Pacemaker

A normal resting heart beats around 60 to 100 times per minute in case of adults and 70 to 100 times in case of small children. However, due to some defects in the electrical signals coordinating the heartbeats, certain people may experience irregularity in heartbeats i.e. their heart either beats too slowly(bradycardia) or too fast (tachycardia) in comparison to a normal heart. This condition is commonly known as arrhythmia. A pacemaker is a tiny, electrical device implanted in the chest or the abdomen to regulate normal heart rhythms in patients suffering from arrhythmia.Although there are various different types of arrhythmia, pacemakers are generally used to treat bradycardia and tachycardia.

How does a pacemaker work?

A pacemaker has two parts- the pulse generator and the leads. The former consist of a battery and electronic circuitry with a small computer fitted in a tiny metal case and the latter consist of insulated wires called leads that carry the electrical signals from the pulse generator to your heart.

The pacemakers start working when they detect any abnormality in the heart rhythm, even if it’s a slight one. It sends electrical signals to the heart to balance the normal rhythms. Pacemakers have special sensors that precisely detect body motion and breathing rate which enables them to send electrical impulses when required by the patient.

The type of pacemaker you need depends upon the area of the heart affected and the adversity of your condition. There are three different types of pacemakers:

• Single Chamber Pacemaker- As the name clearly indicates, this is used to stimulate only a single chamber of the heart, specifically on the right side which means that the lead carrying the electrical impulse is connected to the right ventricle or the right atrium.
• Dual-Chamber Pacemaker- The leads carrying the electrical impulse are connected to the right ventricle and the right atrium simultaneously. This helps to regulate the timely and coordinated contraction of both.
• Biventricular Pacemaker- These are used for biventricular pacing (commonly known as cardiac resynchronization therapy) to simulate the left and right ventricles in patients experiencing heart failure due to abnormal electrical systems.

Pre-surgical tests and screenings-

In order to determine your eligibility for the procedure and to figure out the type of pacemaker you need, you will be required to undergo certain tests and screenings. These include:

• Electrocardiogram (ECG), which is used for measuring the electrical impulses of your heart.
• Holter monitoring for detecting unpredictable and suddenrhythm disturbances. You will be required to wear a small monitor for a day or two in order to trackthe electrical activity of the heart while you carry on with your normal day to day activities.
• Echocardiogram, which involves the use of a transducer to produce sound waves that generate patterns which help the doctors to determine any abnormality in your heart function.
• Stress test. Some heart problems occur only during exercise. For a stress test, an electrocardiogram is taken before and immediately after walking on a treadmill or riding a stationary bike. In some cases, an echocardiogram or nuclear imaging are done.

Pacemaker placement procedure:

The procedure is carried out under the influence of local or general anaesthesia which may be given intravenously. The area is sterilised properly and an incision is made to introduce the leads into one of the major veins and then guided towards the heart using a special imaging technique. The ends of the leads are secured carefully with the affected chamber on one end and the pulse generator on the other. The latter is implanted right below the skin in the chest or abdomen. The pacemaker is programmed to suit your specific requirements.

Post-surgical precautions:

After undergoing pacemaker placement, you will be required to follow a few guidelines in order to negate unnecessary complications.

• You are required to refrain from indulging in vigorous activities for at least a month.
• Avoid putting pressure or strain over the concerned area.
• While talking on a cell phone, try to maintain a distance of at least 6 inches in between.
• Do not undergo any medical screening or imaging test without informing your doctors about the pacemaker.
• Stay away from power generating equipment like transformers and welding machine.
• Although you can [pass through a metal detector without any problem, avoid leaning against it or staying nearby for too long.

Benefits

• It helps to relieve the various symptoms associated with arrhythmia. These include light-headedness, fatigue and restlessness.
• The pacemaker requires very low maintenance.
• A pacemaker usually lasts for around 10 to 15 years