
{"publication_number": "US-6885892-B1", "abstract": "a rate adaptive pacemaker has a measuring unit which interacts with a patient to determine a demand , a pacing rate controller connected to the measuring unit for controlling the pacing rate in response to the demand , and a pacing rate limiter connected to the pacing rate controller which upwardly limits the pacing rate so as to always maintain the energy supplied to the myocardium at a level which exceeds the energy consumed by the myocardium .", "application_number": "US-93797101-A", "description": "as mentioned above , according to one embodiment of the pacemaker according to the invention an upper limit value for the pacing rate is determined based on a balance between the energy consumption of the myocardium and the energy supplied to the myocardium for high patient workloads . since the oxygen demand , or demanded energy consumption which is equal to the work of myocardium , is well correlated to the area s dem within the ventricular pressure - volume loop shown in fig1 a , the following equations are valid where w denotes the work of the myocardium , { overscore ( \u03b4 )