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Background and Objective: Contrast echocardiography has been recently introduced as a new technique for evaluating myocardial perfusion in a qualitative basis. The objective of this study was to test whether a visual subjective evaluation of myocardial perfusion by myocardial contrast echocardiography adequately matches the data obtained with an off-line quantification of myocardial perfusion., Methods: Sixty-one myocardial segments were evaluated by myocardial contrast echocardiography with Ultra-harmonic and Multiframe Triggering in 11 patients 3-7 days after an anterior myocardial infarction, using SH-U 563A (Levovistâ, Schering AG, Berlin, Germany) as contrast agent. Myocardial perfusion was classified as grade 1 (absent), 2 (patchy or incomplete) and 3 (complete) in each segment. The quantitative analysis was performed off-line by a different investigator blinded to the qualitative evaluation, using a commercially available software. The quantitative data on grey-scale obtained were compared between grade 1, 2 and 3 segments., Results: Of the 61 segments, 45 (73.8%) were classified as grade 3, whereas the remaining 16 (26.2%) were considered to be abnormally perfused (grade 2: n=12, 19.6%; grade 1: n=4, 6.6%). Segments with grade 1 perfusion had a significantly higher grey-scale value (123.6 +/- 41.3 vs. 70.1 +/- 34.3, p=0.004). However, there were no significant differences between segments with perfusion grade 2 and 3 (76.8 +/- 33.2 vs. 68.3 +/- 34.8, p=0.452)., Conclusion: Qualitative assessment of myocardial perfusion by Ultra-harmonic and Multiframe Triggering is of limited value, since only myocardial segments with absent perfusion may be reliably identified. This findings support the need of quantification in the evaluation of myocardial perfusion by contrast echocardiography.

Background and Objectives: In addition to the myocardium, the microvasculature may be also damaged in acute myocardial infarction. The aim was to evaluate the capability of myocardial contrast echocardiography in the detection of microvasculature damage after myocardial infarction., Patients and Methods: Twelve patients with recent acute myocardial infarction and five control subjects with normal coronary arteries and without history of myocardial infarction were studied. Myocardial contrast echocardiography with power modulation was performed, and quantitative data were measured off-line. Power modulation uses a combination of low (0.1) and high (1.7) mechanical indexes, allowing a real-time evaluation of myocardial perfusion. Contrast agent was administered as a 3-min bolus. The quantitative analysis was performed off-line by a different blinded investigator. The refilling velocity was calculated as the difference between the peak myocardial refilling value and the value at 1 s after the impulse divided by the time from the first second after the impulse to the peak refilling value., Results: Eighty-one myocardial segments (75%) were analysed qualitatively and quantitatively in AMI patients, and 18 (60%) in control subjects (P=NS). The peak refilling intensity was not significantly different in patients and control subjects (6.62+/-5.85 vs. 7.53+/-4.06 dB, respectively). However, time to peak refilling intensity was significantly longer (5.25+/-1.57 vs. 4.00+/-0.53, P=0.004) and the velocity of refilling was significantly lower (2.74+/-5.34 vs. 6.58+/-8.02, P=0.028) in patients with myocardial infarction., Conclusion: There is microvasculature damage after myocardial infarction that is reflected as a delayed velocity of refilling in myocardial contrast echocardiography.