What is the difference between atrial fibrillation and ventricular tachycardia

VFib is a medical emergency that will lead to death if not treated promptly. The heart is one large organ comprised of four chambers. Though they have similar names and both occur in the heart, AFib and VFib affect the body in different ways.

Learn more in the following sections about how each condition affects the heart. In a healthy heart, blood is pumped from the upper chamber into the lower chamber or from the atria into the ventricles in a single heartbeat. During that same beat, the blood is pumped from the ventricles into the body. However, when AFib affects a heart, the upper chambers no longer pump the blood into the lower chambers and it has to flow passively.

With AFib, blood in the atria may not completely empty. AFib is typically not life-threatening. The most serious complications are stroke , heart attack , and blockage of blood vessels leading to organs or limbs. Learn more: Stroke symptoms ». The ventricles, in turn, do not contract and pump blood out of the heart into the body. VFib is an emergency situation. If you develop VFib, your body will not receive the blood it needs because your heart is no longer pumping.

Untreated VFib results in sudden death. Thallium, or some other radioactive material, is injected into the bloodstream.

Special cameras detect the radioactive material as it flows through the lungs and heart. This test can detect where areas of reduced blood flow to the muscles are.

This is a type of ultrasound test that utilizes high-pitched sound waves sent through a transducer, a wand-like device that is held on the chest. The transducer picks up echoes of the sound waves as they bounce off different parts of the heart. The data appears on a video screen, where the doctor can see the heart as it moves. This test can help a doctor identify underlying structural heart disease. The catheter usually enters the body at the groin or arm.

A dye is injected through the catheter into the arteries. This dye stands out on images created by an X-ray and helps doctors detect coronary artery disease.

Coronary artery disease happens when arteries to the heart have narrowed. These imaging tests can measure ejection fraction as well as the heart arteries and valves.

They can also determine whether the patient had a heart attack and detect unusual causes of heart failure. If a physician determines that the ventricular fibrillation results from scar tissue due to a heart attack, or some structural defect in the heart, medications and medical procedures may be recommended to minimize the risk of VFib happening again.

The following may be recommended:. Beta blockers are commonly used to prevent sudden cardiac arrest or ventricular fibrillation. Examples include metoprolol, propranolol, timolol, and atenolol. Angiotensin-converting enzyme ACE inhibitors ease the workload of the heart by opening up blood vessels and lowering blood pressure. They may also protect the heart from further damage. A blood test will be necessary to make sure the kidneys are working properly before starting on this type of medication.

About 10 days after starting treatment, there will be further tests to make sure the kidneys are still working properly. Over a period of about 3 weeks, the dose gradually increases. Examples of ACE inhibitors include lisinopril, perindopril and ramipril. Amiodarone Cordarone or calcium channel blockers may also be prescribed. This device is placed inside the body. It is designed to recognize certain types of arrhythmias, or abnormal heart rhythms, and correct them by emitting electric shocks to reset the heart to a normal rhythm.

Angioplasty opens up the coronary artery. There is a small balloon, shaped like a sausage, at the end of the wire. The balloon is placed at the narrowest part of the artery and is then inflated, squashing the clot away. A flexible metal mesh, called a stent, is then placed there to keep that part of the artery open. The damaged blood vessel is by-passed with grafts taken from blood vessels elsewhere in the body.

This damage might be related to heart disease, aging, inherited or congenital defects, or it might be caused by certain medicines—including those used to control arrhythmias and high blood pressure. Tachycardia is a very fast heart rate of more than beats per minute. The many forms of tachycardia depend on where the fast heart rate begins. If it begins in the ventricles, it is called ventricular tachycardia. If it begins above the ventricles, it is called supraventricular tachycardia. Ventricular tachycardia is a condition in which the SA node no longer controls the beating of the ventricles.

Instead, other areas along the lower electrical pathway take over the pacemaking role. Since the new signal does not move through your heart muscle along the regular route, the heart muscle does not beat normally. The most serious arrhythmia is ventricular fibrillation, which is an uncontrolled, irregular beat.

Instead of one misplaced beat from the ventricles, you may have several impulses that begin at the same time from different locations—all telling the heart to beat. The result is a much faster, chaotic heartbeat that sometimes reaches beats a minute. This chaotic heartbeat means very little blood is pumped from the heart to the brain and body and can result in fainting. Medical attention is needed right away. About , deaths from heart attacks each year are thought to be caused by ventricular fibrillation.

People who have heart disease or a history of heart attack have the highest risk of ventricular fibrillation. A less serious type of ventricular arrhythmia is a premature ventricular contraction PVC. When anything disrupts this complex system, it can cause the heart to beat too fast tachycardia , too slow bradycardia or with an irregular rhythm.

Any condition that puts a strain on the heart or damages heart tissue can increase your risk of ventricular tachycardia. Lifestyle changes or medical treatment may decrease the risk associated with the following factors:. If you have a family history of ventricular tachycardia or other heart rhythm disorders, you may have an increased risk of ventricular tachycardia.

Complications of ventricular tachycardia vary in severity and depend on how fast your heart is beating, how long the rapid heartbeat lasts, how often tachycardia occurs and your overall heart health. Possible complications include:. A dangerous condition related to ventricular tachycardia is ventricular fibrillation V-fib. In V-fib , your lower heart chambers contract in a very rapid and uncoordinated manner. This abnormal rhythm happens most often in people with heart disease or a prior heart attack.

It may also occur due to electrolyte problems such as high or low potassium levels or, rarely, in otherwise normal hearts. Ventricular fibrillation may also cause sudden cardiac arrest and lead to death if not treated immediately. The best way to prevent ventricular tachycardia is to treat or eliminate risk factors that may lead to heart disease. If you already have heart disease, follow your treatment plan and a heart-healthy lifestyle.

Ventricular tachycardia care at Mayo Clinic. Mayo Clinic does not endorse companies or products. Advertising revenue supports our not-for-profit mission. This content does not have an English version. This content does not have an Arabic version. Overview Ventricular tachycardia heartbeat Open pop-up dialog box Close. Ventricular tachycardia heartbeat In ventricular tachycardia, an abnormal electrical impulse originating in the lower chambers of the heart ventricles causes the heart to beat faster.

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