Internal defibrillators are small battery powered units that deliver an electrical impulse to someone who is experiencing sudden cardiac arrest due to ventricular defibrillation. Before you or your loved one has a defibrillator implanted, you should learn about the device and what it does. Learning about the unit, the procedure, and what you can expect afterward will help alleviate anxiety.

An internal defibrillator constantly monitors an individual’s heart rate for any abnormalities. If the heart rate exceeds a certain number, an electrical therapy is administered to correct this problem. Studies show that when a person is experiencing cardiac arrest, defibrillation in the first several minutes increases the chances of survival.

Most defibrillators today also monitor for other heart conditions as well as cardiac arrest. If the heart is beating too slowly, the defibrillator acts as a pacemaker. If the heart is beating too fast, the defibrillator may give the heart a short burst of extra beats, which often corrects the problem before defibrillation. If it does not work, than the defibrillator gives the higher shock commonly associated with this device.

In the beginning uses of this therapy, internal defibrillators were put into the body through a thoracotomy and the defibrillator patches were applied to the epicardium or the pericardium. Now, most of the internal defibrillators are implanted transvenously into the left pectoral region. This is a similar placement to a pacemaker.

New technology has made internal defibrillators smaller and more easily implanted. Most weigh around 70 grams and are less than 13 mm thick. You may be able to feel the box and the leads under your skin, but as the wound heals, you shouldn’t experience any discomfort from it.

Many people feel worried about going home after having the device implanted. You should ask your nurses and doctors about the device and what to expect if you have questions. Knowing as much as you can about what to expect will help you feel more comfortable with the device.

If the defibrillator gives your heart an electrical impulse, you will likely feel pain that lasts for a few seconds. Those near you may notice you move suddenly, but they are completely safe from the electric impulse.

If you feel as though your heart is beating too fast or you are feeling dizzy, sit or lie down on the ground. Contact your doctor as soon as possible so that you can have the device and your heart checked out. If you feel unwell after a shock or if the device is giving multiple shocks, call 9-1-1 for an ambulance as it will be necessary to determine what is happening.

Internal defibrillators have been shown to help individuals who are at high risk for sudden cardiac arrest. New technology is making the devices safer and more efficient. If you or someone you love is having one implanted, ask your doctor to explain the device, the procedure, and what you can expect after the surgery.

Getting information on defibrillators is very useful in this fast moving world, where threats of cardiac attacks have become really trivial. Defibrillator is the device used in treating the disturbing and uneven movement of the heartbeat normally caused by a heart attack or a variety of other serious illnesses. Therefore, a little information on defibrillator helps in averting heart problems.

How a Defibrillator Works

Gathering information on defibrillators is very simple thing. It uses direct current as to give unsynchronized countershocks to stop ventricular fibrillation. The produced countershocks converts uneven and disturbed heart rhythm in an organized even and affective ways. The system has been administered by pressing a small button on the defibrillator paddles placed at the chest wall. Putting on the pressure to the defibrillator paddles enforces lungs to bring out the air from the chest wall in order to bringing it closer in contact with the heart.

Types of Defibrillators

A defibrillator normalizes heart beat movements caused by a heart stroke or serious illnesses. Getting information on various kinds of defibrillators including Manual external defibrillator, Manual internal defibrillator, Automated external defibrillator (AED), Semi-automated external defibrillator, and Implantable Cardioverter-Defibrillator (ICD) can be helpful. A brief discription of each of them has been explained below.

Manual External Defibrillator

Manual External Defibrillator is a kind of defibrillator with an inbuilt electrocardiogram to detect the condition of the heart. On the basis of diagonis of the heart, clinicians decide the intensity of the voltages to be given to the patient. Normally, electric pressure has been given through the paddles on the chest of the patients. This kind of defibralitor is commonly used in hospitals or ambulances.

Manual Internal Defibrillator

Also used in normalizing the heart beats, Manual Internal Delibrillator is just like normal defilbrillator, where electric charge is usually pumped in by internal paddles in close or direct contact with the heart. Because of its intricate usage, these devices are mainly used in operating theatres, where the chest can be opened or being treated by a surgeon.

Automated External Defibrillator (AED)

Information on defbrillator has become a life-saving treatment for all heart patients. Automated External Defibrillator is used to identify the rhythm of the heart through a computer based setup. The system identifies the need for an electric shock or not. Aiming at the layman usage, the appratus has been designed in such a way so that a common man with little training can operate it. This kind of equipment is generally found in government offices, shopping centres and other public places.

