Ventricular fibrillation, often referred to as VFib, V–fib, or VF, is a form of irregular heart rhythm known as an arrhythmia. This condition involves the rapid and uncoordinated contraction of the lower chambers of the heart, leading to an inadequate pumping of blood throughout the body. Ventricular fibrillation is a medical emergency that demands immediate attention and is the leading cause of sudden cardiac death.
During ventricular fibrillation, the lower heart chambers quiver or twitch instead of contracting and expanding properly, which disrupts the normal blood–pumping function.
Emergency treatment for ventricular fibrillation typically involves cardiopulmonary resuscitation (CPR) and the application of electrical shocks to the heart using a device called an automated external defibrillator (AED). In some cases, healthcare professionals may recommend medications, implanted medical devices, or surgical procedures to prevent future episodes of ventricular fibrillation.
The most common symptoms of ventricular fibrillation are collapse and a loss of consciousness. Prior to experiencing a ventricular fibrillation episode, individuals may exhibit signs of an irregularly fast or erratic heartbeat, known as arrhythmia, which can include:
If you are experiencing an unexplained fast or pounding heartbeat, it is advisable to schedule an appointment with a cardiologist.
In the event you witness someone collapsing due to a potential cardiac emergency, it is crucial to seek immediate medical assistance by following these steps:
Ventricular fibrillation can be caused by several factors:
The heart comprises four chambers: two upper atria and two lower ventricles. Within the right atrium, the sinus node serves as the heart’s natural pacemaker, initiating each heartbeat. Electrical signals from the sinus node traverse the atria, causing them to contract and pump blood into the ventricles. These signals then reach the atrioventricular (AV) node, slowing down briefly to allow the ventricles to fill with blood. Once they reach the ventricles, the lower chambers contract, propelling blood to the lungs or the rest of the body. In a healthy heart, this process results in a resting heart rate of 60 to 100 beats per minute. However, in ventricular fibrillation, rapid and irregular electrical signals cause the ventricles to quiver ineffectively rather than pump blood.
Factors that may increase the risk of experiencing ventricular fibrillation include: