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Biomedical subjects

E H Botvinick

Publications and source records attributed to E H Botvinick.

125 records · Page 7Linked to original sources
PubMed1977

The application of radionuclide infarct scintigraphy to diagnose perioperative myocardial infarction following revascularization.

To evaluate the application of radionuclide infarct scintigraphy to diagnose myocardial infarction after revascularization, we obtained postoperative technetium 99m pyrophosphate myocardial scintigrams, serial electrocardiograms and CPK-MB isoenzymes in ten control and 51 revascularized patients. All control patients had negative electrocardiograms and scintigrams, but eight had positive isoenzymes. Eight revascularized patients had positive electrocardiograms, images and enzymes and two had positive scintigrams and enzymes with negative electrocardiograms. Thirty-four patients with negative electorcardiograms and scintigrams had positive isoenzymes; in only seven patients were all tests negative. Our data suggest radionuclide infarct scintigraphy is a useful adjunct to the electrocardiogram in diagnosing perioperative infarction. The frequent presence of CPK-MB in postoperative patients without other evidence of infarction suggests that further studies are required to identify all factors responsible for its release.

Adult↗
PubMed1977

Right ventricular compression as a sign of cardiac tamponade: an analysis of echocardiographic ventricular dimensions and their clinical implications.

We have identified pericardial effusion by echocardiography in 174 patients. Seventeen had cardiac tamponade which was not always clinically obvious. Right ventricular narrowing or compression, occurring in the minor axis at end diastole and end expiration, to 7 +/- 2 mm or less, was strongly associated with tamponade in patients with effusion. Right ventricular compression and signs of tamponade abated with pericardiocentesis. One patient was in tamponade without obvious right ventricular narrowing. Nonetheless, he demonstrated serial increases in right ventricular dimensions which paralleled hemodynamic improvement. Diminished left ventricular end-diastolic dimension, "swinging heart," electrical alternans, reciprocal respiratory variations in right and left ventricular end-diastolic dimensions and variation in amplitude of the mitral D-E slope were nonspecific for tamponade. Evaluation of right ventricular dimensions may be clinically useful to diagnose and monitor cardiac tamponade.

Cardiac Tamponade↗
PubMed1977

Acute myocardial infarction: clinical application of technetium 99m stannous pyrophosphate infarct scintigraphy.

Acute myocardial infarction is being recognized as a spectrum of clinical subsets. This appreciation has been brought about to a large degree by the development of several new tools that can be applied clinically to aid in evaluation of patients with acute infarction, and in some cases to provide short and long-term prognostic information. In the realm of noninvasive methods, several tests utilizing radiopharmaceuticals and scintillation cameras have emerged and are rapidly becoming reliable diagnostic parameters in patients with coronary disease and infarction. Technetium 99m (stannous) pyrophosphate (TcPYP) scintigraphy, one of the first of these techniques to find clinical use, has been shown to be an accurate indicator of acute transmural myocardial infarction and provides added sensitivity and specificity to the diagnosis. Increased diagnostic accuracy, the dimension of visible localization and the potential for infarct sizing promise physicians better understanding of a patient's clinical presentation and a more rational approach to management.

Acute Disease↗
PubMed1976

Noninvasive diagnosis of a false left ventricular aneurysm with radioisotope gated cardiac blood pool imaging. Differentiation from true aneurysm.

Unlike the true left ventricular aneurysm, false aneurysms have recently been shown to be subject to late rupture. Rarely diagnosed before surgery or autopsy, the false aneurysm has never been identified by noninvasive techniques. We report the first such noninvasive diagnosis employing radioisotope gated cardiac blood pool imaging. Due to the unique and possibly life-threatening clinical course and potential for surgical cure of false left ventricular aneurysm, early noninvasive diagnosis by imaging techniques may be critical. The methods shown here are generally applicable, becoming widely available and may help in evaluation of false left ventricular aneurysm as a cause of sudden death.

Aged↗
PubMed1975

Myocardial infarction in closed-chest dogs: a simplified method for production.

Due to our need, we sought a simple method to reliably create myocardial infarction in the closed-chest dog. Previous techniques were dangerous, time consuming, unreliable, and costly. Here we described a new coaxial catheter method by which occluded catheter plugs are embolized selectively to branches of the left coronary artery in closed chest dogs anesthetized with sodium pentobarbital (10 mg/lb). Infarcts varying in size from 3 to 27 g, 2-27% of the left ventricle, were reliably created in dogs weighing 26-70 lb. Complications were rare with only a single fatality in the last 15 procedures. The method proved safe, simple, quick, versatile, reproducible, and inexpensive.

Animals↗
PubMed1975

Echocardiographic demonstration of early mitral valve closure in severe aortic insufficiency. Its clinical implications.

