Temporal flow velocity profile in the descending aorta in coarctation.

The temporal blood flow velocity profile in the descending aorta at the diaphragm was investigated using pulsed Doppler echocardiography in patients with documented coarctation of the aorta and in control patients. The ratio of peak systolic to peak diastolic frequency shift, an angle-independent index of pulsatility derived from the Doppler curve, proved to be an excellent indicator of aortic arch obstruction in the absence of a patent ductus arteriosus. Control groups included patients with a systemic right ventricle, systemic ventricular dysfunction and aortic stenosis, to determine if these conditions would confound the test. None of these factors were found to influence significantly the frequency shift ratio. However, the Doppler curves in six patients with interrupted aortic arch or severe coarctation, whose descending aorta was supplied by way of a large patent ductus arteriosus, were similar to those seen in control patients. Two indexes of wave transmission velocity, the rate of acceleration and the time to peak velocity, discriminated less effectively between patients with coarctation and the control patients, particularly those with aortic stenosis. After surgery for coarctation, the Doppler indexes and contour of the Doppler curve discriminated completely between patients with and without residual coarctation.

Two-dimensional echocardiographic diagnosis of pulmonary artery sling in infancy.

The vascular anomaly in which the left pulmonary artery arises from the right pulmonary artery and passes posteriorly and leftward between the trachea and the esophagus is termed a pulmonary artery sling. Two-dimensional echocardiograms were performed in five infants with this anomaly and successfully identified it in four, including one patient with truncus arteriosus communis. The subxiphoid long-axis sweep was useful in identifying the origin and initial course of the left pulmonary artery, and short-axis subxiphoid views showed both its origin from the right pulmonary artery and its initial posterior course. Angulation toward the cardiac apex displayed the right pulmonary artery in cross section anteriorly and the left pulmonary artery in cross section posteriorly. A transducer orientation midway between the subxiphoid long- and short-axis positions was helpful in distinguishing a large right upper lobe branch of the right pulmonary artery from a pulmonary artery sling. The precordial short-axis plane displayed the origin and initial posterior and leftward course of the left pulmonary artery, while the bifurcation of the main pulmonary artery, usually easily seen in this view, could not be demonstrated. Two-dimensional echocardiography offers a rapid, noninvasive diagnosis of pulmonary artery sling in infants.

Primary surgical closure of ventricular septal defect in the first year of life: results in 128 infants.

Between January 1973 and July 1981, 128 patients less than 1 year of age with failure to thrive, congestive heart failure or pulmonary artery hypertension underwent primary repair of a ventricular septal defect. The hospital mortality rate was 7.8% (10 of 128), and the late mortality rate was 2.3% (3 of 128). Mortality was highest among younger infants with preexisting respiratory problems or a hemodynamically significant residual lesion postoperatively. Complications included a large residual shunt in eight (6.2%), transient neurologic problems in five (3.9%) and persistent complete heart block in three (2.3%). Lung biopsy specimens obtained from 49 patients showed pulmonary vascular abnormalities in all. Complete right bundle branch block developed in 74 (64%) and bifascicular block appeared in 11 (9%). Recatheterization in 70 patients (55%) showed normal pulmonary artery pressures in all but 2 patients with a large residual shunt. Complete closure of the defect had been achieved in 49 (70%), and a hemodynamically insignificant shunt remained in 19 (27%). Patients without significant hemodynamic residua were asymptomatic and tended to accelerate in growth after surgery.

Fate of moderate and large secundum type atrial septal defect associated with isolated coarctation in infants.

A moderate to large secundum atrial septal defect associated with isolated coarctation in infancy is likely to close spontaneously. Nine of 12 defects, including 4 defects > or =8 mm in at least 1 dimension, had either closed or were believed to be hemodynamically insignificant at follow-up, supporting the strategy of a lateral thoracotomy approach to coarctation and deferral of atrial surgery.

Accuracy of prospective two-dimensional echocardiographic evaluation of left ventricular outflow tract in complete transposition of the great arteries.

