Pacemaker Implantation

A pacemaker is a device which can be implanted under patient’s chest for treating heart conditions collectively termed as arrhythmia. Arrhythmia is a condition in which the heart of the patient beats at an abnormal rate, which can occur either due to genetic cause or as a result of the normal aging process of heart or damage to the heart due to an attack.

Heartbeat can also be disrupted due to a side-effect of certain harmful medicines. A pacemaker can control the rate of heartbeat, irrespective of the cause behind the condition. It is composed of two parts i.e. a generator and electrodes. A minor surgery is done to implant pacemaker after which a patient has to take certain precautions.

The main reason for implantation of the pacemaker is for controlling the rhythm of heartbeat during the treatment of arrhythmia.

An arrhythmia may lead to an improper supply of blood to vital organs of the body which may cause problems like fatigue, shortness of breath, fainting, damage to vital organs and in severe cases to death.

A pacemaker can thus help a patient with arrhythmia to leave an active life. It is composed of two parts:

• The pulse generator: As the name suggests, this part is responsible for the generation and regulation of the electric pulses to be sent to the heart. It is a small metal container which houses a battery and the electrical circuitry.
• Leads (electrodes): 1-3 flexible, insulated wires which are placed in different heart chambers are responsible for sending the electric pulses, generated by the pulse generator, to the heart for normalizing the rate of heartbeats.

If the pace of the heartbeat is slow, the pacemaker will speed it up by sending electrical signals to the heart and if the pace is too fast the pacemaker will slow it down, accordingly. The pacemaker does this by sensing patient’s breathing rate, temperature, sinus node rate, the motion of the body and other factors.

Based on the number of electrodes, pacemakers can be classified as:

Single chamber pacemaker. It usually carries electrical impulses from the pulse generator to the right ventricle of the heart.

Dual chamber pacemaker. It carries electrical impulses from the pulse generator to both the right ventricle and the right atrium of the heart thus helps in regulation of contractions between the two chambers.

Biventricular pacemaker. It is usually suggested as a treatment option for the patients whose heart’s electrical system has been damaged. This type of pacemaker sends signals to both ventricles so that all or most of the ventricular muscle pumps blood together. As this procedure resets the pumping mechanism of the ventricles, it is also referred to as cardiac resynchronization therapy (CRT).

Although rare, pacemaker implantation also poses risk for some complications, like any other surgical procedure:

• Risk for infection at the site of implantation
• Risk of allergic reaction to the dye or anesthetic drug
• Complications like swelling, bruising or bleeding at the generator site, especially if the patient is taking blood thinners
• Risk of damage to the blood vessels or nerves near the site of pacemaker implant
• Increased risk of lung collapse
• Life-threatening complications in very rare cases.

In preparing for a pacemaker implantation the doctor asks the patient for several tests to monitor the heartbeat, before suggesting pacemaker implantation. Some of these tests could include:

Electrocardiogram: It is a non-invasive test in which electrodes in the form of sensor pads, attached with wires, are placed on the chest and sometimes on the limbs also, to measure the electrical impulses of patient’s heart. This test gives an idea about the pattern of the heart beats.

Holter monitoring: In this test, a battery operated device with its electrodes (wires) on the chest of the patient, is kept in the pocket or worn on a belt or shoulder strap to continuously monitor heart rhythm for a period of 24 hours.

The doctor will ask the patient to keep a record of all the activities and symptoms during this monitoring period. After the monitoring is completed, the doctor will analyze the electrical test result and compare them with the simultaneous record of the activities and symptoms of the patient to figure out the cause of symptoms. This test is also known as an ambulatory monitor.

Echocardiogram: In this test, sound waves are used generate images of beating heart, which help the doctor to monitor heart of the patient without making the incision. In this process, a small instrument known as a transducer is placed on the chest of the patient to pass the sound waves through the heart and then collects reflected sound waves or echoes.

These echoes are transmitted to a machine which generates images of the beating heart by using the pattern of the echo. These images help the doctor to clearly analyze the status of heart and show how well the heart is functioning. The recorded pictures also allow the doctor to measure the size and the thickness of the heart muscle.

Stress test: In this test, the patient is asked to do an exercise like running on a treadmill and an electrocardiogram is taken before and immediately after the exercise to monitor the effect of exercise on the heart.

This test is very helpful for monitoring the status of heart for the patients whose problem occurs only during exercise. In some cases, the doctor may associate an echocardiogram or nuclear imaging instead of an electrocardiogram.

Read on to learn more about what to expect before, during, and after your pacemaker implantation. The doctor will administer local anesthesia at the site of making incision before starting the surgery.

In addition to the anesthetic, a muscle relaxant may also be given to help the patient to relax. As the first step of surgery,the doctor cleans the chest of the patient with an antibacterial agent and an intravenous line in attached to the arm.

The doctor will place the electrodes into the major vein or near collar bone and connect them to the heart. One end of each electrode positioned in the heart and the other end is connected to the pulse generator, usually placed under the collarbone.

After positioning the pacemaker the doctor will close the incision. The doctor will then set the pacemaker as required. The patient may need to stay in the hospital for one or two days.

The patient will need to revisit doctor so that the doctor can confirm that the pacemaker is implanted correctly and working appropriately.

The doctor will advise the patient to take certain precautions as described below:

• Avoid heavy exercises
• Avoid placing cell phones directly on the implantation site
• Try to avoid lingering near metal detection system
• Alway carry an ID proof which states that you have undergone pacemaker implant
• Maintain a distance of at least 2 feet from an instrument which radiates electromagnetic energy like high-voltage transformers, welding equipment, or motor-generator systems.

However, devices like televisions, microwave ovens, toasters, radios, electric blankets, remote controls, electric shavers, and electric drills are unlikely to interfere with the implanted pacemaker.

If you do not understand your pacemaker implantation results, consult with your doctor. With advances in technology, pacemakers have now developed which adjusts the pace of the heartbeat automatically, which allows the patient to continue an active lifestyle.

A pacemaker treats various symptoms associated with heart diseases including lightheadedness, fainting or fatigue. The battery of the pacemaker usually lasts for up to 15 years after which it may be replaced by a very quick surgical procedure.

Over the counter pain relieving drugs with a prior consent of the surgeon can be taken if the patient feels any pain at the implantation site.