Implantable medical device

An implantable medical device comprising a processor and a memory unit, wherein the memory unit comprises a computer-readable program that causes the processor to perform the following steps when run on the processor:

• a) performing a detection to determine that the implantable medical device is in an implanted state;
• and
• b) activating a first diagnostic or therapeutic function of the implantable medical device, and subsequently activating a second diagnostic or therapeutic function of the implantable medical device, wherein the second diagnostic or therapeutic function is activated only after the fulfilment of:
• i) a passing of a function test;
• and ii) at least one of an elapse of a first time period from the activation of the first diagnostic or therapeutic function or an elapse of a second time period from the detection that the implantable medical device is in an implanted state;
• wherein the first diagnostic or therapeutic function and/or the second diagnostic or therapeutic function comprises a function for cardiac defibrillation, a function for antitachycardia stimulation of a cardiac region of a patient and/or a function for the automatic adaptation of algorithms used for antitachycardia stimulation.