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Restrictive Cardiomyopathy in a Child
Pediatr Neonatol 2008;49(2):48−51
C ASE R EPORT
Restrictive Cardiomyopathy in a Child Shan-Miao Lin1, Haw-Kwei Hwang1, Ming-Ren Chen1,2* 1
Department of Pediatrics, Mackay Memorial Hospital, Taipei, Taiwan Mackay Medicine, Nursing and Management College, Taipei, Taiwan
2
Received: Jan 11, 2008 Revised: Feb 14, 2008 Accepted: Mar 25, 2008 KEY WORDS: cardiac catheterization; child; restrictive cardiomyopathy
Restrictive cardiomyopathy in young children is rare and carries a poor prognosis. We report an 18-month-old girl with poor feeding and abdominal distension. Except for hepatomegaly, no other gastrointestinal abnormalities were found. She had normalsized ventricles but biatrial enlargement. Echocardiography demonstrated normal systolic but impaired diastolic function. Cardiac catheterization revealed a characteristic dip-and-plateau configuration of the right ventricular pressure tracing. The diagnosis turned out to be typical restrictive cardiomyopathy. The patient was maintained on aspirin while awaiting cardiac transplant.
1. Introduction Restrictive cardiomyopathy is a rare entity in childhood and carries a poor prognosis. Because it is so uncommon, most of our understanding of its clinical and hemodynamic manifestations derives from observations in adults. However, there may be certain distinct features that are specific to its presentation in early childhood. Here, we report a pediatric patient who presented with hepatomegaly as an initial manifestation of restrictive cardiomyopathy.
2. Case Report An 18-month-old girl suffered from progressive abdominal distension and poor feeding for 2 months. Her perinatal course was uneventful, and there was no history of prior viral infection causing heart failure. Physical examination revealed hepatomegaly that was confirmed by abdominal ultrasound. No heart murmur was audible, and there was no significant peripheral edema. Chest radiography
showed slight cardiomegaly, but electrocardiography revealed severe bilateral atrial enlargement and QRS-T discordance (Figure 1). Two-dimensional echocardiography showed dilatation of both atria and a slightly thickened interventricular septum (Figure 2A). The left ventricular (LV) ejection fraction was 0.58, and the left atrial-to-aortic root ratio (LA:Ao) was 1.69. Both ventricles were of normal size (Figure 2B). A small pericardial effusion was present, and the inferior vena cava and hepatic vein were markedly dilated. There was no systolic anterior motion of the mitral valve. Doppler interrogation revealed moderate tricuspid and mitral regurgitation, decreased deceleration of the mitral (70 ms) and tricuspid (80 ms) inflows, faster than normal isovolumic relaxation of the right ventricle (55 ms), and increased E/A ratios of both the mitral (Figure 2C) (E, 91.1 cm/s; A, 26.6 cm/s; E/A, 3.42) and tricuspid (E, 56.8 cm/s; A, 22.2 cm/s; E/A, 2.56) inflows. Cardiac magnetic resonance imaging (MRI) showed no thickening of the pericardium. The child had mild liver dysfunction (aspartate aminotransferase, 46 IU/L) with a prolonged prothrombin
*Corresponding author. Department of Pediatrics, Mackay Memorial Hospital, No. 92, Section 2, Chung-Shan North Road, Taipei 104, Taiwan. E-mail: [email protected] ©2008 Taiwan Pediatric Association
Restrictive cardiomyopathy
Figure 1
49
Electrocardiography shows severe bilateral atrial enlargement and QRS-T discordance.
