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S Einzig

Publications and source records attributed to S Einzig.

89 records · Page 5Linked to original sources
PubMed1979

Echocardiographic screening to assess the severity of congenital aortic valve stenosis in children.

Recent reports suggest that peak left ventricular systolic pressure can be estimated from the echocardiogram. This study compares the accuracy of echocardiographic measurements with clinical estimates of severity of aortic stenosis derived from information of the Joint Natural History Study. Twenty-seven children with isolated aortic valve stensosis were evaluated clinically and with echocardiography and cardiac catheterization. From the echocardiograms, the ratio of systolic left ventricular wall thickness to internal dimension (Ws/Ds) showed a better correlation (r = 0.82) with peak left ventricular systolic pressure than did the diastolic ratio. However, there was significant variation so that a precise estimate of peak left ventricular systolic pressure could not be made from the echocardiogram. Eight of the 27 patients had a normal Ws/Ds ratio (0.55 or less), and their cardiac catheterization data revealed mild aortic stenosis not requiring operation. In contrast, clinical criteria based on the Natural History Study identified only three of the patients with mild aortic stenosis. Prospective studies are needed to confirm the usefulness of echocardiography in noninvasive evaluation of children with aortic valve stenosis.

Adolescent↗
PubMed1979

Tranylcypromine induced hypertension is not mediated by the inhibition of prostacyclin synthesis.

Tranylcypromine (TCP) is a monoamine oxidase inhibitor used extensively in the treatment of patients with reactive depression. Hypertensive crisis can complicate drug therapy, but the mechanism through which TCP causes high blood pressure is unknown. The present study was undertaken because recent investigations have shown that TCP can inhibit production of a potent vasodilator hormone, prostacyclin (PGI2), by blood vessels, possibly explaining the mechanism of pressor effects by the drug. Heart rate, left atrial, pulmonary artery and aortic pressures were monitored in dogs under control conditions and continuously following the IV infusion of TCP at the rate of 1 mg/kg over a period of one minute. Right femoral and the left internal mammary arteries were obtained during the control period and the left femoral and right internal mammary arteries resected between 6 and 30 minutes following drug infusion for PGI2 studies. Concentrations of the drug that caused significant elevation of the mean systemic pressure to 203 +/- 8 mmHg had no inhibitory effect on PGI2 production. Therefore, the influence of TCP on the hemodynamic parameters does not appear to be mediated through the inhibition of vascular PGI2 synthesis.

Animals↗
PubMed1977

Simultaneous regional myocardial blood flows by tritiated water and microspheres.

Regional myocardial blood flow (RMF) was measured simultaneously by use of labeled 8-mum microspheres and the constant-rate infusion of 3H2O in 22 open-chest dogs (Na pentobarbital anesthesia) under markedly different hemodynamic conditions. Following cardiac excision, three adjacent 80-mg tissue samples were taken from the subendocardial, mid-wall, and subepicardial layers of quadrantal left ventricular (LV) segments of the basal and midventricular cardiac slices, and from one segment of the apical slice, totaling 81 samples per LV. RMF was calculated by the microsphere reference-flow technique and by two 3H2O tissue-uptake models. Good agreement between techniques (r=0.9-0.96) was found in comparing flows to the myocardial layers. Using Kety's "single-mixer" model of 3H2O tissue uptake, fairly good agreement was found between techniques in the 80-mg tissue samples; the cofficient of variation from regression was 18.5% which improved markedly to 12.3% when the flow values for each technique were averaged in the three adjacent samples. Analysis of variance showed that flow to the various LV subdivisions (layer, segment, slice) of control animals was heterogeneous.

Animals↗
PubMedDate not supplied

Nebulized nitroglycerin in children with pulmonary hypertension secondary to congenital heart disease.

Pulmonary hypertension continues to be a major cause of morbidity and mortality, despite new treatments. Since inhaled nitric oxide has been reported to be effective in some cases, we investigated using nebulized nitroglycerine to treat pulmonary hypertension in children with congenital heart disease. Four children (ages 6-72 months) with severe pulmonary hypertension secondary to congenital heart disease (all with membranous ventricular septal defect, undergoing cardiac catheterization) were given 3 cc of nebulized normal saline over 10 min as placebo control, followed by nebulized nitroglycerine (20 micrograms/Kg in 3 cc normal saline). Normal saline administration did not elicit any change, but nitroglycerine administration resulted in the following changes (mean +/- SE, paired statistics): systolic pulmonary artery pressure from 68 +/- 8 to 53 +/- 6 at 10 min into treatment (P 0.006), mean pulmonary artery pressure 47 +/- 4 to 38 +/- 4 (P 0.005), heart rate 131 +/- 8 to 127 +/- 7 (P 0.13), systolic blood pressure 85 +/- 8 to 88 +/- 3 (P 0.7), mean blood pressure 59 +/- 6 to 63 +/- 4 (P 0.5). These results indicate that nebulized nitroglycerine may be an effective, easy to administer, inexpensive, and safe alternative for treatment of severe pulmonary hypertension in children with congenital heart disease, especially in areas where other treatments such as extracorporeal membrane oxygenation or inhaled nitric oxide are inaccessible.

