In some embodiments, an implantable medical device (IMD) system may include one or more of the following elements: (a) an oxygen sensor for measuring oxygen extraction from blood flowing through a coronary sinus of a patient's heart, (b) an oxygen signal generated by the oxygen sensor, (c) an IMD coupled...http://www.google.com.au/patents/US7904158?utm_source=gb-gplus-sharePatent US7904158 - Measurement of coronary sinus parameters to optimize left ventricular performance
