Cardiac Pacemaker
Overview
Our heart is an almost entirely muscular organ that has four chambers with heart valves between the chambers. Our heart contracts to pump blood to the body while it relaxes to receive the venous blood to the heart. Contraction and relaxation occur synchronously.
On the other hand, the pumping rate or the heart rate is balanced against the oxygen and nutrient requirements of the body. A healthy individual's heart rate is 60 to 100 beats per minute. It beats at a lower limit of this range at resting, while it accelerates above this range in situations that increase the body's oxygen need, such as exercise..
An electrical system within the heart tissue regulates the heart rate and rhythm. Electrical impulses generated by the sinus node and the sinoatrial node are transmitted to the heart through the atrioventricular node, followed by the heart's transmission system (electrical system). Thus, the upper two chambers of the heart, the atria, contract and pump blood to the lower two chambers, the ventricles.
Then, ventricles contract to pump the blood to the body and lungs. This coordinated pumping function is accurately preserved. The heart rate and rhythm disturbances are observed when a problem occurs in the heart's electrical system. The impaired electrical system may be the usual consequence of aging, but genetic factors and certain medications may also affect the heart rate and rhythm. In addition, the diseases that damage the heart muscle, such as coronary artery disease, also lead to a similar clinical picture.
The pacemaker is a device consisting of a generator (battery) and wires (electrodes). The generator contains a small electric circuit that sends signals to the heart. Electrical signals generated in the generator are sent or transmitted to the heart using these electrodes.
Why is this procedure done?
Suppose the heart cannot regulate the heart rate and the rhythm. In that case, pacemakers regulate the heart rate and rhythm by producing low-energy electrical signals and sending them to the heart.
When the synchronized, coordinated beat of the heart fails and the heart beats at a rate above or below the physiological ranges, the pacemaker synchronizes and coordinates the rhythm and the rate by producing impulses. While the pacemaker is fulfilling this function, the body's need for oxygen and nutrients is considered.
There are three types of pacemakers: single chamber, double chamber, and biventricular pacemakers. You may seek details about pacemakers from your cardiologist. Your cardiologist will determine the most suitable pacemaker for your problem and explain it to you.
The pacemaker is used to treat the following conditions:
• Acceleration of low heart rate (bradycardia)
• Regulation of abnormal or rapid heart rhythm
• Control of rhythm disorders such as atrial fibrillation
• Coordination of signal transmission between the ventricles, between the atria and between the ventricles and the atria
The coordination of the conduction between the ventricles is called cardiac synchronization therapy (CRT), and it is used in treating heart failure. Pacemaker alone or implantable cardioverter defibrillators can be used in cardiac resynchronization therapy. Implantable cardioverter defibrillator (ICD) plays a role in the treatment of life-threatening arrhythmias. The ICD uses high-energy electric currents to treat the fatal rhythm disorder, referred to as fibrillation.
Risks
Although pacemaker implantation is an invasive procedure, potential risks are low. The life-threatening complications are infrequent.
Any necessary instrument, equipment, and other means to manage the possible risks and complications are available in the pacemaker laboratory, where the pacemaker is implanted.
The risks that can be faced while implanting the pacemaker are listed below:
• Infection
• Bleeding
• Injury or tear of blood vessels
• Anesthesia-related complications
• Allergic reaction against contrast agent
Our specialists will employ all practices to minimize the risk of complications and our doctors will preoperatively inform you about risks listed above and all other potential complications and will address all your concerns.
Preparation
The first phase of preoperative preparation is the same in all Medicana Hospitals. Once your doctor determines that the most appropriate treatment option for your disease is the placement of a pacemaker, your general health is checked to see if you may undergo surgery. If necessary, you will be started on lifestyle changes and diet to prepare you better for the surgery. At the same time, the concomitant diseases, which will increase the likelihood of complications in the surgery, are also treated.
After it is verified that the surgery does not pose a risk, you will be asked to quit smoking if you are a smoker and to stop taking certain medications that increase the risk of bleeding. All other prescribed and over-the-counter medications, herbal products, and supplements will also be questioned, and you will be informed to continue or stop taking them.
