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H Feigenbaum

Publications and source records attributed to H Feigenbaum.

At least 19 recordsLinked to original sources
PubMed1992

Exercise echocardiography.

Exercise echocardiography is a versatile, noninvasive diagnostic test that involves the recording and interpretation of 2-dimensional echocardiograms prior to, during, and after exercise. By analyzing and comparing wall motion at each stage, a prediction about the presence or absence of coronary artery disease can be made. The development of a wall motion abnormality is both sensitive and specific for the presence of a significant coronary stenosis. Changes in regional systolic function during exercise enable the clinician to distinguish between infarction and ischemia. Thus, the test yields information on the presence, extent, severity, and location of coronary artery disease. Echocardiography can be adapted to almost any form of stress, although treadmill or bicycle exercise are most commonly employed. An advantage of bicycle stress echocardiography is the opportunity to image during exercise, rather than relying on postexercise recording. This contributes to enhanced sensitivity, although false-positive results may increase due to the difficulties of analyzing wall motion during strenuous exercise. Exercise echocardiography increases the diagnostic accuracy of stress testing in a manner similar to radionuclide perfusion imaging. It is particularly useful in the setting of an ambiguous stress electrocardiography (ECG) or when a false-negative or false-positive result is suspected. It has been successfully applied to patients following revascularization and yields useful prognostic data in a variety of clinical situations. Exercise echocardiography is being increasingly utilized as a safe and accurate test in patients with known or suspected coronary artery disease.

Coronary Disease↗
PubMed1992

Dobutamine stress echocardiography: correlation with coronary lesion severity as determined by quantitative angiography.

This study was performed 1) to determine the ability of dobutamine stress echocardiography to detect stenoses in individual coronary arteries by utilizing a new model of coronary artery distribution; 2) to evaluate its ability to detect coronary artery stenosis with a minimal lumen diameter less than 1 mm; and 3) to correlate the heart rate at which a positive test result occurs with the severity of coronary artery disease. Eighty-five patients were identified who underwent both dobutamine stress echocardiography and quantitative coronary angiography. During incremental infusion of dobutamine, two-dimensional echocardiograms were obtained at rest, during low and peak stress and after stress. Echocardiograms were interpreted with use of a modified 16-segment model with an anteroinferior overlap scheme. The overall sensitivity of the technique for the detection of significant coronary artery disease (diameter stenosis greater than or equal to 50%) was 95%; specificity was 82% and accuracy 92%. The sensitivity for detection of individual coronary artery lesions did not differ significantly (p greater than 0.05) in the three major coronary artery distributions (79% left anterior descending, 70% left circumflex, 77% right coronary artery). Among 35 stenoses with a minimal lumen diameter less than 1 mm, the test result was positive in 30 (86%). Test results were correctly positive for 88%, 82% and 86% of stenoses in the left anterior descending, left circumflex and right coronary artery distributions, respectively. Multivessel disease was present in 11 of 16 patients with normal wall motion at rest who developed a wall motion abnormality at a heart rate less than 125 beats/min. The incidence of multivessel disease was statistically higher in patients with positive findings on a dobutamine stress echocardiogram at a heart rate less than or equal to 125/min. In conclusion, dobutamine stress echocardiography has high sensitivity and specificity for the detection and localization of coronary artery disease. Detection of stenosis in individual coronary arteries is improved in those lesions with a minimal lumen diameter less than 1 mm. Patients with a positive test result at a heart rate less than or equal to 125 beats/min have a high likelihood of multivessel coronary artery disease.

Adult↗
PubMed1992

Distinguishing ischemic cardiomyopathy from nonischemic dilated cardiomyopathy with coronary echocardiography.

Transthoracic echocardiographic examination of the proximal left coronary system was performed in 59 patients who had dilated cardiomyopathy to determine if this technique could distinguish between ischemic and nonischemic dilated cardiomyopathy. With use of annular array transducers (3.5 or 5 MHz) and digital image processing, echocardiographic visualization of the coronary arteries was successful in 55 (93%) of 59 patients. As assessed by coronary angiography, 32 subjects had ischemic cardiomyopathy and 27 had nonischemic cardiomyopathy. Twenty-seven (84%) of the 32 patients who had coronary artery disease and 24 (89%) of the 27 patients with nonischemic cardiomyopathy were correctly identified. The accuracy of coronary echocardiography was 86% in the entire study group and 93% when patients with inadequate studies were excluded. All subjects who had ischemic cardiomyopathy had evidence of disease by coronary echocardiography or segmental wall motion abnormalities. Multivariate analysis permitted correct classification of 93% of all subjects based on the results of the coronary echocardiogram, evaluation of segmental wall motion and a history of prior myocardial infarction. The correct diagnosis was made in 86% when the results of coronary echocardiography were excluded from analysis using all other echocardiographic and clinical variables. Transthoracic coronary echocardiography can be performed with a high degree of success in patients with dilated ventricles and the technique can reliably distinguish between ischemic and nonischemic dilated cardiomyopathy.

Cardiomyopathy, Dilated↗
PubMed1992

Dobutamine stress echocardiography as a predictor of cardiac events associated with aortic surgery.

Two-dimensional echocardiography can detect regional wall motion abnormalities resulting from myocardial ischemia produced by dobutamine infusion. In 60 patients undergoing elective aortic surgery (27 with aneurysms, 33 with occlusive disease), we evaluated the ability of dobutamine stress echocardiography to predict perioperative cardiac events. Echo images were obtained at rest and during incremental dobutamine infusion to a peak dose of 50 micrograms/kg/min, unless another test end point was reached (angina, heart rate greater than or equal to 85% of age-predicted maximum, significant ST segment depression, or new stress-induced wall motion abnormalities). Dobutamine stress echocardiography results were stratified as follows: group I, no wall motion abnormalities; group II, resting wall motion abnormalities unchanged with stress; group III, stress-induced worsening of resting wall motion abnormalities; group IV, new-onset wall motion abnormalities with stress. Twelve cardiac events occurred within the first 30 postoperative days: three cardiac deaths (5%), six nonfatal myocardial infarctions (10%), two patients with unstable angina (3.3%), and one patient with asymptomatic elevation of creatine phosphokinase MB isoenzymes without electrocardiographic changes (1.7%). Eleven events occurred in the 38 patients with an abnormal dobutamine stress echocardiograph (groups II to IV); in contrast, only one of 22 patients with a normal dobutamine stress echocardiograph (group I) had a cardiac event. These event rates (29% vs 4.6%) differed significantly (p less than 0.025). Dobutamine stress echocardiography is a new, safe, rapid, relatively low cost, noninvasive, nonexercise cardiac stress test for risk stratification before major vascular surgery.

Aged↗
PubMed1992

Digital echocardiography in myocardial infarction.

Probably the most under-utilised application of echocardiography is in patients with coronary artery disease (CAD). This under-utilisation is striking since echocardiography can be very valuable in evaluating the natural history and therapy of CAD. One reason why echocardiography is not being utilised to its fullest is because of the reliance on videotape to record and display echocardiograms. This medium is time consuming and inconvenient for clinicians to review studies, it is not ideal for detecting subtle wall motion abnormalities, and videotape is impractical for comparing serial studies. Recording and storing echocardiograms on a digital medium overcomes these difficulties. Digital cine loops of single cardiac cycles provide great versatility. Multiple views or studies can be displayed simultaneously, subtle changes in wall motion are more easily detected and different views, or serial studies, can be readily compared. Such images can be displayed on computers on the ward or in the coronary care unit (CCU) and be available 24 hours a day, seven days a week at the convenience of the clinician. One does not need to find a recording on a two hour videotape, which may be in the ultrasound instrument, and one can view the exam in 30 sec instead of 5 to 10 min. Regional and global left ventricular function is one of the most important manifestations of CAD. With new therapeutic efforts at restoring myocardial function and limiting infarct expansion, assessing LV function is more important than ever. Digital echocardiography is an extremely practical and convenient way for clinicians to obtain this information.

Echocardiography↗
PubMed1992

Echocardiography in the management of mitral valve prolapse.

Echocardiography plays a major role in the management of patients with mitral valve prolapse (MVP). The technique has greatly enhanced our understanding of the pathophysiology, epidemiology and natural history. There are major and minor echocardiographic diagnostic criteria for prolapse. Major criteria involve the mitral leaflets and include late systolic posterior displacement on M-mode, bulging into the left atrium on 2D long-axis (LAX) view, and thickening and redundancy of the leaflets. Minor criteria include holosystolic posterior prolapse on M-mode, bowing of the mitral leaflets into the left atrium (LA) in the apical 2D views, and late systolic mitral regurgitation on the Doppler echogram. Any of the major criteria should be sufficient to make the diagnosis. One or two minor criteria without a major sign would be questionable. The degree of thickening and redundancy and the presence and quantitation of mitral regurgitation influence prognosis. Echocardiography is also helpful in identifying complications such as endocarditis and ruptured chordae. An echocardiogram may not be necessary for the diagnosis, but it is helpful for prognosis and as a baseline for possible future changes. The frequency of follow-up echocardiograms should be determined by clinical findings. When mitral regurgitation is present, then one should follow LA and left ventricular size and function. Transoesophageal echocardiography may be desirable for better definition of vegetations or flail leaflets and is frequently used to monitor surgical repair.

