Why Ischemic Hearts Respond Less to Cardiac Resynchronisation Therapy. A Modeling Study

摘要

Cardiac Resynchronisation Therapy (CRT) by means of simultaneous biventricular or multisite leftventricular pacing is a new technique for improving left ventricular systolic performance in patients with heart failure and conduction abnormalities (e.g. left bundle branch block). However, different pathological cases do react differently to CRT and the underlying mechanisms are poorly understood. This paper presents a study of the mechanical effects of delayed activation on ejection and regional deformation using a simplified mathematical model. These effects are studied in normal and dilated hearts, and is-chemic non-dilated and dilated hearts. Prom these simulations we derive dependencies of regional performance parameters on delayed activation and discuss why ischemic hearts do respond less to CRT.