atrial septum

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Related to atrial septum: interatrial septum, Ventricular septum


 [sep´tum] (L.)
1. a wall or partition dividing a body space or cavity. Some are membranous, some are osseous, and some are cartilaginous; each is named according to its location. See also septal defect. adj., adj sep´tal.
alveolar septum interalveolar septum.
atrial septum (septum atrio´rum cor´dis) interatrial septum.
atrioventricular septum the part of the membranous portion of the interventricular septum between the left ventricle and the right atrium.
deviated septum an injury or malformation of the nasal septum so that one part of the nasal cavity is smaller than the other; this is fairly common and seldom causes complications. Occasionally the deviation may handicap breathing, block the normal flow of mucus from the sinuses during a cold, or prevent proper drainage of infected sinuses. In some cases surgery (called partial or complete submucous resection) may be necessary to relieve the obstruction and reduce irritation and infection in the nose and sinuses.
interalveolar septum
1. one of the thin plates of bone separating the alveoli of the teeth in the mandible and maxilla. Called also interradicular septum.
2. one of the thin septa that separate adjacent pulmonary alveoli, containing connective tissue and the capillary network of the blood supply of the lung. Defs. 1 and 2 called also alveolar septum.
interatrial septum (septum interatria´le cor´dis) the partition separating the right and left atria of the heart; called also atrial septum.
interradicular septum interalveolar septum (def. 1).
interventricular septum (septum interventricula´re cor´dis) the partition separating the right and left ventricles of the heart; called also ventricular septum.
nasal septum a plate of bone and cartilage covered with mucous membrane that divides the nasal cavity.
septum lu´cidum septum pellucidum.
pellucid septum (septum pellu´cidum) the triangular double membrane separating the anterior horns of the lateral ventricles of the brain; called also septum lucidum.
septum pri´mum a septum in the embryonic heart, dividing the primitive atrium into right and left chambers. See also congenital heart defect.
rectovaginal septum the membranous partition between the rectum and vagina.
rectovesical septum a membranous partition separating the rectum from the prostate and urinary bladder.
septum of ventricles of heart (ventricular septum) (septum ventriculo´rum cor´dis) interventricular septum.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.


(sep'tum) plural.septa [L. saeptum, a partition]
A wall dividing two cavities. septal (-tal), adjective

atrial septum

Interatrial septum

septum atriorum cordis

Interatrial septum.

atrioventricular septum

The septum that separates the right and left atria of the heart from the respective ventricles.

crural septum

Femoral septum.

deviated septum

A nasal septum displaced to one side. It sometimes causes impaired air flow through a nostril.

femoral septum

Connective tissue that closes the femoral ring. Synonym: crural septum

interatrial septum

The myocardial wall between the atria of the heart.

interdental septum

The bony partition across the alveolar process between adjacent teeth that forms part of the tooth sockets.

intermuscular septum

1. A connective tissue septum that separates two muscles, esp. one from which muscles may take their origin.
2. One of two connective tissue septa that separate the muscles of the leg into anterior, posterior, and lateral groups.

interradicular septum

One of the thin bony partitions between the roots of a multirooted tooth that forms part of the walls of the tooth socket.

interventricular septum

The myocardial wall between the ventricles of the heart.

lingual septum

A sheet of connective tissue underlying the midline groove (median sulcus) separating the halves of the tongue.

mediastinal septum

A partition between two parts of an organ or cavity.

nasal septum

The partition that divides the nasal cavity into two nasal fossae. The bony portion is formed by the perpendicular plate of the ethmoid bone and the vomer. The cartilaginous portion is formed by septal and vomeronasal cartilages and medial crura of greater alar cartilages. Both sides of the septum are covered with mucous membranes.

orbital septum

A fibrous sheet extending partially across the anterior opening of the orbit within the eyelids.

septum pectiniforme

Comblike partition that separates the corpora cavernosa.

septum pellucidum

A thin, translucent, triangular sheet of nervous tissue consisting of two laminae attached to the corpus callosum above and the fornix below. It forms the medial wall and interior boundary of the lateral ventricles of the brain Synonym:

septum primum

In the embryonic heart, a septum between the right and left chambers.

rectovaginal septum

The layer of fascia between the rectum and the vagina.

rectovesical septum

The membranous septum between the rectum and the urinary bladder.

septum scroti

The partition dividing the left and right sides of the scrotum.

tracheoesophageal septum

In the embryo, the partition that develops between the growing laryngotracheal tube (the future larynx, trachea, and lungs) and the developing esophagus.

ventricular septum

Interventricular septum.
Medical Dictionary, © 2009 Farlex and Partners
References in periodicals archive ?
Abbreviations LHAS: Lipomatous hypertrophy of the atrial septum TEE: Transesophageal echocardiography TTE: Transthoracic echocardiography LAD: Left anterior descending artery RCX: Ramus circumflex RCA: Right coronary artery RA: Right atrium.
A separate issue is that mild heart defects, especially of the atrial septum, can be overdetected, particularly for infants born preterm who are under increased surveillance and whose hearts have yet to fully mature (Tanner et al.
However, with Ach (i.e., [Ach] = 0.03 [micro]M/L), the mutation significantly increased the CL (Figure 4(c)) and produced a conduction block in the direction toward the atrial septum; the action potential conduction in the direction toward the CT was sustained.
"It's also a big deal engineering-wise, because you have to fold the valve and then guide it through the atrial septum. Then you open it up." The atrial septum is the wall separating the heart's upper two chambers, the atria.
(1) Myxomas most commonly occur in the left atrium (90%) and are generally attached to the atrial septum in or adjacent to the fossa ovalis.
The atrial septum is the wall between the left and right atria (upper chambers) of the heart.
MVP is characterized by accumulation of mucinous material in valve leaflets, membranous and atrial septum, and mitral and tricuspid valve rings.
To the Editor.--We read the outstanding article by Miller and Tazelaar1 recently published in the Archives of Pathology & Laboratory Medicine about the main features of 5 cardiovascular pseudoneoplasms (inflammatory myofibroblastic tumor, hamartoma of mature cardiac myocytes, mesothelial monocytic cardiac excrescences, calcified amorphous tumor, and lipomatous hypertrophy of the atrial septum).
When the atrial septum remains open, pulmonary venous blood that enters the left atrium flows into the right atrium, producing a left-to-right shunt.
These are the criteria according to which the patient is suitable for percutanous closure of ASD using the Amplatzer ASD closure device: central defect; the defect with a modest deficit of one edge to 1-2 mm (aortic and inferior); an aneurysm of atrial septum with fenestration or central single defect; patients' age is older than three years.
Kalvaitis and his associates performed DE MRI exams on 62 patients with atrial fibrillation scheduled to undergo pulmonary vein antrum isolation and atrial septum de-bulking.
vignai in having closely arising and extended epigynal teeth, posteriorly situated atrium, and broad, round spermathecae but can be distinguished by the absence of atrial septum, anteriorly extended posterior atrial margin, and slightly separated spermathecae (Figs.