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Related to fibrillation: ventricular fibrillation


1. a local and uncontrollable twitching of muscle fibres, esp of the heart, not affecting the entire muscle. Atrial fibrillation results in rapid and irregular heart and pulse rate. In ventricular fibrillation, the heart stops beating
2. irregular twitchings of the muscular wall of the heart, often interfering with the normal rhythmic contractions
Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



the destruction by mechanical action of the bonds between the tiny fibers (fibrils and microfibrils) making up the cell walls of plant fibers and the penetration by water of the space between the fibrils.

Fibrillation may occur both on the surface of and within the cell wall of the fibers. With surficial fibrillation fragments of fibrils and the cell wall are separated from the fibers and form a nap on the fibers. With internal fibrillation the weakening and partial destruction of the bonds between fibrils increase the flexibility and plasticity of the fibers. Internal fibrillation enables the fibers to form bonds without losing strength. Fibrillation, the main process in beating cellulose during paper production, increases the surface of the fibers and releases the hemicelluloses inside the fibers, making it possible for the hemicelluloses to take part in the formation of bonds between fibers in the sheet of paper. The splitting of the fibrils establishes conditions for improved intertwining of fibers, increasing the mechanical strength of the paper sheet yet reducing the absorbency. Rolls, conical and disk mills, and similar devices are used for fibrillation.


Ivanov, S. N. Tekhnologiia bumagi, 2nd ed. Moscow, 1970.


The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.


An independent, spontaneous, local twitching of muscle fibers.
A process in which yarn is extruded as a ribbon or a tape rather than as a fine filament.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
References in periodicals archive ?
In a large zoledronic acid study, the rate of serious atrial fibrillation was significantly higher in treated patients.
In the Fracture Intervention Trial (FIT) of alendronate for patients who have osteoporosis, the risk of serious atrial fibrillation was higher in alendronate recipients (1.5%, n=47) than in nonusers (1.0%, n=31).
During follow-up, the rate of new atrial fibrillation was 23% among patients not taking an omega-3 fatty acid, and 9% among those on an omega-3 fatty acid, said Dr.
After multivariable adjustment, the intervention reduced total unplanned hospitalisations by 26 per cent, atrial fibrillation related hospitalisations by 31 per cent, and other cardiovascular hospitalisations by 49 per cent, while having no impact on non-cardiac hospitalisations.
Patients who underwent elective valvular replacement, had rheumatic heart disease in combination with continuous atrial fibrillation, had no other types of arhythmia, had cardiac function no higher than grade III,9 satisfied the application indication of amiodarone, had normal level of electrolyte and acidity and alkalinity, and had heart rate lower than 70 times/min were included.
The researchers found that in the testing data set, 8.4 percent of patients had verified atrial fibrillation before the normal sinus rhythm ECG tested by the model.
The campaign aimed to raise public awareness about atrial fibrillation, the most common form of arrhythmia.
After adjustment for age and sex, individuals who had migraine with visual aura showed a significant 39% increase in the risk of incident atrial fibrillation, compared with those who experienced migraine without aura, and a 30% increased risk when compared with individuals who did not experience headache (P = .004).
ISLAMABAD -- Patients who take medication to treat hypothyroidism, being treated with too much medication can lead to an increased risk of atrial fibrillation, a common heart rhythm disorder associated with stroke,said a study.
The study shows that people with a particular kind of irregular heartbeat called atrial fibrillation may experience a faster decline in thinking and memory skills, and have a greater risk of dementia than those without the condition.
Objective: To find out the frequency of atrial fibrillation in patients with acute ischemic stroke presenting to a tertiary care hospital.