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Background: To assess the reliability of pediatric echocardiographic measurements, we compared local measurements with those made at a central facility., Methods and Results: The comparison was based on the first echocardiographic recording obtained on 735 children of HIV-infected mothers at 10 clinical sites focusing on measurements of left ventricular (LV) dimension, wall thicknesses, and fractional shortening. The recordings were measured locally and then remeasured at a central facility. The highest agreement expressed as an intraclass correlation coefficient (ICC=0.97) was noted for LV dimension, with much lower agreement for posterior wall thickness (ICC=0.65), fractional shortening (ICC=0.64), and septal wall thickness (ICC=0.50). The mean dimension was 0.03 cm smaller in central measurements (95% prediction interval [PI], -0.32 to 0.25 cm) for which 95% PI reflects the magnitude of differences between local and central measurements. Mean posterior wall thickness was 0.02 cm larger in central measurements (95% PI, -0.18 to 0.22 cm). Mean fractional shortening was 1% smaller in central measurements. However, the 95% PI was -10% to 8%, indicating that a fractional shortening of 32% measured centrally could be anywhere between 22% and 40% when measured locally. Central measurements of mean septal thickness were approximately 0.1 cm thicker than local ones (95% PI, -0.18 to 0.34 cm). Centrally measured wall thickness was more closely related to mortality and possibly was more valid than local measurements., Conclusions: Although LV dimension was reliably measured, local measurements of LV wall thickness and fractional shortening differed from central measurements.

Background: Accurate quantitative evaluation of right ventricular (RV) function has been limited by its complex structural geometry. Although embryological and anatomic observations suggest that the RV is composed of 2 distinct components, the RV sinus and infundibulum, most studies on RV dimensions and function viewed it as a single chamber. This study was designed to determine the volumes, relative contribution to global systolic function, and temporal course of contraction and relaxation of the RV sinus and infundibulum., Methods and Results: Thirty-one individuals without heart disease (aged 1 month to 17 years, 16 boys and 15 girls) participated in this study. Instantaneous area over time, its derivatives, and the temporal course of contraction and relaxation were studied by acoustic quantification echocardiography and phonocardiography in 20 individuals. Global and regional RV volumes and ejection fraction were determined by cine MRI in 11 individuals. The RV sinus made up 81+/-6% of the combined RV end-diastolic volume and 87+/-4% of the combined stroke volume. The infundibulum accounted for the remaining 19+/-6% and 13+/-4%, respectively (P<0.0001). Compared with the infundibulum, the extent of RV sinus fiber shortening was significantly greater: for ejection fraction (56+/-11% versus 38+/-13%, P<0.001), fractional area change (42+/-14% versus 28+/-9%, P<0.0001), and dA/dt (27+/-17% versus 13+/-6%, P<0.0001). Analysis of temporal course of contraction and relaxation (expressed as percentage of the cardiac cycle to adjust for differences in heart rate) showed that the infundibulum follows the RV sinus: onset of contraction 53%+/-14 versus 19+/-11% of systole, time to peak systole 115+/-16% versus 97+/-19% (P< or =0.01), indicating a peristalsis-like pattern of contraction and relaxation., Conclusions: The results of this study demonstrate significant regional differences between the sinus and infundibulum components of the RV with regard to contribution to stroke volume, extent of fiber shortening, and sequence of mechanical activation. These data from normal individuals can be used in future research on RV function in pathological conditions.

