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Two-dimensional and Doppler echocardiography were compared with cardiac catheterization and angiography in the preoperative evaluation of ostium primum atrial septal defect. Preoperative echocardiographic examinations as well as operative reports of all patients (33 patients aged 2 months to 23 years at surgery) with ostium primum atrial septal defect or transitional atrioventricular (AV) canal defect having had echocardiography and surgical repair at The Children's Hospital, Boston from July 1983 to January 1986 were retrospectively reviewed. Original cardiac catheterization and angiographic reports also were reviewed. Preoperative echocardiography resulted in no false positive or false negative primary diagnoses when compared with the diagnoses obtained at preoperative angiography or surgery. Doppler assessment of mitral regurgitation correlated well with angiographic (93% agreement) and intraoperative (85% agreement) assessments of mitral regurgitation to within two diagnostic categories on the six level scoring system used. There was reasonably good agreement between the two-dimensional echocardiographic estimate of right ventricular systolic pressure and that measured at catheterization when expressed as percent of the simultaneous left ventricular pressure. Seven of nine ventricular septal defects observed intraoperatively were noted on preoperative echocardiography; five of these defects were detected on preoperative angiography. A variety of other surgically confirmed associated cardiovascular defects were observed by both preoperative techniques. However, echocardiography appeared to be superior to angiography for evaluation of AV valve morphology and papillary muscle architecture. This study implies that in children with typical clinical and two-dimensional echocardiographic and Doppler findings for ostium primum atrial septal defect or transitional AV canal defect, routine preoperative cardiac catheterization and angiography are unnecessary.

Validation of a totally noninvasive method for estimating instantaneous left ventricular pressure and constructing a pressure waveform throughout ejection in patients with aortic stenosis is reported. In 20 patients (aged 8.75 +/- 10 years) with congenital aortic stenosis (measured peak left ventricular pressure 120 to 260 mm Hg; transvalvular gradient 18 to 165 mm Hg), transaortic valve continuous wave Doppler ultrasound, indirect carotid pulse tracing, peripheral blood pressure and measured left ventricular pressure were recorded simultaneously at cardiac catheterization. Data were entered into a microcomputer using a digitizing tablet and the instantaneous Doppler gradient was calculated and added to instantaneous aortic pressure, derived from the time-corrected and calibrated carotid pulse tracing, to estimate instantaneous left ventricular pressure. Estimated left ventricular pressure waveforms reproduced measured left ventricular pressure closely. The mean error at peak left ventricular pressure was 0.2 +/- 4.8 mm Hg (r = 0.98, p = 0.001). The average error throughout ejection was 0.9 +/- 5.1 mm Hg. The error of estimated pressure was not related to age or the severity of aortic stenosis. The Doppler peak instantaneous gradient was observed to correlate closely (r = 0.97, p = 0.001) with peak to peak gradient. With this technique, the left ventricular pressure waveform throughout ejection can be accurately estimated noninvasively in patients with aortic stenosis. This methodology enables determination of mean, total and instantaneous systolic left ventricular pressure.

Anomalous connection of a coronary artery to a ventricle or pulmonary artery causes shunting of blood from the coronary circuit and may produce myocardial ischemia. Such a coronary anomaly may occur in isolation or with other defects. Doppler color flow mapping and two-dimensional echocardiography were used to diagnose anomalous coronary connections in 13 patients, 1 day to 7 years of age, over a 1 year period. The diagnoses were anomalous origin of the left coronary artery from the pulmonary trunk in five patients, a coronary artery to left ventricle fistula or coronary artery to pulmonary artery fistula in four patients with other complex defects, right ventricular sinusoids in two patients with pulmonary atresia and intact ventricular septum and an isolated coronary artery fistula in two patients. In all cases, the abnormal coronary connection was recognized on the basis of an abnormal, continuous or to and fro flow pattern in the fistula and its connections as demonstrated by scanning in multiple views with Doppler color flow mapping. The low spatial resolution of Doppler color flow mapping limits the anatomic detail available; nonetheless, it is a significant advance in the noninvasive diagnosis of abnormal coronary connections.

