Dromotropic Explained

The term dromotropic derives from the Greek word δρόμος drómos, meaning "running", a course, a race. A dromotropic agent is one which affects the conduction speed (in fact the magnitude of delay^[1]) in the AV node, and subsequently the rate of electrical impulses in the heart.^{[2] [3]}

Positive dromotropy increases conduction velocity (e.g. epinephrine stimulation), negative dromotropy decreases velocity (e.g. vagal stimulation).^[4]

Non-dihydropyridine calcium channel blockers such as verapamil block the slow inward calcium current in cardiac tissues, thereby having a negatively dromotropic, chronotropic and inotropic effect.^[5] This (and other) pharmacological effect makes these drugs useful in the treatment of angina pectoris. Conversely, they can lead to symptomatic disturbances in cardiac conduction and bradyarrhythmias, and may aggravate left ventricular failure.^[6]

See also

• Bathmotropic
• Inotrope
• Catecholamines

Notes and References

1. Web site: "AV node; the magnitude of the delay" - Google Search. www.Google.ca. 14 April 2019.
2. Furukawa. Y.. Wallick, D. W. . Martin, P. J. . Levy, M. N. . Chronotropic and dromotropic responses to stimulation of intracardiac sympathetic nerves to sinoatrial or atrioventricular nodal region in anesthetized dogs. Circulation Research. 1 May 1990. 66. 5. 1391–1399. 10.1161/01.RES.66.5.1391. 2335032. free.
3. http://www.emedicinehealth.com/script/main/srchcont_dict.asp?src=Dromotropic Dromotropic
4. Web site: Toronto Notes for Medical Students Essential Med Notes 2016. Shafinewaz. RPh. 14 April 2019. www.Academia.edu.
5. Web site: eTG complete. HCN.net.au. 14 April 2019. https://web.archive.org/web/20070214101454/http://etg.hcn.net.au/. 14 February 2007. dead.
6. Web site: AccessMedicine - Harrison's Internal Medicine: Stable Angina Pectoris. https://web.archive.org/web/20070927003933/http://www.accessmedicine.com/content.aspx?aID=82370&searchStr=calcium+channel+blockers. dead. 27 September 2007. 27 September 2007. 14 April 2019.