The efficacy of cardiac resynchronization therapy applied to a patient's
heart by an implantable device are improved by obtaining acute
hemodynamic feedback during implantation of a pacing device. A first and
a second transducer are temporarily placed proximate to a portion of the
patient's heart during device implant, and a distance between the
transducers is monitored as the therapy is applied. A parameter (e.g.
lead location, biventricular pacing, pacing rate, or the like) of the
cardiac therapy is adjusted in response to the distance between the
transducers until a desired result is obtained, after which the first and
second transducers can be removed from the patient.