title: Rapid quantitative assessment of myocardial perfusion: spectral analysis of myocardial contrast echocardiographic images.
abstract: We described a novel rapid spectral analysis technique performed on raw digital in-phase quadrature (IQ) data that quantitatively differentiated perfused from nonperfused myocardium based on the simultaneous comparison of local fundamental and harmonic frequency band intensity levels. In open-chest pigs after ligation of the left anterior descending coronary artery (LAD) and continuous venous contrast infusion, the fundamental-to-harmonic intensity ratio (FHIR) for samples placed within the left ventricular (LV) cavity (10.8 +/- 1.7 dB) and perfused myocardium (13.7 +/- 1.6 dB) were significantly (P <.001) lower than for nonperfused myocardium (27.1 +/- 2.9 dB). In attenuated images, the FHIR for the LV cavity and perfused myocardium were also significantly (P <.05) lower than for the nonperfused myocardium (21.4 +/- 3.0 dB, 34.4 +/- 3.2 dB, and 40.2 +/- 4.4 dB, respectively). Spectral properties of contrast microbubbles, as characterized by the FHIR, allow for rapid quantitative assessment of myocardial perfusion from data contained in a single-image frame, without requiring background image subtraction and image averaging.
authors.affiliation: Division of Cardiovascular Diseases and Internal Medicine and the Department of Physiology and Biophysics, Mayo Clinic and Foundation, Rochester, Minnesota 55905, USA.
authors.forename: Richard Y
authors.initials: RY
authors.lastname: Bae
authors.forename: Marek
authors.initials: M
authors.lastname: Belohlavek
authors.forename: James F
authors.initials: JF
authors.lastname: Greenleaf
authors.forename: James B
authors.initials: JB
authors.lastname: Seward
mesh_terms: D000208:Acute Disease; D000818:Animals; D003327:Coronary Disease / Q000000981:diagnostic imaging; D004195:Disease Models, Animal; D004452:Echocardiography; D022062:Electrophysiologic Techniques, Cardiac; D007091:Image Processing, Computer-Assisted; D008955:Models, Cardiovascular; D009206:Myocardium / Q000648:ultrastructure*; D010477:Perfusion; D013552:Swine