Semi-Automated External Defibrillator

This device carries both the features of full-manuated as well as automated units of defibrillator. Equipped with the AED capabilities, this unit also has an ECG display and manual override in it. Due to its distinguish features, this device is generally used by paramedics and emergency medicine technicians.

Implantable Cardioverter-Defibrillator

As its name suggests, Implantable Cardioverter-Defbrillator is used as implants and helps in keeping a close watch on the patient’s heart beat rhythm and capable of administering the shocks automatically through its designed program.

Defibrillator has increasingly become an important medical device for people prone to cardiovascular diseases. Information on defibrillators is necessary not only for heart patients but for everyone else is interested in keeping his or her heart healthy and pounding happily.

Until quite recently, implanted defibrillators (or implanted cardioverter defibrillator, I.C.D.), were not widely known among the general public. Oh sure, lots of people knew about pacemakers; they’ve been around for years. But, the idea of a miniaturized defibrillator put inside a person’s body, that was the stuff of science fiction. However, ever since it was announced that Vice President Dick Cheney had one, public interest (and knowledge) has increased. And with good reason; the devices are credited with saving the lives of what medical science declares the sickest types of heart patients.

For many years, doctors were under the impression that patients suffering from heart disease died from a progressive failure of the organ. In lay terms, the heart just got tired and stopped pumping. In that kind of patient, an implanted defibrillator (I.C.D.) would not be a viable course of treatment. However, recent studies have found that the more usual cause of death was a sudden malfunction of the normal sinus rhythm of the heart. This situation is precisely what an I.C.D. is designed for. The device examines the electrical signals in the heart at regular intervals and watches for any signs of an irregular heartbeat. If detected, it acts within seconds to jolt the heart and return it a normal beat. As the mechanism is within the patient’s body, it can, if necessary, give a more potent shock than an external defibrillator. Also, often times the device will have some sort of telemetry component that will record the patient’s heart activity and download it to the doctor’s office, thus enabling him/her to monitor the patient’s progress.

Now, some people might say: "Whoa, wait, I’ve seen ‘E/R’, I know what those things do to a person. I don’t want to be lying in bed, watching TV and then – bam! I get jolted right out of bed when that thing zaps me." That is not the case. Since the shock is delivered directly to the heart, the physical manifestations are actually quite limited. Patients report feeling a slight tingle or, feeling weak and lethargic one moment, and literally energized the next.

It is clear that those patients in the poorest health get the most benefit from implanted defibrillators. Yet, one must also consider that patients with chronic heart disease, those with comparatively good heart function, are not helped by them. This fact needs to be kept in mind as the number of I.C.D.’s implanted is going up at a rate of greater than 20 percent each year.

A study carried out in 1996 examined 196 patients at various medical centers all over the country, all of whom had suffered a minimum of one heart attack before. The purpose of the study was to compare the life-saving features of the defibrillator to the severity of the patients’ heart disease. Based on this study, it was found that high-risk patients benefited greatly from the implantation of an I.C.D. Now, over 150,000 people all over the world have an implanted defibrillator, and it’s a certainty that they save lives. Its creation is the culmination of approximately twenty years of biomedical research.

Monophasic Defibrillator. Big words. So, to the average person, what do they mean? They represent the standard defibrillator used in most hospitals, and the device gives a single pulse of electrical energy that goes in one direction between the two pads (or paddles) that are applied to a person’s chest. If a recording were made of this, it would show a single (monophasic) wave.

In a normal, healthy heart, its beat is regulated by electrical impulses that start in the sinus node. Sounds like it should be describing something in the nose; but, in fact, it is the natural pacemaker for the heart. From there, it fans out across the heart muscle along special tissue and causes the atria and ventricles to contract and expand in a regular pattern. The result? The heart fills and empties in a systematic fashion, thus insuring it fulfill its vital function for the continued life of the individual.

But, often there comes a time when the heart goes into what is known as Ventricular Fibrillation (VF), and then its organized electrical activity malfunctions, replaced by utter chaos. The result? The heart no longer fills and empties. Instead, it quivers (or fibrillates) and stops pumping altogether. If it is not corrected within several minutes, brain damage, nerve damage and/or death will result. That’s where a defibrillator comes in. It delivers an electrical jolt that, in essence, gives the chaos a "time-out" and allows the heart a chance to restart its regular electrical activity.

In order to work properly, a monophasic defibrillator often has to use high levels of electrical power. Often, a first jolt will be 200 joules. If a second shock is needed, the level rises to 300. If that fails, the device is increased to its highest level, 360 joules.

