Systolic rebound stretch during exercise

Abstract

Cardiac resynchronization therapy (CRT) is an established therapy for patients with heart failure. However, only 70% of the treated patients show improved exercise performance and quality of life. We hypothesize that septal deformation during exercise echocardiography can be used to predict cardiac resynchronization therapy response. This study focuses on the feasibility of exercise echocardiography. In 20 patients heart failure patients the longitudinal septal strain is assessed by speckle tracking echocardiography at rest and an exercise level corresponding to 30%, 60% and 90% of the ventilatory threshold. To investigate the effects of dyssynchronous activation of septal and left ventricular free wall and exercise on septal deformation pattern, we used the CircAdapt computer model of the human heart and circulation. The clinical data shows promising results, but additional steps are needed before the exercise protocol can be used in clinical practice. The model showed that systolic rebound stretch measurements during exercise, provides additional information, compared to measurements under resting condition. At an exercise level of 80%, different degrees of left ventricular free wall dyssynchrony can be distinguished easier than during rest. This can help distinguish CRT responders and non-responders.

Date of Award	28 Feb 2015
Original language	English
Supervisor	P.F.F. Wijn (Coach)