SEARCH Articles Figures Tables The TARP is the sum of the AVI and postventricular refractory period . The TARP defines the interval in which the shortest interval at which atrial activity is tracked because atrial events do not lead to atrial tracking during the TARP. In this case, the TARP is 400ms, the sum of the AV interval of 150ms and the PVARP of 250ms. [Publishers Imprint]