Effect of myocardial contractility on hemodynamic end points under concomitant microvascular disease in a porcine model

Heart Vessels. 2014 Jan;29(1):97-109. doi: 10.1007/s00380-013-0355-9. Epub 2013 Apr 30.

Abstract

In this study, coronary diagnostic parameters, pressure drop coefficient (CDP: ratio of trans-stenotic pressure drop to distal dynamic pressure), and lesion flow coefficient (LFC: ratio of % area stenosis (%AS) to the CDP at throat region), were evaluated to distinguish levels of %AS under varying contractility conditions, in the presence of microvascular disease (MVD). In 10 pigs, %AS and MVD were created using angioplasty balloons and 90-μm microspheres, respectively. Simultaneous measurements of pressure drop, left ventricular pressure (p), and velocity were obtained. Contractility was calculated as (dp/dt)max, categorized into low contractility <900 mmHg/s and high contractility >900 mmHg/s, and in each group, compared between %AS <50 and >50 using analysis of variance. In the presence of MVD, between the %AS <50 and >50 groups, values of CDP (71 ± 1.4 and 121 ± 1.3) and LFC (0.10 ± 0.04 and 0.19 ± 0.04) were significantly different (P < 0.05), under low-contractility conditions. A similar %AS trend was observed under high-contractility conditions (CDP: 18 ± 1.4 and 91 ± 1.4; LFC: 0.08 ± 0.04 and 0.25 ± 0.04). Under MVD conditions, similar to fractional flow reserve, CDP and LFC were not influenced by contractility.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Blood Flow Velocity
  • Coronary Artery Disease / diagnosis
  • Coronary Artery Disease / physiopathology*
  • Coronary Stenosis / diagnosis
  • Coronary Stenosis / physiopathology*
  • Coronary Vessels / physiopathology*
  • Disease Models, Animal
  • Fractional Flow Reserve, Myocardial*
  • Hemodynamics*
  • Microcirculation*
  • Myocardial Contraction*
  • Severity of Illness Index
  • Swine
  • Ventricular Function, Left*
  • Ventricular Pressure