Pacemaker – Introduction
A pacemaker is an electric heart device that provides electrical signals to the heart. It is implanted into the body of a patient through surgery.
A pacemaker is inserted into a patient suffering from heart disorders such as heart failure, cardiomyopathy, arrhythmia and heart blockage due to some reason etc.
A pacemaker for end-stage heart failure helps in providing some support to the heart, but it is not a long-term solution.
Typically, it is the size of a matchbox and consists of two parts.
- Pulse generator – It is a small battery and electric circuit which helps to generate impulses sent to the heart. These electric signals then travel to the site of action in the heart. This provided impulse helps the muscle to contract and pump blood.
- Leads and electrodes – From pulse generators, one or more leads are connected from one end and the other end of leads are placed inside of the heart. These leads are insulated wires that carry the electric current. Leads are placed in such a manner that they are in direct contact with large veins in the chest that goes to the heart. These leads are placed according to the condition of the heart. An electrode is placed at the end of the lead that touches the heart wall. The leads not only deliver the electric impulse but also keep a record of the heart’s electrical activity and send this information to the pulse generator.
Nowadays, pacemakers are made in such a manner that they change the electric potential of the impulse according to the heart’s electrical activity. There are pacemakers which are leadless and can be implanted directly into the heart of a patient.
Types of pacemakers
A pacemaker helps the heart in different ways by acting on different chambers of the heart.
There are 4 chambers of the heart which pump blood into the body and maintain circulation.
To keep the blood continuously circulating in case of heart disorder, a pacemaker is used.
The pacemaker has the following types:
- Single chamber – These pacemakers only send impulses to one chamber which is the right ventricle of the heart.
- Double chamber – This type of pacemaker is supposed to send an electric impulse to the right ventricle as well as an atrium, hence two chambers of the heart.
- Biventricular chamber – The biventricular chamber pacemaker is implanted into patients who have heart failure or heartbeat problems. These types of pacemakers assist both the right and left ventricles to pump blood more efficiently.
Why is a pacemaker needed?
There are several conditions which require getting a pacemaker as a primary treatment option. Some of the heart block and rhythm problems that require a pacemaker are as listed below:
- Bradycardia – A condition in which the heart beats slower than normal pace. There could be any reason behind it including infection, inflammation, electrolyte deficiency, syndrome or heart block etc.
- Tachy-Brady syndrome – It is a disorder in which the heartbeat alters from being fast and slow including a long pause between heartbeats.
- Heart block – Heart block happens when an electric signal begins from the SA node but gets interrupted midway which causes a delay or breaks in the impulse.
- Heart failure – When the heart muscles get weak and are unable to pump blood efficiently, this condition is known as heart failure.
There could be many other possible reasons/conditions for which the doctor may recommend getting a pacemaker inserted. Sometimes a pacemaker is implanted into a patient who had heart surgery or a heart attack recently as a temporary means of support to the heart.
Common symptoms of heart failure
There are many reasons why a pacemaker is needed as a treatment option. Some of the common signs of heart failure or other disorders are:
- Irregular heartbeat
- Chest pain
- Shortness of breath
These are some of the common symptoms of any heart disorder in which the heart cannot efficiently pump blood to the rest of the body.
How it works
The human heart works on its own with an amazing mechanism. The 4 chambers of the heart work in synchronisation to pump blood into the whole body.
There is an electric impulse provider in the heart which gives signals to these chambers to contract and pump blood. This impulse provider is known as the SA node.
In some heart disorders, this SA node is unable to function properly or due to some other reasons the heart is unable to pump blood systematically. This leads to irregular heartbeats and other complications.
A pacemaker on the other hand is an electric impulse generator that helps the heart muscles to contract and get back in sync for better circulation of blood.
As mentioned above pacemakers consist of a battery, an electric circuit, leads and electrodes. A commonly used pacemaker is implanted in such a way that the battery remains outside the body of the patient.
The leads are inserted into the heart while electrodes are placed inside the heart at the position where an electric impulse is required.
The main objective of a pacemaker is to send an electric signal to the heart and correct the heartbeat. As technology is growing day by day, new innovative pacemakers are now available in the market.
These upcoming models of pacemakers have inbuilt sensors that detect the body movement and breathing rate to determine how much signal the device needs to increase to increase the heart rate.
Risks of pacemaker
Just like any other medical procedure, pacemaker implantation also has some risks associated with it. Some of the common complications are:
- Allergic reaction to sedatives
- Blood clots
- Damaged blood vessels and bleeding
- Punctured heart due to leads
- Scar tissue buildup around leads or electrodes
- Accumulation of fluid around the heart
These side effects are rare and do not affect every patient. Some medications are provided by physicians to control any infection after surgery. Ideally, these side effects go away in a few weeks but if it persists or leads to more complications, contact your doctor immediately.
