What do Henry Kissinger, Richard Cheney, Elton John and Roger Moore have in common aside from success in the fields of politics and entertainment? Pacemakers.
A pacemaker is a small (about the size of a matchbox) battery-powered, computer-like device that is implanted in the chest or abdomen to control abnormal heart rhythms. This life-saving gizmo emits electrical impulses to prompt the heart to beat at a normal rate. Pacemakers can be implanted in children, teens and adults.
To fully appreciate the value of pacemakers, we need to understand that the heart has its own internal electrical system that controls the rate and rhythm of our heartbeat.
A group of cells in the heart, called the sinus node or sinoatrial (SA) node, emits an electrical signal that spreads from the top of the heart to the bottom. The electrical signal causes the heart’s two upper chambers, the atria, to contract.
Atrial contraction pumps blood into the heart’s two lower chambers, the ventricles. The ventricles then contract and pump blood to the rest of the body. Each combined contraction of the atria and ventricles is a heartbeat.
When is a pacemaker needed?
There are many reasons why a doctor would recommend a pacemaker. The two most common ones are bradycardia and heart block.
In an adult at rest, the heart usually beats between 60 and 100 times a minute. Bradycardia is a condition in which the heart beats fewer than 60 times a minute.[pq]Heart block is a disorder that occurs if an electrical signal is slowed or disrupted as it moves through the heart.[/pq]
It can be caused by aging, damage to the heart from a heart attack, or other conditions that disrupt the heart’s electrical activity. Some nerve and muscle disorders (e.g. muscular dystrophy) can also cause heart block.
Other conditions that may require a pacemaker include:
- Sick Sinus Syndrome – a condition in which the SA node’s ability to set the correct pace for the heartbeat is compromised by aging or heart disease. Such damage to the SA node can cause slower than normal heartbeats or long pauses between heartbeats. The damage can also cause the heart to switch between slow and fast rhythms.
- Atrial fibrillation (AF) – is the most common type of arrhythmia, a condition in which the heart can beat too fast, too slow, or with an irregular rhythm. AF occurs if rapid, disorganized electrical signals cause the atria to contract very fast and irregularly (fibrillate). AF can increase the risk of stroke and cause heart failure.
- Regular intake of anti-hypertension medicines (e.g. beta blockers) can slow heartbeat too much.
- Fainting and other symptoms of bradychardia – one reason this may happen is if the main artery in the neck that supplies blood to the brain is sensitive to pressure. Just quickly turning the neck can cause the heart to beat slower than normal. As a result, the brain might not get enough blood flow, causing lightheadedness and fainting.
- Heart muscle problems – cause electrical signals to travel too slowly through the heart muscle.
- Long QT syndrome – a disorder of the heart’s electrical activity that can cause sudden, uncontrollable, dangerous arrhythmias in response to exercise or stress.
- Certain types of congenital heart disease or after a heart transplant
Implanting the pacemaker
Placing a pacemaker requires minor surgery, and is usually done in a hospital.
- Before the surgery, an intravenous (IV) line will be inserted into one of the patient’s veins. Through the IV line, the patient will receive a medicine to help him or her relax.
- Using a local anesthetic, the doctor will numb the area where the pacemaker will be implanted, usually in the upper chest. The doctor may also administer antibiotics to prevent infection.
- First, the doctor will insert a needle into a large vein, usually near the shoulder opposite the patient’s dominant hand. The doctor will then use the needle to thread the pacemaker wires into the vein and to correctly place them in the heart.
- Guided by a special kind of x-ray called fluoroscopy, the doctor will pass the wires through the patient’s vein and into the heart. Once the wires are in place, the doctor will make a small cut (about 2 inches) into the skin of the patient’s chest.
- The doctor will slip the pacemaker’s small metal box through the cut, place it just under the patient’s skin, and connect it to the wires that lead to the heart. The box contains the pacemaker’s battery and generator.
- Once the pacemaker is in place, the doctor will test it to make sure it works properly. The doctor will then sew up the incision. The entire surgery takes a few hours.
Living with a pacemaker[pq]Pacemakers generally last five to seven years or longer. In most cases, a person with a pacemaker can lead a normal life.[/pq]
He or she can, with the doctor’s approval, engage in moderate exercise and continue to have sex.
Thanks to advances in device circuitry and insulation, interference risk from machinery (e.g. microwave ovens) has been substantially reduced. However, people with a pacemaker must take certain precautions to ensure safety:
- Keep cell phones at least six inches away from your pacemaker. Avoid carrying a cell phone in your breast pocket over your pacemaker.
- It is generally safe to go through airport or other security detectors. However, you must inform airport security personnel that you have a pacemaker before you go through security, as the device may set off the alarm.
- Remind security personnel that the handheld metal-detecting wand should NOT be held over your pacemaker for more than a second or two. The magnet inside the detecting wand may temporarily change the operating mode of your device.
- Do not lean against or stay near the security detector system longer than necessary.
- Avoid magnetic resonance imaging (MRI) machines or other large magnetic fields.
- Turn off your car engine or other large motors when working on them since these may temporarily “confuse” your pacemaker.
- Avoid certain high-voltage or radar machinery, such as radio or television transmitters, arc welders, high-tension wires, radar installations, or smelting furnaces.
- Keep headphones at least 1.2 inches away from your pacemaker.
- Always inform your doctor or dentist that you have a pacemaker before undergoing any surgical or dental procedure.
- Do not engage in contact sports or any physical/recreational activity that carries the risk of you receiving a blow to the chest.
- Always carry an ID card that states you have a pacemaker.
– Innie Williams RN-BC,WCC, Correspondent – USA with Eric Michael Santos