Background: The frequency of, course of, and factors associated with cardiovascular abnormalities in pediatric HIV are incompletely understood., Methods and Results: A baseline echocardiogram (median age, 2.1 years) and 2 years of follow-up every 4 months were obtained as part of a prospective study on 196 vertically HIV-infected children. Age- or body surface area-adjusted z scores were calculated by use of data from normal control subjects. Although 88% had symptomatic HIV infection, only 2 had CHF at enrollment, with a 2-year cumulative incidence of 4.7% (95% CI, 1.5% to 7.9%). All mean cardiac measurements were abnormal at baseline (decreased left ventricular fractional shortening [LV FS] and contractility and increased heart rate and LV dimension, mass, and wall stresses). Most of the abnormal baseline cardiac measurements correlated with depressed CD4 cell count z scores and the presence of HIV encephalopathy. Heart rate and LV mass showed significantly progressive abnormalities, whereas FS and contractility tended to decline. No association was seen between longitudinal changes in FS and CD4 cell count z score. Children who developed encephalopathy during follow-up had depressed initial FS, and FS continued to decline during follow-up., Conclusions: Subclinical cardiac abnormalities in HIV-infected children are common, persistent, and often progressive. Dilated cardiomyopathy (depressed contractility and dilatation) and inappropriate LV hypertrophy (elevated LV mass in the setting of decreased height and weight) were noted. Depressed LV function correlated with immune dysfunction at baseline but not longitudinally, suggesting that the CD4 cell count may not be a useful surrogate marker of HIV-associated LV dysfunction. However, the development of encephalopathy may signal a decline in FS.

Background: Radiographic evidence of cardiomegaly is common in patients with congenital complete atrioventricular block (CCAVB). It has been speculated that left ventricular (LV) remodeling and increased stroke volume counteract the bradycardia, but the effects of slow heart rate and atrioventricular asynchrony on LV dimensions, geometry, wall stress, and function have not been examined in detail., Methods and Results: Thirty patients with CCAVB without associated congenital heart disease (mean age, 8.5+/-5.3 years; range, 0.2 to 20 years) were included in a cross-sectional two-institution study. Thirty-five echocardiograms were performed using standard techniques. ECG and 24-hour ECG recordings were reviewed. Seven patients did not receive a pacemaker, whereas 23 patients underwent pacemaker implantation after the echocardiogram. Compared with normal control subjects, LV volume (Z score=1.5+/-1.3) and LV mass (Z=1.2+/-1.5) were significantly increased, whereas LV mass-to-volume ratio (1.1+/-0.3) and geometry (short-axis diameter/length ratio=0.65+/-0.09) were normal. LV end-systolic stress (ESS) (a measure of afterload) was normal (Z score=0.2+/-2.3), whereas shortening fraction (Z=3+/-2.9) and velocity of circumferential fiber shortening (VCF) (Z=3+/-3.1) were increased. The relationship between VCF and ESS (a preload-insensitive and afterload-adjusted index of contractility) was increased (Z=2.2+/-2) with only small increase in preload (Z=1.02+/-1.1). Regression analyses showed no significant change over age in LV mass, volume, geometry, loading conditions, or systolic function. Patients who ultimately met criteria for pacemaker implantation did not differ from those who did not in terms of heart rate or LV function but did have increased LV volume (Z score=1.8+/-1.4 versus 0.4+/-0.9, P=.03) and LV mass (Z score=1.7+/-1.2 versus 0.2+/-1.7, P=.001) compared to the unpaced group., Conclusions: In most patients with CCAVB, the LV was enlarged with normal geometry and enhanced systolic function during the first two decades of life. The degree of LV dilation and enhanced function did not significantly change with age. In patients who ultimately underwent pacemaker implantation LV function did not differ from those who remained unpaced, but evidence of a slightly increased load manifested as increased end-diastolic volume and mass.