A
B
C
Figure 2 Echocardiographic findings. (A) Parasternal long-axis view in systole shows a markedly dilated left atrium. (B) Apical four-chamber view in systole. Both right and left atria are markedly enlarged but the ventricles are of normal size and thickness. (C) Pulsed Doppler mitral inflow pattern (leaflet tips) consistent with restrictive physiology, that is, a rapid E-wave deceleration phase, an increased E/A-wave velocity ratio, and decreased isovolumic relaxation time.
time of 15.6 seconds. Cardiac catheterization showed elevated end-diastolic pressure in both ventricles (right ventricle [RV], 13 mmHg; LV, 24 mmHg). The RV pressure tracing demonstrated a characteristic square root sign (an early diastolic dip with a rapid rise to an elevated plateau) and lack of respiratory variation (Figure 3). The pulmonary artery
pressure was 21/16 mmHg. No coronary artery abnormality or other cardiac anomaly was detected. Results of metabolic screening tests were normal. We could not identify any infiltrative disease that would explain the restrictive cardiomyopathy this child had, although we did not perform endomyocardial biopsy because the patient was so young.
Pressure (mmHg)
EKG
50
Figure 3 Simultaneous recording of both left ventricular (LV) and right ventricular (RV) pressures illustrates the early diastolic dip and plateau and nearly equal diastolic pressures characteristic of restrictive cardiomyopathy.
She was maintained on aspirin to prevent atrial thrombus while awaiting cardiac transplant.
3. Discussion The mean ages at diagnosis of restrictive cardiomyopathy in two small pediatric series (each with 8 patients) were 6.3 and 4.0 years, respectively, with the youngest child in the latter series presenting at the age of 1.3 years.1,2 All of the reported patients presented with evidence of congestive heart failure, either systemic venous congestion or pulmonary edema. Other common initial symptoms of restrictive cardiomyopathy in children include failure to thrive, fatigue and syncope.3 Our patient was diagnosed at 1.5 years of age and, aside from nonspecific symptoms, was unusual in having only abdominal distension. Restrictive cardiomyopathy accounts for only approximately 2−5% of all pediatric cardiomyopathies.2,4 Because the number of reported patients is so small,1,2 findings in adult disease are often extrapolated to guide clinical evaluation and management of pediatric patients. There are, however, some important differences. Adults with idiopathic restrictive cardiomyopathy have a relatively prolonged course and reasonably good 5-year survival.5,6 However, in the two reported pediatric series
S.M. Lin et al mentioned above, the average 2-year survival was < 50% from the time of diagnosis.1,2 This difference in survival rate may be due to delayed detection of the disease in children who already have overt congestive heart failure when they present, in contrast to adults, who tend to be diagnosed earlier. The diagnostic criteria for restrictive cardiomyopathy are: (1) marked biatrial dilatation; (2) normal LV chamber size and LV ejection fraction > 50%; (3) LV end-diastolic pressure > 15 mmHg; and (4) LV end-diastolic pressure at least 5 mmHg greater than RV end-diastolic pressure.1 Doppler study reveals diastolic dysfunction consistent with restrictive physiology, namely the typical square root sign. Our patient’s findings were completely compatible with this diagnosis, and she had no evidence of pericardial thickening that would suggest constrictive pericarditis.7 She did not yet have significant pulmonary hypertension at the time of diagnosis because of early detection. Other entities to be considered that may reduce ventricular diastolic compliance include specific infiltrative disorders of the myocardium such as glycogen storage disease, mucopolysaccharidosis, hemochromatosis, amyloidosis, sarcoidosis, and endomyocardial fibrosis.5,8 Our patient’s absence of multiorgan involvement, a history not suggestive of such disease, and the cardiac MRI helped to exclude these possibilities, although we did not do endomyocardial biopsy to rule them out completely. Pediatric restrictive cardiomyopathy carries a high risk for rapidly progressive elevation in pulmonary vascular resistance9 and for sudden death.10 Poor prognostic factors that have been identified include cardiomegaly, age < 5 years, thromboembolism, pulmonary venous congestion, syncope, or chest pain at diagnosis.10,11 An increased echocardiographic LA to Ao ratio at initial presentation is also a strong predictor of poor outcome.3 Because of the poor prognosis of this disease, it is recommended that children with restrictive cardiomyopathy be given preferential status on cardiac transplant waiting lists.10 Our patient’s young age and increased LA to Ao ratio put her at high risk, and she is therefore listed for a cardiac transplant.
