The implantable antitachycardia therapy device,17, wherein {HEAD ~ the threshold detection means} includes {TAIL ~ means} for detecting in which of a plurality of rate zones the heart rate lies 
includes
The implantable antitachycardia therapy device,17 , wherein { HEAD ~ the threshold detection means } includes { TAIL ~ means } for detecting in which of a plurality of rate zones the heart rate lies
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH