Patent ID: 7899522
Filing Date: 2011-03-01
Classification: A61B,A61N

Abstract:
1. A method for evaluating heart failure within a patient using an implantable medical device, the method comprising: detecting changes, if any, in cardiac electrical signals indicative of heart failure within the patient; detecting changes, if any, in transthoracic impedance values indicative of heart failure within the patient; and distinguishing between acute and chronic heart failure, if occurring within the patient, based on detected changes in the cardiac electrical signals and the transthoracic impedance values, wherein acute heart failure is relatively short term as compared to chronic heart failure; wherein distinguishing between acute and chronic heart failure within the patient includes (a) generating an indication of acute heart failure if the cardiac signals indicate the presence of heart failure whereas the impedance values exhibit little or no net change in value and (b) generating an indication of chronic heart failure if the impedance values indicate the presence of heart failure whereas the cardiac signals exhibit little or no net change in value.