The authors studied the values of stroke volume, obtained through uniplanar cineventriculography and thermodilution, with the purpose of determining the feasibility of these methods for evaluating the regurgitated volume. Statistical analysis of the results shows that the two methods are not comparable. The difference of the values was attributed to the methodology of each technique mainly that they can not be used simultaneously. The authors conclude that the techniques proposed for measuring the regurgitated volume are not comparable, when using cineventriculography and thermodilution.336419422