Sinus rhythm

Sinus rhythm

Sinus rhythm is a term used in medicine to describe the normal beating of the heart, as measured by an electrocardiogram (ECG). It has certain generic features that serve as hallmarks for comparison with normal ECGs.

ECG Structure

There are typically five distinct waves (identified by the letters P, Q, R, S, and T) in a single beat of the heart in sinus rhythm, and they occur in a specific order, over specific periods of time, with specific relative sizes. While there is a significant range within which variations in rhythm are considered normal, anything that deviates from sinus rhythm by more than a certain amount may be indicative of heart disease.

inus Rhythm on ECG

Sinus rhythm is characterized by a usual rate of anywhere between 60-100 bpm. Every QRS complex is preceded by a P wave and every P wave must be followed by a QRS (the opposite occurs if there is second or third degree AV block). The P wave morphology and axis must be normal and the PR interval will usually be 120 ms to 200 ms. In normal sinus rhythm, electrical impulses from the SA node travel to the AV node with successful contraction of the two atria. The electrical impulses from the AV node successfully contract the ventricles. On the ECG, there are normal PQRST elements with no evidence of arrhythmia,

External links

* [http://pediatriccardiology.uchicago.edu/PP/abnl%20rhythm%20for%20parents%20body.htm Normal Sinus Rhythm]


Wikimedia Foundation. 2010.

Игры ⚽ Поможем сделать НИР

Look at other dictionaries:

  • Sinus rhythm — The normal regular rhythm of the heart set by the natural pacemaker of the heart called the sinoatrial (or sinus) node. It is located in the wall of the right atrium (the right upper chamber of the heart). Normal cardiac impulses start there and… …   Medical dictionary

  • sinus rhythm — noun Date: 1911 the rhythm of the heart produced by impulses from the sinus node < restored the patient to normal sinus rhythm > …   New Collegiate Dictionary

  • sinus rhythm — a normal heart rhythm, usually as recorded on an electrocardiogram. The sinoatrial node, located in the right atrium, normally functions as the natural pacemaker for the heart …   The new mediacal dictionary

  • Sinus — may refer to:In anatomy, where a sinus is a sac or cavity in any organ or tissue: *Sinus (anatomy), description of the general term *Anal sinuses, the furrows which separate the columns in the rectum *Paranasal sinuses, air cavities in the… …   Wikipedia

  • Rhythm, sinus — The normal regular rhythm of the heart set by the natural pacemaker of the heart called the sinoatrial (or sinus) node. It is located in the wall of the right atrium (the right upper chamber of the heart). Normal cardiac impulses start there and… …   Medical dictionary

  • Sinus tachycardia — A fast heartbeat (tachycardia) because of rapid firing of the sinoatrial (sinus) node. The sinoatrial (or sinus) node is the natural pacemaker of the heart. It is located in the wall of the right atrium (the right upper chamber of the heart).… …   Medical dictionary

  • Sinus bradycardia — A regular but unusually slow heart beat (60 beats/minute or less at rest). Sinus bradycardia can be the result of many things including good physical fitness, medications, and some forms of heart block. Sinus refers to the sinus node, the heart s …   Medical dictionary

  • Sinus arrhythmia — The normal increase in heart rate that occurs during inspiration (when you breathe in). This is a natural response and is more accentuated in children than adults. The sinus refers to the natural pacemaker of the heart which is called the… …   Medical dictionary

  • sinus arrest — a halt, usually transient, in the normal cardiac (sinus) rhythm due to a slowing or cessation of impulse initiation by the sinus node, lasting for an interval that is not an exact multiple of the normal cardiac cycle; either ectopic pacemakers… …   Medical dictionary

  • sinus pause — a transient interruption in the sinus rhythm, of a duration that is not an exact multiple of the normal cardiac cycle. See also sinus arrest, under arrest …   Medical dictionary

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”