10 0 4
Editorial correspondence
thimide and circulating 1,25-dihydroxyvitamin D in vitamin D intoxication. Br Med J 1988;297:902-4. 4. Cadranel J, Hance A J, Milleron B, Paillard F, Akoun GM, Garabedian M. Vitamin D metabolism in tuberculosis: production of 1,25(OH)2D3 by cells recovered by bronchoalveolar lavage and the role of this metabolite in calcium homeostasis. Am Rev Respir Dis 1988;138:984-9.
Thyroid function after prolonged treatment for congenital
hypothyroidism To the Editor: L6ger and Czernichow (J PEDIATR 1990;116:411-4) recently reported the persistence of thyroid secretion in patients with congenital hypothyroidism with ectopic glands, as assessed by the presence of circulating thyroglobulin, even after prolonged substitutive therapy with L-thyroxine (L-T4). We also have studied the function of remnant thyroid tissue in children with congenital hypothyroidism treated with L-T4 for a long period. Thyroid scans were obtained for 23 children whose condition was diagnosed by a mass screening program: 15 scans at the time of diagnosis, before the start of L-T4 therapy (27 _+ 8 days; range 17 to 41; median 27), and eight scans after a variable period of substitutive therapy (7.1 _+ 3.5 years; range 1.3 to 12.8; median 7.4). In the first group of patients we found six examples of thyroid agenesis (40%), four ectopic glands (26.7%), and five thyroid glands in situ (33.3%); in the second group were five examples of agenesis (62.5%), two ectopic glands (25%), and one thyroid gland in situ (12.5%). The Fisher Exact Test showed no statistical difference between groups. The evaluation of thyroid hormones (triiodothyronine [T3], T4, reverse T3, free T3, free T4), after a brief withdrawal of L-T4 therapy, in patients with thyroid ectopia, demonstrated the persistence of thyroid secretion, even after a long period of substitutive therapy, with a wide range of function as reported by others. 1 This finding, together with the observation that the relative percentage of thyroid ectopia did not change after a long period of therapy, demonstrates that the remnant tissue is still functional and that it does not become totally involuted, as reported by others. 2 We conclude that prolonged substitutive therapy with L-T4 does not completely suppress the remnant thyroid tissue and that the thyroid scan, even if obtained after a long period of L-T4 therapy, permits one to make the correct etiologic diagnosis. Luciano Cavallo, MD Nieola Laforgia, MD Teresa De Bellis. MD Battista De Luea, MD Marino Mele, MD Istituto di Pediatria Clinica e Preventiva Cattedra di Medicina Nucleare University of Bari Policlinico, Piazza G. Cesare 70124 Bari, Italy
The Journal of Pediatrics December 1990
REFERENCES
1. Grant DB, Hulse JA, Jackson DB, Leung SP, Ng WK. Ectopic thyroid: residual function after withdrawal of treatment in infancy and later childhood. Acta Paediatr Scand 1989;78:88992. 2. Job JC, Canlorbe P, Tubiana M. Decreasing radioiodine uptake during the course of congenital hypothyroidism. In: Cassan C, Andreali M, eds. Current topics in thyroid research. New York: Academic Press, 1965:827-31.