Background: Previous reports suggest a poor prognosis for patients with ectopia cordis and significant congenital heart disease., Methods and Results: To determine the outcome of affected patients in a recent medical and surgical era, we reviewed the clinical course, echocardiograms, catheterization data, and operative reports of all patients with ectopia cordis and significant heart disease encountered at Children's Hospital from 1982 to the present. We identified 13 patients with conotruncal defects and either thoracic (TEC, n = 4) or thoracoabdominal (TAEC, n = 9) ectopia cordis. Diagnosis was established in utero in 6, with termination of pregnancy in 2 and death before transfer to Children's Hospital in 1. Of 10 patients postnatally managed at Children's Hospital, 4 of 8 with TAEC and 1 of 2 with TEC survived beyond infancy, with an age at most recent follow-up of 3.5 to 9.8 years. All 5 survivors had procedures as neonates to provide skin coverage over the midline defect and heart, with concomitant repair of a small omphalocele in 4. Three underwent successful surgical repair of the cardiac defect, including ventricular septal defect closure for double-outlet right ventricle (9 months), repair of tetralogy of Fallot with pulmonary atresia (2.6 years), and repair of double-outlet right ventricle, pulmonary stenosis, and total anomalous pulmonary venous connection to the coronary sinus (3.3 years). Two other patients with TAEC, conoventricular defects, and hypoplastic left ventricle underwent single-ventricle palliation. One patient, at 4 years of age underwent a right cavopulmonary anastomosis and intra-atrial coronary sinus-to-right superior vena cava baffle. The second patient had a modified Fontan procedure. None of the 5 survivors had significant extrathoracic defects, whereas all 3 who died by 3 weeks of age had both a large omphalocele and pulmonary hypoplasia. Two infants with pentalogy of Cantrell, 1 with a large omphalocele, died of fungal sepsis by 5 weeks of age, and 1 other died intraoperatively after repair of pulmonary venous confluence obstruction and right Blalock-Taussig shunt placement., Conclusions: Our experience indicates that patients with TEC and TAEC and significant intracardiac defects, in the absence of significant extracardiac defects, can survive beyond early infancy and undergo successful cardiac repair or more definitive palliation for single-ventricle physiology.

Background: Pregnancy represents an excellent model of acute physiological hypertrophy and atrophy secondary to a transient hemodynamic load. This investigation examined the effects of pregnancy on ventricular mechanics using load-independent indexes of contractility to test the hypothesis that the cardiac trophic response functions as a servomechanism with wall stress as the feedback variable., Methods and Results: Serial studies were performed in 33 women at six time periods during and shortly after normal gestation. Changes in ventricular dimension, wall thickness, and left ventricular mass were parallel to changes in body size. Fractional shortening and velocity of shortening progressively diminished during pregnancy, with a nadir at the first postpartum examination, despite a progressive fall in afterload. Cardiac index rose rapidly in early gestation and remained elevated throughout pregnancy. Peak wall stress was elevated in early gestation coincident with the rapid rise in cardiac index due to elevated volume before compensatory rise in mass. With compensatory hypertrophy, peak wall stress normalized by midgestation. The change in left ventricular mass was closely related to peak wall stress but correlated poorly with mean, total, and end-systolic wall stress., Conclusions: Normal pregnancy is associated with a reversible fall in contractility. Systolic function is preserved throughout most of pregnancy by a fall in afterload but decreases near term and early postpartum because of decreased contractility and diminished preload. Left ventricular hypertrophy and atrophy are temporally related to changes in hemodynamic load. The response is consistent with a tightly coupled servomechanism transduced by peak wall stress with a 1- to 4-week compensatory response time.

Background: Progressive left ventricular (LV) dilation is common in children infected with HIV-1 and may be a harbinger of congestive heart failure (CHF). In many HIV-infected children, dilation is associated with inadequate LV hypertrophy, elevated afterload, and reduced LV function. Because CHF has been observed empirically to improve after treatment with intravenous immunoglobulin (IVIG) in other conditions and because LV dysfunction in pediatric HIV may be immunologically mediated, we examined retrospectively the relation between immunoglobulins and LV structure and function in 49 HIV-infected infants and children without CHF., Methods and Results: A total of 106 echocardiograms were performed in these children within 30 days of serum immunoglobulin (IgG, IgA, and IgM) measurements; this includes 12 children treated with IVIG therapy. All echocardiographic parameters, blood pressures, and immunoglobulins were adjusted for age or body surface area and subjected to repeated-measures regression. Regression models were adjusted simultaneously for endogenous IgA, IgG, IgM, IVIG therapy, zidovudine therapy, age, HIV disease stage, and weight. Higher endogenous serum IgG levels and IVIG treatment were associated with significantly greater wall thickness and lower peak wall stress. Higher endogenous serum IgA levels were associated with more normal LV wall thickness and LV thickness-to-dimension ratios. LV contractility, fractional shortening, end-systolic wall stress, and thickness-to-dimension ratio all showed a trend toward more normal values with higher endogenous immunoglobulin values or during IVIG treatment., Conclusions: LV structure and function appear to be more normal in HIV-infected children who receive IVIG treatment and in those with higher endogenous IgG levels. These results suggest that both the impaired myocardial growth and the LV dysfunction observed may be immunologically mediated and responsive to immunomodulatory therapy.

