sinus node


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Related to sinus node: Sinus Node Dysfunction

sin·u·a·tri·al node

[TA]
the mass of specialized cardiac muscle fibers that normally acts as the "pacemaker" of the cardiac conduction system; it lies under the epicardium at the upper end of the sulcus terminalis.
Synonym(s): nodus sinuatrialis [TA], atrionector, Flack node, Keith and Flack node, Keith node, Koch node, sinoatrial node, sinus node
Farlex Partner Medical Dictionary © Farlex 2012

sinus node

n.
See sinoatrial node.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.

sinus node

Sinoatrial node, see there, SA node.
McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.

node

(nod) [L. nodus, knot]
1. A knot, knob, protuberance, or swelling.
2. A constricted region.
3. A small rounded organ or structure.

Aschoff node

Atrioventricular node.

atrioventricular node

Abbreviation: AV node
A node of specialized cardiac muscle fibers in the lower interatrial septum that receives impulses from the sinoatrial node and transmits them to the bundle of His.
Synonym: Aschoff node See: atrioventricular bundle; conduction system of the heart for illus

Bouchard node

In osteoarthritis, bony enlargement of the proximal interphalangeal joints.

ectopic lymph node

A cluster of immunologically active cells inside a malignant tumor. The node may represent an attempt by the body to destroy foreign antigens on the tumor cell surface.

Haygarth nodes

Joint swelling seen in rheumatoid arthritis.

Heberden nodes

See: Heberden nodes

hemal node

A vascular node that structurally resembles a lymph node, present in certain ungulates. Synonym: hemal gland

Hensen node

See: Hensen, Christian Andreas Victor
Enlarge picture
LYMPH NODE

lymph node

A small encapsulated lymphoid organ that filters lymph. Lymph nodes are found at junctions or branches along the lymphatics. They provide sites where immune responses can be generated through the interaction of antigens, macrophages, dendritic cells and lymphocytes. See: illustration; immune response; inflammation; lymph; lymphocyteLymph nodes are 0.1-2.5 cm long kidney-shaped aggregates of lymphocytes and macrophages embedded in a meshwork reticulum composed of thin collagen fibers. At each lymph node, an artery enters through a surface indentation (the hilum) alongside an exiting vein and an exiting (efferent) lymphatic vessel; a number of afferent lymphatic vessels enter the lymph node at other sites. Inside lymph nodes, lymph slowly flows through endothelial sinuses lined by lymphocytes and macrophages. Macrophages remove macromolecules, particles, debris, and microorganisms from the lymph stream. Lymphocytes and antibodies move through the walls of the sinuses and into the passing lymph, while dendritic cells pass from the lymph into the lymphatic follicles, carrying antigens from the body's epithelia and from infected tissues. In the cortical region of the lymph node, the sinuses wind around lymphatic follicles, which are ovoid germinal centers packed with differentiating and proliferating B lymphocytes and surrounded by loose T lymphocytes. Lymphocytes and antibodies also enter and exit blood capillaries throughout the lymph node. Lymph nodes are most numerous in the neck, mediastinum, abdominal mesenteries, pelvis, the proximal limbs (the axillae and the groin), and along the posterior abdominal wall. Inside the chest and trunk, lymph nodes tend to be found along the veins near viscera.

Meynet nodes

See: Meynet nodes

neurofibril node

Ranvier's node.