Severe aortic insufficiency may accelerate mitral valve closure. We noted this echocardiographic finding in several patients with the acute onset of severe aortic insufficiency. Accordingly, we examined our total echocardiographic series retrospectively for early closure of the mitral valve (ECMV) in the setting of aortic insufficiency and found it in 11 of 53 patients with confirmed aortic insufficiency. During our study ECMV was fortuitously found in two other patients without aortic insufficiency, ECMV occurred in late diastole following the echocardiographic "A" wave, often associated with s suppressed "A" wave (type "B" ECMV). ECMV presence and subtype, along with other clinical parameters, appeared to be useful in the serial evaluation of the patient with severe aortic insufficiency. Additionally, the analysis of ECMV type helped to clarify the mechanism and significance of the Austin Flint murmur. Analysis of 17 patients with and without ECMV, with severe aortic insufficiency judged clinically (NYHA functional class III or IV) and angiographically (3+), indicated that only ECMV patients had acute aortic insufficiency and demonstrated diminished left ventricular size following successful aortic valve replacement. Although due primarily to aortic insufficiency, ECMV could be influenced by rhythm or conducted abnormalities, co-existent cardiac lesions, and pharmacologic interventions. Exclusive of these factors, ECMV was an excellent sign of acute, torrential aortic insufficiency, and a simple noninvasive indicator of the patient requiring immediate aortic valve replacement.

Adolescent↗
PubMed1975

Noninvasive quantitation of myocardial infarction with technetium 99m pyrophosphate.

We sought to quantitate infarct size using radioactive imaging techniques. Infarcts were created in closed chest dogs. Using a scintillation camera interfaced to a computer, infarct images were made in the anterior, left lateral, LAO, and RAO projections, 48 hours after infarction and 75 to 90 min following the intravenous injection of 15 mCi of Technetium 99m pyrophosphate (Tc-PYP). Images were computer enhanced and area was calibrated with a radioactive grid source of known dimensions. Image radioactivity was normalized for decay and dose corrected for body weight. Animals were sacrificed two hours following the injection Tc-PYP. Postmortem images were also computer enhanced and calibrated. Gross infarct area and weight were estimated and transmural biopsies were evaluated for Tc-PYP activity and analyzed for creatine phosphokinase (CPK) content. Contiguous biopsies were pathologically analyzed and graded. There was a negative correlation between tissue Tc-PYP activity and CPK content (r=0.89). Pathologic severity worsened with increased Tc-PYP activity and diminished CPK content. There was a good correlation between gross infarct area and image infarct area, both in vivo (r

Animals↗
PubMedDate not supplied

A consideration of current clinical options for stress imaging in the diagnosis and evaluation of coronary artery disease.

The evolution of technology and our health care system, tinctured by advocacy groups for specific imaging modalities, has produced controversy, relating to the optimal stress imaging method for coronary disease evaluation. Stress perfusion scintigraphy and stress echocardiography advocates seem to make claims that each nullify the other. This extensive, in-depth review of the subject presents facts as well as opinion and experience in an effort to assess the full portrait of the issue for consideration by advocates as well as those many yet undecided. The issue is an evolving one, affected strongly by the reader's own experience. The presentation is not meant to be the final word. Rather, it seeks to present a basis for understanding and progress in both fields.

Coronary Circulation↗
PubMedDate not supplied

Diagnostic utility of tomographic myocardial perfusion imaging with technetium 99m furifosmin (Q12) compared with thallium 201: results of a phase III multicenter trial.

BACKGROUND: Based on physical properties, 99mTc-labeled perfusion agents offer several advantages over 201Tl for myocardial perfusion imaging. The results of in vivo and experimental studies, along with preliminary experience in human subjects, have shown 99mTc-labeled furifosmin to be a promising new perfusion tracer. The purpose of this study was to evaluate the safety of a new myocardial perfusion agent, 99mTc-labeled furifosmin (Q12), and determine the concordance of furifosmin perfusion scintigraphy to 201Tl imaging. In addition, we sought to determine the normalcy rate of myocardial scintigraphy with furifosmin. METHODS AND RESULTS: One hundred fifty patients constituted the study group in this multicenter trial. Patients underwent exercise testing with furifosmin injected at peak exercise, and tomographic imaging was begun 15 to 30 minutes afterward. After a separate injection, resting images were obtained 3 to 4 hours later. Thallium scintigraphy was performed within 2 weeks of the furifosmin scans, after a similar exercise workload. Patients with a low likelihood of coronary artery disease (n = 39) also underwent furifosmin imaging. All images were processed and displayed in uniform manner and interpreted by a panel of readers. No adverse effects or clinically important laboratory alterations were related to furifosmin imaging. Image quality was slightly better with furifosmin than with thallium. The overall concordance between the perfusion studies was 86% (kappa value = 0.669). The normalcy rate for furifosmin scintigraphy was 100%. CONCLUSIONS: 99mTc-labeled furifosmin is a promising new 99mTc-labeled myocardial perfusion agent, providing diagnostic results similar to those obtained with 201Tl.

Coronary Disease↗
PubMedDate not supplied

Fast acquisition of myocardial SPECT images with Tc-99m sestamibi for the diagnosis of coronary artery disease.

