Eficacia de la relación gradiente pico-gradiente medio para el diagnóstico de la gravedad de la estenosis aórtica

the aim of the present study was to evaluate the statistical efficacy of peak to mean pressure decrease ratio (gmax/ gmed) for the assessment of aortic stenosis severity. we studied the echocardiograms of 212 consecutive patients (mean age: 74 years; range: 19-98 years; 100 males [47%]) with an aortic area calculated by the continuity equation (aao) of 2 cm2. we considered severe aortic stenosis: a maximal aortic velocity (vmax) 4 m/s, a mean gradient (gmed) 40 mmhg or an aao of 1 cm2. we also performed the analysis taking an aao 0.75 cm2 as severe aortic stenosis. we conclude that: 1) gmax/ gmed ratio is directly but weakly correlated; 2) there is a great overlap among gmax/ gmed ratio values corresponding to patients with different aortic stenosis severity; 3) the sensitivity, specificity and accuracy of gmax/ gmed ratio for the diagnosis of severe aortic stenosis are of average magnitude; 4) the positive and negative predictive values of gmax/ gmed ratio are modest, in the studied population; 5) the analysis of likelihood ratios demonstrated that gmax/ gmed ratio has only a small clinical impact for the diagnosis of severe aortic stenosis; 6) more studies are needed before accepting gmax/ gmed ratio as a useful clinical parameter for the diagnosis of severe aortic stenosis. the gmax/ gmed ratio could be a surrogate criterion for aao when it is not possible to assess all the variables needed for its calculation.