Article Text

other Versions

PDF
Load-sensitivity of regional tissue deformation in the right ventricle: isovolumic versus ejection-phase indices of contractility.
  1. Carlo Missant (carlo.missant{at}med.kuleuven.ac.be)
  1. Katholieke Universiteit Leuven, Belgium
    1. Steffen Rex (srex{at}ukaachen.de)
    1. University Hospital RWTH Aachen, Germany
      1. Piet Claus (piet.claus{at}uz.kuleuven.ac.be)
      1. Katholieke Universiteit Leuven, Belgium
        1. Luc Mertens (luc.mertens{at}uz.kuleuven.ac.be)
        1. Katholieke Universiteit Leuven, Belgium
          1. Patrick F Wouters (patrick.wouters{at}uz.kuleuven.ac.be)
          1. Katholieke Universiteit Leuven, Belgium

            Abstract

            Objective: Doppler myocardial imaging is increasingly being used to evaluate regional and global cardiac function. Quantitative measurements of tissue deformation obtained during ejection as well as isovolumic contraction have been proposed as new indices of contractility, however, their load-sensitivity remains a matter of controversy. We compared maximum strain rate (SRmax) and isovolumic strain acceleration (ISAmax) with regard to sensitivity for inotropic state, heart rate and loading conditions in the right ventricle (RV), using pressure-volume analysis as the reference method.

            Design: Prospective Animal Study

            Setting: University Hospital Laboratory

            Interventions: RV contractility was measured at baseline, after inotropic modulation with esmolol and dobutamine, at different atrial pacing rates and during controlled alterations of RV pre- and afterload.

            Main outcome measures: RV contractility was assessed with the slope (Mw) of preload recruitable stroke work and longitudinal SRmax and ISAmax

            Results: SRmax and ISAmax reflected the drug-induced changes in contractility, while only ISAmax increased with higher pacing rates. Acute lowering of RV-preload did not affect either of the indices studied. In contrast, an increase in RV-afterload consistently decreased SRmax (from 1.05±0.41 to 0.73±0.26 s-1,p=0.03) but had variable effects on ISAmax and Mw. However, we found a significant correlation between proportional changes in ISAmax and Mw during high afterload conditions(r2=0.89,p=0.005).

            Conclusions: Both SRmax and ISAmax reflected changes in RV-contractility. ISAmax was less sensitive to changes in RV-afterload than SRmax and may therefore be a more robust index of global RV-contractility.

            Statistics from Altmetric.com

            Request permissions

            If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.

            Linked Articles