Atrial flutter in fetuses and early childhood: a report of eight cases.

Atrial flutter is an uncommon arrhythmia in children. The presenting features and treatment responses of two fetuses and six children with atrial flutter were presented. Two patients were diagnosed prenatally at 31 and 35 weeks' gestation. One patient was successfully controlled in utero by maternal administration of digoxin and the other by direct current cardioversion after delivery. Two fetuses and 2 of 6 children had normal cardiac structure by echocardiogram. Three patients had right atrial enlargement due to atrial primun septal defect, secundum atrial septal defect with primary pulmonary hypertension, and endomyocardial fibrosis. One patient developed atrial flutter with sinus node dysfunction after surgical correction of total anomalous pulmonary venous connection. Four cases presented as atrial flutter with regular atrioventricular conduction (2:1 or 3:1 conduction) while the remainder presented with irregular atrioventricular conduction. Heart failure was presented in two patients and improved after the arrhythmias were controlled. Successful termination of atrial flutter was accomplished by using DC cardioversion in 4 patients and one patient converted to normal sinus rhythm following combination of digoxin and amiodarone administration. Digoxin was administered for one year as the prophylactic medication in six patients. None had recurrence of atrial flutter during the follow-up period of one to four years. Two patients required chronic digoxin and amiodarone therapy. We concluded that atrial flutter in fetuses and early childhood carries a good prognosis. Acute treatment with direct current cardioversion is sufficient in most patients, combination of digoxin and amiodarone may be an alternative therapy to convert atrial flutter.

Cardiac dysfunction in beta-thalassemic children.

The biventricular systolic function was evaluated by M mode and Doppler echocardiography in 16 patients with homozygous beta-thalassemia and beta-thalassemia Hb E disease, aged 5-14 yrs (9.9 +/- 2.4 yr). The left ventricular end-diastolic dimension and left ventricular mass were increased in 88 per cent of the patients. Left ventricular fractional shortening and cardiac index were normal in all but one patient. Fifteen patients had evidence of pulmonary artery hypertension manifested by abnormality in the ratio of right ventricular acceleration time to ejection time (AT/ET). There was good correlation between platelets count and AT/ET (r = -0.70, P = 0.002). Thrombocytosis was noted in 4 patients. Our findings indicated that in beta-thalassemic children, right ventricular dysfunction was detected earlier than left ventricular dysfunction and platelets may play a role in the pathogenesis of pulmonary artery hypertension.

Doppler echocardiographic predictions of pulmonary artery pressure in children with congenital heart disease.

Continuous wave Doppler echocardiography was used to examine the accuracy of predictions of pulmonary artery pressure by means of main pulmonary artery flow velocity in children with congenital heart disease, without pulmonary stenosis. The ratio of acceleration time to ejection time (AT/ET) was correlated to catheterized mean pulmonary artery pressure. The result was: mean pulmonary pressure equal to 120-2.4 (AT/ET x 100), r = 0.92, SEE = 7.9 mmHg, P value less than 10(-6). We then used this equation prospectively to predict mean pulmonary artery pressure in 20 children. The result was: catheterized mean pulmonary artery pressure equal to 0.9 predicted pressure minus 0.3, r = 0.94, SEE = 4.8 mmHg, 95 per cent confidence limit interval of X coefficient was 0.8 to 1.2. This result suggested that continuous wave Doppler predictions of pulmonary artery pressure correlate significantly with values subsequently obtained at catheterization.