Pediatric cardiac care consortium. Demonstrated value of a physician-directed quality assessment system.

A quality assessment system for analyzing the results of inpatient care of children with cardiac abnormalities is described. Three Minnesota institutions (the Mayo Clinic, Minneapolis Children's Medical Center, and the University of Minnesota) participate with 15 other similar centers elsewhere in the United States in this system. Patient data are analyzed and adjusted for case mix to allow for differences in patient populations and referral patterns. The statistical methods used are shown for two conditions: ventricular septal defect and aortic valvotomy. Data presented show reduction in length of stay for cardiac catheterization. This change occurred as physicians annually reviewed and discussed the data and, as a result, instituted changes. This physician-directed program seeks improvement in patient care through physician education.

Use of Doppler techniques (continuous-wave, pulsed-wave, and color flow imaging) in the noninvasive hemodynamic assessment of congenital heart disease.

Doppler echocardiography is a relatively new technique that has become an integral part of the cardiovascular ultrasound examination. The hemodynamic information provided by the Doppler technique is complementary to the tomographic anatomy depicted by the two-dimensional examination and, in some patients, may obviate the need for cardiac catheterization. In this article, we focus on the role of Doppler echocardiography in the noninvasive diagnosis of congenital cardiac abnormalities.

Continuous-wave Doppler echocardiographic assessment of severity of calcific aortic stenosis: a simultaneous Doppler-catheter correlative study in 100 adult patients.

Studies of the correlation of aortic valve gradient determined by continuous-wave Doppler echocardiography and that determined at catheterization have, to date, involved young patients and nonsimultaneous measurements. We therefore obtained simultaneous Doppler echocardiographic and catheter measurements of pressure gradient in 100 consecutive adults (mean age 69, range 50 to 89 years). In 63 patients pressure measurements were obtained with dual-catheter techniques and in 37 they were obtained by withdrawal of the catheter from the left ventricle to the ascending aorta. Forty-six of these patients also underwent an outpatient Doppler study 7 days or less before catheterization. The simultaneous pressure waveforms and Doppler spectral velocity profiles were digitized at 10 msec intervals and maximum, mean, and instantaneous gradients (mm Hg) were derived for each. The correlation between the Doppler-determined gradient and the simultaneously measured maximum catheter gradient was r = .92 (SEE = 15 mm Hg), that between the Doppler-determined and mean catheter gradient was r = .93 (SEE = 10 mm Hg), and that between the Doppler and peak-to-peak catheter gradient was r = .91 (SEE = 14). The correlation between the nonsimultaneously Doppler-determined gradient and the maximum gradient measured by catheter was not as strong (r = .79, SEE = 24). The continuous-wave Doppler echocardiographic velocity profile represents the instantaneous transaortic pressure gradient throughout the cardiac cycle. The best correlation with continuous-wave Doppler-determined gradient was obtained with maximum and mean gradients measured by catheter. Continuous-wave Doppler echocardiography can be used to reliably predict the pressure gradient in adults with calcific aortic stenosis.

Anatomy and function of the heart and intrathoracic vessels in congenital heart disease: evaluation with the Dynamic Spatial Reconstructor.

The Dynamic Spatial Reconstructor is a unique high speed volume imaging X-ray scanner based on computed tomographic principles. It has several potential advantages over conventional angiographic methods, including reduced invasion, reduced rate of false negative results and increased accuracy of measurements of structure and function. To evaluate the utility of the Dynamic Spatial Reconstructor in the investigation of congenital heart disease, scanning was performed in several pediatric patients with pulmonary valve atresia. Early results show that three-dimensional images of the cardiac chambers and intrathoracic vessels can be acquired and displayed with the system. All the information necessary for quantitative analysis of the pulmonary arteries can be obtained with a single scan involving injection of 0.6 to 2.0 cc/kg of contrast agent and radiation exposure of 0.54 to 0.95 rad/s over 5 to 8 seconds.

