PubMed Health⌕ Search

Biomedical subjects

R S Meltzer

Publications and source records attributed to R S Meltzer.

At least 91 records · Page 5Linked to original sources
PubMed1981

Cardiac catheterization under echocardiographic control in a pregnant woman.

A 22 year old woman had signs of rheumatic mitral and aortic valve disease early in pregnancy. Cardiac catheterization was performed during her third month of pregnancy under two-dimensional echocardiographic control without the use of ionizing radiation. Severe mitral stenosis with mild aortic stenosis was found. Five cubic centimeters of 5 percent dextrose in water were injected by hand to obtain left ventriculograms and supravalvular aortograms of sufficient quality to diagnose valvular regurgitation. The use of "echo-catheterization" may have significant advantages in selected clinical situations.

Adult↗
PubMed1981

Echocardiographic aspects of cardiac amyloidosis.

We report the M-mode and two-dimensional echocardiographic findings in a patient with familial amyloidosis. The diagnosis was made by the clinical picture and histologic evidence of amyloid in peripheral nerve biopsy. Though the patient had no clinical sign of heart failure, extensive involvement of the heart was demonstrated by echocardiography. M-mode echocardiography revealed increased right ventricular wall thickness in conjunction with symmetric increase in left ventricular wall thickness. On two-dimensional echocardiography, the entire interventricular septum and the papillary muscles were more dense than normal. These high density echoes had a "granular and sparkling" pattern. This case shows that cardiac amyloidosis can be diagnosed in the pre-clinical, asymptomatic state by M-mode and two-dimensional echocardiography. When symptomatic, confusion with constrictive pericarditis may be avoided non-invasively.

Adult↗
PubMed1980

The source of ultrasound contrast effect.

Evidence that microbubbles are the main sources of ultrasound contrast in injected solutions has been largely indirect. To investigate this directly, we examined freshly agitated indocyanine green, freshly agitated water, commercially prepared precision microbubbles (diameter 75 +/- 25 mu) in gelatin, carbonated water, "degassed" indocyanine green solution, and "degassed" water in one or more of four different assay systems. Only fluids with microbubbles produced ultrasound contrast. Injected contrast material rose in a water bath at a rate that identified it as being caused by microbubbles. Indocyanine green and gelatin surface tensions were measured and found to be low (43 dynes/cm2), thus explaining their tendency to stabilize the microbubbles that cause ultrasound contrast effect when injected and to hold foam after agitation. The force of hand injections (force similar to that used clinically through catheters and 19-gauge or 23-gauge needles) was below the force needed to cause cavitation or ultrasound contrast effect. Microbubble content could be quantified by the decrease in amplitude of the echo from a structure distant to the microbubbles. We conclude that that the ultrasound contrast effect seen in peripherally injected fluids is caused by microbubbles present in the injectant. The contrast is not due to cavitation at needle tips, and it can be quantified over a limited range. Improved design for a peripheral contrast agent is suggest.

Animals↗
PubMed1980

Pulmonary wedge injections yielding left-sided echocardiographic contrast.

Ultrasound contrast on the left side of the heart without the need for left heart catheterisation was achieved by hand injections of 8 to 10 ml 5 per cent dextrose solution through a catheter in the pulmonary wedge position. Injections were performed in 18 patients undergoing routine cardiac catheterisation and M-mode or two-dimensional echocardiography was used. An adequate wedge position was attained in 17 of the 18 patients. Nine had injections through Cournand catheters, three through Swan-Ganz catheters, and five through both. In 11 of these 17 patients left atrial or left ventricular echocardiographic contrast was seen immediately after wedge injection. Two patients showed diminished or absent contrast on later injections from the same position. Better results were obtained with the Cournand catheter (11/15 positive) than with the Swan-Ganz (1/8 positive) catheter. Pulmonary artery injections proximal to the wedge position did not cause left-sided contrast. No complications were observed. The safety of this method remains to be determined.

Adult↗
PubMed1980

Mitral annular calcification: clinical and echocardiographic features.

One hundred records from patients with the single or two-dimensional echocardiographic (2DE) diagnosis of mitral annular calcification (MAC) were analyzed. 2DE manifestations of MAC included a characteristic bright structure located at the junction of the A-V groove and posterior mitral leaflet. Sixteen of the 100 patients had idiopathic hypertrophic subaortic stenosis (IHSS), a 44% (16/36) incidence in all patients with IHSS having echoes during the study period. IHSS patients with MAC were significantly older (mean 61 years vs. 43 years, p < .005) than 20 other IHSS patients without MAC studied during the same period. Both IHSS patients and non-IHSS patients with MAC had significantly lower serum calcium levels than normals or the IHSS patients without MAC. These observations support the view that the pathogenesis of MAC is related to degenerative changes from aging and increased stress on the mitral apparatus. Alterations in calcium metabolism possibly contribute to calcium deposition in the mitral annulus.

Calcinosis↗
PubMed1980

Non-invasive quantification of experimental canine myocardial infarct size using two-dimensional echocardiography.

In order to study whether wall motion abnormalities detected by two-dimensional (2D) echocardiography can be quantified and correlated with infarct size, we compared wall motion abnormalities viewed by 2D echocardiography in experimental canine infarction with post-mortem infarct size. Nineteen mongrel dogs underwent left anterior descending coronary artery snare occlusion. They were sacrificed 6 h later. Infarct sizing was done by technetium 99-m stannous pyrophosphate scintigraphy of the excised, sliced left ventricles. Fourteen dogs had both 2D echo wall motion abnormalities and infarctions. Four dogs failed to develop infarction and had no or minimal wall motion abnormalities. Inter-observer variation in 2D echocardiographic measurements was small. Wall motion abnormalities correlated with infarct size both in the 14-dog subgroup with infarction (r = 0.75, P less than 0.003) and all the 18 dogs that completed the protocol (r = 0.87, P less than 0.001). Thus, wall motion abnormalities in experimental canine myocardial infraction can be roughly quantified by 2D echocardiography and correlated with post-mortem infarct size measured by scintigraphy.

Animals↗
PubMed1979

Two dimensional echocardiographic quantification of infarct size alteration by pharmacologic agents.

In 27 closed chest dogs left ventricular wall motion abnormalities assessed quantitatively with two dimensional echocardiography were used as a measure of myocardial infarct size, and the change in extent of segmental wall motion abnormalities due to drug intervention early after infarction was evaluated. The extent of wall motion abnormalities was measured with echocardiography before and at 20 and 40 minutes and 5 1/2 hours after coronary occlusion. Three subgroups of dogs received, respectively, an infusion of nitroglycerin, phenylephrine or saline solution. Infarct size was measured with technetium pyrophosphate scintigraphy of the excised left ventricle. The infarct size correlated well with the extent of wall motion abnormalities before death. Wall motion was initially similar among the three groups but was significantly improved after treatment with nitroglycerin (P less than 0.025), remained stable with continued saline infusion and worsened significantly (P less than 0.05) after treatment with phenylephrine. Two dimensional echocardiography can be used to quantify experimental canine myocardial infarction and assess the effect of nitroglycerin.

Animals↗