Thirty-two consecutive infants with transposition of the great arteries (TGA) and ventricular septal defect underwent subxiphoid 2-dimensional echocardiography (2-D echo). Two independent observers prospectively evaluated each echocardiogram for the presence or absence of left ventricular (LV) outflow tract obstruction, whether outflow obstruction was dynamic or fixed, or both, and the precise anatomic type of fixed obstruction. Compared with the LV-to-pulmonary artery gradient determined at cardiac catheterization, 2-D echo yielded low false-negative (7 to 13%) and false-positive (0 to 6%) rates for diagnosing the presence or absence of LV outflow tract obstruction. Moreover, the false-negative cases were only minor errors, because the measured LV-pulmonary artery gradients proved to be less than 25 mm Hg. Compared with the long-axial oblique LV angiogram, 2-D echo yielded no false-negative results in detection of outflow tract obstruction, which was at least partly fixed. Compared with autopsy/surgical observation, 2-D echo made no significant errors in delineating the exact anatomic type of fixed obstruction. The diagnostic accuracy of 2-D echo in detecting and characterizing LV outflow tract obstruction limits the need for "routine" cardiac catheterization before repair in infants with TGA and intact ventricular septum. Furthermore, because certain types of fixed LV outflow tract obstruction are difficult for the surgeon to visualize and alleviate, precise knowledge of the anatomic type of fixed obstruction influences the choice among Rastelli, intraatrial baffle and arterial switch procedures in patients with TGA and ventricular septal defect.

Pulmonary valve stenosis associated with hypertrophic cardiomyopathy.

The association of pulmonic stenosis with hypertrophic cardiomyopathy is rare in infancy. Presented here is an infant with atypical picture of pulmonic stenosis and echocardiographic evidence of hypertrophic cardiomyopathy. At eight months of age, she had a successful percutaneous balloon valvuloplasty and has subsequently been managed with propranolol.

Sudden death in infants with chaotic atrial rhythm.

In four cases of chaotic atrial rhythm in infancy, three infants died, two unexpectedly. Chaotic atrial rhythm may be associated with a relatively high mortality in the first year of life.

Prediction of arterial blood pressure in the premature neonate using the oscillometric method.

The noninvasive oscillometric measurement of blood pressure (BP) in preterm neonates has become a common practice in intensive care nurseries. The method has gained acceptance primarily through its correlation with direct arterial measurement. In this study, the oscillometric method (using Dinamap 1846) was compared with direct intra-arterial BP monitoring in 15 preterm infants. The 95% prediction intervals for individual oscillometric measurements were wide, ranging from 17 mm Hg for the mean BP to 20 mm Hg for the systolic and diastolic BP. The oscillometric method also underestimated intra-arterial systolic and mean BP and overestimated diastolic BP. Caution must be used when oscillometrically measuring BP in premature neonates.

Echocardiographic diagnosis of fetal heart defects in mid trimester.

One hundred and thirty five consecutive fetuses of between 16 and 23 weeks' gestation that were considered to be at high risk of having structural heart defects were examined prospectively to determine the reliability of echocardiography for diagnosing such defects in mid trimester. Each echocardiogram was done in a standard manner and cardiac anatomy was analysed segmentally. Twelve fetuses were excluded from analysis because of lack of follow up. Of the remaining 123 fetuses, 109 had no evidence of heart disease when followed up. In this group the prenatal echocardiogram was normal in 105 and technically inadequate in four; thus there were no false positive diagnoses of heart disease in fetuses subsequently shown to have normal hearts. Fourteen had heart defects at follow up. The serious defect was correctly diagnosed prenatally in 10 of 14 cases, whereas in the other four the prenatal echocardiogram was considered normal. Some errors were made in diagnosing associated segmental defects particularly if the heart disease was complicated. Therapeutic abortion was carried out in seven cases; in five of the fetuses the prenatally diagnosed heart defect was the sole or an important contributing reason for the abortion. We conclude that echocardiography is a reliable method for diagnosing many heart defects in the mid trimester.

Extraskeletal Ewing's sarcoma of primary cardiac origin.

A 13-year-old boy presented with cardiac tamponade. Echocardiography revealed a large mass extending from the right and left ventricles into a large pericardial effusion. Pathology confirmed the first reported case of a primary cardiac extraskeletal Ewing's sarcoma.