Myocardial Contrast Echocardiography in Acute Myocardial Infarction Using Aortic Root Injections of Microbubbles in Conjunction With Harmonic Imaging: Potential Application in the Cardiac Catheterization Laboratory

AbstractObjectives. The aim of this study was to evaluate myocardial contrast echocardiography using aortic root injections with harmonic imaging in experimental acute myocardial infarction to determine the potential of this approach in the cardiac catheterization laboratory.Background. It would be desirable to have an adjunctive procedure that could evaluate myocardial perfusion at the time of cardiac catheterization in patients with acute myocardial infarction. A single injection of contrast medium in the aortic root would provide complete information on myocardial perfusion in a cross section of the heart. High quality images would provide on-line assessment of myocardial perfusion without recourse to image processing. These data could be very valuable for determining patient management.Methods. Perfusion defects on myocardial contrast echocardiography were measured during coronary occlusion and reflow, using fundamental and harmonic imaging in both continuous and intermittent modes in nine open chest dogs. These defects were compared with risk area on technetium-99m autoradiography and infarct size on tissue staining.Results. Whereas harmonic imaging increased myocardial video intensity by more than twofold (p < 0.001) compared with fundamental imaging after aortic root injection of contrast medium, intermittent imaging was not superior to continuous imaging. The improved signal to noise ratio of harmonic imaging allowed on-line definition of risk area (r = 0.98) and infarct size (r = 0.93) without recourse to off-line processing. Similar results could be obtained with fundamental imaging only after off-line processing.Conclusions. Aortic root injections of contrast medium coupled with harmonic imaging can be used to provide accurate on-line assessment of risk area and infarct size during acute myocardial infarction. These results have important implications for the catheterization laboratory.(J Am Coll Cardiol 1997;29:207–16)

Analysis of myocardial perfusion or myocardial function for detection of regional myocardial abnormalities. An echocardiographic multicenter comparison study using myocardial contrast echocardiography and 2D echocardiography

Background: Echocardiography based myocardial perfusion imaging and regional wall motion analysis are used for evaluation of coronary artery disease and regional myocardial abnormalities. Aim: This study sought to compare myocardial contrast echocardiography (MCE) and 2D echocardiography with regard to interobserver variability and detection of regional myocardial abnormalities. Methods: In 70 patients evenly distributed between three ejection fraction groups based on biplane cineventriculography (>55%, 35-55%, <35%), unenhanced and contrast enhanced 2D echocardiography and myocardial contrast echocardiography (MCE; SonoVue (R); Bracco) were performed. Regional watt motion and myocardial perfusion were assessed referring to a 16 segment model.. Interobserver agreement (10A) among 2 readers was determined within each imaging modality. To define a standard of truth for the presence of segmental myocardial disease an independent expert-panel decision was obtained based on clinical data, ECG, coronary angiography and blinded information from the imaging modalities. Results: Regional wall motion assessment was possible in 98.1% of segments using contrast enhanced 2D echocardiography and in 87.2% using unenhanced 2D echocardiography (p < 0.001), while perfusion assessment was possible in 90.1% of segments (p < 0.001). 10A on presence of any regional wall motion abnormality expressed as Kappa coefficient was 0.71 (95% Cl 0.53-0.89) for contrast enhanced echocardiography and 0.37 (95% Cl 0.14-0.59) for unenhanced echocardiography. 10A on presence of any perfusion abnormality was 0.53 (95% Cl 0.34-0.73). For MCE there was high 10A for the apical segments (kappa = 0.57) and Lower 10A for the basal segments (kappa = 0.14), while no such gradient was found for the 10A on watt motion abnormalities. Mean accuracy to detect expert-pane[ defined myocardial abnormalities was 80.6% for unenhanced echocardiography, 85.0% for contrast enhanced 2D echocardiography and 80.6% for MCE. Conclusions: MCE is inferior to contrast enhanced 2D echocardiography with regard to visibility of all LV segments and appears slightly inferior with regards to 10A, white both are superior to unenhanced 2D echocardiography. The methods demonstrated high accuracy in detection of panel defined regional myocardial abnormalities. (C) 2006 The European Society of Cardiology. Published by Elsevier Ltd. All rights reserved

