This MedLibrary.org supplementary page on Chronotropic is provided directly from the open source Wikipedia as a service to our readers. Please see the note below on authorship of this content, as well as the Wikipedia usage guidelines. To search for other content from our encyclopedia supplement, please use the form below:
Related Sponsors
Chronotropic effects (from chrono-, meaning time) are those that change the heart rate.
Chronotropic drugs may change the heart rate by affecting the nerves controlling the heart, or by changing the rhythm produced by the sinoatrial node. Positive chronotropes increase heart rate; however, negative chronotropes decrease heart rate.
A dromotrope affects Atrioventricular node (AV node) conduction. A positive dromotrope increases AV nodal conduction, and a negative dromotrope decreases AV nodal conduction. A lusitrope is an agent that affects diastolic relaxation.
Many positive inotropes affect preload and afterload.
Negative Chronotropes
Chronotropic variables in systolic myocardial performance can be split left and right. Left sided systolic chronotropy can be appreciated as Aortic Valve open to close time. Right sided variables are represented by Pulmonary valve open to close time. Inverted as diastolic chronotropy, the variables are aortic valve close to open and pulmonic close to open time. Pharmaceutical manipulation of chronotropic properties was perhaps first appreciated by the introduction of digitalis.
Positive Chronotropes
 |
This medical article is a stub. You can help Wikipedia by expanding it. |
 |
This pharmacology-related article is a stub. You can help Wikipedia by expanding it. |
|
|||||||||||||||||
Wikipedia content modification information:
- This page was last modified on 30 June 2008, at 21:55.
Wikipedia Authorship and Review
Wikipedia content provided here is not reviewed directly by MedLibrary.org. Wikipedia content is authored by an open community of volunteers and is not produced by or in any way affiliated with MedLibrary.org.
Wikipedia Usage Guidelines
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article on "Chronotropic".
The URL for this specific entry is:
All Wikipedia text is available under the terms of the GNU Free Documentation License. (See Copyrights for details). Wikipedia® is a registered trademark of the Wikimedia Foundation, Inc.