A "tracker system" that includes electrical leads which are part of an implanted cardiotracker plus external equipment that includes external alarm and a physician's programmer. The tracker system is designed to monitor the degradation of a patient's cardiovascular condition from one or more causes, These causes include the rejection of a transplanted heart and/or the progression of a stenosis in a coronary artery. As one or more stenoses in a coronary artery become progressively more narrow thereby causing reduced blood flow to the heart muscle coronary circulation, the tracker system can alert the patient by either or both internal and/or external alarm to take the appropriate medical action. The physician's programmer can be used to display histograms of key heart signal parameters that are indicative of the patient's cardiovascular condition.