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Markus Schwaiger - One of the best experts on this subject based on the ideXlab platform.
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regional diastolic function by pulsed doppler myocardial mapping for the detection of left ventricular ischemia during Pharmacologic Stress Testing a comparison with Stress echocardiography and perfusion scintigraphy
Journal of the American College of Cardiology, 2000Co-Authors: Helene Von Bibra, Anja Tuchnitz, Annegret Klein, Jan Schneidereicke, Albert Schomig, Markus SchwaigerAbstract:Objectives We evaluated regional diastolic function by pulsed Doppler myocardial mapping for the detection of left ventricular ischemia during Pharmacologic Stress Testing. Background Evaluation and quantification of diastolic myocardial function remain a challenge for imaging techniques in Stress tests. METHODS A prospective study compared the detection of coronary artery stenosis: 1) by pulsed Doppler myocardial mapping, 2) by two-dimensional echocardiographic dobutamine Stress test, and 3) by perfusion scintigraphy in 64 patients using coronary angiography for reference. An age matched subgroup of 10 patients with normal angiograms and two-dimensional echocardiographic Stress test served as control group. Peak myocardial contraction velocity (Vc) and lengthening rate during early diastolic left ventricular (LV) filling (Ve) were measured in 12 LV segments from three apical views. RESULTS In controls, myocardial velocities increased during Stress by ≥3.6 cm/s (p < 0.001). In LV segments depending on a stenosed artery (n = 70), Ve decreased by ≥1 cm/s and, thus, was different from control segments (n = 112, p < 0.001) and from scar segments (n = 13, p < 0.01), whereas the change of Vc was similar to that in scar segments. A Stress induced 2 cm/s reduction of Ve discerned the best diagnostic accuracy (sensitivity 84%, specificity 93%) in comparison with two-dimensional echocardiography (78% and 71%) and perfusion scintigraphy (61% and 86%). Using receiver operating curves at incremental levels of luminal narrowing, these relations persisted. CONCLUSIONS Quantification of diastolic myocardial function by pulsed Doppler myocardial mapping during dobutamine Stress test was shown to be a feasible, accurate, reproducible, noninvasive technique that should be considered to be a sensitive alternative to the present echocardiographic and scintigraphic imaging techniques for Stress tests.
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regional diastolic function by pulsed doppler myocardial mapping for the detection of left ventricular ischemia during Pharmacologic Stress Testing a comparison with Stress echocardiography and perfusion scintigraphy
Journal of the American College of Cardiology, 2000Co-Authors: Helene Von Bibra, Anja Tuchnitz, Annegret Klein, Jan Schneidereicke, Albert Schomig, Markus SchwaigerAbstract:AbstractObjectivesWe evaluated regional diastolic function by pulsed Doppler myocardial mapping for the detection of left ventricular ischemia during Pharmacologic Stress Testing.BackgroundEvaluati...
Mario S Verani - One of the best experts on this subject based on the ideXlab platform.
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myocardial perfusion imaging during Pharmacologic Stress Testing
Cardiology Clinics, 1994Co-Authors: John J Mahmarian, Mario S VeraniAbstract:Pharmacologic Stress Testing has gained wide acceptance as an alternative to exercise Stress Testing when combined with myocardial perfusion scintigraphy and has expanded the applicability of cardiac imaging to the large number of patients who wither cannot exercise or are limited to a submaximal effort. The Pharmacologic Stressors presently available are either coronary vasodilators (e.g., adenosine, dipyridamole) or beta-agonists (e.g., dobutamine). This article summarizes the physiologic principles underlying Pharmacologic Stress imaging and its clinical utility in evaluating patients with suspected coronary artery disease.
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exercise and Pharmacologic Stress Testing for prognosis after acute myocardial infarction
The Journal of Nuclear Medicine, 1994Co-Authors: Mario S VeraniAbstract:To evaluate patients after acute myocardial infarction (MI), myocardial perfusion imaging provides prognostic parameters that help identify patients at risk for subsequent cardiac events. In addition, myocardial perfusion imaging can be used to identify functionally important residual stenoses and multivessel disease, even in patients who have received thrombolytic therapy. Three parameters of myocardial perfusion imaging emerge as strong predictors of future cardiac events in post-MI patients: (1) presence of transient defects, (2) the number of transient defects and (3) increased radiotracer uptake in the lung. In addition, radionuclide left ventricular ejection fraction (LVEF) is one of the most powerful predictors of subsequent risk for cardiac events, particularly cardiac death and congestive heart failure. Cardiac catheterization, for the most part, does not add to the prognostic value of radionuclide Stress Testing. Results of myocardial perfusion imaging studies that employ Pharmacologic Stress instead of submaximal exercise provide strong predictors of prognosis in post-MI patients.