Echocardiography↗
PubMed1992

Exercise echocardiography.

Exercise testing is an indispensable component of clinical cardiology. Latent disease or the full extent of a problem may not be apparent on a resting examination. Some form of stress is frequently necessary, especially in patients with coronary disease, to appreciate whether a patient has stress-induced ischaemia as manifested by exercise-induced chest discomfort, a drop in blood pressure or electrocardiographic changes of ischaemia. Unfortunately as with every test ECG and clinical monitoring have limitations. Patients may have ischaemia without pain, ECG changes may be non-specific, a resting abnormal ECG has limited value, and the location and amount of ischaemic muscle is not directly assessed. Monitoring the echocardiogram adds significant additional information to routine stress testing. By visualising the myocardium in the exercising individual, it is possible to assess a fundamental manifestation of ischaemia, regional wall motion abnormalities. This information helps identify the vessels and the amount of muscle involved. In addition resting wall motion abnormalities may detect clinically silent infarction or hibernating myocardium. Direct visualisation of the exercising heart provides an improved understanding of a patient's cardiac status. The technique is particularly useful in evaluating revascularisation procedures. Advances in instrumentation have reduced or eliminated many of the technical difficulties with obtaining and interpreting exercise echocardiograms. This examination has become an extremely useful adjunct to routine stress testing.

Coronary Disease↗
PubMed1991

Segmental wall motion abnormalities in the absence of clinically documented myocardial infarction: clinical significance and evidence of hibernating myocardium.

To determine the frequency and significance of left ventricular wall motion abnormalities in patients without clinical evidence of myocardial infarction, we reviewed the two-dimensional echocardiograms of 252 patients who had no history or electrocardiographic evidence of myocardial infarction and who subsequently underwent coronary angiography. Seventy-seven patients (31%) had one or more segmental wall motion abnormalities. Sixty-six of the 77 patients (86%) had significant coronary artery disease (greater than or equal to 50% luminal diameter stenosis). Seventy-four percent of the patients with coronary artery disease had multivessel disease. The left ventricle was divided into anterior and posterior regions. In the 66 patients, there were 77 separate regions with wall motion abnormalities (49 hypokinesis, 22 akinesis, 6 dyskinesis), including 60 regions (78%) supplied by coronary vessels with greater than or equal to 70% stenosis. Thirty-two patients underwent coronary artery bypass surgery or percutaneous transluminal coronary angioplasty. Follow-up echocardiograms were obtained in 19 patients who had wall motion abnormalities involving 22 regions. Twenty of the 22 regions were revascularized. Wall motion improved in 17 of 20 regions (85%) and returned to normal in 15 regions (75%). We conclude that segmental wall motion abnormalities may be detected by echocardiography in up to one third of patients evaluated for suspected coronary artery disease without documented myocardial infarction. These abnormalities are associated with a high likelihood of multivessel disease as well as with significant narrowing of the artery supplying the region demonstrating abnormal wall motion. Improvement in segmental wall motion abnormalities after revascularization suggests that these areas represent regions of hibernating myocardium.

Adult↗
PubMed1991

Echocardiographic detection of coronary artery disease during dobutamine infusion.

BACKGROUND: Two-dimensional echocardiography performed during dobutamine infusion has been proposed as a potentially useful method for detecting coronary artery disease. However, the safety and diagnostic value of dobutamine stress echocardiography has not been established. METHODS AND RESULTS: In this study, echocardiograms were recorded during step-wise infusion of dobutamine to a maximum dose of 30 micrograms/kg/min in 103 patients who also underwent quantitative coronary angiography. The echocardiograms were digitally stored and displayed in a format that allowed simultaneous analysis of rest and stress images. Development of a new abnormality in regional function was used as an early end point for the dobutamine infusion. No patient had a symptomatic arrhythmia or complications from stress-induced ischemia. Significant coronary artery disease (greater than or equal to 50% diameter stenosis) was present in 35 of 55 patients who had normal echocardiograms at rest. The sensitivity and specificity of dobutamine-induced wall motion abnormalities for coronary artery disease was 89% (31 of 35) and 85% (17 of 20), respectively. The sensitivity was 81% (17 of 21) in those with one-vessel disease and 100% (14 of 14) in those with multivessel or left main disease. Forty-one of 48 patients with abnormal echocardiograms at baseline had localized rest wall motion abnormalities. Fifteen had coronary artery disease confined to regions that had abnormal rest wall motion, and 26 had disease remote from these regions. Thirteen of 15 patients (87%) without remote disease did not develop remote stress-induced abnormalities, and 21 of 26 (81%) who had remote disease developed corresponding abnormalities. CONCLUSIONS: Echocardiography combined with dobutamine infusion is a safe and accurate method for detecting coronary artery disease and for predicting the extent of disease in those who have localized rest wall motion abnormalities.