On the other hand, with a biphasic defibrillator the electricity goes from one pad, through the chest, to the second pad, and back. It reverses and therefore travels in two directions. As a result, it gives two jolts of electrical energy, and does so using less energy than a monophasic defibrillator. Rather than start with 200 joules, a biphasic device uses 100 to 150 joules, and 200 is normally the maximum amount.

Finally, the biphasic defibrillator has the ability to adjust itself based on the patient. It’s no secret that different people have different body types. As a result, the degree to which they resist the flow of electricity through their chest also differs. A biphasic defibrillator can determine this and modify the jolt it delivers, and improve the patient’s chance for survival. The monophasic defibrillators do not have this feature.

Defibrillators save thousands of lives everyday, but you may be wondering, "What is a defibrillator and how does it work?" Simply put, a defibrillator is a machine that sends an electrical current to a person’s heart in order to shock the heart back into a normal heart rate. Defibrillators are often used in cases of sudden cardiac arrest.

When a person suffers cardiac arrest, they lose consciousness and cease normal breathing. Although the terms are commonly interchanged, a cardiac arrest is different than a heart attack. Strictly speaking, with a heart attack a person suffers from a blockage of the arteries and may experience chest pain and other symptoms. Generally, heart attack victims do not lose consciousness.

Cardiac arrest is caused by ventricular tachycardia or ventricular fibrillation. Here, the heart beats too fast and shuts down, no longer pumping blood throughout the body. This can result in sudden cardiac death.

In the past, defibrillators were used only in hospitals because the units were large and expensive. Hospital units are still more expensive than home models and they work by sending an electrical impulse through paddles placed on a person’s chest. Today, however, units exist that are portable and that are implanted into a patient’s chest.

Automated external defibrillators, or AEDs, are becoming more common in places like schools, businesses, and sporting events. These portable units are about the size of child’s lunchbox and can be used by individuals with limited training. In fact, many of these units audibly guide users through a series of steps to help the patient.

The AED reads the patient’s heart rate rhythm and administers an electrical current to the heart. Studies show that the more quickly defibrillation treatment is given, the more likely a patient is to survive. Although CPR can sustain an individual, it cannot restore a patient’s heart rhythm like a defibrillator can.

If someone is experiencing sudden cardiac arrest, call 9-1-1 and administer a defibrillator as soon as possible. Acting quickly can save the patient’s life.

Thus, the question, "What is a defibrillator" is an important one for parents, teachers, and caretakers to consider. A defibrillator can save the life of someone experiencing cardiac arrest.

In 2001, Vice-President Dick Cheney had a battery operated defibrillator implant put into his chest to help correct his heart problem. Implants like the one in the Vice-President shock the heart back into a normal rhythm when it’s beating irregularly. Doctors may recommend this treatment after a patient has suffered a heart attack or has the potential for one because of irregular rhythms.

A defibrillator implant continually monitors the patient’s heart rate and applies a treatment when an abnormal rate is detected. One of the heart rate problems that defibrillator implants treat is a rhythm that is too fast. When the heart beats too fast, not enough blood enters the ventricles between pumps, essentially rendering the heart’s pumps ineffective. A defibrillator does not cure heart problems, but it does provide a sort of safety net for individuals at risk for cardiac arrest or rapid heart rates.

Research on implants suggests that these devices save lives. In the past, medical professionals used external defibrillators to shock the system during a heart attack. New advances, however, have created ways of implanting similar devices within the body for individuals at high risk for hearth problems.

Although defibrillators can be implanted soon after a heart attack, studies show that benefits are greater for long term treatment. One study suggests that patients should wait for several months after a heart attack to have a defibrillator implanted. However, more research is needed on both long and short term effects and treatment to fully understand a defibrillator’s influence.

Many individuals who have had a defibrillator implant report positive changes in their health, including not feeling dizzy or fainting as frequently. Patients also say that they feel more comfortable leaving their homes and engaging in daily activities like they used to before heart problems interrupted their lives. Rather than being confined to their homes or towns in case something went wrong, patients can now travel with the confidence that the defibrillator will help keep their heart working properly.

Individuals with heart problems should continue with regular medical treatment and appointments after the implant. Some systems come with portable monitors that doctors can use to track heart rhythms and find potential problems.

If you suffer from a heart condition or have had a heart attack in the past, you should discuss with your doctor whether a defibrillator implant is right for you. Not everyone needs an implant or will find one helpful. However, for others the implant will give them their life back.