickened, both findings being typical of hypertrophic cardiomyopathy. 1,3
4. Diagram of the pulmonary varix and its connection to left atrium and to an anomalous systemic vein. The flow of blood in the varix is reverse of that which might have been expected had the heart been normal. IYC = inferior vena cava; LA = left atrium; LV = left ventricle; RA = right atrium; RV right ventricle and SVC superior vena cava. FiCUBE
=
=
cent); of similarly cut sections of anterior and pos-
terior left ventricular free wall, 7 percent and 3 per-
cent, respectively, were disorganized (normal < 10 percent). The varix was located in the lingular portions of the left upper lobe of the lung (Fig 2 and 4). Its maximal diameter was 2.5 em and its wall was thin. The pulmonary parenchyma and pulmonary arteries were normal. DISCUSSION
Although it was appreciated that the left-to-right shunt could hardly explain all the clinical, electrocardiographic, hemodynamic and radiographic findings, the presence of hypertrophic cardiomyopathy in the above described patient was never appreciated clinically. The diagnosis of hypertrophic cardiomyopathy at necropsy, however, was clear. He had left ventricular hypertrophy without (at least initially) left ventricular dilatation, systemic hypertension, supravalvular, valvular or discrete subvalvular aortic stenosis, and (at least initially) with a normal or supranormal cardiac output. He
CHEST, 81: 1, JANUARY, 1982
The pulmonary varix which connected to an anomalous systemic vein and to the left atrium would probably have caused little to no symptoms of cardiac dysfunction had not hypertrophic cardiomyopathy also been present. With a normal left ventricle, its filling would have been unimpeded, thereby minimizing the left-to-right shunt through the pulmonary varix. The considerable left ventricular hypertrophy and scarring caused by the hypertrophic cardiomyopathy undoubtedly diminished left ventricular compliance, favoring drainage of oxygenated blood retrogradely through the pulmonary varix, with subsequent drainage into the anomalous systemic vein which in turn connected to the innominate vein, allowing for a left-atrial-toright-atrial shunt without an atrial septal defect. A similar pathway, incidentally, has been described in several patients with mitral valve atresia and partial anomalous pulmonary venous connection.' Physiologically, the circumstance in our patient is similar to that in patients with mitral stenosis associated with atrial septal defect (Lutembacher's syndrome )." As in patients with Lutembacher's syndrome, the anomalous venous connection in our patient presumably relieved the left-sided congestive cardiac failure which might have been expected from the associated hypertrophic cardiomyopathy and augmented signs and symptoms of right-sided cardiac failure. Certainly, the presence of severe jugular venous distension and hepatomegaly without pulmonary edema, orthopnea or nocturnal dyspnea is atypical for hypertrophic cardiomyopathy and favors this hypothesis. The equal and elevated end-diastolic pressures in all four cardiac chambers also might be explained from the elevated left-sided pressures (due to the cardiomyopathy) which were transmitted to the right side of the heart through the anomalous venous connection. The pulmonary varix in our patient was unusual not only in occurring in association with ,hypertrophic cardiomyopathy, but also in connecting to an anomalous systemic vein, an occurrence not hitherto reported. The varix was located in the left upper lobe which is the second most common site for varices," The varix presented typical radiographic features (vascular shadow) with delayed filling in the levophase on angiogram," At necropsy, the
LEfT ATRIAL·THI8HT ATRIAL SHUNT 93
FlcuRE 5. The heart. tJ anteroposterior cut (similar to that of the M-mode echo beam) showing the relative thickness of the right ventricular (RV), ventricular septal (VS) and left ventricular ( LV) waIls and the sizes of the ventricular cavities. A anterior leaSet of the mitral valve; LA = left atrium; RA = right atrium. b dose-up of mitral valve area. The most basal portion of left ventricular free waD is thinner than that in the mid-portion, the reverse of normal. A subepicardiaI scar. a fairly frequent occurrence in hypertrophic cardiomyopathy. is partially enclosed by brackets and a close-up photomicrognph (KI6) of the area in brackets is shown in d. c A more anterior cut of the ventricles showing many transmmal ventricular scars (tJn'OlD8).
=
varix was tortuous, thin-walled and obviously aneurysmal compared to other pulmonary veins. Alth gh all be' ulm' au usn ~ ~gn, p onary v~ ma~ roptore, as descnbed m at least three patients." The relatively frequent association of pulmonary varices with other cardiac and pulmonary abnormalities,lo however, indicates that patients with pulmonary varices should be examined for associated or additiona! cardiopulmonary abnormalities.
1 Maron BJ. Roberts WC. Quantitative analysis of cardiac muscle cell disorganization in the ventricular septun1 of
patients with hypertrophic cardiomyopathy. Circulation 1979; 59:689-706 2 Maron BJ, Epstein SE, Roberts WC. Hypertrophic cardiomyopathy and transmmal myocardial infarction without , significant atherosclerosis of the extrammal coronary arteries. Am J Cardiol 1979; 43:1086-1102
14 BROSIUS ET At
3 McReynolds RA, Roberts WC. The intrammal coronary arteries in hypertrophic cardiomyopathy (abstract). Am
J Cardioll975; 35:154 4 Shone JD. Edwards }E. Mitral atresia associated with pulmonary venous anomalies. Dr Heart J 1964· 26:241-49 5 Steinbrunn W. Cohn ICE. Selzer A. Atrial ~tal defect associated with mitral stenosis: the Lutembacher syndrome revisited. Am J Moo 1970; 48:295-302 6 Romanoff H, Manny J, Aviad I. Pulmonary varices. Report of two cases and review of the literature. Chest J976; 70:395-97 7 Poller S, Wholey MH: Pulmonary varix: evaluation by IIelective pulmonary angiography. Radiology 1966; 88: 1078-81 8 Klinch GH Jr. Hunt HD. Pulmonary varix with spontaneous rupture and death. Arch PathoI1933; 15:227-37 9 Perret L, ForteliUJ P. Ruptured aneurysm of a pulmonary vein. Acta Tuberc Scand 1962; 41:53-55 10 Mom C, Marin E, Sanchez A, SoIozabal J. Pulmonary varix: report of a cue with additional anomalies of the vascular pulmonary tree. Am Heart J 1978; 95 :243-46
CHEST, 81: I, JANUARY, 1982