Background: Isolated case reports that suggest the potential for development of left heart hypoplasia late in gestation provide the only information about the in utero natural history of left heart obstructive lesions., Methods and Results: We reviewed the prenatal and postnatal echocardiograms of 21 fetuses with left heart obstructive lesions, including 15 with serial antenatal study, to elucidate the antenatal natural history of this spectrum of disease and to identify features indicative of postnatal disease severity. Ventricular, atrioventricular valve, and great artery dimensions were measured and growth curves were developed with comparisons to data from 47 normal fetuses. Fetuses were divided into groups according to whether postnatally the left heart was capable (group 1, n = 10) or incapable (group 2, n = 7) of supporting the systemic circulation in the presence of a patent aortic valve. Group 3 (n = 4) included fetuses with aortic atresia. At the initial examination (21.7 +/- 3.4 weeks' gestation), left heart dimensions were normal or reduced, with the most diminutive measurements in group 3. Three fetuses in group 2 and most in group 1 had normal initial left heart dimensions. Subsequent growth of left heart structures either paralleled normal growth or was reduced, the latter resulting in the development or progression of left heart hypoplasia. All left heart dimensions grew more slowly in group 2 and group 3 than in group 1 (P < .05). Other prenatal features observed only in groups 2 and 3 included reversed (n = 10) or bidirectional (n = 1) foramen ovale flow and retrograde distal arch flow (n = 9). Initial midtrimester mitral valve and ascending aorta z scores and the growth rates of all left heart structures correlated strongly with postnatal left ventricular end-diastolic dimension (P = .0007 to .03, r = .57 to .82) and could be additional indicators of postnatal disease severity. One group 1 fetus developed severe aortic stenosis late in gestation., Conclusions: The potential for the in utero development or progression in severity of left heart obstruction and hypoplasia in left heart obstructive lesions necessitates serial prenatal study in affected fetuses carried to term.

Background: Right ventricular decompression (RVD) may cause myocardial ischemia in patients with pulmonary atresia with intact ventricular septum and associated coronary artery abnormalities. Although we have previously shown that mortality is very high when two or more coronary arteries are obstructed, the effects of lesser degrees of coronary abnormalities are unknown. We therefore evaluated the effect of RVD on left ventricular (LV) function in those with less extensive coronary artery abnormalities., Methods and Results: Preoperative cineangiograms demonstrated fistulas with or without one coronary artery stenosis in 12 of 24 patients aged 2 days to 33 months at the time of RVD. Preoperative and postoperative two-dimensional echocardiograms were analyzed for global and regional LV function. One infant with fistulas involving two coronary arteries and stenosis of the right coronary artery died from severe global LV dysfunction after RVD. Despite this, mean LV end-diastolic volume (66 +/- 17 mL/m2) and mean LV ejection fraction (60 +/- 9%) were similar in patients with and without coronary artery abnormalities before and after RVD. Before RVD, regional LV dysfunction was seen in 8 of 132 (6%) regions in those with coronary artery abnormalities and in 3 of 132 (2%) in those without coronary artery abnormalities. After RVD, there were 16 of 132 (12%) abnormal regions in those with coronary artery abnormalities and 1 of 132 (< 1%) in those without coronary artery abnormalities. In regions with normal wall motion before RVD, the presence of coronary artery abnormalities was related to regional LV dysfunction after RVD (P < .001)., Conclusions: Regional LV dysfunction was rare in patients without coronary artery abnormalities. In those with less extensive coronary artery abnormalities not involving obstruction to multiple coronary arteries, regional LV dysfunction was common before and increased after RVD, but severe global LV dysfunction was unusual.

