Definition Lusitropy refers to the ability of the myocardium to relax following excitation contraction coupling. The removal of calcium to the endoplasmic reticulum (SR) promotes relaxation. The sarcoplasmic reticulum calcium ATPase (SERCA), NA/CA exchanger (NCX) and sarcolema CA-ATPase account for 90% removal of calcium. In essence, lusitropy is diastolic function as inotropy (or contractility) is […]