References 1.
2. 3. 4.
Kimberling MT, Balzer DT, Hirsch R, et al. Cardiac transplantation for pediatric restrictive cardiomyopathy: presentation, evaluation, and short-term outcome. J Heart Lung Transplant 2002;21:455−9. Lewis AB. Clinical profile and outcome of restrictive cardiomyopathy in children. Am Heart J 1992;123:1589−93. Russo LM, Webber SA. Idiopathic restrictive cardiomyopathy in children. Heart 2005;91:1199−202. Towbin JA. Cardiomyopathies. In: Moller JH, Hoffman JI, eds. Pediatric Cardiovascular Medicine. New York: Churchill Livingstone, 2000:753−67.
Restrictive cardiomyopathy 5. 6. 7.
8.
Benotti JR, Grossman W, Cohn PF. Clinical profile of restrictive cardiomyopathy. Circulation 1980;61:1206−12. Siegel RJ, Shah PK, Fishbein MC. Idiopathic restrictive cardiomyopathy. Circulation 1984;70:165−9. Goldstein JA. Differentiation of constrictive pericarditis and restrictive cardiomyopathy. In: ACC Educational Highlights. Anaheim, California, 1997:14−22. Abelmann WH, Lorell BH. The challenge of cardiomyopathy. J Am Coll Cardiol 1989;13:1219−39.
51 9.
Denfield SW, Rosenthal G, Gajarski RJ, et al. Restrictive cardiomyopathies in childhood. Etiologies and natural history. Tex Heart Inst J 1997;24:38−44. 10. Rivenes SM, Kearney DL, Smith EO, et al. Sudden death and cardiovascular collapse in children with restrictive cardiomyopathy. Circulation 2000;102:876−82. 11. Chen SC, Balfour IC, Jureidini S. Clinical spectrum of restrictive cardiomyopathy in children. J Heart Lung Transplant 2001;20:90−2.
C ASE R EPORT
Restrictive Cardiomyopathy in a Child Shan-Miao Lin1, Haw-Kwei Hwang1, Ming-Ren Chen1,2* 1
Department of Pediatrics, Mackay Memorial Hospital, Taipei, Taiwan Mackay Medicine, Nursing and Management College, Taipei, Taiwan
2
Received: Jan 11, 2008 Revised: Feb 14, 2008 Accepted: Mar 25, 2008 KEY WORDS: cardiac catheterization; child; restrictive cardiomyopathy
Restrictive cardiomyopathy in young children is rare and carries a poor prognosis. We report an 18-month-old girl with poor feeding and abdominal distension. Except for hepatomegaly, no other gastrointestinal abnormalities were found. She had normalsized ventricles but biatrial enlargement. Echocardiography demonstrated normal systolic but impaired diastolic function. Cardiac catheterization revealed a characteristic dip-and-plateau configuration of the right ventricular pressure tracing. The diagnosis turned out to be typical restrictive cardiomyopathy. The patient was maintained on aspirin while awaiting cardiac transplant.
1. Introduction Restrictive cardiomyopathy is a rare entity in childhood and carries a poor prognosis. Because it is so uncommon, most of our understanding of its clinical and hemodynamic manifestations derives from observations in adults. However, there may be certain distinct features that are specific to its presentation in early childhood. Here, we report a pediatric patient who presented with hepatomegaly as an initial manifestation of restrictive cardiomyopathy.