Background: Two-dimensional and Doppler echocardiography can provide structural and hemodynamic information for patients with ventricular septal defects (VSDs). Therefore, two-dimensional and Doppler echocardiographic examinations were performed on patients with VSDs returning for the Second Natural History Study of Congenital Heart Defects., Methods and Results: Five hundred fifty-six patients with VSDs underwent two-dimensional and Doppler echocardiographic examinations. Three hundred twenty-four patients were in the medically treated group, and 232 had undergone a previous operation. The location of the VSD was classified in 235 patients. Several Doppler measurements were used to calculate pulmonary artery pressures: tricuspid regurgitation peak systolic velocity, peak systolic velocity of VSD jet, pulmonary regurgitation end-diastolic velocity, and pulmonary artery acceleration time. The two methods that were found to be reliable consisted of the tricuspid regurgitation peak systolic velocity and the pulmonary regurgitation end-diastolic velocity. These measurements were obtained in only 26% of patients at all centers. At one center in which adult and pediatric echocardiography was performed in a single laboratory, these values were obtained in 60% of patients., Conclusions: Two-dimensional and Doppler echocardiography has the ability to provide a noninvasive method of assessing morphology and hemodynamics in patients with VSDs. However, the reliability and accuracy of hemodynamic measurements are dependent on operator experience.

Background: Recent advances in the field of echocardiography have made it possible to obtain a complete morphological and hemodynamic assessment of patients with aortic stenosis. Therefore, comprehensive two-dimensional and Doppler examinations were performed on patients with aortic stenosis returning for the Second Natural History Study of Congenital Heart Defects (NHS-2)., Methods and Results: Two hundred thirty-two patients with aortic stenosis underwent comprehensive two-dimensional and Doppler examinations. Of these, 96 were in the medically treated group, 49 had undergone aortic valve replacement, and 87 had had aortic valvotomy. The valve replacement group had a significantly smaller left ventricular diastolic cavity than did the medically treated group; both had smaller dimensions than the valvotomy group. There was no significant difference in left ventricular wall thickness or fractional shortening among the three groups. The valvotomy group had a significantly higher mean aortic valve gradient than did either the medically treated group or the valve replacement group. The degree of aortic regurgitation was more severe in the valvotomy group than in the other two groups. For all patients, there was a direct relation between the aortic valve gradient and the mean wall thickness and an inverse relation between the aortic valve mean gradient and fractional shortening. The only echocardiographic parameter that correlated with the presence or absence of symptomatology was the fractional shortening., Conclusions: These observations provide an objective measurement for assessing the status of the aortic valve and left ventricular response in patients with aortic stenosis returning for NHS-2. Limitations of echocardiography in this study are discussed.

Background: Two-dimensional and Doppler echocardiography can provide information about valve morphology, right ventricular size and function, and hemodynamics in patients with pulmonary stenosis. Therefore, two-dimensional and Doppler echocardiographic examinations were performed on patients with pulmonary stenosis returning for the Second Natural History Study of Congenital Heart Defects., Methods and Results: Three hundred twenty-five patients with pulmonary stenosis underwent two-dimensional and Doppler echocardiographic examinations. Of these, 115 were in the medically treated group, and 210 had undergone a previous operation. Patients in the valvotomy group had a higher incidence of right ventricular dysfunction and a larger right ventricular diastolic dimension. The valvotomy group had a lower pulmonary valve mean gradient and a lower right ventricular systolic pressure than the medically treated group. For all patients, there was no significant correlation of the echocardiographic variables with the presence or absence of symptoms, reflecting the low incidence of patients with cardiac decompensation., Conclusions: These observations provide an objective measurement for assessing the status of the pulmonary valve and right ventricular response in patients with pulmonary stenosis. Limitations of echocardiography in this study are discussed.