Osler nodes

See: Osler nodes

Parrot nodes

See: Parrot nodes

piedric node

A node on the hair shaft seen in piedra.

primitive node

A knoblike structure at the anterior end of the primitive streak.
Synonym: Hensen knot; primitive knot

Ranvier node

See: Ranvier node

Schmorl node

A node seen in radiographs of the spine. It is caused by prolapse of the nucleus pulposus into the end plate of the vertebra.

sentinel node

1. A lymph node that receives drainage from a tumor and is likely to harbor metastatic disease before cancer cells have the opportunity to spread elsewhere.
2. Signal node.

signal node

Enlargement of one of the supraclavicular lymph nodes; usually indicative of primary carcinoma of thoracic or abdominal organs. Synonym: sentinel node (2); Troisier's node; Virchow node

singer's node

Noncancerous, callus-like growths on the inner parts of the vocal cords, usually caused by voice abuse or overuse. It is marked by a singer's hoarseness and an inability to produce the desired notes. It is treated by resting the voice. Surgical removal of the nodules is necessary if they do not respond to conservative therapy. Synonym: chorditis nodosa; laryngeal nodule

sinoatrial node

Abbreviation: SA node
A specialized group of cardiac muscle cells in the wall of the right atrium at the entrance of the superior vena cava. These cells depolarize spontaneously and rhythmically to initiate normal heartbeats.
Synonym: pacemaker (2); sinus node

sinus node

Sinoatrial node.

syphilitic node

Circumscribed swelling at the end of long bones due to congenital syphilis. The nodes are sensitive and painful during inflammation, esp. at night.
See: Parrot's nodes

Troisier's node

Signal node.

Virchow node

Signal node.
Medical Dictionary, © 2009 Farlex and Partners
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References in periodicals archive ?
The importance of the sinus node artery in blood supply of the atrial myocardium.
A study on anatomy and variations of sinoatrial nodal artery
We managed to avoid sinus node injury by carefully confining the incision at the SVC and right atrial interface to posterior and lateral area.
Outcome after surgical repair of partial anomalous pulmonary venous connection
The researchers say these molecular changes in the sinus node - the cardiac structure responsible for generating heart rhythm - may help us to understand the more frequent occurrence of heart rhythm disturbances or even loss of consciousness in athletes.
Why athletes likelier to need pacemakers during old age
Sick sinus syndrome (SSS) comprises a variety of conditions involving sinus node dysfunction (SND) which occurs as a result of anatomical damage to the sinoatrial node (SAN) of the heart.
Isoprenaline: a potential contributor in sick sinus syndrome--insights from a mathematical model of the rabbit sinoatrial node
Some patients with sinus node disease are unable to appropriately increase their heart rate with exercise.
Chinese medicine Shensongyangxin is effective for patients with bradycardia: results of a randomized, double-blind, placebo-controlled multicenter trial
Fistula from proximal CX was originating from small side branch and fistula from proximal RCA was originating after sinus node artery and terminating in the lung parenchyma as two tracts (Fig.
Multilateral coronary fistulas terminating in the lung parenchyma/ Akciger parenkiminde sonlan an multilateral kor oner fistuller
Most of these medications slow the heart rate, either by calming the sinus node, the body's natural pacemaker, or by slowing down the electrical activity in the heart.
WHEN YOUR HEART SKIPS A BEAT OR TWO
Heart rate variability (HRV) refers to the beat-to-beat variation in heart rate generated by the interplay of sympathetic and parasympathetic nerve activity at the sinus node of the heart.
Gender differences of heart rate variability in healthy volunteers
Sinus node tachycardia (FIGURE 1), the most common arrhythmia, (1) is an appropriate response to physiologic or emotional stress or disease processes.
Targeting tachycardia: diagnostic tips and tools: many narrow QRS complex tachycardias are benign, but some require rapid intervention. The review, EKG strips, and algorithm you'll find here will help you get to the source of the problem without delay
"Normally, the heartbeat comes from the sinus node of the heart (putting you in 'sinus rhythm')," she explains.
Treat atrial fibrillation to reduce your stroke risk: medication is the first line of defense, but other treatments or procedures also are effective
They provide a step-by-step approach for bradycardias, tachycardias, sinus node function, heart block, normal and abnormal pacemaker and implantable defibrillator function, and related topics like syncope, arrhythmias in the athlete, palpitations, and other conditions.
Arrhythmias essentials

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