Atrial tachyarrhythmias in infants

This report describes clinical features and tactics of treatment of atrial tachyarrhythmias in infancy. Electrophysiologic study was performed in all 20 infants (2 weeks - 12 months old) in order to determine the mechanism of arrhythmia and to predict the clinical efficacy of management. Reciprocating mechanism was revealed in 12 infants. Atrial flutter was diagnosed for 10 infants among whom only 2 patients were older than two months. Six infants were found to have flutter conduction with a rate of 1:1. Four infants had congestive heart failure, 3 of them with a structurally normal heart. Half of the infants with atrial flutter needed long-term antiarrhythmic therapy. Electrotherapy for termination of atrial flutter was effective in all of them. Automatic atrial tachycardia in eight infants presented no major problems unless it became incessant and resistant to pharmacological treatment. The average tachycardia rate reached 171+/-7 beats/min. Atrial reciprocating tachycardia usually affects patients with diseased myocardium.     

Left Atrial Appendectomy After Failed Catheter Ablation of a Focal Atrial Tachycardia Originating in the Left Atrial Appendage

This report describes a case of left atrial appendectomy after a failed endocardial catheter ablation of a continuous drug-refractory left atrial appendage (LAA) tachycardia in a 9-year-old boy. Electrophysiologic study showed atrial tachycardia (AT) originating in the LAA. Numerous radiofrequency applications with an irrigated-tip catheter were ineffective. During surgery, direct pressure on the apex of the LAA by forceps immediately terminated the AT and restored sinus rhythm. After a left atrial appendectomy, the patient remained free of any arrhythmias during a follow-up period of 18 months.     

Atrial septal aneurysm in infancy

Summary Thirteen infants were found to have atrial septal aneurysms (ASAs) on twodimensional (2D) echocardiography and their characteristics and natural course have been studied by 2D Doppler echocardiography.Atrial septal aneurysm was accompanied by atrial septal defect (ASD) or other cardiac malformations in 12 of 13 patients, and as an isolated anomaly in one patient. Spontaneous closure of ASD by aneurysmal formation of the interatrial septum was observed in 10 patients. The aneurysms of all 13 patients showed a moderate reduction in size, 14 to 25 months (mean 18 months), after these aneurysms has been first diagnosed and 10 subsequently disappeared.It is likely that ASA occurring in infancy will develop in patients with spontaneous closure of an ASD, and that such an aneurysm has a tendency to regress as the patients grows up.     

Atrial septal defect in Malta

OBJECTIVE: To study diagnostic and surgical trends in atrial septal defect (ASD) in a population-based study, and estimate birth prevalence and spontaneous closure rates. METHODOLOGY: All patients in Malta diagnosed as having ASD and born between 1990 and 1994 were identified from various sources. This took place in the setting of a regional hospital supplying diagnostic services for the entire population. Echocardiographic follow-up was also undertaken for lesions not requiring intervention. RESULTS: A total of 190 patients born in this period were diagnosed as having ASD. Age at diagnosis and age at surgery have decreased significantly over the period under study (P < 0.0001). The mode of diagnosis has become entirely noninvasive, and the perioperative mortality decreased dramatically over time. For the period 1990-94, the incidence at birth for defects not requiring intervention was 2.0/1000 live births, defects requiring intervention 0.4/1000 live births. A total of 92% of 50 defects not requiring intervention closed spontaneously, and the remainder had spontaneously decreased in size on follow-up. CONCLUSIONS: ASD is a relatively benign malformation in which early and noninvasive diagnosis can be achieved, with an extremely low interventional mortality.     

Atrial Fibrillation in Two Adolescents

Idiopathic atrial fibrillation (AF) in adolescents is extremely rare and has usually been associated with structural heart disease. We present two cases of symptomatic AF in adolescents without any identifiable etiology. No definitive guidelines are available for management of such patients.     

