title: Ultraharmonic myocardial contrast imaging: in vivo experimental and clinical data from a novel technique.
abstract: Myocardial contrast echocardiography (MCE) with high-mechanical-index (MI), triggered harmonic imaging is the best-established technique to date for the assessment of myocardial perfusion. A high signal-to-noise ratio, which is significantly influenced by precontrast tissue signals, is an important prerequisite. Our goal was to evaluate the efficacy of ultraharmonic MCE, a technique that rejects tissue signals by receiving signals beyond the second but below the third harmonic. Imaging was performed in 6 closed-chest dogs and in 15 healthy volunteers (11 of whom also had dipyridamole stress). Analyses of videointensity (VI) confirmed uniformly low precontrast tissue VI, a significant increase of postcontrast VI (before and after dipyridamole), and a significant decrease in VI after microbubble destruction. We conclude that ultraharmonic MCE produces low precontrast tissue signals, thus optimizing postcontrast myocardial opacification, and exhibits efficient microbubble destruction with use of multiple-frame triggering. Thus this new technique opens up a new possibility of further optimizing coronary microcirculation imaging with microbubbles.
authors.affiliation: Department of Internal Medicine, Division of Cardiology, University of Michigan Health System, Ann Arbor, USA.
authors.forename: B
authors.initials: B
authors.lastname: Kuersten
authors.forename: T H
authors.initials: TH
authors.lastname: Murthy
authors.forename: P
authors.initials: P
authors.lastname: Li
authors.forename: Z
authors.initials: Z
authors.lastname: Liu
authors.forename: E
authors.initials: E
authors.lastname: Locricchio
authors.forename: C
authors.initials: C
authors.lastname: Baisch
authors.forename: P
authors.initials: P
authors.lastname: Rafter
authors.forename: M
authors.initials: M
authors.lastname: Vannan
mesh_terms: D000328:Adult; D000818:Animals; D003287:Contrast Media / Q000008:administration & dosage*; D003326:Coronary Circulation / Q000502:physiology; D003327:Coronary Disease / Q000000981:diagnostic imaging; D004176:Dipyridamole; D004285:Dogs; D004452:Echocardiography / Q000379:methods*; D005260:Female; D005466:Fluorocarbons / Q000008:administration & dosage; D006801:Humans; D007089:Image Enhancement; D008297:Male; D008863:Microspheres; D010726:Phosphodiesterase Inhibitors; D014465:Ultrasonics
chemical_list: D003287:Contrast Media; D005466:Fluorocarbons; D010726:Phosphodiesterase Inhibitors; D004176:Dipyridamole; C108042:perfluorobutane; C042852:perflutren