Spontaneous pericardial hematoma in an infant.

The finding of a pericardial hematoma is rare in the pediatric population. Its occurrence in an otherwise healthy 3-month-old infant is unprecedented in the literature. The hematoma was initially identified by echocardiography. Computerized tomography and magnetic resonance imaging did not contribute to the identification of the mass. An exploratory thoracotomy was necessary to rule out a neoplastic process. The final diagnosis of hemorrhagic pericarditis was made.

Spontaneous resolution of atrioventricular dissociation in utero.

Fetal atrioventricular dissociation is a dysrhythmia associated with significant antenatal and postnatal morbidity and mortality. We present a case of a 19-week-old fetus with atrioventricular dissociation, which spontaneously resolved. The mother had no signs of autoimmune disease. The fetus had an uneventful gestation and, after delivery, had a normal cardiac and transesophageal electrophysiological evaluation.

Intravascular ultrasonic characteristics and vasoreactivity of the pulmonary vasculature in children with pulmonary hypertension.

We sought to describe the morphologic characteristics of pulmonary arteries by intravascular ultrasound (IVUS) in children with and without pulmonary hypertension to compare these anatomic findings with those of pulmonary wedge angiography, and to determine the relation between these structural findings and functional reactivity to pulmonary vasodilators. Direct evaluation of pulmonary vascular structure in children with pulmonary hypertension with current imaging techniques has been limited and little is known about the relation between structural and functional characteristics of the pulmonary vasculature. In 23 children undergoing cardiac catheterization (15 with pulmonary hypertension and 8 controls) we performed IVUS and pulmonary wedge angiography of the distal pulmonary arteries in the same lobe. IVUS was performed in 44 pulmonary arteries measuring 2.5 to 5.0 mm internal diameter with a 3.5Fr 30-MHz IVUS catheter. We assessed vasoreactivity to inhaled nitric oxide (NO) and oxygen in 13 of 15 children with pulmonary hypertension. Baseline pulmonary vascular resistance (PVR) was greater in the 15 children with pulmonary hypertension than in the 8 controls (9.5+/-1.9 vs 1.5+/-0.3 U x m2, p <0.05). NO lowered PVR in patients with pulmonary hypertension (p <0.05). IVUS studies in patients with pulmonary hypertension showed a thicker middle layer, wall thickness ratio, and diminished pulsatility than did those in controls (p <0.05). The inner layer was not visualized by IVUS in any control patient, but was seen in 9 of 15 patients with pulmonary hypertension. Pulmonary artery wedge angiography correlated with baseline mean pulmonary artery pressure and PVR as well as with IVUS findings of wall thickness ratio and inner layer thickness. The inner layer was not visualized by IVUS in any patient with grade 1 wedge angiograms or in 86% of patients with grade 2 wedge angiograms. All patients with grade 4 and 80% of patients with grade 3 wedge angiograms had a visible inner layer. Vasoreactivity to NO and oxygen did not correlate with structural assessment of the pulmonary vasculature by IVUS. Structural changes in the pulmonary arteries in children with pulmonary hypertension can be directly visualized by IVUS, but are not predictive of NO-induced pulmonary vasodilation. IVUS examination of pulmonary arteries may complement current techniques utilized in the evaluation of children with pulmonary hypertension.

Cardiovascular abnormalities in children with autosomal dominant polycystic kidney disease.

It is known that adults with autosomal dominant polycystic kidney disease (ADPKD) have an increased incidence of cardiovascular abnormalities, including mitral valve prolapse. The cardiac manifestations of ADPKD in the pediatric population have not been well established. To determine the cardiac manifestations of children with ADPKD, echocardiography was performed in 154 children of 66 families in which one parent has ADPKD. Eighty-six affected children and 68 unaffected children were evaluated in a prospective, single-blinded manner by echocardiography. Affected children were defined as those with any cysts on a concurrent renal ultrasound or those predicted to be gene carriers by gene linkage analysis. A 12% incidence of mitral valve prolapse was found in the affected children compared with only 3% of the unaffected children (P < 0.05). ADPKD children, but not their unaffected siblings, demonstrate a significant correlation between left ventricular mass index and systolic blood pressure. Moreover, hypertensive ADPKD children have significantly larger left ventricular mass index than do normotensive ADPKD children. A 3.5% incidence of congenital heart disease was found in the affected group, whereas 2.9% of the unaffected children had congenital heart disease. It was concluded that systemic manifestations of ADPKD, particularly cardiovascular abnormalities, are present even in childhood and these warrant the clinician's attention.

Arterial oxygenation and pulmonary arterial pressure in healthy neonates and infants at high altitude.

