Window to the heart: the value of a native and paced QRS duration. Current perspective and review.

Given the technological advances and reliance upon expensive testing for guiding therapy, it is surprising how an inexpensive, low tech electrocardiogram can provide a wealth of information pertaining to the underlying cardiovascular status of a patient. In this article we review the changes in hemodynamics, prognosis and guidance of therapeutic options associated with a prolonged QRS duration.