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Biomedical subjects

J G Stevenson

Publications and source records attributed to J G Stevenson.

At least 73 records · Page 4Linked to original sources
PubMed1980

Pulsed Doppler echocardiographic diagnosis of patent ductus arteriosus: sensitivity, specificity, limitations, and technical features.

To determine the diagnostic features, sensitivity, and specificity of pulsed Doppler echocardiographic (PDE) diagnosis of patent ductus arteriosus (PDA), 110 infants with heart disease were examined by PDE from the precordial and suprasternal notch approaches. On precordial examination, PDA was diagnosed upon recording of diastolic ductal flow into the pulmonary artery. From the suprasternal approach, PDA was suspected upon recording of continuous turbulent flow in the right pulmonary artery. A PDA was proved by invasive means in 45 of 110 cases. Precordial PDE had diagnosed PDA in 43 of 45 cases. In eight of 110, continuous turbulent flow was present in the pulmonary artery from the precordial approach, but no PDA jet was recorded. In two of eight, PDA was present, and in six of eight others systemic-to-pulmonic communications were present. Precordial PDE diagnosis of PDA had a sensitivity of 96%, specificity of 100%, positive predictive index of 100%, and negative predictive index of 97%. From the suprasternal notch approach, PDA was suspected in 51 cases, with six false-positive diagnoses, yielding a sensitivity of 100%, specificity of 91%, positive predictive index of 88%, and negative predictive index of 100%. Since the diastolic ductal jet flowing into the pulmonary artery was specific for PDA in all patients in whom it was recorded from a precordial approach, that approach and diagnostic feature, with sensitivity and positive predictive index of 100%, would seem preferred for PDE diagnosis of PDA. This would be especially important if the PDE diagnosis of PDA were to be used in place of invasive documentation of PDA, and in the differential diagnosis of PDA and other systemic-to-pulmonic communications. The suprasternal approach, while not specific for PDA, may have the advantage of sensitive detection or exclusion of a variety of systemic-to-pulmonic communications.

Adolescent↗
PubMed1980

Evaluation of ejection murmurs by pulsed Doppler echocardiography.

A common problem is a soft basal ejection murmur in an asymptomatic child with a normal electrocardiogram and chest x-ray films. If the diagnosis is aortic stenosis, there is a need for prophylaxis for subacute bacterial endocarditis and concern about development of calcific aortic stenosis. In 40 consecutive children referred for this differential diagnosis, aortic stenosis was diagnosed in 30, based on an ejection murmur at the second right interspace (not necessarily louder than at the second left), which transmitted well to the neck, accompanied by a normal second heart sound. Pulsed Doppler echocardiography confirmed turbulence at the aortic valve in 26. In the 10 children diagnosed clinically as having an innocent murmur, three had evidence on pulsed Doppler echocardiography for an abnormal aortic valve. The conventional echocardiographic findings of an eccentric aortic orifice were present in only 21 of 29 patients with aortic turbulence. Though our current clinical criteria are reasonably specific (87%), they are not as sensitive (70%). Pulsed Doppler echocardiography provides powerful non-invasive assistance for this important differential diagnosis.

Adolescent↗
PubMed1980

Prognosis in primary ventricular tachycardia in the pediatric patient.

Five male pediatric patients with primary ventricular tachycardia are described. Although three were initially in congestive heart failure due to the tachycardia and were extremely difficult to manage, all have completely recovered, are not taking medication, and are free of arrhythmia. Three of the patients required long-term management with quinidine, with a therapeutic goal of controlling the heart rather than abolishing the arrhythmia. No growth disturbances were found in those three patients. A review of reported cases revealed 71 infants and children with ventricular tachycardia not associated with heart disease or systemic disorders; only four deaths were reported (5.6%). In the primary form of ventricular tachycardia in children, complete pharmacologic suppression may not be achieved without seriously endangering the normal electrophysiologic functions. Controlling the rate to an asymptomatic level with pharmacologic means is safer for a problem that may be self-limited.

Child↗
PubMed1979

The significance of carotid bruits in children: transmitted murmur or vascular origin, studies by pulsed Doppler ultrasound.

