Medical diagnostic apparatus for cardiovascular disease; medical diagnostic apparatus for vascular disease; medical diagnostic apparatus for arrhythmia; medical diagnostic apparatus for measuring physiological parameters in organs; computerized medical recording and analysis apparatus for the diagnosis and treatment of arrhythmias; medical instruments to measure blood pressure, cardiac output and other physiological and cardiovascular parameters; medical instruments for recording heart activity; medical apparatus and instruments for treating heart failure disease; heart stimulators for treating heart failure disease; heart stimulators for treating arrhythmia; artificial cardiac shunts; implantable sensors for sensing parameters of cardiac activity; medical implants comprised of artificial materials; intravascular catheter; subcutaneous catheter; electrodes for medical use; medical pulse generator leads for cardiac stimulations; medical pulse generator leads; medical apparatus for measuring physiological parameters in organs; surgical apparatus and instruments for heart; balloon catheters; wearable monitors used to measure biometric data for medical use; medical apparatus for measuring heartbeat; medical guidewires; medical electrode leads