Reply To the Editor: We entirely agree with this letter except for the final conclusion. We have demonstrated that in patients with an ectopic gland, thyroglobulin increases after a brief period of withdrawal of substitutive therapy. A simple venipuncture and a thyroglobutin measurement permit a correct diagnosis. There is no need for a thyroid scan, which is more expensive, time-consuming, and not always available. J. L~ger, MD P. Czernichow, MD HSpital Robert Debrb 48, bvd Sbrurier 75019 Paris, France
Indications for aortocoronary bypass surgery after Kawasaki disease To the Editor." Two similar articles with regard to aortocoronary bypass surgery (ACBS) in the treatment of Kawasaki disease have recently been published in this JOURNAL (J P~DIATR 1990;116:567-73) and in another journal. I In both articles, angiographic studies after ACBS revealed excellent long-term patency of internal mammary artery grafts. In this JOURNAL, Suzuki et al. attempted to establish indications for ACBS by retrospective analysis of 26 patients with Kawasaki disease. We generally agree with their proposed indications for ACBS. However, these indications appear to be somewhat restrictive. The authors had 75 patients with severe stenotic lesions of the right and/or left coronary artery. Of the 75 patients, 42 had not undergone ACBS because of brain damage, percutaneous transluminal coronary angioplasty (PTCA), and so on. Of these 42 patients who had not undergone ACBS, 28 had severe stenosis of the right coronary artery only. Three patients had native coronary arteries too small for connection with a graft. The authors did not describe the outcome of either of these groups. Furthermore, the cause of death of seven patients who died before ACBS in their series was not described. Did any patients die of occlusion of right coronary artery? I wonder whether the severe stenosis of the right coronary artery only is not an indication for ACBS. The determination of such indications is probably derived from the authors' studies regarding the natural history of Coronary arterial lesions. 2 However, occlusion of the right coronary artery may induce not only inferior infarction of the left ventricle but also right ventric-
Volume 117 Number 6
Editorial correspondence
ular infarction and fatal heart block, although the size of the infarction is influenced by coronary artery dominance. 3 The mortality rate is not low. We recently reported a 31 -month-old boy who had had a severe stenosis of the right coronary artery after Kawasaki disease and had successfully undergone P T C A . 4 Follow-up angiography 6 months later revealed no evidence of restenosis. In a small child with Kawasaki disease, P T C A m a y have a potential advantage as a temporary method to postpone the ACBS, although the safety of P T C A has not yet been established. Suzuki et al. also described a patient who had undergone P T C A . Which coronary artery was dilated? W h a t was the outcome in this patient? The detailed data on this patient may be clinically important. We believe that P T C A m a y be safe and useful if the stenosis is not segmental but is localized at the right coronary artery. Thus, if P T C A can be used for significant coronary artery stenosis in Kawasaki disease, the indications for ACBS may be changed, as they have been in adults.
Toshihiro Ino, MD Shinjiro Shimazaki, MD Kei Nishimoto, MD Masazumi lwahara, MD Keijiro Yabuta, MD Department of Pediatrics Juntendo University School of Medicine 2-1-1 Hongo, Bunkyo-Ku Tokyo 113, Japan REFERENCES
1. Kitamura S, Kawachi K, Seki T, et al. Bilateral internal m a m m a r y artery grafts for coronary artery bypass operations in children. J Thorac Cardiovasc Surg 1990;99:708-15. 2. Suzuki A, Kamiya T, O n e Y, Kohata T, Kimura K, Takamiya M. Follow-up study of coronary artery lesion due to Kawasaki disease by serial selective coronary arteriography in 200 patients. Heart Vessels 1987;3:159-65. 3. Berger PB, Ryan TJ. Inferior myocardial infarction: high-risk subgroups. Circulation 1990;81:401-11. 4. Ino T, Nishimoto K, Akimoto K, et al. Percutaneous transluminal coronary angioplasty for Kawasaki disease: a case report and literature review. Pediatr Cardiol (in press).
Reply To the Editor." Dr. lno and colleagues raise a point of considerable interest. I believe that PTCA may well be indicated for a severe localized stenosis of the right coronary artery. A m o n g our seven deceased patients, a 1-year-old boy died suddenly because of occlusion of the right coronary artery. The autopsy showed evidence of acute myocardial infarction at the site of the conduction system. Another patient died during a P T C A procedure performed for a 90% localized stenosis of the left anterior descending artery. The remaining five patients died because of occlusion of the left coronary artery; three of the five had had right coronary arterial occlusions. Among the 75 patients, 54 had severe stenotic lesions of the rigtit coronary artery or both coronary arteries. However, at the time of occlusion of the right coronary artery, only one patient with a
10 0 5
