Implantable multi-axis position and activity sensor

A sensor for detecting the onset of tachycardia comprising:

• a. first means for detecting whether the patient is in a generally supine position;
• b. second means for detecting whether the patient's activity level is below a predetermined minimum value;
• c. third means for detecting cardiac intrinsic activities above a predetermined maximum value;
• and
• d. means for diagnosing the onset of tachycardia when said first detecting means indicates that the patient is in a generally supine position, when said second detecting means indicates that the patient's activity level is below said minimum value, and when said third detecting means indicates that the cardiac intrinsic activities are above said maximum value.

A method for detecting the onset of tachycardia comprising the steps of:

• a. detecting whether the patient is in a supine position;
• b. detecting whether the patient's activity level is below a predetermined minimum value;
• c. detecting cardiac intrinsic activities above a predetermined maximum value;
• and
• d. diagnosing the onset of tachycardia when the patient is in a generally supine position, when the patient's activity level is detected to be below said minimum value, and when the cardiac intrinsic activities are detected to be above said maximum value.