PubMed Health⌕ Search

Biomedical subjects

D A Fyfe

Publications and source records attributed to D A Fyfe.

71 records · Page 4Linked to original sources

Fifteen-year experience with surgical repair of truncus arteriosus.

From 1965 until March, 1982, 167 patients underwent surgical repair of truncus arteriosus. The age at operation ranged from 18 days to 33 years (mean 6 years). There were 48 hospital deaths (28.7%). The following factors had a positive correlation with the possibility of a surgical death: age at operation less than 2 years (p less than 0.001), a postrepair pulmonary arterial/left ventricular pressure ratio greater than 0.5 for patients with two pulmonary arteries (p less than 0.001) and greater than 0.6 for patients with unilateral absence of a pulmonary artery (p less than 0.02), and a postrepair right ventricular/left ventricular pressure ratio greater than 0.8 (p less than 0.008). The 119 hospital survivors were followed up for a total of 829 person-years. Late survival rate at 5 years was 84.4% and at 10 years, 68.8%. Preoperative factors that correlated with a reduced long-term survival rate were as follows: increasing age at operation (p = 0.004), the presence of moderate or severe truncal valve insufficiency (p = 0.008), lower pulmonary/systemic flow ratio (p = 0.04), and unilateral absence of a pulmonary artery (p less than 0.001). Thirty-six patients required reoperation during the follow-up period (30%) primarily for replacement of the right ventricular-pulmonary arterial conduit and/or for truncal valve replacement. The long-term results obtained in these patients support the need for early repair of the anomaly, improvement in the methods for control or repair of the truncal valve insufficiency, and the continued search for better extracardiac valved conduits.

Adolescent↗

Clinical and therapeutic aspects of Haemophilus influenzae pericarditis in pediatric patients.

Two cases of Haemophilus influenzae type B pericarditis are presented which demonstrate the major clinical features and sequelae of this serious illness. These cases are analyzed together with 77 others from the literature to characterize the clinical features, natural history, and optimal therapy. H. influenzae pericarditis is an increasingly frequent disease of young children. A mild prodromal illness is often followed by rapid progression of cardiac compromise until death ensues, unless pericarditis is diagnosed and treated appropriately. The development of cardiomegaly in a febrile patient with a Haemophilus infection is an indication for echocardiography, which is diagnostic of the pericardial effusion. Initial cultures of pericardial aspirates will be positive in 75% of cases even when antibiotic therapy has been initiated. Use of appropriate parenterally administered antibiotics, in combination with early surgical pericardial drainage or partial pericardiectomy, should minimize morbidity and mortality and prevent acute constrictive sequelae.

Anti-Bacterial Agents↗

Continuous-wave Doppler determination of the pressure gradient across pulmonary artery bands: hemodynamic correlation in 20 patients.

The feasibility and accuracy of continuous-wave Doppler echocardiography in measuring pressure gradients across the pulmonary artery band were assessed. Simultaneous continuous-wave Doppler and catheter pressure measurements were prospectively performed in 20 patients with complex congenital heart disease and prior pulmonary artery banding. In two other patients, adequate Doppler signals could not be obtained. Doppler velocity was converted to pressure gradient by using the modified Bernoulli equation. Simultaneous continuous-wave Doppler spectral envelopes and catheter pressure wave forms were digitized at 10-ms intervals to obtain maximal instantaneous, mean, and peak-to-peak pressure gradients. The maximal Doppler gradient ranged from 23 to 154 mm Hg, and the simultaneous maximal catheter pressure gradient ranged from 34 to 168 mm Hg. The correlation (r) between these two measurements had a coefficient of 0.98 and a standard error of the estimate (SEE) of 7 mm Hg. The peak-to-peak systolic gradient ranged from 17 to 156 mm Hg and correlated with the maximal Doppler gradient (r = 0.95; SEE = 11 mm Hg). The mean Doppler and mean catheter pressure gradients also were correlated (r = 0.93; SEE = 9 mm Hg). As Doppler echocardiography measures instantaneous velocity and therefore instantaneous pressure gradient, the more precise correlation was between Doppler gradient and maximal instantaneous catheter gradient rather than peak-to-peak systolic gradient. Continuous-wave Doppler echocardiography is an accurate noninvasive technique for measurement of pressure gradients across pulmonary artery bands. In combination with clinical evaluation and two-dimensional echocardiography, it should substantially aid clinical decision making.

Adolescent↗

Extracardiac conduit obstruction: initial experience in the use of Doppler echocardiography for noninvasive estimation of pressure gradient.

Extracardiac valved conduits are often employed in the repair of certain complex congenital heart defects; late obstruction is a well recognized problem that usually requires catheterization for definitive diagnosis. A reliable noninvasive method for detecting conduit stenosis would be clinically useful in identifying the small proportion of patients who develop this problem. Continuous wave Doppler echocardiography has been used successfully to estimate cardiac valvular obstructive lesions noninvasively. Twenty-three patients with prior extracardiac conduit placement for complex congenital heart disease underwent echocardiographic and continuous wave Doppler echocardiographic examinations to determine the presence and severity of conduit stenosis. In 20 of the 23 patients, an adequate conduit flow velocity profile was obtained, and in 10 an abnormally increased conduit flow velocity was present. All but one patient had significant obstruction proven at surgery and in one patient, surgery was planned. In three patients, an adequate conduit flow velocity profile could not be obtained but obstruction was still suspected based on high velocity tricuspid regurgitant Doppler signals. In these three patients, subsequent surgery also proved that conduit stenosis was present. Doppler-predicted gradients and right ventricular pressures showed an overall good correlation (r = 0.90) with measurements at subsequent cardiac catheterization. Continuous wave Doppler echocardiography appears to be a useful noninvasive tool for the detection and semiquantitation of extracardiac conduit stenosis.