dominant right coronary artery and a hypoplastic circumflex artery had significant symptoms of myocardial infarction. Later, this occlusion recanalized and changed to what we call segmental stenosis, and the performance of the left and right ventricles recovered completely. In our 28 patients with stenotic lesions of the right coronary artery alone, 15 patients had occlusion, 6 had segmental stenosis, and 7 had ~ 75% localized stenosis. However, in 13 of the 15 occlusions, development of segmental stenosis was demonstrated on the subsequent angiographic examination. In general, occlusions of the right coronary artery have a tendency to recanalize, ~' 2 and this natural course of right coronary arterial lesion r e s u l t s in remarkable recovery from myocardial ischemia. 3 Another reason that we do not consider bypass surgery for severe stenoses of the right coronary artery is that these stenoses usually appear within short periods after the acute phase of Kawasaki disease, and they change into segmental stenosis rapidly, l' z On the contrary, severe localized stenosis of the left coronary artery usually appears several years after the disease. 2 Until that time, internal m a m m a r y arteries should be kept intact for the surgery. Percutaneous angioplasty for stenotic lesions of the right coronary artery may well be useful if it is feasible, even in very young children, as in the patient reported by Ino. With respect to our experience with PTCA, of two patients, one died during the procedure and the other underwent P T C A for a 90% localized stenosis of the left anterior descending artery on two separate occasions; there was no effect, and the patient underwent aortocoronary bypass surgery subsequently. Thus, P T C A seems to be ineffective in a gradually progressing localized stenosis of the left coronary artery. Probably a stenotic lesion of the right coronary artery in the early phase after Kawasaki disease is primarily due to formation of a massive thrombus in an aneurysm, whereas progressive stenosis of the left coronary artery is secondary to intimal proliferation4; P T C A may be more effective in the former than in the latter. The three patients whose native coronary artery with a proximal occlusion was considered too small for aortocoronary bypass surgery are doing well, with no significant clinical symptoms of myocardial infarction, although their activities are slightly restricted. There has been no growth of the coronary artery distal to the occlusion, and we do not believe them to be candidates for aortocoronary bypass surgery. Our indications for aortocoronary bypass surgery could be too restrictive. However, the results of the surgery are far from being perfect at present, and the coronary arterial lesions are sometimes progressive even after surgery. Therefore 1 believe that the arteries that can be used for grafting should be saved for eventual bypass surgery if possible, rather than using them for bypass surgery performed too early on the basis of a somewhat equivocal indication.
Atsuko Suzuki, MD Department of Pediatrics National Cardiovascular Center Osaka 565, Japan
REFERENCES
1. Suzuki A, Kamiya T, Ono Y, et al. Follow-up study of coronary artery lesions due to Kawasaki disease by serial selective
Editorial correspondence
thimide and circulating 1,25-dihydroxyvitamin D in vitamin D intoxication. Br Med J 1988;297:902-4. 4. Cadranel J, Hance A J, Milleron B, Paillard F, Akoun GM, Garabedian M. Vitamin D metabolism in tuberculosis: production of 1,25(OH)2D3 by cells recovered by bronchoalveolar lavage and the role of this metabolite in calcium homeostasis. Am Rev Respir Dis 1988;138:984-9.
Thyroid function after prolonged treatment for congenital
hypothyroidism To the Editor: L6ger and Czernichow (J PEDIATR 1990;116:411-4) recently reported the persistence of thyroid secretion in patients with congenital hypothyroidism with ectopic glands, as assessed by the presence of circulating thyroglobulin, even after prolonged substitutive therapy with L-thyroxine (L-T4). We also have studied the function of remnant thyroid tissue in children with congenital hypothyroidism treated with L-T4 for a long period. Thyroid scans were obtained for 23 children whose condition was diagnosed by a mass screening program: 15 scans at the time of diagnosis, before the start of L-T4 therapy (27 _+ 8 days; range 17 to 41; median 27), and eight scans after a variable period of substitutive therapy (7.1 _+ 3.5 years; range 1.3 to 12.8; median 7.4). In the first group of patients we found six examples of thyroid agenesis (40%), four ectopic glands (26.7%), and five thyroid glands in situ (33.3%); in the second group were five examples of agenesis (62.5%), two ectopic glands (25%), and one thyroid gland in situ (12.5%). The Fisher Exact Test showed no statistical difference between groups. The evaluation of thyroid hormones (triiodothyronine [T3], T4, reverse T3, free T3, free T4), after a brief withdrawal of L-T4 therapy, in patients with thyroid ectopia, demonstrated the persistence of thyroid secretion, even after a long period of substitutive therapy, with a wide range of function as reported by others. 1 This finding, together with the observation that the relative percentage of thyroid ectopia did not change after a long period of therapy, demonstrates that the remnant tissue is still functional and that it does not become totally involuted, as reported by others. 2 We conclude that prolonged substitutive therapy with L-T4 does not completely suppress the remnant thyroid tissue and that the thyroid scan, even if obtained after a long period of L-T4 therapy, permits one to make the correct etiologic diagnosis. Luciano Cavallo, MD Nieola Laforgia, MD Teresa De Bellis. MD Battista De Luea, MD Marino Mele, MD Istituto di Pediatria Clinica e Preventiva Cattedra di Medicina Nucleare University of Bari Policlinico, Piazza G. Cesare 70124 Bari, Italy
The Journal of Pediatrics December 1990
REFERENCES
1. Grant DB, Hulse JA, Jackson DB, Leung SP, Ng WK. Ectopic thyroid: residual function after withdrawal of treatment in infancy and later childhood. Acta Paediatr Scand 1989;78:88992. 2. Job JC, Canlorbe P, Tubiana M. Decreasing radioiodine uptake during the course of congenital hypothyroidism. In: Cassan C, Andreali M, eds. Current topics in thyroid research. New York: Academic Press, 1965:827-31.
Reply To the Editor: We entirely agree with this letter except for the final conclusion. We have demonstrated that in patients with an ectopic gland, thyroglobulin increases after a brief period of withdrawal of substitutive therapy. A simple venipuncture and a thyroglobutin measurement permit a correct diagnosis. There is no need for a thyroid scan, which is more expensive, time-consuming, and not always available. J. L~ger, MD P. Czernichow, MD HSpital Robert Debrb 48, bvd Sbrurier 75019 Paris, France
Indications for aortocoronary bypass surgery after Kawasaki disease To the Editor." Two similar articles with regard to aortocoronary bypass surgery (ACBS) in the treatment of Kawasaki disease have recently been published in this JOURNAL (J P~DIATR 1990;116:567-73) and in another journal. I In both articles, angiographic studies after ACBS revealed excellent long-term patency of internal mammary artery grafts. In this JOURNAL, Suzuki et al. attempted to establish indications for ACBS by retrospective analysis of 26 patients with Kawasaki disease. We generally agree with their proposed indications for ACBS. However, these indications appear to be somewhat restrictive. The authors had 75 patients with severe stenotic lesions of the right and/or left coronary artery. Of the 75 patients, 42 had not undergone ACBS because of brain damage, percutaneous transluminal coronary angioplasty (PTCA), and so on. Of these 42 patients who had not undergone ACBS, 28 had severe stenosis of the right coronary artery only. Three patients had native coronary arteries too small for connection with a graft. The authors did not describe the outcome of either of these groups. Furthermore, the cause of death of seven patients who died before ACBS in their series was not described. Did any patients die of occlusion of right coronary artery? I wonder whether the severe stenosis of the right coronary artery only is not an indication for ACBS. The determination of such indications is probably derived from the authors' studies regarding the natural history of Coronary arterial lesions. 2 However, occlusion of the right coronary artery may induce not only inferior infarction of the left ventricle but also right ventric-
Volume 117 Number 6
Editorial correspondence
ular infarction and fatal heart block, although the size of the infarction is influenced by coronary artery dominance. 3 The mortality rate is not low. We recently reported a 31 -month-old boy who had had a severe stenosis of the right coronary artery after Kawasaki disease and had successfully undergone P T C A . 4 Follow-up angiography 6 months later revealed no evidence of restenosis. In a small child with Kawasaki disease, P T C A m a y have a potential advantage as a temporary method to postpone the ACBS, although the safety of P T C A has not yet been established. Suzuki et al. also described a patient who had undergone P T C A . Which coronary artery was dilated? W h a t was the outcome in this patient? The detailed data on this patient may be clinically important. We believe that P T C A m a y be safe and useful if the stenosis is not segmental but is localized at the right coronary artery. Thus, if P T C A can be used for significant coronary artery stenosis in Kawasaki disease, the indications for ACBS may be changed, as they have been in adults.