Functional assessment of the Fontan operation: combined M-mode, two-dimensional and Doppler echocardiographic studies.

Combined M-mode, two-dimensional and Doppler echocardiographic studies were used to assess the postoperative status of 33 patients who had undergone the modified Fontan procedure. Twenty-four patients had surgical repair with use of a simple direct right atrium to pulmonary artery anastomosis. The remaining patients had repair with use of a prosthesis or associated Glenn shunt. Twenty-seven patients were studied early in the postoperative period (2 months or less) and the remaining patients were studied up to 6 years postoperatively. A total of 36 examinations were performed. Of the 33 patients, 13 had tricuspid atresia, 12 had double inlet left ventricle with hypoplastic right ventricular outlet chamber and 8 had complex lesions with atrioventricular canal, double outlet right ventricle or a hypoplastic ventricle. Postoperative assessment by M-mode and two-dimensional echocardiography demonstrated normal or mildly reduced ventricular function (ejection fraction greater than 40%) in 22 patients. In 24 patients, a "normal" flow pattern was observed in the pulmonary artery by pulsed Doppler echocardiography, with predominant diastolic flow and accentuation by atrial systole somewhat similar to the venous flow pattern observed in the superior vena cava. "Abnormal" flow patterns (disorganized systolic flow, absence of atrial waves and little or no increase with inspiration) were observed in nine patients with reduced ventricular function or residual shunt. Continuous wave Doppler study also demonstrated mild dynamic subaortic obstruction in two patients. Combined pulsed and continuous wave studies showed atrioventricular valve insufficiency in 10 patients. Follow-up studies revealed a satisfactory clinical course in most patients. Three patients died approximately 4 to 8 months after their Fontan operation.

Two-dimensional echocardiographic assessment of normal fetal cardiac anatomy.

The fetal heart is visualized routinely during the antepartum ultrasound examination. Because of the advent of high-resolution, real-time ultrasound instruments, details of fetal cardiac anatomy can now be defined. Fifty consecutive fetuses were examined in utero to assess the ability of two-dimensional echocardiography to define intracardiac anatomy at various gestational ages. A complete examination required at least three standard echocardiographic views of the heart: four-chamber, short-axis and long-axis views. In 30 of the 50 fetuses studied (60%) only one examination was necessary to obtain this information. Ten patients had a second examination later in gestation that complemented the findings of their first study. In all but two fetuses, detection of all four cardiac chambers and at least one semilunar valve was possible. Mitral-semilunar valve continuity was detected in all. The quality of echocardiographic imaging was enhanced by the fetal occiput posterior position (three views obtained in 83% of the fetuses studied). Breech position did not affect imaging quality. Prior to 30 weeks of gestation, fetal movement hampered analysis of fetal cardiac anatomy in some patients.

Two-dimensional echocardiographic spectrum of Ebstein's anomaly: detailed anatomic assessment.

This report details the two-dimensional echocardiographic assessment of 41 patients with Ebstein's anomaly. The anatomic spectrum of Ebstein's anomaly is correlated with surgical and autopsy observations in 66% of these patients. Morphologic abnormalities of the tricuspid valve and right heart structures were uniquely assessed by noninvasive two-dimensional echocardiographic examination. Features of the tricuspid valve that best related to decreased functional capacity were: 1) absence of the septal leaflet, and 2) pronounced tethering, restriction of motion and displacement of the anterior leaflet of the tricuspid valve. This 4 1/2 year experience suggests that two-dimensional echocardiography can replace angiography as the procedure of choice for diagnostic and morphologic assessment of Ebstein's anomaly. Cardiac catheterization is necessary only when specific hemodynamic questions or clinical inconsistencies exist.

Two-dimensional echocardiographic assessment of dextrocardia: a segmental approach.