Background: In patients with transposition of the great arteries with low left ventricular pressure, pulmonary artery banding with aortopulmonary shunt placement has been advocated to "prepare" the left ventricle for systemic work before an arterial switch operation., Methods and Results: In 28 patients, this preparatory procedure was performed with one death. A successful arterial switch operation was performed at a median of 7 days later in 24 of 27 survivors; one child had a Senning performed, and two others died. During this interval period, the left ventricular-to-right ventricular pressure ratio increased from 48 +/- 8% to 98 +/- 19%, and left ventricular mass (indexed for body surface area) increased from 46 +/- 17 to 72 +/- 23 g/m2. After the preparatory procedure, the initial postoperative period was frequently characterized by a low-output syndrome of variable length and severity. Prolonged mechanical ventilation, extended inotropic support, and/or a significant metabolic acidosis was present in 21 of 28 patients in the immediate postoperative period., Conclusions: The low-output syndrome is most likely due to a combination of acute (fixed) right ventricular volume overload from the shunt and acute (transient) left ventricular dysfunction from the pulmonary artery band. This low-output syndrome should be anticipated following the preparatory procedure.

The anatomic pulmonary valve, which has thin leaflets with little elastic tissue in the normal heart, must function as the neoaortic valve after arterial switch operation (ASO) for transposition of the great arteries, palliative surgery for hypoplastic left heart syndrome (HLHS), and pulmonary artery-to-aortic (P-A) anastomosis for complex heart disease with subaortic obstruction. The long-term function of this valve under these circumstances is not known. To investigate the function of this valve in the systemic circulation, the follow-up echocardiograms, catheterization data, and angiograms were reviewed for 189 patients at our institution after an ASO (n = 112), palliative surgery for HLHS (n = 45), or P-A anastomosis (n = 32). In addition, the effect on valve function of preoperative anatomy, prior placement of a pulmonary artery band (PAB), and length of follow-up was examined. Neoaortic regurgitation was present in 41% of patients after an ASO (mean +/- SD) follow-up (20 +/- 20; range, 2.2-80.5 months), 60% of patients after an HLHS repair (21 +/- 15; range, 3.7-62.4 months) and 50% after a P-A anastomosis (27 +/- 21; range, 2.6-89.4 months). Only eight patients had more than trivial/mild regurgitation. No neoaortic stenosis was observed. Minor preoperative valve abnormalities did not influence postoperative valve function. Prior PAB placement significantly increased the likelihood of postoperative neoaortic regurgitation after a two-stage ASO but not after a P-A anastomosis. In the ASO group, patients with an intact ventricular septum had a significantly higher prevalence of neoaortic regurgitation than those with a ventricular septal defect.(ABSTRACT TRUNCATED AT 250 WORDS)

Anomalous origin of the left coronary artery from the pulmonary trunk (ALCA) remains a diagnostic as well as a therapeutic problem. The purposes of this study were: (1) to analyze left ventricular mechanics, including regional wall motion, in infants with ALCA, (2) to determine if the pattern of wall motion in infants with ALCA distinguishes these patients from those with congestive cardiomyopathy of other causes, and (3) to evaluate the potential for recovery of left ventricular function after successful restoration of a dual coronary artery system. Left ventricular mechanics were studied before and serially after surgery in six infants (2 to 13 months old) with ALCA. Fifteen age-matched normal subjects and seven age-matched patients with idiopathic congestive cardiomyopathy were also studied for comparison. Preoperatively, the end-diastolic volume in infants with ALCA was about four times larger than normal and did not differ from that in infants with CM; the myocardial volume was also about three times larger than normal, similar to that in the patients with CM. The myocardial volume/end-diastolic volume ratio was extremely low in patients with ALCA and in those with CM. The infants with ALCA did not exhibit specific segmental wall motion abnormalities but rather had global hypokinesis indistinguishable from that in the patients with CM. After successful repair, end-diastolic volume index rapidly decreased, reaching near normal values by 7 to 22 months after surgery, while myocardial volume index decreased at a slower rate, leading to an early phase of "overshoot hypertrophy," but reaching normal values by 7 to 22 months after surgery.+