What is Ventricular fibrillation?
Ventricular fibrillation is a serious heart condition that causes abnormal heart rhythms. It can be fatal. For many people with this disorder, irregular heart rhythms are the first and only sign of coronary artery disease.
Ventricular fibrillation (VFib) can be confused with atrial fibrillation (AFib). Both involve irregular heart rhythms but affect different parts of the heart.
Atrial fibrillation can also indicate a serious heart condition, but it is usually a symptom of a chronic problem, not a life-threatening feature in and of itself.
VF; Fibrillation – ventricular; Arrhythmia – VF; Abnormal heart rhythm – VF; Cardiac arrest – VF; Defibrillator – VF; Cardioversion – VF; Defibrillate – VF.
Causes of ventricular fibrillation
Ventricular fibrillation can have several root causes, including:
- Insufficient blood flow to the heart muscle
- Damage to the heart muscle (from a heart attack, for sample)
- Problems with the aorta
- Drug toxicity
- Sepsis (severe body infection)
Symptoms of ventricular fibrillation
When VF occurs, the two chambers at the bottom of your heart cannot pump with enough force to move blood through your body. These lower chambers are called ventricles. This causes your blood pressure to drop quickly and prevents blood from circulating through your body. As a result, the blood cannot reach your vital organs.
Fainting or loss of consciousness are the most common symptoms of VF; early symptoms include:
- Chest pain
- Fast, fluttering heartbeat
- Difficulty breathing
These first symptoms may occur an hour or less before fainting or unconsciousness occurs.
Risk factors for ventricular fibrillation
The most common risk factors are:
- A weakened heart muscle (cardiomyopathy)
- A previous or acute heart attack
- Genetic diseases such as extensive or short QT syndrome, Brugada disease, or hypertrophic cardiomyopathy
- Certain medications that affect heart function
- Electrolyte abnormalities
Diagnosis of ventricular fibrillation
To diagnose V-fib, your healthcare provider will consider:
- Your vital marks, such as blood pressure and pulse
- Heart function tests, such as an EKG
- Your medical and general health history
- An explanation of your symptoms that you, a loved one, or a bystander provide
- A physical exam
Treatment for ventricular fibrillation
- Cardiopulmonary resuscitation
- Prevent new episodes
Ventricular fibrillation should be treated as an extreme emergency. Cardiopulmonary resuscitation (CPR) should be started as quickly as possible. It should be followed by defibrillation (an electric shock to the chest), as soon as the defibrillator is available. Then, medicines used to treat abnormal heart rhythms may be given to help maintain a normal heart rhythm.
When ventricular fibrillation happens within hours after a heart attack in people who are not in shock and do not have heart disappointment, immediate cardioversion restores normal rhythm in 95% of people and the prognosis is good. Shock and heart failure propose severe damage to the ventricles. If the ventricles are severely damaged, even direct cardioversion has only a 30% success rate, and 70% of people who are resuscitated die without regaining normal function.
People who are successfully resuscitated from ventricular fibrillation and survive are at high risk for another episode. If ventricular fibrillation is caused by a rescindable disorder, that disorder is treated. Otherwise, most people have an implantable cardioverter-defibrillator (ICD) surgically implanted to correct the problem if it recurs. ICDs continuously monitor the heart rate and rhythm, automatically detect ventricular fibrillation, and deliver a shock to convert the arrhythmia to a normal rhythm. These people are also often given medications to prevent recurrences.
If you have a first-degree relative (parent, brother, or child) with an inherited heart condition (congenital heart disease), talk to your doctor about genetic screening. Early identification of an inherited heart problem can guide preventive care and reduce the risk of complications.
People who have survived VF may be in a coma or have long-term damage to the brain or other organs.