Adrenergic beta-Antagonists↗
PubMed1991

Stress echocardiography: an overview.

Stress echocardiography has come a long way in the past ten to twelve years since it first began. There have been many procedural and technical advances. The results being obtained by those laboratories with active programs are very gratifying. Stress echocardiography is proving to be particularly valuable in women and in evaluating coronary angioplasty. Although the comparison between stress echocardiography and stress nuclear cardiology is actively being debated, the available data would suggest that the results are grossly comparable. There are certain subsets of patients which may be identified where one technique might excel over the other. The most important factor is undoubtedly the competence of the laboratory performing the test. A high quality nuclear study is clearly going to be better than a poor quality echocardiogram and vice versa. However, assuming a high degree of competence in either technique, stress echocardiography has many obvious practical advantages. There is no reperfusion necessary so that the patient does not have to return in four hours. There is no radiation involved. And the results are available immediately after the examination. For all of these reasons it is not surprising that stress echocardiography is gaining in popularity and should play an increasingly important role in the management of patients with coronary artery disease.

Coronary Disease↗
PubMed1990

Role of echocardiography in acute myocardial infarction.

Interventional therapies such as thrombolytic agents, angioplasty and surgery have emerged as important options in the management of patients with myocardial infarction. These therapies are aimed at improving myocardial perfusion with the ultimate improvement or restoration of myocardial function. Two-dimensional echocardiography with digital storage and display is an ideal technique for temporally monitoring regional ventricular function and the effectiveness of interventional therapy. By design, 2-dimensional echocardiography is noninvasive and can be performed conveniently at the bedside. For these reasons, echocardiography is the principal imaging technique at Indiana University Hospital for patients with acute myocardial infarction. Computer retrieval of echocardiograms can be achieved in about 10 seconds at the nurses' station in the coronary care unit. With the availability of such an examination, the physician has a better understanding of the site, size and function of the infarct area. The state of the noninfarcted myocardium is also assessed and may be critical to the patient's prognosis. With the digital recordings, serial studies can be displayed side-by-side, making it easier for the physician to follow the natural history or to judge the effect of therapy. Echocardiography also is useful in identifying many complications that can occur with myocardial infarction. For these reasons, and because echocardiography will also show related cardiac problems, it is indispensable in the management of acute myocardial infarction.

Echocardiography↗
PubMed1990

Comparison of contrast angiography and two-dimensional echocardiography for the evaluation of left ventricular regional wall motion abnormalities after acute myocardial infarction.

Regional left ventricular wall motion abnormalities were assessed using 2-dimensional echocardiography and contrast ventriculography within 12 hours of the onset of chest pain in 20 patients with acute myocardial infarction (AMI); 10 patients had anterior infarctions and 10 had inferior. End-diastolic and end-systolic sinus beats from right anterior oblique contrast ventriculograms were analyzed using the center-line chord technique with both a standard overlap method of chord assignment and a nonoverlap method. Echocardiograms were obtained in parasternal long- and short-axis and apical 2- and 4-chamber views and analyzed using a 16-segment scoring system to derive anterior and infero-posterolateral wall motion indexes using both overlap (10 segments for anterior, 8 inferior) as well as nonoverlap (9 segments anterior, 7 inferior) methods of segment assignment. There was a significant inverse correlation between the standard (nonoverlap) echocardiographic analysis and the standard (overlap) angiographic analysis for infarct regions (y = -0.43 X +1.11, r = -0.59, p less than 0.05). Fifteen of 18 patients with angiographic infarct regional score less than or equal to -1 standard deviation/chord had an echocardiographic index greater than or equal to 1.5, while 15 of 16 patients with echocardiographic regional infarct index greater than or equal to 1.5 had an angiographic score less than or equal to -1 standard deviation/chord. Correlation between the 2 methods for noninfarct territories was poor (r = -0.34) because the angiographic method assesses hyperkinesis while the echocardiographic method does not.(ABSTRACT TRUNCATED AT 250 WORDS)

Contrast Media↗
PubMed1990

Improvement in rest and exercise-induced wall motion abnormalities after coronary angioplasty: an exercise echocardiographic study.

