Daniel J. Murphy

Continuous-wave Doppler in children with ventricular septal defect: Noninvasive estimation of interventricular pressure gradient

Continuous-wave Doppler was used to estimate the pressure gradient between the right and left ventricles in 28 children with ventricular septal defect (VSD). Doppler measurement of maximal velocity was performed during cardiac catheterization and the Doppler-predicted gradient was compared with the peak-to-peak gradient measured simultaneously by catheter. Doppler gradients ranged from 10 to 71 mm Hg and correlated well with measured gradient (r = 0.97, p greater than or equal to 0.001). Fourteen patients had isolated VSD, and in these patients Doppler measurements of gradient allowed accurate estimation of right ventricular pressure (r = 0.93). There was an inverse correlation between the ratio of pulmonary to systemic resistance and maximal velocity (r = -0.77). Thus, continuous-wave Doppler is an accurate means of measuring instantaneous VSD pressure gradient in children with congenital heart disease and can be used to estimate the right ventricular and pulmonary artery pressure in children with isolated VSD. This noninvasive method can be used to distinguish restrictive from nonrestrictive VSD.

Results of balloon valvuloplasty in typical and dysplastic pulmonary valve stenosis: Doppler echocardiographic follow-up

To assess the usefulness of balloon valvuloplasty in patients with a dysplastic pulmonary valve, the files of 36 patients (aged 1 day to 18.5 years) who had two-dimensional echocardiography before and continuous wave Doppler echocardiography late after balloon valvuloplasty (balloon diameter greater than or equal to 20% anulus diameter) were reviewed. Results of relief of pulmonary stenosis were graded by catheter gradient in the catheterization laboratory and compared with Doppler echocardiographic findings at follow-up. There were 32 patients with typical pulmonary stenosis and 4 with a dysplastic valve. In the 32 patients with typical pulmonary stenosis, transvalvular gradient changed from a mean of 67 +/- 32 to 20 +/- 20 mm Hg (p less than 0.0001, mean reduction 72.6%). The gradients at follow-up by Doppler echocardiography averaged 20 mm Hg including 15 that increased, 3 that were unchanged and 14 that decreased. Only 3 (9%) of 32 patients had a gradient greater than 25 mm Hg at follow-up and only one gradient was greater than 35 mm Hg. All four patients with a dysplastic valve had a gradient that decreased with valvuloplasty from a mean of 85 +/- 33 to 33 +/- 20 mm Hg (p less than 0.05); gradient reduction in this group ranged from 40 to 85% (mean 57.5%). The gradient at follow-up increased in three of these four patients and decreased in one (the only late gradient less than 25 mm Hg). Late gradient was less than 35 mm Hg in two of the four patients and was reduced by 43 and 57%, respectively, in the other two.(ABSTRACT TRUNCATED AT 250 WORDS)

Detection of diastolic atrioventricular valvular regurgitation by pulsed Doppler echocardiography and its association with complete heart block

Abstract The cineangiographic and hemodynamic presence of diastolic mitral regurgitation has been described in patients with complete heart block, aortic valvular regurgitation, hypertrophic cardiomyopathy, and in patients with long diastolic filling periods in atrial fibrillation. 1–3 However, because of its relatively low velocity, diastolic mitral regurgitation may be difficult to diagnose noninvasively. Pulsed Doppler echocardiography provides noninvasive evaluation of blood flow through cardiac valves and has been shown to be sensitive in the detection of valvular regurgitation. 4,5 We studied 8 consecutive, nonselected patients with complete heart block over a 6-month period, and all had Doppler evidence of diastolic mitral or tricuspid regurgitation.

Reduced mortality in small premature infants treated at birth with a single dose of synthetic surfactant

A randomized controlled trial of Exosurf® Neonatal, a synthetic exogenous surfactant, was performed. Exosurf was given to premature infants weighing 700‐1350 g, by instillation down the endotracheal tube during mechanical ventilation, within 1 h of birth. Control infants were treated with air. Dose administration was performed in secrecy by clinicians who maintained the blind for 2 years. A total of 109 infants received air and 109 received Exosurf; 19 infants with congenital pneumonia or major malformations were excluded from the primary efficacy analysis. By the age of 28 days there were 14 deaths in the air group and 4 deaths in the Exosurf group, a 69% reduction with Exosurf (P= 0.050). Survival without bronchopulmonary dysplasia at the age of 28 days was significantly improved by 15% (P= 0.050). By the age of 1 year post‐term there were 19 deaths in the air group and 10 deaths in the Exosurf group, a 42% reduction with Exosurf (P = 0.104). There were no significant changes in the incidence of bronchopulmonary dysplasia, pulmonary air leaks, intraventricular haemorrhage, patent ductus arteriosus, necrotizing enterocolitis or infection. The reduction in mortality indicates important results in high risk premature infants treated soon after birth with a single dose of Exosurf.

