Patent ID: 8914108

Claim:
A system, comprising: at least one implantable lead comprising at least one electrode; at least one pulse generator coupleable to the at least one lead and configured to deliver cardiac stimulation to pacing sites adjacent the at least one electrode; at least one sensing circuit configured to obtaining a signal indicative of electrical activity of the patient's heart; at least one plethysmograph sensor configured to obtain a plethysmograph signal indicative of changes in arterial blood volume; and at least one processor for use in selecting a pacing site at which to deliver cardiac stimulation to a patient; wherein for each of a plurality of pacing sites and/or combination of pacing sites within the patient, the system is configured to use the at least one lead, the at least one pulse generator, the at least one sensing circuit, and the at least one processor, to deliver cardiac stimulation using the pacing site or the combination of pacing sites; obtain the signal indicative of electrical activity of the patient's heart while the pacing site or the combination of pacing sites is being used to deliver cardiac stimulation; obtain the plethysmograph signal indicative of changes in arterial blood volume while the pacing site or the combination of pacing sites is being used to deliver cardiac stimulation; and determine a time delay between a predetermined feature of the signal indicative of electrical activity and a predetermined feature of the plethysmograph signal indicative of changes in arterial blood volume; and wherein the system is also configured to select a pacing site or a combination of pacing sites, from the plurality of pacing sites, based on the time delays.