Kawataki M, Kashima T, Toda H, Tanaka H
J Electrocardiol. 1984 Oct;17(4):371-5. doi: 10.1016/s0022-0736(84)80074-6.
We studied the relationship between QT interval and RR interval when the heart rate was changed by atrial pacing, atropine, isoproterenol, and exercise in nine healthy adult males. The following results were obtained: (1) QT shortening with an increase in heart rate was minimal in atrial pacing and an equation QT = k4 square root RR was obtained from the QT-RR relationship during atrial pacing (r = 0.64, p less than 0.001); (2) shortening of QT with shortening of RR was least in atrial pacing; (3) during recovery from exercise it was largest and almost coincident with Bazett's formula; (4) Bazett's formula, therefore, is clearly applicable in the evaluation of ECGs recorded at rest or after exercise; (5) Bazett's formula can not be applied in the evaluation of an effect of some drug or maneuver on the QT when such a drug or maneuver can affect both the QT and the RR directly. The RR-dependent QT change can be estimated from the equation QT = k4 square root RR and the difference between a measured QT and the estimated RR-corrected QT would be a genuine effect of the drug or maneuver on the QT at that heart rate. We conclude that atropine, isoproterenol and exercise actually shorten the QT interval.
我们研究了在9名健康成年男性中，通过心房起搏、阿托品、异丙肾上腺素和运动改变心率时QT间期与RR间期之间的关系。得到以下结果：(1) 心房起搏时，心率增加导致的QT缩短最小，且从心房起搏期间的QT-RR关系中得到方程QT = k4√RR（r = 0.64，p < 0.001）；(2) 心房起搏时，RR缩短导致的QT缩短最少；(3) 运动恢复期间，QT缩短最大且几乎与Bazett公式一致；(4) 因此，Bazett公式显然适用于评估静息或运动后记录的心电图；(5) 当某种药物或操作能直接影响QT和RR时，Bazett公式不能用于评估该药物或操作对QT的影响。RR依赖性QT变化可根据方程QT = k4√RR估算，测量的QT与估算的RR校正QT之间的差异将是该心率下药物或操作对QT的真实影响。我们得出结论，阿托品、异丙肾上腺素和运动实际上会缩短QT间期。
