Purkinje fibers

Jump to navigation Jump to search

Template:Infobox Anatomy

WikiDoc Resources for Purkinje fibers

Articles

Most recent articles on Purkinje fibers

Most cited articles on Purkinje fibers

Review articles on Purkinje fibers

Articles on Purkinje fibers in N Eng J Med, Lancet, BMJ

Media

Powerpoint slides on Purkinje fibers

Images of Purkinje fibers

Photos of Purkinje fibers

Podcasts & MP3s on Purkinje fibers

Videos on Purkinje fibers

Evidence Based Medicine

Cochrane Collaboration on Purkinje fibers

Bandolier on Purkinje fibers

TRIP on Purkinje fibers

Clinical Trials

Ongoing Trials on Purkinje fibers at Clinical Trials.gov

Trial results on Purkinje fibers

Clinical Trials on Purkinje fibers at Google

Guidelines / Policies / Govt

US National Guidelines Clearinghouse on Purkinje fibers

NICE Guidance on Purkinje fibers

NHS PRODIGY Guidance

FDA on Purkinje fibers

CDC on Purkinje fibers

Books

Books on Purkinje fibers

News

Purkinje fibers in the news

Be alerted to news on Purkinje fibers

News trends on Purkinje fibers

Commentary

Blogs on Purkinje fibers

Definitions

Definitions of Purkinje fibers

Patient Resources / Community

Patient resources on Purkinje fibers

Discussion groups on Purkinje fibers

Patient Handouts on Purkinje fibers

Directions to Hospitals Treating Purkinje fibers

Risk calculators and risk factors for Purkinje fibers

Healthcare Provider Resources

Symptoms of Purkinje fibers

Causes & Risk Factors for Purkinje fibers

Diagnostic studies for Purkinje fibers

Treatment of Purkinje fibers

Continuing Medical Education (CME)

CME Programs on Purkinje fibers

International

Purkinje fibers en Espanol

Purkinje fibers en Francais

Business

Purkinje fibers in the Marketplace

Patents on Purkinje fibers

Experimental / Informatics

List of terms related to Purkinje fibers

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Overview

Purkinje fibers (or Purkyne tissue) are located in the inner ventricular walls of the heart, just beneath the endocardium. These fibers are specialized myocardial fibers that conduct an electrical stimulus or impulse that enables the heart to contract in a coordinated fashion.

Histology

Because of their specializations to rapidly conduct impulses (numerous sodium ion channels and mitochondria, fewer myofibrils than the surrounding muscle tissue), Purkinje fibers take up stain differently than the surrounding muscles cells, and on a slide, they often appear lighter and larger than their neighbors.

The larger round cells on the right are purkinje fibers.

Function

Purkinje fibers work with the sinoatrial node (SA node) and the atrioventricular node (AV node) to control the heart rate.

During the ventricular contraction portion of the cardiac cycle, the Purkinje fibers carry the contraction impulse from the left and right bundle branches to the myocardium of the ventricles. This causes the muscle tissue of the ventricles to contract and force blood out of the heart — either to the pulmonary circulation (from the right ventricle) or to the systemic circulation (from the left ventricle).

The impulse through the Purkinje fibers is associated with the QRS complex.

Purkinje fibers also have the ability of automaticity - they generate action potentials, but at a slower rate than sinoatrial node and other atrial ectopic pacemakers. Thus they serve as the last resort when other pacemakers fail.

Historical Perspective

They were discovered in 1839 by Jan Evangelista Purkinje, who gave them his name.

See also


Template:WikiDoc Sources