Aerosols↗
PubMedDate not supplied

Fetal echocardiography at West Virginia University: a seven-year experience.

The last decade has seen tremendous growth and utilization of fetal echocardiography. In order to assess the indications and yield of fetal echocardiography at West Virginia University, all fetal echocardiograms performed during a seven-year period were reviewed. There were 931 fetal echocardiograms performed on 803 women during this time period and there was a large increase in referral rate as has been seen in other regions. The highest yield of abnormalities was seen in fetuses referred secondary to the finding of an abnormal fetal cardiac exam on routine screening ultrasound (55.6%), or fetal anomalies of other organs (8.2%). These two indications alone were responsible for 77.8% of identified cases of congenital heart disease by fetal echocardiography during this time period. The resultant findings highlight the need for thorough obstetrical screening ultrasound, including the four chamber view of the heart.

Echocardiography↗
PubMedDate not supplied

Estrogen-induced relaxation in bovine coronary arteries in vitro: evidence for a new mechanism.

Numerous studies have shown estrogen to be vasoactive in various circulations. Our objective was to determine the effect of estrogen on isolated bovine coronary arteries and the possible mechanism. Bovine coronary arteries, precontracted with thromboxane mimetic U46619 were given doses (0.01-30 microM) of 17B-estradiol in the presence and absence of endothelium and these inhibitors: 10 microM indomethacin (cyclooxygenase inhibitor), 10 microM methylene blue (inhibits soluble guanylate cyclase), 100 microM nitro-L-arginine (inhibits nitric oxide synthesis), 100 microM isobutylmethylxanthine (phosphodiesterase inhibitor) and 30 microM mifepristone (Ru38486 steroid receptor antagonist). Our results indicated that, estrogen, in the highest concentration used (30 microM), elicited an acute dose-dependent relaxation of bovine coronary arteries from 4%-68% (n = 15). No major difference in relaxation was observed between coronary arteries with or without endothelium, indicating that the mechanism was endothelium-independent. Indomethacin, nitro-L-arginine and methylene blue did not alter this relaxation, suggesting that relaxant prostaglandins, l-arginine products and cGMP are not involved (n = 11-16), isobutylmethylxanthine enhanced relaxation from 20%-40% (n = 15 p < 0.01), suggests a role for cAMP. Furthermore, mifepristone reduced the relaxation by more than 50% (n = 15 p < 0.05) consistent with the role for estrogen receptors. Based on our study, estrogen causes a dose-dependent relaxation of bovine coronary arteries that does not appear to utilize endothelium, prostaglandins, cGMP or arginine products, but may involve cAMP and estrogen receptors. This study may help justify treating myocardial ischemia with estrogen.

Animals↗
PubMedDate not supplied

Recent developments in the measurement of cardiac output and regional blood flow using indocyanine green and microspheres.

Densitometric studies show that the large flow measurement errors and inability to obtain reproducible densitometer calibrations reported with indocyanine green (ICG) in nearly isotonic saline may have arisen from two sources: (a) slowed optical stabilization, and (b) sedimentation of dye aggregates formed in the salt "solutions" of ICG, both of which are avoidable by preparing the dye in water. The assumptions of the widely used regional blood flow measurement technique using radionuclide-labeled microspheres are described. Simultaneous injection of 8mu and 15mu microspheres in turkeys and in dogs demonstrated the existence of at least 8 mu arteriovenous communications (AVCs) in the stomach and intestine, not previously described by this technique, which, in addition to their physiologic functions, may play a role in production of acute gastric mucosal ischemia and erosions. Similar AVCs, producing a lesser degree of "shunting," were also found in the heart. Loss of 8 mu relative to 15 mu microspheres continued with time in the gastrointestinal circulation.

Arteriovenous Anastomosis↗
PubMedDate not supplied

Childhood acute rheumatic fever: a comparison of recent resurgence areas to cases in West Virginia.

A resurgence of acute rheumatic fever (ARF) was noted over the last 10 years in several areas of the United States. West Virginia was no exception with two reports appearing in the literature confirming an increased incidence in the 1980s among children and adults. The Pediatric Cardiology Division of West Virginia University Children's Hospital had 30 cases of ARF referred between 1980 and 1995, and surprisingly 27 of these cases had been diagnosed since 1986. This article describes our chart review of these 30 cases which studied epidemiological aspects, diagnostic criteria and regional differences by chi-square analysis. Other issues we present include "silent" mitral regurgitation and the unreliability of a history of a recent pharyngitis with or without appropriate antibiotic therapy while considering ARF in the differential diagnosis.

Acute Disease↗