Extrasystole a premature cardiac contraction that is independent of the normal rhythm and arises in response to an impulse outside the sinoatrial node. AM八f 八AA /个 Compensatory pause The pause following an extrasystole,when the pause is long enough to compensate for the prematurity of the extrasystole; the short cycle ending with the extrasystole plus the pause following the extrasystole together equal two of the regular cycles.Extrasystole  a premature cardiac contraction that is independent of the normal rhythm and arises in response to an impulse outside the sinoatrial node. Compensatory pause  The pause following an extrasystole, when the pause is long enough to compensate for the prematurity of the extrasystole;  the short cycle ending with the extrasystole plus the pause following the extrasystole together equal two of the regular cycles