THE CARDIAC CYCLE
The rhythmic contraction of the heart is called heartbeat. A cardiac cycle is defined as a complete cardiac movement, including systole, intervening pause, and diastole. The cardiac cycle begins with depolarization of the SA node and atrial contraction. Each cycle requires a certain length of time for its completion. Pressure, volume, electrical, and sound changes occur during each cycle. Heart sounds are created primarily from turbulence in blood flow created by valves closing, not from contraction.
Know more: http://en.wikipedia.org/wiki/Cardiac_cycle
I also recommend this website for references regardless cardiology
http://www.nuclearcardiologyseminars.net/index.htm
But in the end so simple, after all simplicity is a puzzle of complexity.
ReplyDelete