Physiologic hypertrophy resulting from intense athletic participation has been reported to result in normal, reduced and augmented overall left ventricular performance. Rather than representing true differences in left ventricular contractility, these data may reflect the variable degree of ventricular dilation and increased wall thickness that occur with different types of exercise. As such, the resultant altered loading conditions may diminish the ability of the usual indexes of left ventricular function to accurately assess the left ventricular contractile state. Therefore, three groups of elite athletes with distinct patterns of myocardial hypertrophy were investigated utilizing recently developed load-independent contractility indexes. Age-matched control subjects (n = 33) were compared with 11 swimmers, 11 long-distance runners and 11 power lifters. Rest echocardiogram, phonocardiogram and calibrated carotid pulse tracing were used to calculate left ventricular dimensions, wall thickness, mass, fractional shortening, velocity of shortening and mean, peak and end-systolic wall stresses and the stress-time and minute stress-time integrals. Compared with control subjects, all athletes had increased left ventricular mass, even when values were normalized for body surface area. Runners had a dilated left ventricular and normal wall thickness, swimmers had a mildly dilated ventricle with increased wall thickness and power lifters had normal cavity size with markedly increased wall thickness. Peak systolic wall stress was normal in runners and swimmers and reduced in power lifters, whereas end-systolic stress was low in swimmers and power lifters and normal in runners. The minute stress-time integral, a measure of myocardial oxygen consumption, was normal in runners and swimmers but was significantly reduced in lifters.(ABSTRACT TRUNCATED AT 250 WORDS)

Nine infants with episodic or continuous chaotic atrial rhythm (CAR) are presented. In addition to 3 or more different P-wave contours, atrial rates greater than 100 per minute, variable PP, RR, and PR intervals, and a discrete isoelectric baseline, findings included atrial rates that varied from a low of 50 to 120 to a high of 140 to 270 per minute, ventricular rates that varied from a low of 40 to 50 to a high of 180 to 270 per minute, and periodic sinus arrest with junctional escape rhythm. Except for the arrhythmia, all had a normal cardiac examination, ECG, chest x-ray film, and echocardiogram. Six infants were otherwise normal; one had an orbital rhabdomyosarcoma; one had neonatal asphyxia; and one had respiratory distress, bronchopulmonary dysplasia, and an intraventricular cerebral hemorrhage. The CAR persisted from 3 days to 20 months; it spontaneously reverted to normal sinus rhythm in 8 infants and persists in 1 infant at age 7 months. Digoxin (4 patients), propranolol hydrochloride (3 patients), quinidine sulfate (2 patients), and lidocaine (1 patient) did not alter the CAR. No patient had heart failure secondary to the CAR, although three also had episodes of sustained atrial tachycardia, which while present caused heart failure. All patients are functioning normally at home and have normal findings on cardiac examination and have normal ECGs at ages 3 to 38 months. Seven are in normal sinus rhythm, one has rare atrial premature contractions, and one has persistent CAR. We conclude that specific treatment was not necessary in these infants with CAR, except in those with associated sustained atrial tachycardia, which itself may cause heart failure.

Although the left ventricular (LV) end-systolic pressure-dimension relation is a load-independent, sensitive index of contractile state, its accurate determination requires afterload manipulation. The slope value of the late-systolic stress-dimension relation determined under resting conditions has been suggested as an alternative index of contractility that can be assessed without pharmacologic intervention. To evaluate this relation, 14 normal subjects were studied by M-mode echocardiography, phonocardiography and indirect carotid pulse tracings during infusion of methoxamine to increase afterload. Seven of these subjects were also studied after infusion of dobutamine to increase contractility. Continuous systolic stress-dimension trajectories were computer generated from digitized tracings. The late-systolic portions of these curves were found to be linear and the slope and intercept were determined. The slope value was sensitive to both afterload and contractility, and the magnitude of change in slope value was relatively greater during afterload enhancement than during inotropic stimulation. A strong correlation of slope value with peak systolic stress was found. Thus, the late-systolic stress-dimension relation is linear with a slope value which is dependent on both LV contractility and afterload. Like other ejection phase indexes, the usefulness of this index is limited by its inability to distinguish changes in contractile state from alterations in loading conditions.