BACKGROUND: Shortening the acquisition time for myocardial single-photon emission computed tomographic (SPECT) imaging increases patient comfort and laboratory throughput. The purpose of this study was to compare the diagnostic accuracy for coronary artery disease detection of myocardial SPECT images acquired in 5 to 10 minutes versus 25 minutes using Tc-99m methoxyisobutylisonitrile (Tc-99m sestamibi) and a single-head gamma camera. METHODS AND RESULTS: Forty-one subjects had a standard 1-day rest/stress Tc-99m sestamibi myocardial SPECT study. Two sets of rest and stress images were acquired on the same day for each subject. One set of images was acquired with a 5- to 10-minute fast acquisition protocol; the second set of images was acquired with a 25-minute standard protocol. The accuracies of the fast and standard protocols for identifying individuals with and without coronary artery disease were equivalent. Accuracy was 76% for the fast protocol and 73% for the standard protocol in individuals with at least one coronary stenosis > or = 70%. The accuracies of the two protocols for identifying individual coronary arteries with stenoses > or = 70% also were equivalent. Accuracy was 77% for the fast protocol and 74% for the standard protocol. CONCLUSIONS: SPECT myocardial images may be acquired in as little as 5 to 10 minutes using Tc-99m sestamibi and a 1-day rest/stress protocol. Accuracy is equivalent to that attained in studies with longer imaging times.

Aged↗
PubMedDate not supplied

Potential added value of three-dimensional reconstruction and display of single photon emission computed tomographic gated blood pool images.

BACKGROUND: Single photon emission computed tomographic (SPECT) acquisition provides potential advantages for blood pool imaging. However, the method has been little applied. METHODS: An improved method of three-dimensional (3-D) reconstruction and display of SPECT equilibrium blood pool scintigrams and related phase data was developed. Dynamic slices and volume-rendered dynamic 3-D images were displayed. Images were viewed from each of 34 solid angles referenced to a sphere surrounding the reconstruction field. Each image pixel was "painted" with intensity-coded regional amplitude and color-coded for its phase angle. The method was applied to evaluate the cardiac anatomy, regional contraction, and related conduction sequence at rest in 17 patients. Twelve had normal left ventricular function including 7 patients with minimal septal preexcitation. Five patients had abnormal left ventricular function, including 2 with left bundle branch block. RESULTS: Slices contained all of the functional information, but necessary data integration was time-consuming and evaluation of chamber size and anatomy was difficult. Three-dimensional projection images condensed and integrated the data, presenting new vantage points on anatomy, contraction, and conduction not otherwise available in the clinically limited angulations of planar images. This provided excellent visual separation of cardiac chambers with full and increased visualization of right and left ventricular wall motion in all segments compared with the conventional projections acquired clinically (p < 0.05). Atria and great vessels were well separated with evident size and function. Phase-angle progression paralleled the electrocardiogram, permitting bypass pathway localization and the direct noninvasive localization of posteroseptal pathways. CONCLUSIONS: The 3-D method permits greater access to and utilization of SPECT blood pool image data. It suggests specific advantages for clinical use.

Adult↗
PubMedDate not supplied

Cine-computed tomography of Ebstein anomaly.

A case of Ebstein anomaly is reported, and the diagnostic potential of cine-CT in assessing the magnitude of the anatomic changes and the presence of right to left intracardiac shunting is evaluated.

Cineradiography↗
PubMedDate not supplied

Quantitation of intracardiac shunts by cine-CT.

Quantitation of intracardiac shunts is important in the evaluation of congenital heart disease and ventricular septal defects postmyocardial infarction. Shunt detection and quantitation is currently performed by either oximetry or radionuclide angiography. Oximetry is an invasive technique and radionuclide angiography, although noninvasive, does not have sufficient spatial resolution to provide detailed anatomic information. The present study evaluated a new technique for quantitating right-to-left shunts by analysis of indicator dilution curves acquired noninvasively using cine-CT. This technique was evaluated in a phantom and in postoperative dogs with a surgically created variable shunt. The phantom model demonstrated the accuracy and reproducibility of the curve analysis algorithm, and the canine model permitted the comparison of oximetry with cine-CT for shunt quantitation. Cine-CT accurately estimated right-to-left shunt fraction when compared with oximetry (r = 0.91) and is more sensitive than oximetry in detecting small shunts. The results of this study suggest that contrast enhanced cine-CT provides a precise noninvasive technique for measuring shunt lesions in congenital and acquired heart diseases.

Animals↗
PubMedDate not supplied

Strategies for extraction of quantitative data from volumetric dynamic cardiac positron emission tomography data.

The ability of positron emission tomography (PET) to serve as a useful myocardial perfusion indicator is well established. We describe a methodology for obtaining reliable quantitative kinetic parameters from dynamic cardiac PET data. Reconstructed images of the myocardium are subdivided into three-dimensional volumes of interest which are used to obtain quantitative measures of myocardial perfusion over physiologically meaningful anatomical regions. The quantitation technique rigorously models the uncertainty of estimated parameters while compensating for effects such as patient motion and partial volumes to arrive at model parameters with well-established confidence intervals.

Coronary Angiography↗