title: Echocardiographic assessment of regional ventricular function after device-based change of left ventricular shape.
abstract: We assessed the effects of implantation of Myosplint (Myocor, Maple Grove, Minn), a device that changes left ventricular (LV) cross-sectional shape from circular to bilobar, on regional LV function. A total of 10 open-chest dogs with tachycardia-induced cardiomyopathy were studied before and after Myosplint implantation. LV cross-sectional epicardial echocardiography at the papillary muscle level was performed along with acquisition of hemodynamic data. LV normalized thickening, fractional thickening, end-diastolic thickness, and end-diastolic curvatures were calculated for 10 LV segments. Myosplint implantation did not affect LV hemodynamics, but decreased average end-diastolic curvature (P <.0001) and increased its segmental heterogeneity (P <.0001). There was no change in average fractional thickening, whereas normalized thickening increased (P =.05). In contrast, segmental heterogeneity of both normalized and fractional thickening increased (P =.02 and P =.01, respectively). Structural modeling confirmed that Myosplint implantation increases regional stress heterogeneity and curvature heterogeneity. LV cross-sectional shape markedly affects regional LV performance.
authors.affiliation: Department of Cardiovascular Medicine, The Cleveland Clinic Foundation, OH 44195, USA.
authors.forename: Zoran B
authors.initials: ZB
authors.lastname: Popović
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Saracino
authors.forename: Dimitri
authors.initials: D
authors.lastname: Deserranno
authors.forename: Hua
authors.initials: H
authors.lastname: Yang
authors.forename: Neil L
authors.initials: NL
authors.lastname: Greenberg
authors.forename: Masami
authors.initials: M
authors.lastname: Takagaki
authors.forename: Kiyotaka
authors.initials: K
authors.lastname: Fukamachi
authors.forename: Yoshie
authors.initials: Y
authors.lastname: Ochiai
authors.forename: Masahiro
authors.initials: M
authors.lastname: Inoue
authors.forename: Soren
authors.initials: S
authors.lastname: Schenk
authors.forename: Kazuyoshi
authors.initials: K
authors.lastname: Doi
authors.forename: Jianxin
authors.initials: J
authors.lastname: Qin
authors.forename: Patrick M
authors.initials: PM
authors.lastname: McCarthy
authors.forename: Takahiro
authors.initials: T
authors.lastname: Shiota
authors.forename: James D
authors.initials: JD
authors.lastname: Thomas
mesh_terms: D000818:Animals; D009202:Cardiomyopathies / Q000000981:diagnostic imaging* / Q000473:pathology / Q000503:physiopathology*; D004285:Dogs; D006353:Heart-Assist Devices; D008955:Models, Cardiovascular; D014463:Ultrasonography; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging* / Q000473:pathology / Q000503:physiopathology*