Correlation between paced epimyocardial electrograms and stroke volume in heart transplants

In 10 heart transplant patients different hemodynamic states have been forced by randomized changes of pacing rate (PR) and postural variations (overall 40, 4/spl plusmn/1 per patient). Cardiac output assessed with thermodilution technique was compared to the ventricular evoked response (VER) recorded with telemetric pacemakers from epimyocardial leads. Linear regression analysis between the negative extremum during the depolarization phase of the VER (R/sub amp/) and the stroke volume (SV=CO/PR) resulted in the equation: R/sub amp/[%]=140-0.4*SV[%] with r=0.89 and p<0.00001. This result confirms previously reported results of a distinct relation between the negative extremum of paced epimyocardial ECGs and geometrical variations of the heart.