When these preparations are completed, and you reach the preoperative phase, the following procedures are performed
• Review of health history
• A detailed physical examination
• ECG, Echocardiography, and Holter monitoring evaluate cardiac functions and structures
• Assessment of the heart's electric system with an electrophysiology study, if required
• Necessary laboratory tests and radiology studies
Assessment by anesthesiologist and other laboratory tests and radiology studies to minimize anesthesia-related complications
You will also be instructed to stop eating and drinking at a particular time before the surgery and you should strictly follow this instruction in order to undergo the surgery at the scheduled date.
Moreover, it is reasonable to plan discharge, post-discharge accommodation, and travel at this phase to manage the postoperative period better.
Surgery and Early Postoperative Period
After you have been taken to the pacemaker implantation laboratory for the procedure, you will be positioned on the procedure table. According to the method determined by the doctor, the procedure may also be performed in the operating room.
If necessary, an IV line is inserted to allow intravenous treatments and administering medications. At this stage, a sedative agent is administered to make you fall into a nap.
All your vital signs will be closely monitored using an ECG, pulse oximeter, and anesthesia monitor.
General anesthesia is usually not required to place a pacemaker. In other words, you will be conscious throughout the procedure, but you can feel slightly sleepy.
The skin is cleaned at the location where the generator will be implanted. A local anesthetic agent is administered before the incision is made. The pacemaker is placed beneath the skin by making an incision on the skin of the rib cage. Electrodes to be connected to the pacemaker are advanced to the heart through a vein. Meanwhile, fluoroscopic imaging is done, a modality similar to angiographic imaging. One end of the electrodes is connected to the heart, while the other is connected to the generator in the rib cage's upper part. The incision made to place the generator is closed.
This method is an endocardial approach and a minimally invasive procedure. This is the most common method. The pacemaker and electrodes are placed on the rib cage.
There is no need to general anesthesia in this procedure.
In the epicardial approach that is less frequently used, the pacemaker is placed beneath the abdominal skin and the electrodes are again advanced to the heart through a vein.
This procedure is carried out in the operating room and requires general anesthesia.
After the pacemaker and electrodes are placed, the surgical part of the procedure is completed.
First, your doctor tests the electrodes. After the signal transmission is verified, the pacemaker is programmed in the light of the pre-operative tests (ECG, Echocardiography,
Holter, Cardiac Stress Test) and the symptoms of your illness.
Placement of a pacemaker takes about 2 to 5 hours.
You will be transferred to the observation room, after the pacemaker is placed. Before you are transferred to the patient room, you should be observed here for a while and it should be verified that all your vital signs are stable or within acceptable limits. If you need critical care, you may be admitted to the intensive care unit.
You will be asked to stay at the hospital for one night after the pacemaker is placed. You will be discharged when your general health is stabilized and your pacemaker's settings are completed.
Before you are discharged, your medications will be planned and prescribed and, suggestions will be made that you need to take into account after the surgery (time to start work, engage in daily life activities and do exercise and sex life etc).
Before being discharged, your doctor will inform you about security systems, magnetic resonance imaging, radiation therapy, and other electrical and electronic devices that may affect the operation of your pacemaker. Security systems, such as ones equipped at airports, will alert because of your pacemaker. You may be given a medical report that your body has a pacemaker implanted in order not to have a problem with security personnel.
You should see your surgeon for follow-up visits that are scheduled before you are discharged.
If you experience warmth and redness in your incision line, or if you have a fever or any symptoms that you think are due to surgery after you are discharged, contact your surgeon immediately.
Results
After the pacemaker is placed and programmed, symptoms (fainting, shortness of breath, exhaustion, fatigue, chest pain) will disappear from the fast or slow functioning of your heart or rhythm disorders
You should take your medicines, as instructed by your doctor, and comply with health lifestyle recommendations. Do not smoke or quit smoking if you are a smoker, and you need to maintain optimal body weight and control your blood pressure, blood glucose, and blood lipids well.
