Richard M. Donner

Ectopic automatic atrial tachycardia in children: Clinical characteristics, management and follow-up

Ectopic automatic atrial tachycardia, an uncommon type of supraventricular tachycardia in children and adults, has been reported to be resistant to medical therapy, and surgical or cryoblation has been recommended. This report describes 10 infants and children (median age 6 months; range birth to 7.5 years) with automatic atrial tachycardia and their management and follow-up. Digoxin alone was unsuccessful in controlling tachycardia in all 10 patients but decreased the tachycardia rate by 5 to 20% in 8. Intravenous (0.1 mg/kg body weight per dose) and oral propranolol successfully suppressed tachycardia in three of five patients and oral propranolol successfully controlled tachycardia in two of five other patients. Class I antiarrhythmic agents--quinidine (three patients), procainamide (four patients) and phenytoin (three patients)--did not control tachycardia in any patients but made the tachycardia rate worse in three patients. Intravenous (5 mg/kg per dose) and oral amiodarone suppressed tachycardia in three of four patients and oral amiodarone suppressed it in another patient. Thus, intravenous propranolol and amiodarone were effective in acutely suppressing automatic ectopic atrial tachycardia and predicted the response to long-term oral therapy. One patient had persistent tachycardia after surgical ablation of the high right atrial ectopic focus, and another patient had unsuccessful catheter ablation of the high right atrial ectopic focus (25 J). During follow-up (10 to 28 months), ectopic atrial tachycardia resolved completely in four patients and was well controlled in four patients.

Left ventricular wall stress in compensated aortic stenosis in children

It is known that children with aortic stenosis (AS) frequently have supernormal indexes of left ventricular (LV) pump function and remain compensated for many years. Factors causing this increase in pump performance have not been elucidated. A study was done on LV mechanics in 11 children with AS (aortic valve area 0.5 +/- 0.3 cm2/m2) and 10 normal subjects. The ejection fraction in the AS group (0.88 +/- 0.08) was significantly higher than in normal subjects (0.64 +/- 0.08, p less than 0.001). The mean velocity of fiber shortening was also higher in AS patients (1.80 +/- 0.35 circ/s) than in normal subjects (1.22 +/- 0.21 circ/s, p less than 0.001). The end-systolic volume index in patients with AS (9 +/- 8 ml/m2) was much lower than in normal subjects (27 +/- 8 ml/m2). LV mass in patients with AS was 180 +/- 58 g/m2 compared with 96 +/- 9 in normal subjects. LV wall stress was reduced throughout the cardiac cycle in patients with AS. Peak stress in patients with AS was 238 +/- 51 dynes/cm2 X 10(3) versus 439 +/- 85 in normal subjects. The end-systolic stress-end-systolic volume index ratio, an indicator of contractile state, was not elevated in patients with AS. It is suggested that diminished wall stress in concert with normal contractile function permits the supernormal pump function seen at rest in children with AS.

Sudden Death in Childhood Due to Right Ventricular Dysplasia: Report of Two Cases

Two cases of sudden death due to arrhythmogenic right ventricular dysplasia (ARVD) occurring in the pediatric age group are described. One of the subjects, at the age of 7 years, is believed to be the youngest child in whom ARVD has been diagnosed at autopsy. The clinical and pathological characteristics of ARVD are discussed.

Polysplenia and Kartagener syndromes in a sibship: Association with abnormal respiratory cilia

1. Chandra RS: Biliary atresia and other structural anomalies in the congenital polysplenia syndrome, J PEO~ATR 85:649, 1974. 2. Dimmick VE, Bone KE, and McAdames A J: Extrahepatic biliary atresia and the polysplenia syndrome, J PEDIATR 86:644, 1975. 3. Eliasson R, Mossberg, B, Camner P, and Afzelius B: The immotile cilia syndrome, N Engl J Med 297:1, 1977. 4. Afzelius A: A human syndrome caused by immotile cilia, Science 193:317, 1976. 5. Schidlow DV, Moriber Katz S, Turtz MG, Donner RM, and Capasso S: Polysplenia and Kartagener syndromes in a sibship: Association with abnormal respiratory cilia, J PEDIATR 100:401, 1982. 6, Rooklin AR, McGeady S J,. Mikaelin DO, Soriano RZ, and Mansmann HC: The immotile cilia syndrome: a case of recurrent pulmonary disease in children, Pediatrics 66:526, 1980. 7. Sturgess JM, Chao J, Wong J, Aspin N, and Turner UAP: Cilia with defective radial spokes. A cause of human respiratory disease, N Eng[ J Med 300:53, 1979. 8. Sturgcss JM, Chao J, and Turner JAP: Transposition of ciliary microtubules. Another cause of impaired ciliary motility, N Engl J Med 303:318, 1980. 9. Fawcett D: What makes cilia and sperm tails beat? N Engl J Med 297:46, 1979. 10. Alagille D, and Odieore M: Liver and biliary tract disease in children, New York, 1979, John Wiley, & Sons, Inc.

Variant angina in an 11 year old boy

Variant angina is a syndrome in which ischemic cardiac pain occurs with ST segment elevation. The syndrome is due at least in part to coronary vasospasm. Although well documented in adults, there are no known reports of this syndrome in children. The clinical, electrocardiographic and echocardiographic findings in an 11 year old boy with variant angina are reported.

Dilatation of the descending aorta: a radiologic and echocardiographic diagnostic sign in arteriovenous malformations in neonates and young infants

Eleven infants with arteriovenous malformations were admitted to St. Christophers Hospital for Children between 1970 and 1978. Dilatation of the descending aorta was seen in the chest roentgenogram in 8 of the 11 patients. Echocardiography used in the two most recent cases revealed approximation of the descending aorta to the posterior left atrial and left ventricular wall in association with generalized cardiomegaly. The most frequently reported radiologic findings in infants with arteriovenous malformations are cardiomegaly, increased pulmonary vasculature and a widened superior mediastinum. These findings can accompany other congenital malformations of the heart, but the radiographic and echocardiographic findings of a dilated descending aorta appear to be more specifically associated with arteriovenous malformations in the neonate and infant.

Left ventricular wall stress and function in childhood coarctation of the aorta

Unlike most adults with compensated pressure overload of the left ventricle, children with moderate to severe aortic stenosis exhibit pronounced left ventricular muscle hypertrophy, enhanced ejection performance and diminished wall stress. To determine whether these findings are present in other forms of left ventricular pressure overload in children, left ventricular mechanics were studied by catheterization in 14 children with coarctation of the aorta (average peak gradient 39 +/- 17 mm Hg) and in 10 normal children. Ejection fraction and mean velocity of circumferential fiber shortening in the coarctation group (0.74 +/- 0.09 and 1.71 +/- 0.43 circumferences/s, respectively) were significantly higher than in normal subjects (0.65 +/- 0.05 and 1.27 +/- 0.26 circumferences/s, respectively) (p = 0.008), but the ranges for both groups overlapped. End-systolic stress in children with coarctation (77 +/- 20 dynes X 10(3)/cm2) was less than in normal children (121 +/- 24 dynes X 10(3)/cm2) (p less than 0.001), again with overlap of the ranges for both groups. The ratio of end-systolic stress to end-systolic volume index, an estimate of contractile function, was similar in both groups. Relations between severity of obstruction (left ventricular peak systolic pressure, coarctation gradient) and end-systolic stress and between stress and ejection performance were present within the coarctation group. Comparison of these data with those found in children with moderate to severe aortic stenosis shows a similar but less pronounced response to pressure overload due to coarctation of the aorta.

Improved prediction of peak left ventricular pressure by echocardiography in children with aortic stenosis

Prediction of peak left ventricular pressure by echocardiography in children with aortic stenosis assumes that wall stress is normal. The recent finding that stress is subnormal in many children with aortic stenosis and elevated ejection performance requires reevaluation of this noninvasive technique. By using M-mode echocardiography, left ventricular end-diastolic dimension and wall thickness and left ventricular shortening fraction were measured in 27 children with aortic stenosis undergoing left ventricular pressure measurement by cardiac catheterization. Similar echocardiographic measurements and systolic blood pressure determinations by the cuff method were obtained from 29 normal children. Peak circumferential wall stress and shortening fraction were calculated from the echocardiographic and pressure data. It was found that stress was inversely proportional to shortening fraction for all patients with aortic stenosis (p less than 0.001, r = -0.86). In a subgroup of patients with a shortening fraction of less than 0.40, stress was 262 +/- 20 mm Hg, similar to 280 +/- 30 mm Hg in the normal group but greater than 205 +/- 27 mm Hg in patients with a shortening fraction of 0.40 or greater (p less than 0.001). In patients with aortic stenosis, the ratio of left ventricular end-diastolic wall thickness to cavity dimension predicted peak left ventricular pressure moderately well (r = 0.83, standard error of the estimate [SEE] = 23). The stress-shortening fraction relation was used to estimate stress and correct this ratio in patients with diminished stress and a shortening fraction greater than or equal to 0.40. This yielded a significantly improved correlation (r = 0.93, SEE = 15, p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Cerebral rhinocele, hydrocephalus, and cleft lip and palate in infants with cardiac fibroma.

Cardiac transplantation was performed in two infants with unresectable fibromas of the myocardium. In one patient, lip surgery was also required for unilateral cleft lip and palate. At autopsy, communicating hydrocephalus of mild to moderate degree was found in both cases. In the patient with facial clefts, there was also a large, ipsilateral cyst, or rhinocele, of the olfactory lobe. This unusual lesion, which seems to represent a previously unreported malformation, was apparently formed by segmental dilatation of a persistent olfactory ventricle. Cerebral or cranial anomalies are thought to be rare in cases of cardiac fibroma; however, macrocephaly was present in five patients. Furthermore, presenting abnormalities among previously reported cases included hydrocephalus in one case, and cleft lip and palate in another. These and other findings suggest that, at least in some cases, cardiac fibroma is a manifestation of a more extensive developmental disorder.