How are pacemakers implanted ?

 Pacemaker implantation today is minimally invasive surgery. It is done under local anesthesia, and generally takes less than 45 minutes. There are some steps :

1. First, the area under the collarbone of patient need to numbed,

2. Then, a small incision is made usually about 3 inches long and

3. A “pocket” is fashioned in the tissue overlying the muscle.

4.The leads are inserted through a vein near the site of the pocket, and

5. An advanced into the heart using fluoroscopy (x-rays) for guidance.

6. The leads are then attached to the generator,

7. The generator is placed in the pocket, and

8. The incision is closed.

9. Once a pacemaker is implanted, it is important to program it.

Doctor needs to program the devices in order to suit the individual user. Pacemakers can be programmed non-invasively, with a handheld device that communicates with the pacemaker through the skin. The programming can be repeated as often as necessary if the patient’s underlying heart rhythm problem changes.

Diagram of Pacemakers

1.Single Chamber Pacemaker


A pulse generator, which contains both the battery and the intelligent circuits ,very small in size. This device can be connected to a lead which makes contact with either the atrium or the ventricular muscle.


This diagram shown here are two leads. The one on the top is a lead with a "J" shape, which is used for optimal positioning in the atrium. It is "unipolar", and therefore smaller, and is a "tined" lead which makes passive contact with the atrial muscle.

In contrast, the lead on the bottom is larger because it is a bipolar device which has more wire within it. It has a small screw at the end so that it can be actively fixated to the muscle.

2. Dual Chamber Pacemaker


While for dual chamber pacemakers . Here, a pulse generator is shown which is connected to two leads. It is quite a small device.



The two major types of leads are shown here. On the left is a magnified view of a screw-in lead. The lead on the right is a "tined" lead, which uses the small plastic tines to become passively "stuck" to the muscle in either the atrium or ventricle. In either case, the leads will grow firmly attached to the heart muscle, and will be difficult to remove after 6 months.

               Diagram – How is the pacemaker implant look like in human body.

The pacemaker is implanted by a minor surgical procedure performed under local anesthesia. The wires are placed through a blood vessel beneath the collar bone and positioned in the heart under x-ray. The wires are then connected to the pacemaker, which is placed beneath the skin just below the collar bone.

The surgery usually takes about 1 to 2 hours, and the risk of surgical complications is about 1% to 2%. Usually only a small bump in the skin is seen over the place where the pacemaker has been implanted.

Other than restrictions on heavy lifting and extreme motion of the arm on the side of the pacemaker for several weeks, recovery from the procedure is minimal. Most patients return to normal activities within a few days.
What happens after the pacemaker is implanted?

Once the incision completely heals (which takes about 2 – 4 weeks) the patient can largely return to a completely normal life. There are two common awareness for patient to concern :

1. Periodic pacemaker checks are necessary. It is to measure the function of the device and the amount of energy left in the battery.

a. The “scheduled maintenance” for pacemakers generally consists of periodic telephone follow-up for instance ,every month or two , but usually yearly visits to the doctor office.

b. The telephone follow-up is a simple procedure consisting of placing a special “trans-telephonic follow-up device” over the pacemaker, and transmitting data over the telephone.

2. Pacemaker replacement when the battery begins to get low. This procedure is similar to the implantation procedure, except the pacemaker leads do not need to be replaced.

a. Under local anesthesia, the incision is opened, the generator is detached from the leads and thrown away, a new generator is attached, and the incision is then closed.

What risks can occur with pacemakers? 

 Because pacemaker implantation is an invasive surgical procedure, internal bleeding, infection, hemorrhage, and embolism are all possible complications. Infection is more common in patients with temporary pacing systems. Antibiotic therapy given as a precautionary measure can reduce the risk of pacemaker infection. If infection does occur, the entire pacing system may have to be removed.

· The placing of the leads and electrodes during the implantation procedure also presents certain risks for the patient. The lead or electrode could perforate the heart or cause scarring or other damage. The electrodes can also cause involuntary stimulation of nearby skeletal muscles.

· Besides, it is important for patients to be aware of the symptoms of bradycardia, symptoms that might indicate a pacemaker malfunction. These symptoms include weakness, easy fatigability, lightheadedness, dizziness, or loss of consciousness. Patients experiencing any of these symptoms should notify their doctor. A simple telephone check of the pacemaker is usually enough to rule out a pacemaker problem. It can usually be corrected by the implantation of a dual-chamber pacing system.
What devices can interfere with pacemakers?

Devices Can interfere with Pacemaker

Devices Cannot  interfere with Pacemaker

1. Arc welding equipment and other devices that generate powerful magnetic fields – medical devices and heavy duty industrial motors – can inhibit the function of pacemakers.

2. Radiation therapy for cancers can damage the circuits of a pacemaker, and the pacemaker needs to be shielded from the radiation field.

3. Magnetic Resonance Imaging (MRI) scanners can interrupt the pacing function of pacemakers, and under some circumstances may be dangerous to the pacemaker and the patient. Many problems with MRI can be circumvented by taking special care during the procedure and limiting the MRI scan appropriately. Patients with pacemakers should discuss the risks and benefits of MRI scanning with their doctors.

4. Shock wave lithotripsy, used to break up kidney stones, can potentially damage pacemakers, especially if they are implanted in the abdomen instead of under the collarbone. Pacemakers should be tested after lithotripsy to document that they are still functioning normally.

1. Home appliances do not interfere with pacemakers, and should not cause any concern whatsoever. (This includes microwave ovens, despite the signs you still see posted in some restaurants.)

2. Cellular telephones, if held in close proximity to the pacemaker (which may happen if the phone is kept in a breast pocket) can potentially affect the function of a pacemaker. As long as the phone is kept 6 or more inches from the pacemaker there should not be a problem.