Are ECG abnormalities in Noonan syndrome characteristic for the syndrome?

Of all patients with Noonan syndrome, 50-90% have one or more congenital heart defects. The most frequent occurring are pulmonary stenosis (PS) and hypertrophic cardiomyopathy. The electrocardiogram (ECG) of a patient with Noonan syndrome often shows a characteristic pattern, with a left axis deviation, abnormal R/S ratio over the left precordium, and an abnormal Q wave. The objective of this study was to determine if these ECG characteristics are an independent feature of the Noonan syndrome or if they are related to the congenital heart defect. A cohort study was performed with 118 patients from two university hospitals in the United States and in The Netherlands. All patients were diagnosed with definite Noonan syndrome and had had an ECG and echocardiography. Sixty-nine patients (58%) had characteristic abnormalities of the ECG. In the patient group without a cardiac defect (n = 21), ten patients had a characteristic ECG abnormality. There was no statistical relationship between the presence of a characteristic ECG abnormality and the presence of a cardiac defect (p = 0.33). Patients with hypertrophic cardiomyopathy had more ECG abnormalities in total (p = 0.05), without correlation with a specific ECG abnormality. We conclude that the ECG features in patients with Noonan syndrome are characteristic for the syndrome and are not related to a specific cardiac defect. An ECG is very useful in the diagnosis of Noonan syndrome; every child with a Noonan phenotype should have an ECG and echocardiogram for evaluation.

Long-term outcome in congenitally corrected transposition of the great arteries: a multi-institutional study.

OBJECTIVES: The purpose of this study was to determine long-term outcome in adults with congenitally corrected transposition of the great arteries (CCTGA), with particular emphasis on systemic ventricular dysfunction and congestive heart failure (CHF). BACKGROUND: Patients with CCTGA have the anatomical right ventricle as their systemic pumping chamber, with ventricular dysfunction and CHF being relatively common in older adults. METHODS: Retrospective analysis of records of 182 patients from 19 institutions were reviewed to determine current status and possible risk factors for systemic ventricular dysfunction and CHF. Factors considered included age, gender, associated cardiac defects, operative history, heart block, arrhythmias and tricuspid (i.e., systemic atrioventricular) regurgitation (TR). RESULTS: Both CHF and systemic ventricular dysfunction were common in groups with or without associated cardiac lesions. By age 45, 67% of patients with associated lesions had CHF, and 25% of patients without associated lesions had this complication. The rates of systemic ventricular dysfunction and CHF were higher with increasing age, the presence of significant associated cardiac lesions, history of arrhythmia, pacemaker implantation, prior surgery of any type, and particularly with tricuspid valvuloplasty or replacement. Aortic regurgitation (a previously unreported problem) was also relatively common in this patient population. CONCLUSIONS: Patients with CCTGA are increasingly subject to CHF with advancing age; this complication is extremely common by the fourth and fifth decades. Tricuspid (systemic atrioventricular) valvular regurgitation is strongly associated with RV (anatomical right ventricle connected to aorta in CCTGA patients; systemic ventricle in CCTGA) dysfunction and CHF; whether it is causative or a secondary complication remains speculative.

Late echocardiographic findings following childhood chemotherapy with normal serial cardiac monitoring.