2. Case Report An 18-month-old girl suffered from progressive abdominal distension and poor feeding for 2 months. Her perinatal course was uneventful, and there was no history of prior viral infection causing heart failure. Physical examination revealed hepatomegaly that was confirmed by abdominal ultrasound. No heart murmur was audible, and there was no significant peripheral edema. Chest radiography
showed slight cardiomegaly, but electrocardiography revealed severe bilateral atrial enlargement and QRS-T discordance (Figure 1). Two-dimensional echocardiography showed dilatation of both atria and a slightly thickened interventricular septum (Figure 2A). The left ventricular (LV) ejection fraction was 0.58, and the left atrial-to-aortic root ratio (LA:Ao) was 1.69. Both ventricles were of normal size (Figure 2B). A small pericardial effusion was present, and the inferior vena cava and hepatic vein were markedly dilated. There was no systolic anterior motion of the mitral valve. Doppler interrogation revealed moderate tricuspid and mitral regurgitation, decreased deceleration of the mitral (70 ms) and tricuspid (80 ms) inflows, faster than normal isovolumic relaxation of the right ventricle (55 ms), and increased E/A ratios of both the mitral (Figure 2C) (E, 91.1 cm/s; A, 26.6 cm/s; E/A, 3.42) and tricuspid (E, 56.8 cm/s; A, 22.2 cm/s; E/A, 2.56) inflows. Cardiac magnetic resonance imaging (MRI) showed no thickening of the pericardium. The child had mild liver dysfunction (aspartate aminotransferase, 46 IU/L) with a prolonged prothrombin
*Corresponding author. Department of Pediatrics, Mackay Memorial Hospital, No. 92, Section 2, Chung-Shan North Road, Taipei 104, Taiwan. E-mail: [email protected] ©2008 Taiwan Pediatric Association
Restrictive cardiomyopathy
Figure 1
49
Electrocardiography shows severe bilateral atrial enlargement and QRS-T discordance.
A
B
C
Figure 2 Echocardiographic findings. (A) Parasternal long-axis view in systole shows a markedly dilated left atrium. (B) Apical four-chamber view in systole. Both right and left atria are markedly enlarged but the ventricles are of normal size and thickness. (C) Pulsed Doppler mitral inflow pattern (leaflet tips) consistent with restrictive physiology, that is, a rapid E-wave deceleration phase, an increased E/A-wave velocity ratio, and decreased isovolumic relaxation time.
time of 15.6 seconds. Cardiac catheterization showed elevated end-diastolic pressure in both ventricles (right ventricle [RV], 13 mmHg; LV, 24 mmHg). The RV pressure tracing demonstrated a characteristic square root sign (an early diastolic dip with a rapid rise to an elevated plateau) and lack of respiratory variation (Figure 3). The pulmonary artery
pressure was 21/16 mmHg. No coronary artery abnormality or other cardiac anomaly was detected. Results of metabolic screening tests were normal. We could not identify any infiltrative disease that would explain the restrictive cardiomyopathy this child had, although we did not perform endomyocardial biopsy because the patient was so young.
Pressure (mmHg)
EKG
50
Figure 3 Simultaneous recording of both left ventricular (LV) and right ventricular (RV) pressures illustrates the early diastolic dip and plateau and nearly equal diastolic pressures characteristic of restrictive cardiomyopathy.
She was maintained on aspirin to prevent atrial thrombus while awaiting cardiac transplant.