Forty-four youngsters with precordial murmurs and carotid bruits were evaluated clinically and independently, using pulsed Doppler ultrasound. The precordial murmur was evaluated with M-mode echocardiography combined with Doppler flow evaluation, and the carotid bruit was evaluated with peripheral vascular sector scan with Doppler flow evaluation. These ultrasonic techniques can identify abnormal blood flow at anatomic sites such as the aortic valve and in the carotid arteries. The patients had no symptoms and their condition, except for six, was mild enough that catheterization was not indicated. The clinical diagnosis of aortic stenosis was made in 30 children, and nine were thought to have no heart disease. On the basis of the ultrasonic examinations, 28 patients were diagnosed as having aortic stenosis and seven subjects had no intracardiac turbulence. However, there was disagreement in 14 instances; four of the six clinical "normals" were found to have aortic stenosis by pulsed Doppler echocardiography; six patients diagnosed as having mild aortic stenosis on a clinical basis were found to have no aortic abnormality. The results confirm that aortic stenosis usually presents as a murmur maximal in the aortic area, which is associated with a carotid bruit. Unfortunately, in at least one-fourth of the cases the murmur was not maximal at the aortic area, and a carotid bruit was found in several normal subjects. Since the consequences of over- or under-diagnosis of aortic stenosis are substantial, careful thought should be given to the differential diagnosis, and if possible, pulsed Doppler echocardiography should be utilized for a definitive statement of aortic valve-induced turbulence.

Adolescent↗
PubMed1979

Pulsed Doppler echocardiographic detection of total anomalous pulmonary venous return: resolution of left atrial line.

During precatheterization M mode echocardiographic examination, 33 infants were identified as having findings including right ventricular enlargement and presence of a line within the left atrial portion of the M mode tracing suggesting the possibility of cor triatiatum or total anomalous pulmonary venous return. Pulsed Doppler echocardiography was used to sample blood characteristics on either side of the left atrial line to determine which line was artifactual and which was indicative of an important structure. Five patients whose blood flow characteristics were different on either side of the left atrial line were subsequently proved to have total anomalous pulmonary venous return at cardiac catheterization. In the remaining infants blood flow characteristics were identical on either side of the line, and catheterization excluded total anomalous pulmonary venous return and cor triatriatum. In all patients who had total anomalous pulmonary venous return, drainage involved a persistent left superior vena cava, and this vascular structure was identified by pulsed Doppler examination from the suprasternal notch. Pulsed Doppler echocardiography appears to be a useful technique for resolution of left atrial lines found on M mode echocardiography.

Cardiac Catheterization↗
PubMed1979

Pulmonary hypertension accompanying ventricular septal defect and patent ductus arteriosus. Management in infancy and early childhood.

Forty-one infants and children with the combination of patent ductus arteriosus (PDA) and ventricular septal defect (VSD) were encountered over 20 years. Twenty-four presented in infancy with congestive cardiac failure. Pulmonary hypertension was present in 32, the cause in 19 being increased pulmonary blood flow. Increased pulmonary vascular resistance (PVR) was detected in 13 (indicated by a pulmonary to systemic resistance ratio (Rp : RS) greater than 0.24:1 and PVR greater than 4 units). Thus 22% had a pulmonary artery systolic pressure less than 30 mmHg and 68% had a pulmonary vascular resistance below four units, indicating an unusually mild form of the combined condition in these patients. Surgical management is discussed, and in particular the question of simultaneous closure of the defects during infancy. Cardiac failure, resistant to drug treatment, and increased PVR are indications of operation. The PDA should be closed and only if there is no substantial fall in pulmonary artery pressure is the VSD repaired.

Child↗
PubMed1979

Noninvasive detection of pulmonary hypertension in patent ductus arteriosus by pulsed Doppler echocardiography.

Twenty-five patients with proven patent ductus arteriosus were examined by pulsed Doppler echocardiography (PDE) before invasive assessment. Ten patients had normal pulmonary artery pressures, and by PDE, pandiastolic ductal flow. Fifteen patients had elevation of mean pulmonary artery pressure, and by PDE, all had abbreviations of diastolic ductal flow. PDE correctly distinguished between patients with normal pressure and those with evidence of pulmonary hypertension; the ECG did not allow such differentiation. Detection by PDE of pulmonary hypertension complicating patent ductus arteriosus appears to be clinically useful.

Blood Pressure↗
PubMed1978

Relation of angina to coronary artery disease in mitral and in aortic valve disease.