PURPOSE: Late development of myocardial dysfunction years following successful treatment of childhood malignancy with anthracyclines is well documented. There have been few studies of late cardiac performance in children in whom serial monitoring during treatment suggested normal cardiac performance, and those studies that do exist rely on the results of extensive evaluation. It was our purpose to determine whether findings consistent with known late cardiac changes could be discovered in these patients by echocardiographic monitoring similar to that routinely performed during treatment. PATIENTS AND METHODS: A total 28 consecutive asymptomatic patients who had completed anthracycline therapy at least 3 years previously, had been free of malignant disease since the completion of therapy, and who had had normal serial echocardiographic studies during and at completion of treatment were restudied by echocardiography. Of these 28, 12 had undergone mediastinal radiation as part of their acute treatment. RESULTS: Four patients (14%) of the study group were found to have abnormally low values for left ventricular shortening and ejection fractions. All four had also received mediastinal radiation. The remaining 24 patients, while having values for shortening fraction within the normal range, had, as a group, experienced a significant decrease in echocardiographic left ventricular shortening since completion of treatment. In these patients, left ventricular wall thickness had not increased commensurate with growth in body size and left ventricular cavity dimension. CONCLUSIONS: The known incidence of late asymptomatic cardiac dysfunction is confirmed despite the presence of persistently normal echocardiographic monitoring studies during and at completion of anthracycline treatment. Additionally, as a population, these patients show impaired myocardial growth over time, placing them at risk for future myocardial failure. Normal echocardiographic monitoring studies during antineoplastic treatment in children may not necessarily predict that patients will be free of the development of late cardiac dysfunction. Routine serial echocardiographic monitoring can, however, be helpful in the long-term management of these patients.

Changes in left ventricular diastolic filling patterns by Doppler echocardiography in cystic fibrosis.

The onset of cor pulmonale is a common terminal finding in patients with cystic fibrosis. Since Doppler echocardiography can detect changes in diastolic filling patterns prior to the onset of either systolic dysfunction or clinical symptoms, we utilized this technique to determine whether detectable changes in left ventricular diastolic filling patterns exist in patients with cystic fibrosis. Among 25 patients, the proportion of left ventricular filling attributable to atrial contraction was significantly increased when compared with age-matched control individuals. When filling patterns were compared with severity of pulmonary disease, worsening pulmonary disease was directly correlated to shifts in left ventricular filling patterns. We conclude that changes in left ventricular patterns of relaxation are detectable early in the course of cystic fibrosis and that such changes are probably progressive. Early detection could lead to therapeutic trials designed to improve left ventricular filling and delay the onset of overt cor pulmonale.

Doppler echocardiographic studies of diastolic ventricular filling patterns in premature infants.

Pulsed Doppler echocardiographic studies of both right and left ventricular diastolic inflow patterns were performed in 10 full-term newborn infants and serially during the first month of life in 21 premature (28 to 35 weeks' gestation) infants with no clinical cardiorespiratory disease. Results of studies performed during the first 10 days of life showed no significant difference in transmitral flow velocity or velocity-time integral measurements between full-term and preterm neonates. Values for transtricuspid velocity measurements were slightly lower in preterm infants, but E/A velocity ratio and relative contribution of E and A components to the total velocity-time integral were unchanged. Within the group of preterm infants gestational age did not affect any of the diastolic flow parameters. As preterm infants aged velocity of flow increased, but no changes were noted in the relative contributions of rapid ventricular filling and atrial contraction, either in terms of velocity of flow-velocity integral measurements. Doppler assessment of diastolic ventricular filling can provide an accessible method for serial evaluation of preterm infants. Values noted in "normal" premature infants resemble those found in full-term infants.

Ventriculocoronary connections in hypoplastic right heart syndrome: autopsy serial section study of six cases.

Myocardial sinusoids communicating with the coronary systems occur in pulmonary atresia with intact ventricular septum. To test the hypothesis that the extent of ventriculocoronary connections correlates with the degree of right ventricular outflow obstruction as evidenced by clinical, angiographic and gross anatomic findings, a serial section study of six human autopsy hearts representing a spectrum of hypoplastic right heart was undertaken. Slides were evaluated for the presence and extent of ventriculocoronary connections, associated developmental abnormalities and secondary changes in the ventricular walls. Whereas extensive blind-ended deep sinusoids were a feature of all five cases with unrelieved obstruction, ventriculocoronary connections were identified in three. Changes that suggested ongoing remodeling provide new evidence for the postnatal temporal evolution of these anomalous communications. The regional distribution of myofiber disarray in hypoplastic right heart supports the concept that vascularization parallels myocardial organization in the developing human heart.