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Pharmacologic Stress Testing mechanism of action hemodynamic responses and results in detection of coronary artery disease
Journal of Nuclear Cardiology, 1994Co-Authors: Abdulmassih S Iskandrian, Mario S Verani, Jaekyeong HeoAbstract:Pharmacologic Stress Testing may be used in the diagnosis of coronary artery disease and risk assessment. The Stress agents may be divided into those that produce primary coronary vasodilation (dipyridamole, adenosine, or adenosine triphosphate) and those that produce secondary vasodilation as a result of increase in myocardial oxygen demand (dobutamine and arbutamine). Assessment of myocardial perfusion and function can be made by single-photon imaging, positron emission tomography, two-dimensional echocardiography, magnetic resonance imaging, and contrast angiography. For assessment of myocardial perfusion, either thallium 201-labeled or technetium-labeled perfusion imaging agents may be used. This article will focus on the mechanisms of action, hemodynamic responses, and results of Pharmacologic imaging in detecting coronary artery disease. The use of Pharmacologic Stress Testing in risk assessment will be discussed in a separate article.
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dobutamine thallium 201 tomography for evaluating patients with suspected coronary artery disease unable to undergo exercise or vasodilator Pharmacologic Stress Testing
Journal of the American College of Cardiology, 1993Co-Authors: John T Hays, John J Mahmarian, Angela J Cochran, Mario S VeraniAbstract:Abstract Objectives. The aim of this study was to assess the feasibility, safety and diagnostic accuracy of a high dose dobutamine infusion in conjunction with thallium-201 single-photon emission computed tomography in 144 patients (72 men and 72 women with a mean age of 65 ± 10 years) unable to perform exercise or Pharmacologic vasodilator Stress Testing. Background. Dobutamine increases myocardial oxygen consumption by increasing heart rate, contractility and arterial blood pressure. In addition, it causes myocardial blood flow heterogeneity and thus may be a useful Stress for noninvasive detection of coronary artery disease. Methods. Dobutamine was administered intravenously at incremental doses of 5, 10, 20, 30 and up to 40 μg/kg per min at 3-min intervals. After 1 min of the maximal dose, 3 mCi of thallium-201 was injected and the infusion was continued for an additional 2 min. Thallium-201 tomography was performed 5 to 10 min after termination of the infusion and 4 h later. The images were visually assessed for the presence and vascular location of perfusion defects and the extent of thallium redistribution. Coronary angiography was performed in 84 patients, with a >50% stenosis considered significant. Results. Dobutamine significantly (p = 0.0001) increased the heart rate (from 75 ± 14 beats/min to 120 ± 23 beats/min), systolic blood pressure (from 136 ± 23 mm Hg to 148 ± 35 mm Hg) and the rate-pressure product (from 10,144 ± 2,517 to 17,858 ± 4,349) from baseline to peak infusion rate, respectively. Most patients (75%) experienced side effects during the infusion, but 74% tolerated a dobutamine dose of 40 μg/kg per min and 97% a dose of 30 μg/kg per min. The more common side effects were typical (26%) and atypical (5%) chest pain, palpitation (29%), flushing (14%), headache (14%) and dyspnea (14%). The overall sensitivity of dobutamine tomography was 86% in the patients who underwent coronary angiography and 84% in those with single-vessel, 82% in those with double-vessel and 100% in those with triple-vessel disease. Seventy-eight percent of vessels with severe (≥70%) stenoses were identified with dobutamine tomography. The specificity of dobutamine tomography was 90% for patients and 86% for individual vessels. Conclusions. A high dose dobutamine infusion in conjunction with thallium tomography appears to be a well tolerated and accurate method for diagnosing coronary artery disease in patients unable to perform exercise or vasodilator Pharmacologic Stress Testing.
Helene Von Bibra - One of the best experts on this subject based on the ideXlab platform.