We sought to document arterial oxygen saturation relative to changes in the right ventricular pressure/left ventricular pressure ratio (RVP/LVP ratio), an index of pulmonary arterial pressure, in infants born at high altitude. We performed pulse oximetry and echocardiography in 15 healthy infants born in Leadville, Colo. (3100 m), at 6 to 24 hours, 24 to 48 hours, 1 week, 2 months, and 4 months of age. Pulse oximetry was done under conditions of wakefulness, feeding, and active and quiet sleep. All infants received supplemental O2 at delivery and during postnatal transition; all oximetry measurements were performed with infants breathing room air. The mean arterial O2 saturation ranged from 80.6% +/- 5.3% to 91.1% +/- 1.7% during the 4 months. Values fell during the first week after birth and then rose gradually to attain near-birth values at 2 and 4 months of age. Arterial O2 saturation was uniform among behavioral states at 6 to 24 hours and 24 to 48 hours of age. After 1 week of age, values were highest during wakefulness, intermediate during feeding and active sleep, and lowest during quiet sleep. The RVP/LVP ratio remained in the normal or mildly elevated range throughout the study period. We conclude that the RVP/LVP ratio promptly becomes normal at high altitude, and despite low arterial O2 saturation in the first weeks to months after birth, healthy newborn infants at 3100 m show little evidence of acute pulmonary hypertension.

Maximal voluntary work and cardiorespiratory fitness in patients who have had Kawasaki syndrome.

To assess the natural history of Kawasaki syndrome and its effect on maximal voluntary work and cardiorespiratory fitness, we performed cycle ergometry testing in 47 patients who had had the syndrome. Forty-one patients performed maximal effort as judged by achievement of 95% predicted heart rate response. Oxygen consumption, carbon dioxide production, and minute ventilation were performed in 23 patients. There was no difference in maximal voluntary work (total work, mean power) or maximal oxygen consumption between case subjects and control subjects. There were no differences between patients with and those without aneurysms. Serial exercise studies were performed in 10 patients; of these, two with initially normal exercise study findings had decreased maximal voluntary work and oxygen consumption with ischemic changes, and both were at high risk for the development of stenotic or occlusive coronary arteries. The other eight patients had normal cardiorespiratory reserve and no ischemic changes with serial studies. These results suggest that patients have normal cardiorespiratory fitness after Kawasaki syndrome. With the development of ischemic heart disease, they may have decreased cardiorespiratory reserve. Serial evaluation of cardiorespiratory fitness may demonstrate ischemic heart disease.

Guidelines for cardiac monitoring of children during and after anthracycline therapy: report of the Cardiology Committee of the Childrens Cancer Study Group.

The anthracycline antibiotics, daunorubicin, doxorubicin, and the newer derivatives, are important components of many antineoplastic chemotherapeutic regimens. Their usefulness is limited by their cardiotoxicity. Sequential monitoring of cardiac function of patients undergoing chemotherapy allows identification of subclinical cardiotoxicity. In many patients monitoring can thus guide the modification of the chemotherapy to minimize cumulative cardiotoxicity, reducing acute and long-term clinical and subclinical sequelae. Such monitoring also aids in the comparison of cardiotoxicity produced by different drugs and different methods and schedules of drug administration. The considerable variability of monitoring regimens between institutions and in the literature has detracted from its usefulness. The Cardiology Committee of the Childrens Cancer Study Group has, therefore, reviewed the field and has formulated recommendations for standardized noninvasive monitoring of children during and immediately after chemotherapy and for the modification of the chemotherapy where indicated.

Congenital polyvalvular disease in trisomy 18: echocardiographic diagnosis.

Congenital heart disease is known to occur in greater than 90% of patients with trisomy 18, with ventricular septal defect and patent ductus arteriosus being the most frequently encountered lesions. The presence of congenital polyvalvular disease in trisomy 18 as assessed by pathological specimens has also been noted. Echocardiograms were obtained in 15 patients with trisomy 18 and in 12 infants with dysmorphic features, who did not have chromosomal abnormalities, in order to obtain an echocardiographic assessment of the frequency of polyvalvular disease in living patients with trisomy 18. In this series all patients with trisomy 18 had structural defects (seven ventricular septal defects, three patent ductus arteriosus, five both). All trisomy 18 patients also had congenital polyvalvular disease with six patients having four affected valves, five patients having three affected valves, and four patients with two affected valves. In patients with normal chromosomes, two had a single abnormal valve, and structural lesions included patent ductus arteriosus (3), ventricular septal defect (2), pulmonary atresia with ventricular septal defect (1), transposition of the great arteries (1), and atrioventricular canal with patent ductus arteriosus and coarctation (1). In infants with features suggestive of trisomy 18, structural cardiac lesions are a nonspecific finding. However, the presence of polyvalvular disease may be a more specific and useful adjunct to other clinical investigations pending chromosomal analysis for definitive diagnosis.

