Wiggers diagram



A Wiggers diagram is a standard diagram used in cardiac physiology.

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


 * Blood pressure
 * Aortic pressure
 * Ventricular pressure
 * Atrial pressure
 * Ventricular volume
 * Electrocardiogram
 * Arterial flow (optional)
 * Heart sounds (optional)

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

Etymology
It is named after Carl J. Wiggers. (The diagram is frequently incorrectly called a "Wigger's diagram". Although "Wiggers' diagram" would be grammatically correct, it is more frequently rendered "Wiggers diagram", with no apostrophe.)

Events
Note that during isovolumetric/isovolumic contraction and relaxation, all the heart valves are closed. At no time are all the heart valves open.
 * S3 and S4 heart sounds are associated with pathologies and are not routinely heard.