Toshihiro Ino, MD Shinjiro Shimazaki, MD Kei Nishimoto, MD Masazumi lwahara, MD Keijiro Yabuta, MD Department of Pediatrics Juntendo University School of Medicine 2-1-1 Hongo, Bunkyo-Ku Tokyo 113, Japan REFERENCES
1. Kitamura S, Kawachi K, Seki T, et al. Bilateral internal m a m m a r y artery grafts for coronary artery bypass operations in children. J Thorac Cardiovasc Surg 1990;99:708-15. 2. Suzuki A, Kamiya T, O n e Y, Kohata T, Kimura K, Takamiya M. Follow-up study of coronary artery lesion due to Kawasaki disease by serial selective coronary arteriography in 200 patients. Heart Vessels 1987;3:159-65. 3. Berger PB, Ryan TJ. Inferior myocardial infarction: high-risk subgroups. Circulation 1990;81:401-11. 4. Ino T, Nishimoto K, Akimoto K, et al. Percutaneous transluminal coronary angioplasty for Kawasaki disease: a case report and literature review. Pediatr Cardiol (in press).
Reply To the Editor." Dr. lno and colleagues raise a point of considerable interest. I believe that PTCA may well be indicated for a severe localized stenosis of the right coronary artery. A m o n g our seven deceased patients, a 1-year-old boy died suddenly because of occlusion of the right coronary artery. The autopsy showed evidence of acute myocardial infarction at the site of the conduction system. Another patient died during a P T C A procedure performed for a 90% localized stenosis of the left anterior descending artery. The remaining five patients died because of occlusion of the left coronary artery; three of the five had had right coronary arterial occlusions. Among the 75 patients, 54 had severe stenotic lesions of the rigtit coronary artery or both coronary arteries. However, at the time of occlusion of the right coronary artery, only one patient with a
10 0 5
dominant right coronary artery and a hypoplastic circumflex artery had significant symptoms of myocardial infarction. Later, this occlusion recanalized and changed to what we call segmental stenosis, and the performance of the left and right ventricles recovered completely. In our 28 patients with stenotic lesions of the right coronary artery alone, 15 patients had occlusion, 6 had segmental stenosis, and 7 had ~ 75% localized stenosis. However, in 13 of the 15 occlusions, development of segmental stenosis was demonstrated on the subsequent angiographic examination. In general, occlusions of the right coronary artery have a tendency to recanalize, ~' 2 and this natural course of right coronary arterial lesion r e s u l t s in remarkable recovery from myocardial ischemia. 3 Another reason that we do not consider bypass surgery for severe stenoses of the right coronary artery is that these stenoses usually appear within short periods after the acute phase of Kawasaki disease, and they change into segmental stenosis rapidly, l' z On the contrary, severe localized stenosis of the left coronary artery usually appears several years after the disease. 2 Until that time, internal m a m m a r y arteries should be kept intact for the surgery. Percutaneous angioplasty for stenotic lesions of the right coronary artery may well be useful if it is feasible, even in very young children, as in the patient reported by Ino. With respect to our experience with PTCA, of two patients, one died during the procedure and the other underwent P T C A for a 90% localized stenosis of the left anterior descending artery on two separate occasions; there was no effect, and the patient underwent aortocoronary bypass surgery subsequently. Thus, P T C A seems to be ineffective in a gradually progressing localized stenosis of the left coronary artery. Probably a stenotic lesion of the right coronary artery in the early phase after Kawasaki disease is primarily due to formation of a massive thrombus in an aneurysm, whereas progressive stenosis of the left coronary artery is secondary to intimal proliferation4; P T C A may be more effective in the former than in the latter. The three patients whose native coronary artery with a proximal occlusion was considered too small for aortocoronary bypass surgery are doing well, with no significant clinical symptoms of myocardial infarction, although their activities are slightly restricted. There has been no growth of the coronary artery distal to the occlusion, and we do not believe them to be candidates for aortocoronary bypass surgery. Our indications for aortocoronary bypass surgery could be too restrictive. However, the results of the surgery are far from being perfect at present, and the coronary arterial lesions are sometimes progressive even after surgery. Therefore 1 believe that the arteries that can be used for grafting should be saved for eventual bypass surgery if possible, rather than using them for bypass surgery performed too early on the basis of a somewhat equivocal indication.
Atsuko Suzuki, MD Department of Pediatrics National Cardiovascular Center Osaka 565, Japan
REFERENCES
1. Suzuki A, Kamiya T, Ono Y, et al. Follow-up study of coronary artery lesions due to Kawasaki disease by serial selective