Effect of sample volume location on pulsed Doppler diastolic flow parameters in newborn infants.

Pulsed Doppler echocardiography was used to measure parameters of left and right ventricular diastolic filling from both the valve annulus and valve leaflet tips in 36 newborn infants. Absolute values for E and A velocities were 13% higher at the mitral leaflet tips and 10%-18% higher at the tricuspid tips than at the respective valve annulus. Similarly, values for diastolic velocity-time integral measurements were 6%-18% higher when sampling was performed at the leaflet tips. With the exception of the transtricuspid velocity ratio, E/A ratio values were not affected by sample volume location. Doppler sample volume location can influence velocity and velocity-time integral measurements in newborn infants. Attention to consistent sample volume location is important in serial or comparative studies.

Down's syndrome.

We discuss the ethical, psychosocial, economic, and medical dimensions of the treatment and management of a child with Down's syndrome and a congenital heart defect.

Parental genetic contribution to mode of presentation in Pompe disease.

Echocardiograms were performed on parents of five infants with Pompe disease (glycogen storage disease, type II). Three of the infants had presented with congestive cardiomyopathy and two with dynamic muscular subaortic stenosis. No heart murmurs were audible in any of the parents of the five infants. The parents of the three infants without left ventricular outflow tract obstruction had normal echocardiographic results, whereas one parent of each of the infants with left ventricular outflow obstruction had asymmetric septal hypertrophy. The association between left ventricular outflow obstruction and parental asymmetric septal hypertrophy suggests that both septal hypertrophy and glycogen storage disease were inherited by these two infants.

Mitral valve prolapse in patients with anorexia nervosa and bulimia.

We studied 43 consecutive individuals with eating disorders (anorexia nervosa and/or bulimia) for the presence of mitral valve prolapse and/or cardiac arrhythmias by physical examination, M-mode and two-dimensional echocardiography, and 24-hour continuous ambulatory electrocardiographic monitoring. Ten of the 43 had findings of mitral valve prolapse on resting cardiac auscultation. Echocardiographic evaluation confirmed the diagnosis of mitral valve prolapse in these ten as well as in six other individuals, giving an overall incidence of 37% (16/43). Similar echocardiographic findings were present in only 4% (1/23) of control individuals. Cardiac arrhythmias other than benign isolated premature extrasystoles were noted in five patients with eating disorder; all five also had echocardiographic findings of mitral valve prolapse. The incidence of mitral valve prolapse appears to be increased in patients with eating disorders. In addition, the arrhythmogenic effects of mitral valve prolapse may present an additional risk factor in these patients.

Ventricular septal defect with mobile tricuspid valve pouch mimicking tetralogy of Fallot.

A newborn with partial deletion of the long arm of chromosome six presented with cyanosis at birth. Initial studies suggested the diagnosis of tetralogy of Fallot and the infant underwent a Waterston shunt procedure with subsequent clinical improvement. The infant subsequently died of unrelated causes. Autopsy revealed a ventricular septal defect and a dysplastic pouchlike structure related to an anomalous tricuspid valve leaflet which obstructed right ventricular outflow. Classical anatomic findings of tetralogy of Fallot were absent. Clinical and echocardiographic findings that would be expected to aid early diagnosis of future cases are presented.

Anomalous left coronary artery from the pulmonary artery: significance of associated intracardiac defects.

Two patients with anomalous origin of the left main coronary artery from the pulmonary artery had an associated defect (one, critical pulmonary stenosis; the other, ventricular septal defect). They presented with signs and symptoms of the associated defect and the coronary anomaly was unrecognized. Both cases at autopsy lacked the usual large right coronary artery seen with this anomaly. The pathophysiologic features of the combined defects are described, their differences from the isolated anomaly are noted and their relation to surgery is discussed.