We compared the cardiac index obtained by means of a continuous-wave Doppler computer with simultaneous thermodilution measurements in 25 children in the pediatric intensive care unit (40 observations). The aortic diameter was measured at various levels to determine which provided the best measure of cardiac index. The Doppler measurements were performed independently by a physician trained in Doppler cardiography and by a nurse with no experience in echocardiography. Both the nurse and physician obtained high-quality flow velocity recordings in all patients in a mean time of 5 minutes or less. Cardiac index and total systemic vascular resistance measured by means of Doppler and thermodilution techniques were highly correlated (r = 0.86 and r = 0.93, respectively). The highest correlation was obtained when Doppler cardiac index was computed by means of the internal diameter measured at the aortic anulus. There was no significant difference between the nurse's and physician's measurements. We conclude that cardiac index can be accurately determined in the pediatric intensive care unit by means of continuous-wave Doppler computer, even when operated by personnel not trained in Doppler cardiography.

Critical pulmonary stenosis or atresia with intact ventricular septum represents a congenital cardiac lesion for which the long-term prognosis appears to depend partly on the size of the right ventricle. Thus, the capability of noninvasive assessment of right ventricular size to predict operative outcome was examined in 15 infants (aged 1 to 30 days, mean 5.6) with severe right ventricular outflow tract obstruction (either critical pulmonary stenosis [7 patients] or pulmonary atresia with intact ventricular septum [8 patients]). Using echocardiography in two orthogonal subxiphoid views, right ventricular volume, wall thickness, area change fraction, ejection fraction and tricuspid anulus dimension were measured. All patients with a normalized right ventricular enddiastolic volume of less than 5 ml/m2 and a normalized tricuspid anulus dimension of less than 1.0 cm/m2/3 required a shunt operation. Only one patient with a volume of more than 6 ml/m2 and a normalized tricuspid anulus dimension of more than 1.4 cm/m2/3 required more than relief of right ventricular outflow tract obstruction. In this patient, residual severe pulmonary stenosis necessitated the shunt procedure. One patient with a volume of more than 6 ml/m2 had an anulus diameter of less than 1.4 cm/m2/3 and one patient with an anulus diameter of more than 1.4 cm/m2/3 had a volume of less than 6 ml/m2; both required shunt procedures. It therefore appears that if either the ventricular volume or tricuspid anulus size is excessively small, a shunt procedure is necessary. Wall thickness, area change fraction and ejection fraction measurements were not significantly correlated with right ventricular volume or postoperative outcome.(ABSTRACT TRUNCATED AT 250 WORDS)

The influence of changes in preload, afterload and contractile state on left ventricular (LV) filling characteristics were examined. Normal subjects underwent echocardiographic determination of the peak rates of LV dimension change and wall thinning and their respective timing at rest, after preload augmentation with dextran, during increased afterload with methoxamine and during inotropic stimulation by dobutamine. These 2 peak velocities and their timing in diastole correlated well with each other and responded similarly to interventions. Increased preload resulted in higher peak velocities of dimension change and wall thinning, without changing the time in diastole at which they occur. Both peak velocities moved later into diastole with higher afterload; however, the overall change in magnitude was variable and without statistical significance. Inotropic stimulation resulted in faster rates of peak dimension change and wall thinning, which occurred at an earlier point in diastole. Examination of various measures of LV size and function over a wide range of preload and afterload conditions under a constant contractile state revealed a complex set of relations. The ratio of wall thickness-to-dimension at end-diastole showed the most significant relation to the peak rate of dimension change, whereas peak thinning was best correlated with fractional wall thickening. Both velocities were also significantly but more weakly related to other variables of systolic function. The timing of these peak velocities correlated most closely with the end-systolic wall stress and heart rate. Thus, LV filling and wall thinning depend in a complex fashion on loading conditions, heart rate and contractile state.(ABSTRACT TRUNCATED AT 250 WORDS)