3. Discussion The mean ages at diagnosis of restrictive cardiomyopathy in two small pediatric series (each with 8 patients) were 6.3 and 4.0 years, respectively, with the youngest child in the latter series presenting at the age of 1.3 years.1,2 All of the reported patients presented with evidence of congestive heart failure, either systemic venous congestion or pulmonary edema. Other common initial symptoms of restrictive cardiomyopathy in children include failure to thrive, fatigue and syncope.3 Our patient was diagnosed at 1.5 years of age and, aside from nonspecific symptoms, was unusual in having only abdominal distension. Restrictive cardiomyopathy accounts for only approximately 2−5% of all pediatric cardiomyopathies.2,4 Because the number of reported patients is so small,1,2 findings in adult disease are often extrapolated to guide clinical evaluation and management of pediatric patients. There are, however, some important differences. Adults with idiopathic restrictive cardiomyopathy have a relatively prolonged course and reasonably good 5-year survival.5,6 However, in the two reported pediatric series
S.M. Lin et al mentioned above, the average 2-year survival was < 50% from the time of diagnosis.1,2 This difference in survival rate may be due to delayed detection of the disease in children who already have overt congestive heart failure when they present, in contrast to adults, who tend to be diagnosed earlier. The diagnostic criteria for restrictive cardiomyopathy are: (1) marked biatrial dilatation; (2) normal LV chamber size and LV ejection fraction > 50%; (3) LV end-diastolic pressure > 15 mmHg; and (4) LV end-diastolic pressure at least 5 mmHg greater than RV end-diastolic pressure.1 Doppler study reveals diastolic dysfunction consistent with restrictive physiology, namely the typical square root sign. Our patient’s findings were completely compatible with this diagnosis, and she had no evidence of pericardial thickening that would suggest constrictive pericarditis.7 She did not yet have significant pulmonary hypertension at the time of diagnosis because of early detection. Other entities to be considered that may reduce ventricular diastolic compliance include specific infiltrative disorders of the myocardium such as glycogen storage disease, mucopolysaccharidosis, hemochromatosis, amyloidosis, sarcoidosis, and endomyocardial fibrosis.5,8 Our patient’s absence of multiorgan involvement, a history not suggestive of such disease, and the cardiac MRI helped to exclude these possibilities, although we did not do endomyocardial biopsy to rule them out completely. Pediatric restrictive cardiomyopathy carries a high risk for rapidly progressive elevation in pulmonary vascular resistance9 and for sudden death.10 Poor prognostic factors that have been identified include cardiomegaly, age < 5 years, thromboembolism, pulmonary venous congestion, syncope, or chest pain at diagnosis.10,11 An increased echocardiographic LA to Ao ratio at initial presentation is also a strong predictor of poor outcome.3 Because of the poor prognosis of this disease, it is recommended that children with restrictive cardiomyopathy be given preferential status on cardiac transplant waiting lists.10 Our patient’s young age and increased LA to Ao ratio put her at high risk, and she is therefore listed for a cardiac transplant.
References 1.
2. 3. 4.
Kimberling MT, Balzer DT, Hirsch R, et al. Cardiac transplantation for pediatric restrictive cardiomyopathy: presentation, evaluation, and short-term outcome. J Heart Lung Transplant 2002;21:455−9. Lewis AB. Clinical profile and outcome of restrictive cardiomyopathy in children. Am Heart J 1992;123:1589−93. Russo LM, Webber SA. Idiopathic restrictive cardiomyopathy in children. Heart 2005;91:1199−202. Towbin JA. Cardiomyopathies. In: Moller JH, Hoffman JI, eds. Pediatric Cardiovascular Medicine. New York: Churchill Livingstone, 2000:753−67.
Restrictive cardiomyopathy 5. 6. 7.
8.
Benotti JR, Grossman W, Cohn PF. Clinical profile of restrictive cardiomyopathy. Circulation 1980;61:1206−12. Siegel RJ, Shah PK, Fishbein MC. Idiopathic restrictive cardiomyopathy. Circulation 1984;70:165−9. Goldstein JA. Differentiation of constrictive pericarditis and restrictive cardiomyopathy. In: ACC Educational Highlights. Anaheim, California, 1997:14−22. Abelmann WH, Lorell BH. The challenge of cardiomyopathy. J Am Coll Cardiol 1989;13:1219−39.
51 9.
Denfield SW, Rosenthal G, Gajarski RJ, et al. Restrictive cardiomyopathies in childhood. Etiologies and natural history. Tex Heart Inst J 1997;24:38−44. 10. Rivenes SM, Kearney DL, Smith EO, et al. Sudden death and cardiovascular collapse in children with restrictive cardiomyopathy. Circulation 2000;102:876−82. 11. Chen SC, Balfour IC, Jureidini S. Clinical spectrum of restrictive cardiomyopathy in children. J Heart Lung Transplant 2001;20:90−2.