A Wiggers diagram, named after its developer, Dr. Carl J. Wiggers, is a standard diagram that is used in teaching cardiac physiology. In the Wiggers diagram, the X-axis is used to plot time, while the Y-axis contains all of the following on a single grid:
- Blood pressure
- Ventricular volume
- Arterial flow (optional)
- Heart sounds (optional)
The Wiggers diagram clearly illustrates the coordinated variation of these values as the heart beats, assisting one in understanding the entire cardiac cycle.
|Phase||EKG||Heart sounds||Semilunar valves||Atrioventricular valves|
|B||Ventricular systole - Isovolumetric/isovolumic contraction||QRS||S1 ("lub")||closed||closed|
|C1||Ventricular systole - Ejection 1||-||open||closed|
|C2||Ventricular systole - Ejection 2||T||open||closed|
|D||Ventricular diastole - Isovolumetric/isovolumic relaxation||-||S2 ("dub")||closed||closed|
|E1||Ventricular diastole - Ventricular filling 1||-||S3*||closed||open|
|E2||Ventricular diastole - Ventricular filling 2||-||closed||open|
- S3 and S4 heart sounds are associated with pathologies and are not routinely heard.