Two-dimensional echocardiography was used in the prospective evaluation of 40 patients with the clinical diagnosis of dextrocardia. A segmental analysis of the situs, connections, ventricular anatomy, and chamber positions was utilized for a complete diagnostic assessment. An adequate examination was possible in 33 of these patients; the findings were confirmed by cardiac catheterization and angiography in 31 patients and at operation in 26. Use of the location of the liver and the drainage of the hepatic veins and inferior vena cava allowed atrial visceral situs to be defined in 33 patients (solitus 21, inversus 9, and ambiguous 3). Pulmonary venous connections were correctly identified in 27. In 33 patients, atrioventricular (AV) and ventriculoarterial connections and ventricular anatomy were correctly predicted. Twenty patients had 2 separate well-developed ventricles. Ventriculoarterial connections were determined correctly in all 20 patients: concordant in 5, discordant in 6, double-outlet right ventricle in 5, and single-outlet right ventricle (pulmonary atresia) in 4. In 16 patients a ventricular septal defect was correctly identified. In the remainder the ventricular septum was intact. Thirteen patients had univentricular heart: 8 had 2 AV valves (double-inlet ventricle) 3 had common AV inlet, and 2 had atresia of 1 AV connection. Two-dimensional echocardiography allowed the accurate assessment of complex congenital heart defects associated with dextrocardia. Utilizing a segmental approach, one can correctly predict atrial-visceral situs, ventricular morphology and situs, and AV and ventriculoarterial connections.

Atrioventricular and ventriculoarterial discordance (corrected transposition of the great arteries). Wide-angle two-dimensional echocardiographic assessment of ventricular morphology.

Wide-angle two-dimensional echocardiography was used to establish criteria for recognition of ventricular situs and ventricular morphology in 27 patients (ages 2 month to 58 years) with atrioventricular amd ventriculoarterial discordance (corrected transposition of the great arteries). The morphologic left ventricle was recognized by the presence of an atrioventricular valve that was attached more superiorly along the ventricular septum than the other atrioventricular valve, that had a fish-mouth (bicommissural) appearance in diastole, and that had two discrete papillary muscles; by a ventricle with a finely trabecular pattern and ellipsoid shape; and by the presence of direct continuity between the atrioventricular and semilunar valves. The morphologic right ventricle was recognized by the presence of an atrioventricular valve that was attached more inferiorly along the ventricular septum, that had a triangular (tricommissural) appearance, and that had multiple irregular papillary muscles; by a ventricle with a coarsely trabecular pattern and a triangular or crescentic shape, and by the presence of muscular atrioventricular-semilunar valve discontinuity. Using these criteria, ventricular situs and morphology could be reliably determined by noninvasive two-dimensional echocardiography. In addition, two-dimensional echocardiography allowed the recognition of frequently associated anomalies. In this series, two-dimensional echocardiography demonstrated Ebsteins's malformation of the left atrioventricular valve in four patients and a straddling atrioventricular valve in eight (one right-sided, seven left-sided.

Clinical, angiographic, and hemodynamic assessment of late results after Mustard operation.

Since 1974, late results of the Mustard procedure for correcting complete transposition of the great arteries have been evaluated by cardiac catheterization, electrocardiography, roentgenography, history, and physical examination of 48 Mayo Clinic patients. Of these, 15 were studied 1 month to 2 years postoperatively because of clinical deterioration. The other 33 had been asymptomatic but were asked to return for hemodynamic reevaluation one-half to 11 years postoperatively. Of the asymptomatic group, 19 underwent exercise electrocardiography prior to catheterization and eight performed supine exercise during catheterization. Cardiac catheterization proved the most effective mode of study. Significant cardiovascular abnormalities (caval obstruction, residual pulmonary stenosis, etc.) were found in 35 of the 47 patients--including 20 of the 33 who were asymptomatic. Eight of the symptomatic group and three of the others have died since this restudy. These poor results warrant renewed effort to devise better methods for correcting complete transposition,