Patient-specific models of dyssynchronous heart failure for assessment of regional work in patients undergoing cardiac resynchronization therapy

Cardiac resynchronization therapy (CRT) can improve the synchrony of contraction between the right and left ventricles in DHF and reduce morbidity and mortality and increase quality of life. However, regional work before CRT and changes with CRT are not well understood. We used three-dimensional multi-scale patient-specific computational models parameterized by anatomic, functional, hemodynamic, and electrophysiological measurements to assess changes in eight patients with heart failure and left bundle branch block (LBBB) who received CRT. To increase clinical translatability, we also explored the utility of streamlined methods to estimate regional myocardial work. We found that CRT increased global myocardial work efficiency with significant improvements in non-responders. Reverse ventricular remodeling after CRT was greatest in patients with the highest heterogeneity of regional work at baseline. Decreases in early-activated regions of myocardium performing negative myocardial work with CRT best explained patient variations in reverse remodeling. These findings were also observed when regional myocardial work was estimated using ventricular pressure as a surrogate for myocardial stress and changes in endocardial surface area as a surrogate for strain. These findings suggest that CRT promotes reverse ventricular remodeling in human dyssynchronous heart failure by increasing regional myocardial work in early-activated regions of the ventricles and that measurement of these changes can be performed using streamlined approaches.

Methods
We built three-dimensional multi-scale patient-specific computational models parameterized by anatomic, functional, hemodynamic, and electrophysiological measurements in eight patients with heart failure and left bundle branch block (LBBB) who received CRT.

To increase clinical translatability, we also explored whether streamlined computational methods provide accurate estimates of regional myocardial work.