Evaluation of Coronary Artery Fistula by Color‐Flow Doppler Echocardiography

An asymptomatic newborn infant with a left coronary artery to right ventricular apex fistula was evaluated using color‐flow Doppler techniques. Color flow mapping during diastole showed a prominent turbulent flow signal that could be traced from the proximal left coronary artery, along the interventricular septum, to the right ventricular apex. Color flow Doppler is an important complement to two‐dimensional imaging for the identification and location of coronary artery fistulas.

Small Bowel Obstruction as a Complication of Kawasaki Disease

A case of small bowel obstruction in an 8-month-old infant with Kawasaki disease is described. At laparotomy a discrete area of jejunal stricture with adhesions was noted. Microscopic examination revealed evidence of small artery thrombosis. Kawasaki disease results in a diffuse vasculitis, which may produce significant abnormalities in multiple organ systems. Serious abdominal complications can occur and should be considered when gastrointestinal symptoms develop in a patient with Kawasaki disease.

Intracardiac undifferentiated sarcoma in infancy

A rare case of an intracardiac undifferentiated sarcoma in a 3 month old infant is described together with the clinical, angiographic, echocardiographic, surgical and histopathologic findings. The tumor was successfully removed surgically, and monthly echocardiographic follow-up is being performed.

Doppler Echocardiography in Pulmonary Stenosis

Doppler ultrasound has dramatically improved the accuracy of noninvasive detection of pulmonary stenosis. Combined with careful two‐dimensional imaging, the site and severity of obstruction to pulmonary flow can be detected and quantified. Although there are some limitations to the technique, interpretive errors are avoidable with an understanding of the method and careful attention to detail during the performance of the examination. Doppler echocardiography has become a valuable adjunct to the nonsurgical treatment of valvular pulmonary stenosis and promises to provide more information for developing new management schemes in congenital heart disease.

Surgery without angiography for neonates with aortic arch obstruction

Traditional diagnostic assessment of the neonate and infant with congenital abnormalities of the aorta causing left ventricular outflow tract obstruction has required catheterization and angiography. However, these patients frequently present critically ill and invasive diagnostic procedures may be associated with significant risks. Two-dimensional echocardiography has been used for aiding diagnosis of aortic arch abnormalities, but there has been little information concerning its use as the definitive imaging technique for preoperative assessment. We reviewed neonates who required urgent surgery for congenital obstruction of the aorta. The diagnosis was made using two-dimensional echocardiographic imaging and Doppler techniques for hemodynamic assessment in lieu of catheterization and angiography in all. Anatomic detail provided by the noninvasive approach was both sensitive and specific in guiding surgery in all but one case. We conclude that echocardiography eliminates the need for invasive preoperative diagnostic procedures in selected neonates with congenital aortic arch obstruction.

Usefulness of color-flow Doppler in diagnosing and in differentiating supracristal ventricular septal defect from right ventricular outflow tract obstruction

Color-flow Doppler is used for special localization of cardiac flows. The transeptal jet in supracristal ventricular septal defect (VSD) is directed toward the pulmonary valve and is often difficult to distinguish from the right ventricular (RV) outflow tract flow. Pulsed- and continuous-wave Doppler can misread the VSD jet as a stenotic lesion in the RV outflow tract. This study describes the color-flow Doppler characteristics of supracristal VSD and determines if color-flow Doppler can differentiate supracristal VSD jets from RV outflow tract flow. The study group comprised 28 patients ranging in age from 3 days to 23 years (mean 6.4), with catheter-diagnosed supracristal VSD in 14, isolated pulmonary valve stenosis in 10 and RV infundibular obstruction in 4. The echocardiographic Doppler and color-flow Doppler data of all patients were reviewed without knowledge of catheterization diagnosis. In all patients with supracristal VSD, color-flow Doppler revealed an abnormal transeptal jet directed toward the pulmonary valve that occurred 5 to 10 ms before RV outflow tract flow was identified. VSD and RV outflow tract jet could be differentiated by pulsed- and continuous-wave Doppler alone in 10 of 14 patients (71%). In 4 patients, differentiation was possible only with color-flow Doppler and electrocardiographic gating. Associated aortic regurgitation, or a fistula, or both, were detected in 6 patients. Pulsed- and continuous-wave Doppler with or without color-flow Doppler correctly identified the level of obstruction in all patients with RV outflow tract lesions (14 of 14). Supracristal VSD jet occurs in early systole and is directed toward the pulmonary valve.(ABSTRACT TRUNCATED AT 250 WORDS)