Torsion of the left ventricle during the ejection phase in the intact dog

摘要: Torsion of the left ventricle (LV) is associated with rotation apex respect to base around long axis LV. A mathematical model LV mechanics, which relates torsion transmural distribution fibre shortening, was evaluated two-dimensional echocardiography in nine anaesthetised closed-chest dogs. calculated as difference between angles (radians) echo-derived transverse cross-section projections obtained at mitral valve and low papillary level, divided by axial distance these measured a long-axis cross-section, multiplied outer radius mid-papillary projection shortening ratio (STR) defined inner wall occurring during ejection. In series 11 measurements, each based on frame-to-frame analysis 15 cardiac cycles, STR found be 2.31 +/- 0.23 rad-1 (mean SD), whereas predicted value 2.4 over wide range preload, afterload contractility levels. We conclude that validates presence normal canine ventricle, ventricular mechanics.