Adolescent↗

Transtelephonic monitoring in pediatric patients with clinically suspected arrhythmias.

Evaluation of patients with symptoms suggestive of cardiac arrhythmias is difficult using standard studies if the episodes are infrequent and have a short duration. Transtelephonic electrocardiographic recorders were provided for 41 patients with suspected arrhythmic episodes. None had previously documented arrhythmia. There were 18 males and 23 females (age range 14 months to 19 years; mean 10.9 years). The interval prior to a diagnostic transmission was 0.5 to 8 months (mean 2.5 months). Twenty-one of 41 patients (51%) provided transmissions during a typical episode, nine of which were abnormal. Paroxysmal supraventricular tachycardia was found in eight patients and unsuspected intermittent complete heart block in one patient. The remaining 12 patients had normal sinus rhythm. Twenty patients did not transmit because episodes either were too brief or did not recur. Transtelephonic monitoring was effective in the diagnosis of certain arrhythmias that are infrequent and short in duration. Normal transmitted electrocardiograms during a typical symptomatic episode excluded cardiac arrhythmias.

Adolescent↗

Chest pain in pediatric patients presenting to a cardiac clinic.

Records of 67 pediatric patients with a primary complaint of chest pain were reviewed to determine the frequency of associated cardiac disease. Only four of 67 (6%) had chest pain associated with cardiac diseases that usually cause chest pain. Fifty-seven (85%) patients had chest pain in which no clear cause could be determined. Of these 57, 20 patients also had isolated congenital cardiac anomalies, i.e., atrial septal defect. A causal relationship of these lesions to the chest pain could not be established. Thirty-four of the 37 patients with chest pain and no cardiac abnormalities were evaluated by telephone at a mean of 13 months after their clinic assessment. Twenty-nine of the 34 were either asymptomatic or had reduced symptoms. There was no correlation between duration of symptoms prior to their clinical study and the persistence of chest pain at follow-up. From this study, we conclude that chest pain in pediatric patients is infrequently due to cardiac disease even when associated with previously unsuspected, isolated congenital cardiac lesions. Idiopathic chest pain tends to be self-limited.

Adolescent↗

Distribution of gold among plasma fractions in rheumatoid patients undergoing chrysotherapy compared with its distribution in plasma incubated with aurothiomalate in vitro.

The distribution of gold among the globulin, albumin, and unbound fractions of plasma, obtained either from rheumatoid patients receiving long-term aurothiomalate therapy or from samples incubated with aurothiomalate in vitro, has been investigated. In the rheumatoid patients it has been found that, although the majority of the plasma gold is always bound to albumin, the distribution varies cyclically in phase with the dose schedule. An explanation of these phenomena is provided, based on data obtained from the reaction between aurothiomalate and plasma constituents in vitro.

Arthritis, Rheumatoid↗

Determination of gold in plasma and plasma fractions by atomic absorption spectrometry and by neutron activation analysis.

Three techniques of gold analysis, flame and electrothermal atomic absorption spectrometry and neutron activation analysis, have been compared, using plasma and plasma fractions (derived by gel chromatography) from rheumatoid patients receiving aurothiomalate therapy and from plasma samples incubated with aurothiomalate in vitro. The three methods correlated well in the analysis of gold in whole plasma, but only neutron activation analysis was suitable for the assay of all the plasma fractions. The susceptibility of the two atomic absorption methods to interference by sodium chloride was investigated.

Gold↗

Comparison of intraoperative transesophageal echocardiography to epicardial imaging in children undergoing ventricular septal defect repair.

Intraoperative transesophageal echocardiography was compared with epicardial echocardiography after ventricular septal defect repair. This comparison was made in 18 children aged 7 to 137 months (median, 32 months), weighing 6.3 to 49.1 kg (median, 10.8 kg) from November 1989 to January 1991. Ventricular septal defect types were perimembranous (six), malalignment (seven), supracristal (three), midmuscular (one), and inlet (one). Eight children had isolated ventricular septal defects, four had tetralogy of Fallot, three had double outlet right ventricle, two had double chambered right ventricle, and one had pulmonary stenosis. Patch interrogation was complete in 17 of 18 transesophageal echocardiography and 16 of 18 epicardial echocardiography studies. Inability to fully interrogate the ventricular septal defect patch by epicardial echocardiography occurred in two children as a result of anterior ventricular septal defect location, limited epicardial exposure, and surgical hardware interference. Incomplete transesophageal echocardiography patch interrogation occurred in the child with the midmuscular ventricular septal defect. Seven residual ventricular septal defects were documented by color flow Doppler in six patients. Five of seven residual defects were demonstrated by both real-time transesophageal echocardiography and epicardial echocardiography imaging. Transesophageal echocardiography and epicardial echocardiography missed 1 and 7 defects, respectively. The missed defects were different with each technique and were confirmed by postoperative surface echocardiography. No residual defects of sufficient size to require reoperation were found as determined by combination color flow jet analysis and intraoperative oximetry (no pulmonary to systemic flow ratio was greater than 1.50). Patches caused two-dimensional and Doppler signal masking, but this was not limiting because all residual defects were found at the margins of the ventricular septal defect patch.(ABSTRACT TRUNCATED AT 250 WORDS)

Child, Preschool↗