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regional diastolic function by pulsed doppler myocardial mapping for the detection of left ventricular ischemia during Pharmacologic Stress Testing a comparison with Stress echocardiography and perfusion scintigraphy
Journal of the American College of Cardiology, 2000Co-Authors: Helene Von Bibra, Anja Tuchnitz, Annegret Klein, Jan Schneidereicke, Albert Schomig, Markus SchwaigerAbstract:Objectives We evaluated regional diastolic function by pulsed Doppler myocardial mapping for the detection of left ventricular ischemia during Pharmacologic Stress Testing. Background Evaluation and quantification of diastolic myocardial function remain a challenge for imaging techniques in Stress tests. METHODS A prospective study compared the detection of coronary artery stenosis: 1) by pulsed Doppler myocardial mapping, 2) by two-dimensional echocardiographic dobutamine Stress test, and 3) by perfusion scintigraphy in 64 patients using coronary angiography for reference. An age matched subgroup of 10 patients with normal angiograms and two-dimensional echocardiographic Stress test served as control group. Peak myocardial contraction velocity (Vc) and lengthening rate during early diastolic left ventricular (LV) filling (Ve) were measured in 12 LV segments from three apical views. RESULTS In controls, myocardial velocities increased during Stress by ≥3.6 cm/s (p < 0.001). In LV segments depending on a stenosed artery (n = 70), Ve decreased by ≥1 cm/s and, thus, was different from control segments (n = 112, p < 0.001) and from scar segments (n = 13, p < 0.01), whereas the change of Vc was similar to that in scar segments. A Stress induced 2 cm/s reduction of Ve discerned the best diagnostic accuracy (sensitivity 84%, specificity 93%) in comparison with two-dimensional echocardiography (78% and 71%) and perfusion scintigraphy (61% and 86%). Using receiver operating curves at incremental levels of luminal narrowing, these relations persisted. CONCLUSIONS Quantification of diastolic myocardial function by pulsed Doppler myocardial mapping during dobutamine Stress test was shown to be a feasible, accurate, reproducible, noninvasive technique that should be considered to be a sensitive alternative to the present echocardiographic and scintigraphic imaging techniques for Stress tests.
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regional diastolic function by pulsed doppler myocardial mapping for the detection of left ventricular ischemia during Pharmacologic Stress Testing a comparison with Stress echocardiography and perfusion scintigraphy
Journal of the American College of Cardiology, 2000Co-Authors: Helene Von Bibra, Anja Tuchnitz, Annegret Klein, Jan Schneidereicke, Albert Schomig, Markus SchwaigerAbstract:AbstractObjectivesWe evaluated regional diastolic function by pulsed Doppler myocardial mapping for the detection of left ventricular ischemia during Pharmacologic Stress Testing.BackgroundEvaluati...
Grigorios Korosoglou - One of the best experts on this subject based on the ideXlab platform.
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real time myocardial perfusion imaging for Pharmacologic Stress Testing added value to single photon emission computed tomography
American Heart Journal, 2006Co-Authors: Grigorios Korosoglou, Alaineric Dubart, Gaspar K C Dasilva, Nino Labadze, Stefan E Hardt, Alexander Hansen, Raffi Bekeredjian, Christian Zugck, Joerg Zehelein, Hugo A KatusAbstract:Background Little is known about the incremental value of real-time myocardial contrast echocardiography (MCE) as an adjunct to Pharmacologic Stress Testing. This study was performed to evaluate the diagnostic value of MCE to detect abnormal myocardial perfusion by technetium Tc 99m sestamibi–single photon emission computed tomography (SPECT) and anatomically significant coronary artery disease (CAD) by angiography. Methods Myocardial contrast echocardiography was performed at rest and during vasodilator Stress in consecutive patients (N = 120) undergoing SPECT imaging for known or suspected CAD. Myocardial opacification, wall motion, and tracer uptake were visually analyzed in 12 myocardial segments by 2 pairs of blinded observers. Concordance between the 2 methods was assessed using the κ statistic. Results Of 1356 segments, 1025 (76%) were interpretable by MCE, wall motion, and SPECT. Sensitivity of wall motion was 75%, specificity 83%, and accuracy 81% for detecting abnormal myocardial perfusion by SPECT (κ = 0.53). Myocardial contrast echocardiography and wall motion together yielded significantly higher sensitivity (85% vs 74%, P P P Conclusion Assessment of myocardial perfusion adds value to conventional Stress echocardiography by increasing its sensitivity for the detection of functionally abnormal myocardial perfusion. Myocardial contrast echocardiography and wall motion together provide higher sensitivity and accuracy for detection of CAD compared with SPECT.
