Assessment of normal and ischaemic myocardium by quantitative M-mode tissue Doppler imaging

This paper presents a methodology and a software package developed to quantify M-mode tissue Doppler imaging (TDI), defining a number of quantitative parameters drawn from velocity and gradient curves obtained after segmenting the myocardial wall into anatomical layers. The independent clinical predictive value of these parameters to detect motion abnormalities in the presence of ischaemia was evaluated in a comparative study between a group of 17 healthy volunteers and 18 ischaemic patients. Factor analysis and stepwise logistic regression were used to assess the independent predictive value of these parameters in detecting abnormal contractility of the basal posterior segment. The statistical analysis performed has proved that any single parameter related to the gradient intensity, particularly the maximum gradient at the moment of the "e" wave, provides meaningful clinical information, achieving a rate of correct classification of 79.1% on the same data set used for the analysis. Adding additional parameters does not improve the diagnostic performance. Further testing with different settings (stress studies, other pathologies or segments) is warranted.