Analysis of regional left ventricular function by cineventriculography, cardiac magnetic resonance imaging, and unenhanced and contrast-enhanced echocardiography - A multicenter comparison of methods

OBJECTIVES To define the use of cineventriculography, cardiac magnetic resonance imaging (cMRI), and unenhanced and contrast-enhanced echocardiography for detection of left ventricular (LV) regional wall motion abnormalities (RWMA). BACKGROUND Detection of RWMA is integral to the evaluation of LV function. METHODS In 100 patients, cineventriculography and unenhanced and contrast-enhanced echocardiography were performed. Fifty-six of the patients underwent additional cMRI. RWMA were assessed referring to a 16-segment model for cMRI, unenhanced and contrast echocardiography. Cineventriculography was evaluated on a 7-segment model. Hypokinesia in one or more segments defined presence of RWMA. Interobserver agreement among three readers was determined within each imaging modality. Intermethod agreement between imaging modalities was analyzed. A standard of truth for the presence of RWMA was obtained by an independent expert panel decision (EPD) based on clinical data, electrocardiogram, coronary angiography, and blinded information from the imaging modalities. RESULTS Sixty-seven patients were found to have an RWMA by EPD. Interobserver agreement expressed as kappa coefficient was 0.41 (range 0.37 to 0.44) for unenhanced echocardiography, 0.43 (range 0.29 to 0.79) for cMRT, 0.56 (range 0.44 to 0.70) for cineventriculography, and 0.77 (range 0.71 to 0.88) for contrast echocardiography. Contrast enhancement compared to unenhanced echocardiography improved agreement of echocardiography related to cMRI (kappa 0.46 vs. 0.29) and related to cineventriculography (kappa 0.59 vs. 0.28). Accuracy to detect EPD-defined RWMA was highest for contrast echocardiography, followed by cMRI, unenhanced echocardiography, and cineventriculography. CONCLUSIONS Analysis of RWMA is characterized by considerable interobserver variability even using high-quality imaging modalities. lnterobserver agreement on RWMA and accuracy to detect panel-defined RWMA is good using contrast echocardiography

Mapping the population/service mismatch of Chronic Heart Failure in Australia

Tissue Doppler (TD) assessment of dysynchrony (DYS) is established in evaluation for bi-ventricular pacing. Time to regional minimal volume by real-time 3D echo (3D) has been applied to DYS. 3D offers simultaneous assessment of all segments and may limit errors in localization of maximum delay due to off-axis images.We compared TD and 3D for assessment of DYS. 27 patients with ischaemic cardiomyopathy (aged 60±11 years, 85% male) underwent TD with generation of regional velocity curves. The interval between QRS onset and maximal systolic velocity (TTV) was measured in 6 basal and 6 mid-cavity segments. Onthe same day,3Dwas performed and data analysed offline with Q-Lab software (Philips, Andover, MA). Using 12 analogous regional time-volume curves time to minimal volume (T3D)was calculated. The standard deviation (S.D.) between segments in TTV and T3D was calculated as a measure ofDYS. In 7 patients itwas not possible to measureT3D due to poor images. In the remaining 20, LV diastolic volume, systolic volume and EF were 128±35 ml, 68±23 ml and 46±13%, respectively. Mean TTV was less than mean T3D (150±33ms versus 348±54 ms; p 32 ms), S.D. T3D was 69±37ms compared to 48±34ms in those without DYS (p = ns). In DYS patients there was concordance of the most delayed segment in 4 (44%) cases.Therefore, different techniques for assessing DYS are not directly comparable. Specific cut-offs for DYS are needed for each technique