新生儿心房扑动一例

患儿女 ,第 1胎第 1产 ,孕 37+ 周 ,因母亲产前检查发现胎儿心动过速 (190～ 2 0 0次 /min) ,考虑胎儿宫内窘迫行急诊剖宫产娩出。羊水清 ,Apgar评分 1min 9分 ,5min 10分。出生体重 3kg ,生后吃奶可 ,哭声响 ,无明显烦躁 ,无气促、青紫 ,无呕吐。其母孕前半年曾患成人型麻疹 ,孕期体健 ,无服药史 ,无X射线接触史 ,无家族遗传病史。体检 :反应好 ,口唇红润 ,心音中等 ,心率 180～ 2 0 0次 /min ,律齐 ,无杂音。腹平软 ,肝脾无肿大 ,全身无水肿 ,肌张力适中 ,原始反射存在。实验室检查 :脐带血Hb 178g/L ,K+ 5 4mmol/L ,Na+ 137mmol/L ,…     

Atrial Natriuretic Peptide and Atrial Pressures in Newborns with Transposition of the Great Arteries

ABSTRACT. The relation of atrial pressure to atrial plasma concentration of atrial natriuretic peptide (ANP) was studied in four newborns undergoing catheterization because of transposition of the great arteries. In three patients, mean left atrial pressure clearly exceeded right atrial pressure (12±7 vs. 2±3 mmHg; mean ±SD). In one patient mean atrial pressures were identical (4 mmHg). In all patients the ANP concentration in the left atrium exceeded that of the right (833±464 vs. 415±366 pg/ml; mean ±SD). There was a significant ( r =0.97; p < 0.01) correlation between pressure and ANP concentration in the left atria. In the right atria, no linear correlation existed between pressure and ANP concentration. ANP concentration in the left atrium decreased after a lowering of the left atrial pressure by atrial septostomy. In these patients, the left atrium seems to be the main source of circulating ANP.     

Atrial Ectopic Tachycardia

Respiratory symptoms may be cardiac in etiology and may be precipitated by an arrhythmia-induced cardiomyopathy. Atrial ectopic tachycardia is a rare dysrhythmia in the pediatric population. It can occur in the setting of a structurally normal heart. Persistent tachycardia out of proportion to the level of acuity of illness should alert clinicians to the possibility of AET. A high index of suspicion is required to distinguish AET from other forms of SVT and sinus tachycardia.     

Persistent Atrial Standstill in Noncompaction Cardiomyopathy

Atrial standstill is a rare form of bradyarrhythmia and consists of a transitory or permanent loss of the electrical and mechanical activity of the atria. It has been described in a few cases of long-standing valvular disease, amyloidosis, myocarditis, and muscular dystrophy. We report on a young female with noncompaction cardiomyopathy that progressed to congestive heart failure. Electrocardiogram showed persistence atrial standstill that was confirmed clinically and by electrocardiomyopathy, Doppler two-dimensional echocardiogram, and tissue Doppler imaging. We assume that worsening of asymptomatic noncompaction and progression to the congestive form of cardiomyopathy could be presaged by the presence of persistent atrial standstill. Thus, persistence of atrail standstill in asymptomatic cardiomyopathy is a sign of poor prognosis.     

Right Atrial Isomerism in Four Siblings

Heterotaxy syndromes, right or left atrial isomerism, result from disruption of left–right axis determination and their manifestations include complicated heart defects. Recent studies in model organisms have revealed complex genetic pathways and several genes involved in this process. In affected humans, however, molecular studies have identified mutations in a small number of individuals, while in most the cause remains unknown. Furthermore, although family data suggest, autosomal recessive inheritance, such genes have not yet been identified. We have studied six members of a family, four children affected with right atrial isomerism (RAI) and their healthy parents, for disturbances of left–right axis development. The children, one female and three males who all had complicated heart defects, succumbed and had an autopsy. Their nonconsanguineous parents were examined by cardiac and abdominal ultrasound or MRI. In all four children the heart defects included single ventricle with dysplastic atrioventricular (AV) valve, total anomalous pulmonary venous drainage (TAPVD), and malposition of great arteries (MGA) with pulmonary stenosis (PS). All had asplenia; two also had dextrocardia and abdominal situs inversus. The diagnosis of RAI was made postnatally in the first child and prenatally in others. Two siblings had no surgery and died as a newborn, one with obstructed supracardiac TAPVD and the other with regurgitating AV valve. Two children underwent heart surgery. One had repair of obstructive infracardiac TAPVD but died in infancy. The other underwent both hemi-Fontan operation and heart transplantation but died at the age of 2 years. This is the first report describing four children with RAI in the same family. The occurrence of RAI in male and female siblings without any indication of left–right axis abnormalities in their parents suggests autosomal recessive inheritance of human isomerism.