title: Assessment of myocardial viability in prior myocardial infarction by intravenous bolus microbubble injection: a new time domain index to estimate regional relative myocardial blood volume.
abstract: We tested whether the duration of myocardial opacification by harmonic power Doppler imaging after intravenous bolus microbubble injection (with a definition of "the end of opacification") would reflect the remaining vascular bed in infarcted segments. In 28 patients with previous myocardial infarction and 20 control patients, we performed harmonic power Doppler imaging after intravenous bolus injection of 1.5 g of Levovist. Using multiframe trigger mode in which 4 consecutive frames were imaged at every sixth end systole, which formed 1 "burst," we recorded anterior/septal and inferior/posterior walls separately on the center of each apical view with individual boluses. The duration of segmental opacification was measured as the number of "bursts" in which color signals persisted until the fourth frame. The duration was similar between the anterior/septal and inferior/posterior walls (13 +/- 3 vs 13 +/- 3 bursts, not significant) in the control group. In myocardial infarction patients, the duration was significantly shorter in the infarcted than in the control segments (6 +/- 6 vs 14 +/- 3 bursts, P < .001) and their ratio and difference exhibited significant correlations (r = 0.82, P < .001 and r = 0.91, P < .001, respectively) with the activity ratio on thallium Tl 201 single-photon emission computed tomography at rest. Thus, the duration of opacification by harmonic power Doppler imaging after intravenous bolus microbubble injection, the measurement of which was standardized by using multiframe trigger mode, may be useful in assessing regional myocardial viability in patients with previous myocardial infarction.
authors.affiliation: Second Department of Internal Medicine, Kagawa Medical University, Kita-Gun, Kagawa, Japan.
authors.forename: Kazushi
authors.initials: K
authors.lastname: Yukiiri
authors.forename: Koji
authors.initials: K
authors.lastname: Ohmori
authors.forename: Isao
authors.initials: I
authors.lastname: Kondo
authors.forename: Kojiro
authors.initials: K
authors.lastname: Tanimoto
authors.forename: Yasuyoshi
authors.initials: Y
authors.lastname: Iwado
authors.forename: Akira
authors.initials: A
authors.lastname: Oshita
authors.forename: Yu
authors.initials: Y
authors.lastname: Yang
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Wada
authors.forename: Katsufumi
authors.initials: K
authors.lastname: Mizushige
authors.forename: Masakazu
authors.initials: M
authors.lastname: Kohno
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003287:Contrast Media; D003326:Coronary Circulation; D004452:Echocardiography / Q000379:methods*; D005260:Female; D006801:Humans; D007275:Injections, Intravenous; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000000981:diagnostic imaging*; D009206:Myocardium / Q000473:pathology; D015588:Observer Variation; D011134:Polysaccharides / Q000008:administration & dosage*; D015899:Tomography, Emission-Computed, Single-Photon
chemical_list: D003287:Contrast Media; D011134:Polysaccharides; C059891:SHU 508