Hereditary atrioventricular conduction defect in a child.

Hereditary atrioventricular conduction defect is an uncommon cause of acquired complete heart block in children. We report a father and son, both of whom presented with seizures as the initial manifestation of acquired complete heart block and required permanent pacemaker implantation. A review of the variations of this entity and the histopathological findings of previously reported cases is presented. Family members of patients with acquired heart block of uncertain etiology should be examined for the presence of conduction abnormalities that may progress to complete heart block.

Pulsed Doppler assessment of left ventricular diastolic filling in children with left ventricular outflow obstruction before and after balloon angioplasty.

To assess left ventricular (LV) diastolic filling in children with pressure overload hypertrophy, 12 patients with LV outflow obstruction (7 with aortic valve stenosis and 5 with aortic coarctation) and 12 healthy, age-matched control subjects were examined. Each child underwent M-mode echocardiography and pulsed Doppler examination of the LV inflow. The patients with LV outflow obstruction had cardiac catheterization and balloon angioplasty. Their echo/Doppler examinations were performed in the catheterization laboratory before and immediately after balloon angioplasty. From the M-mode echocardiogram, the LV cavity dimensions and wall thicknesses, LV mass and shortening fraction were measured. The following measurements were made from the Doppler recording: peak velocities at rapid ventricular filling (peak E) and during atrial contraction (peak A), ratio of peak E to peak A velocities, total area under the Doppler curve, percent of the total Doppler area occurring in the first one-third of diastole (0.33 area fraction), percent of the total area occurring under the E wave (E area fraction), percent of the total area occurring under the A wave (A area fraction) and the ratio of E area to A area.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of verapamil on left ventricular diastolic filling in children with hypertrophic cardiomyopathy.

The effects of oral verapamil on resting left ventricular (LV) diastolic filling were examined in 10 children and adolescents with hypertrophic cardiomyopathy. Measurements of diastolic filling were made from gated technetium-99m radionuclide angiograms with postbeat rejection of data outside a 5% RR-interval window. LV time-activity curves were generated and the rapid-filling phase fit with a 3 degrees polynomial to calculate the peak filling rate and the time from end-systole to the point of peak filling. All patients had a radionuclide angiogram performed before and after 0.25 to 3 years of oral verapamil therapy. Verapamil did not change the LV ejection fraction but increased the peak filling rate (3.24 +/- 0.15 to 4.62 +/- 1.05 end-diastolic volume/s,p less than 0.01) and reduced the time to peak filling (217 +/- 57 to 168 +/- 63 ms, p less than 0.01). An increase in exercise endurance as measured by exercise treadmill test and subjective symptomatic improvement were also seen after verapamil therapy. Thus, in children with hypertrophic cardiomyopathy, symptomatic improvement and LV diastolic filling parameters improved with long-term oral verapamil.

Comparative evaluation of the pulmonary arteries in patients with right ventricular outflow tract obstructive lesions.

The purpose of this prospective study was to assess and compare the roles of CT, sonography, and cineangiography in the evaluation of the central pulmonary arteries. Twenty patients with severe cyanotic congenital heart disease were evaluated. In six patients, cineangiography failed to identify pulmonary arteries (four right, two left) that were seen by CT. Narrowing within the right pulmonary artery was seen more clearly by CT and sonography than by cineangiography in one-third of patients. By contrast, narrowing of the origin of the left pulmonary artery shown by cineangiography was not detected by either CT or sonography in four of four patients. CT has a complementary role and should be performed when the pulmonary arteries are not well seen by cineangiography or sonography, confirmation of the patency and adequacy of the pulmonary arteries is necessary before complete repair, or documentation of interval growth of the pulmonary arteries is desired after palliative surgery.

Sinus of Valsalva aneurysm complicating bacterial endocarditis in an infant: diagnosis with two-dimensional and Doppler echocardiography.

Sinus of Valsalva aneurysm is a rare complication of bacterial endocarditis in infancy and childhood. This report describes an infant with congenital aortic stenosis who developed bacterial endocarditis after abdominal surgery and placement of indwelling central venous catheters for long-term parenteral nutrition. Bacterial endocarditis in this infant was complicated by the development of an aneurysm of the left sinus of Valsalva. Surgical intervention was necessary because of gradual expansion of the aneurysm with compression of the adjacent right pulmonary artery and descending aorta. Two-dimensional and Doppler echocardiography proved useful for the initial diagnosis and serial follow-up of this unusual disorder and for its successful surgical management.

Transseptal left heart catheterization as an aid in the diagnosis of cor triatriatum.

A case of cor triatriatum is described in which transseptal left heart catheterization was useful in making the diagnosis by allowing easy access to the accessory chamber for pressure measurements and angiography.