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January 1966

The Components of Electrical Diastole and Systole Against the Heart Cycle Time

Author Affiliations


From the Istituto di Fisiologia Umana, Via L. Mangiagalli, 32, Milano.

Arch Intern Med. 1966;117(1):70-73. doi:10.1001/archinte.1966.03870070084012

THE ELECTRICAL activity of the ventricular myocardium, ie, ventricular electrical systole, is assumed to begin with the Q wave of the ECG and end with the T wave.

The time between the end of the T and the beginning of the following Q wave, ie, the ventricular electrical diastole, is defined as the resting time of the ventricles.

The correlation between the QT interval and the heart cycle time has been suggested as a quadratic function by Bazett1 and Heggling and Holzmann,2 as a cubic one by Fridericia3 and Schlomka and Raab,4 as a linear one by Lombard and Cope5 and Adams.6

The statistical analyses performed by Sandera,7 Brambilla and Margaria,8 and Simonson9 on representative populations have recently confirmed the linear correlation: this is, as defined by Simonson and based on observations on nearly 1,000 subjects:

1. QT= (242.3+0.0003 years)+0.14 t±16msec where t is the heart cycle time.