(15,16)
Dyssynchrony is considered one of several mechanisms that RV pacing can
cause myocardial dysfunction. Pacing of RV apex leads to both
inter-ventricular and intra-ventricular dyssynchrony which in turn
reduces LV systolic function and leads to adverse clinical outcomes.(17) Long-term studies suggested that more
than 40% of RV pacing in rate modulated (DDDR) mode is predictive of
unfavorable events as HF hospitalization.