Of 129 patients with either mitral or aortic valve disease angina was present in 55 (42%). It was more frequent in aortic (60%) than in mitral valve disease (33%). The standard 12-lead electrocardiogram was not helpful in distinguishing underlying occlusive coronary artery disease. Coronary arteriography demonstrated coronary artery disease in 26 patients (20%), only 2 of whom had no angina. The incidence of coronary artery disease was almost identical in both the mitral and aortic groups (22% and 17%, respectively), but the percentage of those with demonstrable coronary artery disease accompanying angina was much higher in the mitral group (67% as against 29%). Angina in mitral valve disorders is thus much more likely to be the result of disease of the coronary arteries. Coronary arteriography is mandatory in all patients in both groups who have angina. Otherwise it seems unnecessary as coronary artery disease was found in only 2 patients who did not have angina.

Adult↗
PubMed1978

Critical aortic stenosis in neonates.

Twelve infants with valvular aortic stenosis manifested symptoms of heart failure during the first 2 months of life. Nine became symptomatic and demonstrated cardiomegaly and pulmonary vascular congestion during the first week of life. The other 3 infants became symptomatic at 3-8 weeks. Echocardiograms revealed normal or enlarged left atrial and ventricular dimensions excluding hypoplastic left heart. Left ventriculography demonstrated segmental dysfunction in 7 infants and generalized hypokinesis in 2 others. Trabecular effacement corresponded with the sites of left ventricular dysfunction. Postoperative studies revealed a decrease in cardiac size and improvement in segmental dysfunction in most infants.

Aortic Valve Stenosis↗
PubMed1978

Diagnosis of ventricular septal defect by pulsed Doppler echocardiography. Sensitivity, specificity and limitations.

The M-mode echocardiographic findings of ventricular septal defect (VSD) are nonspecific. A specific pulsed Doppler echocardiographic (PDE) diagnosis of VSD can be made by following the turbulent VSD jet through the septum. To assess the sensitivity, specificity and limitations of PDE diagnosis of VSD, 105 children undergoing cardiac catheterization were examined by PDE. These children had a variety of cardiac defects, and a PDE diagnosis of VSD was made in 46/51 (90%) who had VSD proven at catheterization. There was one false positive PDE diagnosis of VSD, for a specificity of 98%. Factors influencing the ability to diagnose VSD by PDE include the location of the defect, level of pulmonary vascular resistance and direction of blood flow through the VSD. The presence of additional defects did not interfere with PDE diagnosis of VSD. The PDE detection of additional defects may identify situations where M-mode echocardiographic estimation of dimensions may not be indicative of the size of VSD shunt.

Adolescent↗
PubMed1977

Fluid administration in the association of patent ductus arteriosus complicating respiratory distress syndrome.

Daily weights and mean daily fluid volumes administered to 62 infants with birth weights of less than 2,000 gm, who required respiratory support for respiratory distress syndrome, were reviewed. In 31 infants signs of patent ductus arteriosus developed. In a comparison group of 31 infants, the mean daily fluid volume was 144 ml/kg/24 hours, and the mean body weight was 102% of expected, differing significantly from the 189 nl/kg/24 hours, and 114% of expected weight in those infants who developed PDA. Those infants who developed PDA had not differed significantly from the comparison group in either mean daily fluid volumes or expected weights prior to a period two days before clinical evidence of PDA. Seven infants developed PDA in association with increased fluid administration on more than one occasion during nursery stay. Diuresis after excessive fluid administration was associated with improvement in, or resolution of, signs of PDA in many infants. The results suggest that excessive fluid administration to premature infants with RDS may be one factor associated with the developed of PDA complicating RDS (PDA/RDS).

Body Weight↗
PubMed1976

Long-term results of surgical treatment for pulmonary valve stenosis.

109 children who survived surgical treatment for isolated pulmonary valve stenosis were followed for up to 17 years. In all the postoperative status was assessed as satisfactory. Cardiac catheterization repeated in 43 gave a resting valve gradient below 40 mmHg. The 22 children whose pulmonary valves had been excised were as healthy as the 87 who had undergone pulmonary valvotomy. Consideration was given to the desirable length of postoperative review. Except for the few children with symptoms before operation, a postoperative increase in exercise tolerance was not a feature.

Adolescent↗