The question is that what is a fibrillation? A Fibrillation this term is used in the cardiac arrhythmia. First what is fibrillation means; it means uncoordinated contraction of muscles. In heart we say uncoordinated contraction of heart muscles.
Now how this fibrillation occurs in the heart and heart is the vital organ of whole body, if any disturbance in the heart occurs it may straight away lead to death. Heart has four chambers right and left atria's and right and left ventricles. Fibrillation may occur in both the atria or in both the ventricles due to the disturbance in the traveling of electrical impulses to these sides.
One is the ATRIAL fibrillation occur in the atria of heart, in that condition the atria cannot contract properly or it is the rapid, irregular ATRIAL rhythm. Symptoms include: Palpitation, Chest discomfort.
Patients may also have the signs of acute stroke or damage to organ due to systemic embolism etc. The most common causes are:
Hypertension, mitral or tricuspid VALVULAR disorders, hyperthyroidism. Less common causes are: PULMONARY EMBOLISM, MYOCARDITIS, PERICARDITIS.
A FREQUENT CAUSE OF ATRIAL FIBRILLATION IS ATRIAL ENLARGEMENT resulting from the heart valve lesion that prevents the atria to emptying into the ventricles. The dilated atria provide ideal condition of long conductive pathway as well a slow conduction.
Treatment is done by: Rate control with drugs. Prevention of THROMBOEMBOLISM with anticoagulant
Sometimes conversion to sinus rhythm by using drugs
In fibrillation of atria, atria become useless as a primer pump for ventricles even so blood flows passively through atria into the ventricle and efficiency of ventricular pumping is decreased 20 to 30 percent
Second, the most serious of all cardiac arrhythmia is ventricular fibrillation, which is not stopped within 1 to 3 minutes ALMOST fatal.
Ventricular fibrillation results from the cardiac impulses that have gone within the ventricular muscles stimulating first one portion of ventricles, then the other portion and then next. Eventually feeling to re excite the same muscle over and over-never stopping.
Thus there is never coordinated contraction of all ventricles muscles at once, requires for cardiac cycle- despite massive movements of stimulatory signals- throughout the ventricles, ventricles chamber neither enlarge nor contract but remain in intermediate stage of partial contraction, pumping either no/negligible amount of blood.
Causes are: Sudden electric shock of heart, ISCHEMIA of heart muscles. Circus movements of impulses within the ventricles
Treatment is done by: Defibrillation (Hand pumping of heart)
This is the whole description of the a fibrillation.