The work of the heart is decreased and coronary blood flow is increased to promote the formation of new coronary collateral channels and {HEAD ~ the perfusion} of {TAIL ~ the heart} itself 
of
The work of the heart is decreased and coronary blood flow is increased to promote the formation of new coronary collateral channels and { HEAD ~ the perfusion } of { TAIL ~ the heart } itself
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH