NUR 259 Lecture Notes - Lecture 10: Atrial Flutter, Atrial Fibrillation, Dromotropic
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In addition, this drug alters how fast (rate) the heart contracts and the speed of how electrical impulses are sent through the heart"s electrical conduction system. So, in other words, this drug will alter the following actions in the heart: inotropic action: strength of contractions chronotropic action: rate the heart beats dromotropic action: speed of how electrical impulses are sent through the heart. In either a positive or negative way! (hint: remember this) Positive inotropic action: causes the heart muscle to squeeze or contract stronger. Negative chronotropic action: causes the heart to beat slower. Negative dromotropic action: slows down the impulses sent through the av node. When you combine these actions together it will create: a heart that squeezes blood out more efficiently (hence, less back flowing of blood). This will increase stroke volume (the amount of blood leaving the ventricle with each beat), which will increase cardiac output (the amount of blood pumped by the heart each minute).
