Wiggers diagram

A Wiggers diagram is a standard diagram used in cardiac physiology named after Dr. Carl J. Wiggers.

The X axis is used to plot time, while the Y axis contains all of the following on a single grid:

By illustrating the coordinated variation of these values, it becomes easier to illustrate the relationship between these values in the cardiac cycle.

Note that during isovolumetric/isovolumic contraction and relaxation, all the heart valves are closed. At no time are all the heart valves open.

Ventricular systole

Cardiac diastole

ECG

The EKG complex. P=P wave, PR=PR interval, QRS=QRS complex, QT=QT interval, ST=ST segment, T=T wave

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