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real time myocardial contrast echocardiography for Pharmacologic Stress Testing is quantitative estimation of myocardial blood flow reserve necessary
Journal of The American Society of Echocardiography, 2004Co-Authors: Grigorios Korosoglou, Alaineric Dubart, Nino Labadze, Alexander Hansen, Joerg Zehelein, Gaspar K C Da Silva, Mark Rosenberg, Helmut F KuechererAbstract:Abstract Background Little is known about the diagnostic accuracy of quantitative real-time myocardial contrast echocardiography (MCE) as an adjunct to Stress Testing. This study was performed to evaluate the agreement between MCE and technetium 99m–sestamibi single photon emission computed tomography (SPECT) for detection of perfusion defects and to investigate whether quantitative assessment of myocardial perfusion can increase the diagnostic value of MCE. Methods MCE was performed at rest and during peak adenosine Stress in 50 unselected patients undergoing SPECT imaging. Concordance between the 2 methods was assessed using κ statistics. MCE images were analyzed quantitatively, measuring peak intensity (A) and maximal rise of signal intensity (β). Myocardial blood flow reserve was estimated by calculating the ratios of A adenosine /A baseline (A reserve), β adenosine /β baseline (β reserve), and A × β adenosine /A × β baseline (A × β reserve). Results Visual analysis of MCE agreed well with SPECT (κ = 0.67) with sensitivity of 64%, specificity of 97%, and overall accuracy of 87%. Quantitative analysis showed that peak signal intensity A significantly increased under adenosine Stress in SPECT-normal segments (2.6 ± 1.9 vs 3.0 ± 1.6 dB, P P = .07) and remained unchanged in fixed (0.9 ± 0.9 vs 0.8 ± 0.9 dB) defects. β Increased markedly under adenosine in normal segments (0.4 ± 0.4 vs 1.4 ± 1.3, P Conclusion Quantitative estimation of myocardial blood flow reserve by MCE parameters corresponds to the evaluation of myocardial perfusion by nuclear imaging and can increase the sensitivity but not the overall accuracy of contrast echocardiography.
Hugo A Katus - One of the best experts on this subject based on the ideXlab platform.
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real time myocardial perfusion imaging for Pharmacologic Stress Testing added value to single photon emission computed tomography
American Heart Journal, 2006Co-Authors: Grigorios Korosoglou, Alaineric Dubart, Gaspar K C Dasilva, Nino Labadze, Stefan E Hardt, Alexander Hansen, Raffi Bekeredjian, Christian Zugck, Joerg Zehelein, Hugo A KatusAbstract:Background Little is known about the incremental value of real-time myocardial contrast echocardiography (MCE) as an adjunct to Pharmacologic Stress Testing. This study was performed to evaluate the diagnostic value of MCE to detect abnormal myocardial perfusion by technetium Tc 99m sestamibi–single photon emission computed tomography (SPECT) and anatomically significant coronary artery disease (CAD) by angiography. Methods Myocardial contrast echocardiography was performed at rest and during vasodilator Stress in consecutive patients (N = 120) undergoing SPECT imaging for known or suspected CAD. Myocardial opacification, wall motion, and tracer uptake were visually analyzed in 12 myocardial segments by 2 pairs of blinded observers. Concordance between the 2 methods was assessed using the κ statistic. Results Of 1356 segments, 1025 (76%) were interpretable by MCE, wall motion, and SPECT. Sensitivity of wall motion was 75%, specificity 83%, and accuracy 81% for detecting abnormal myocardial perfusion by SPECT (κ = 0.53). Myocardial contrast echocardiography and wall motion together yielded significantly higher sensitivity (85% vs 74%, P P P Conclusion Assessment of myocardial perfusion adds value to conventional Stress echocardiography by increasing its sensitivity for the detection of functionally abnormal myocardial perfusion. Myocardial contrast echocardiography and wall motion together provide higher sensitivity and accuracy for detection of CAD compared with SPECT.