Exercise echocardiography was performed in 36 patients to evaluate functional improvement after coronary angioplasty. Thirty-one patients (86%) had provokable ischemia before angioplasty including 22 with an abnormal exercise electrocardiographic test (angina or ST depression), 25 with an abnormal exercise echocardiogram (exercise-induced wall motion abnormalities) and 16 with both tests abnormal. Nineteen patients had no induced ischemia after angioplasty. Seventeen (47%) continued to have ischemia that was limited in 12 to exercise-induced wall motion abnormalities, which were less severe compared with those of preangioplasty studies. Fifteen (65%) of 23 patients had improvement in rest wall motion abnormalities after angioplasty. The rest to immediate postexercise change in global wall motion score was significantly improved after angioplasty. The change in regional wall motion score was significantly improved after angioplasty in patients with single vessel right or left circumflex coronary artery disease and approached significant improvement (p = 0.06) in those with single vessel disease of the left anterior descending coronary artery. Exercise echocardiography improves the sensitivity of functional testing for ischemia, aids in localizing the ischemic zone and documents improvement in regional function after coronary angioplasty.

Angioplasty, Balloon, Coronary↗
PubMed1990

Prognostic value of a normal exercise echocardiogram.

Follow-up information was obtained from 148 patients who had normal resting and post-treadmill exercise echocardiograms to determine the prognostic value of a normal exercise echocardiogram in patients evaluated for suspected coronary artery disease. There were 77 men and 71 women with a mean age of 52.5 years and a pretest likelihood of coronary artery disease of 39%. Patients were followed for a mean duration of 28.4 +/- 8.5 months. The exercise ECG was abnormal in 69 patients (47%) including 28 who had ischemic responses. Cardiac events occurred in six patients, three with normal and three with abnormal exercise ECGs. Events occurred only in those patients (6 of 68) who exercised to work loads less than 6 METs or who achieved less than 85% of the age-predicted maximal heart rate. Three patients had coronary artery bypass grafting for angina from 10.5 to 22.5 months after echocardiography. A fourth patient had bypass grafting for mild single-vessel disease at the time of mitral valve replacement. Two patients had myocardial infarctions (0.85% per year) at 7.5 and 41 months after echocardiography. There were no deaths. Coronary revascularization is infrequently required in the 28 months after a normal exercise echocardiogram. A normal exercise echocardiogram in a patient with good exercise capacity was predictive of an excellent prognosis, even in those who had abnormal exercise ECGs. Myocardial infarction and death were rare events, even in patients with decreased exercise capacity.

Adult↗
PubMed1990

Balloon valvuloplasty.

Percutaneous balloon valvuloplasty has been used for several years for the treatment of stenosis of all four cardiac valves. It has been particularly effective in pulmonary stenosis in children and in rheumatic mitral stenosis, especially in the younger age groups without severe calcification. After initial enthusiasm, results have not been as good in severe calcific aortic stenosis, although there is a place for aortic valvuloplasty in patients who are truly inoperable for reasons of age or coexisting disease. The procedure also may be applicable to occasional cases of tricuspid stenosis. The techniques used and results obtained with these procedures at Indiana University are described.

Adolescent↗
PubMed1979

Serial echocardiographic appearance of healing bacterial vegetations.

Serial M mode and cross-sectional echocardiograms were obtained from six patients who had been treated with antibiotic drugs for infectious endocarditis. Three to six M mode echocardiograms and one to six cross-sectional echocardiograms were obtained from each patient over a follow-up period averaging 50 weeks (range 10 to 108 weeks). On echocardiography, vegetations were observed to have become smaller and more echo-reflective with healing. A dramatic change was seen in two patients after peripheral embolization. M mode echocardiography was particularly helpful in determining the quality of echo reflection by vegetations; cross-sectional echocardiography was more helpful in judging the size and shape of a vegetation. Echocardiography is ideally suited for the serial visualization of healing vegetations in patients who do not require early valve replacement. It may prove helpful to examine serially valve vegetations with both M mode and cross-sectional echocardiography when following up patients with infectious endocarditis treated with antibiotic agents.

Adult↗