Although the pacemaker rarely causes any mechanical complications there is a possibility that:
- Leads move out of their place
- Battery dies off
- Programming errors occur in the pacemaker
- Strong magnetic field damages the device
These are some of the rare possibilities, contact your doctor if you face such issues.
Eligibility to get a pacemaker
Before getting a pacemaker implanted, the doctor makes sure that the patient can get it. The doctors run some tests to ensure it is through:
Electrocardiogram – This test is used to measure the heart’s electrical signal activity. Electrocardiogram, which is commonly known as ECG or EKG, is done with the help of electrodes placed on different parts of the body such as the chest, arms and legs. These electrodes receive a signal and send it to a computer attached to them, which graphically represents the electric impulses. It helps to determine the pace at which the heart is beating.
Echocardiogram – echocardiogram is an imaging test that uses sound waves to produce an image of the heart of the patient. It helps to determine the size, muscles and valves of the heart. It gives a clear view of how much the muscles of the heart are affected and how the chambers and valves are working.
Holter monitor test – It is a test that checks the rhythm of the heart. This test involves wearing a device for two days to monitor the rhythm of the heart of a patient. It checks if the heart is beating irregularly and records the electrical activity of the heart for two days. This test is usually performed when ECG is unable to provide essential information.
Stress test – This is an electrocardiogram test that is taken twice, before and after exercise. Sometimes heart problems only affect during exercise and hence stress test helps to determine the heart’s ability to function when the external stress is applied.
The doctor will analyse the result of these tests and decide whether a pacemaker is a good treatment option or not. Not every heart disorder requires a pacemaker. In cases like heart failure other treatment options are also available, so discuss all treatment options with your doctor beforehand.
Procedure of implantation
It involves heart surgery to implant a pacemaker in a patient. The procedure is complicated and requires skilled professionals to get the surgery done. Before the surgery day, the doctor will ask the patient to follow some guidelines, which involve:
- Fasting 6 hours before the procedure
- Depending upon the health of the patient, the doctor might give some medications beforehand
- Maintain proper hygiene before the procedure.
The process of implant begins with putting the patient under anaesthesia and sedatives to provide relief from the pain that can be caused due to incision.
The chest of the patient will be cleaned using special soap and a fine incision will be made near the collarbone. The doctor will insert the leads into the veins of the heart.
All this is guided by an x-ray machine for precision. After placing the lead, the doctor will add the electrode to the location at which it should be placed and attach the other end of the lead to the pulse generator.
After attaching both ends the doctor will attach the pulse generator under the collarbone and check the working of the pacemaker.
After ensuring the proper working of the device the doctor will close the incision with stitches. This whole process may take around an hour normally, but if some other complications are there then it might take longer. Whereas some leadless pacemakers make take less than 1 hour to get implanted,
After the implant, the doctors will keep the patient under observation for a day or two. If everything works out fine, then you can go home while taking some precautions on your own.
It may take a few weeks to completely recover and get back to your normal life. If you experience some discomfort or face any major complications, consult with your doctor.
Precautions to take after pacemaker implantation
After getting the implant the patient needs to take some precautions to avoid any electric resistance. Although it is implausible that the pacemaker stops working, taking precautions can prevent any major inconvenience. A few of the precautions are:
1. Keeping the cell phone at a safe distance of 15 centimetres from the pacemaker. Always receive the call from the ear opposite to where the pacemaker is located and avoid keeping your smartphone in the pocket of the shirt.
2. The pacemaker is made of metal and could sound the metal detector; hence it is advised to keep your ID card or any document that represents the proof of pacemaker to avoid any inconvenience.
3. Always tell your medical advisor about the pacemaker so that they can avoid prescribing any medical imaging test that can hinder the working of the device.
4. Avoid going near high-voltage transforms or welding equipment. Always keep a safe distance of 2 feet from any such machines.
Apart from these major precautions, a patient needs to take precautions in their daily life as well. It involves staying away from devices that can disturb the working of a pacemaker in any way. Such devices include microwaves, television, radio, remote control devices etc. If your workplace involves such devices, discuss them with your doctor.
Other better alternatives
A pacemaker is a helpful device that can be used as a treatment option for many heart disorders, but it is not a permanent solution. Several complications come with getting a pacemaker implanted into the body. Apart from that pacemaker also implantation comes with several risks as mentioned above.
In the case of end-stage heart failure, a pacemaker does not come as helpful. Therefore, other heart devices like Left Ventricular Assist Device (LVAD), are used in place of pacemakers to provide better life quality to an end-stage heart failure patient. It is rare to get a heart transplant, and in many cases, it is not a preferable option.
To offer many years of healthy life to an end-stage heart failure patient, LVAD is a better option than a pacemaker. It is always advised to consult a medical professional about your condition and get the best treatment available.