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.