Sinus node dysfunction or sinus node disease is also known as sick sinus syndrome (SSS). This is the name of a cluster of heart rhythm problems known as arrhythmias in which the natural pacemaker of the heart known as sinus node does not work to the mark.
The sinus node is an area where there are specialized cells and is situated in the right chamber and controls the heart rhythms. The sinus node is known for producing electrical impulses in a steady pace. The signals are paced in an abnormal manner when a person is suffering from sinus node disease or sinus node dysfunction.
The sufferer of sinus node disease or sinus node dysfunction may have an arrhythmic heart and it may pace too fast or too slow, have a long pause or have a combination of all these things. Although this disorder is rarely seen, there is a risk of developing it with increasing age. Most people with this disease need a pacemaker to keep the heart rhythms in pace.
Causes of Sinus Node Disease or Sinus Node Dysfunction
The heart rate may be exceptionally fast or too slow when a person is suffering from sinus node disease or sinus node dysfunction.
Following are the types of sinus node disease or sinus node dysfunction and their causes:
- Sinoatrial block: In this, the heart rate slows down due to the very slow movement of electrical signals via sinus node.
- Sinus arrest: The activity of sinus node pauses.
- Bradycardia-tachycardia syndrome: The patient's heart beats unusually slow or fast and it is followed by asystole- a long pause.
Why Sinus Node Misfire is Caused?
Sinus node can be affected from the conditions or diseases that have caused damage or scarring to the electrical system of your heart. The scarred tissues from a previous cardiac surgery can also be the reason especially in kids.
Sinus node disease or sinus node dysfunction can be caused due to various medications like beta blockers or calcium channel blockers that are used for treating high blood pressure. In most cases, the node does not work well as the heart muscles get degenerated with age.
Symptoms of Sinus Node Disease or Sinus Node Dysfunction
Some people who suffer from sinus node disease or sinus node dysfunction show a few or zero symptoms in the initial stages. In some people, the symptoms show and then they disappear.
One may see the following symptoms that are associated with sinus node disease or sinus node dysfunction.
- Lightheadedness or dizziness
- Shortness of breath
- Fainting or near fainting
- Bradycardia or slower heart rate
- Chest pains
- A feeling of fast, fluttering heartbeats known as palpitations.
Most of the above mentioned signs are caused due to the reduction in the flow of blood to the brain when the heart beats irregularly.
Risk Factors for Sinus Node Disease or Sinus Node Dysfunction
Infants and people of all ages can be affected by sinus node disease or sinus node dysfunction. People belonging to the age group of 70 are more prone to be suffering from this disorder as it takes time to develop.
Complications for Sinus Node Disease or Sinus Node Dysfunction
Your heart will not be able to perform in an efficient manner when the natural pacemaker is unable to function well. This may cause lowered heart rates that may lead to fainting.
In very rare cases, when the arrhythmic rate of heart takes place for a long time, the heart will not pump enough blood to meet the requirements of the body and this is called as heart failure.
If you are suffering from bradycardia-tachycardia syndrome which is a kind of sinus node disease or sinus node dysfunction, there may be a risk of formation of blood clot in the heart which may cause heart stroke.
Tests to Diagnose Sinus Node Disease or Sinus Node Dysfunction
The signs and symptoms that are associated with sinus node disease or sinus node dysfunction may be commonly linked with many other conditions or diseases.
To get a clear picture about sinus node disease or sinus node dysfunction, the doctor will have to diagnose the condition and find a way to treat it. He or she will then try to connect the dots and determine the relation between the symptoms and the abnormal rhythm of the heart.
Electrocardiogram (ECG) for Sinus Node Disease or Sinus Node Dysfunction
The diagnosis of sinus node disease or sinus node dysfunction normally begins with an ECG or electrocardiogram. However, if the arrhythmias come and go, standard ECG may not be able to record and in such cases, one may need the following types of ECG.
Standard ECG for Sinus Node Disease or Sinus Node Dysfunction
This test includes sensors are attached to the limbs and chest to capture the electrical signals that are travelling through the heart. Certain patterns may be recorded by the sensors that will show the sign of sinus node disease or sinus node dysfunction.
Holter Monitor for Sinus Node Disease or Sinus Node Dysfunction
This is a portable device that can be carried in a pouch or pocket as well as shoulder strap. It will record the heart rhythms for an entire day that will let the doctor a clear idea about its irregularities. This kind of monitoring proves to be extremely beneficial in sinus node disease or sinus node dysfunction diagnosis.
Event Recorder for Sinus Node Disease or Sinus Node Dysfunction
This is also a type of portable electrocardiogram device and can be worn around the body for monitoring the activity of your heart. The doctor may ask to use this device for a month. When you witness the symptoms, you will have to just push the button and ECG will record the signals. The doctor will inspect the pattern and this will help in diagnosing sick sinus syndrome.
Implantable Loop Recorder for Sinus Node Disease or Sinus Node Dysfunction
It is a small device, which is implanted under the skin in the chest area and continuously used for monitoring the electrical activity of your heart. You can wear this implantable loop recorder for months to years.
An irregular heart rhythm (arrhythmia) can trigger the device automatically or, can be triggered manually when one feels the symptoms.
Electrophysiologic Testing for Sinus Node Disease or Sinus Node Dysfunction
It is not a common test that is used for identifying the sinus node disease or sinus node dysfunction. In a few cases, the electrophysiologic testing is helpful to check the functionality of your sinus node along with other electrical properties of the heart.
For this test a thin and flexible tubes are tipped with the electrodes that are threaded through the blood vessels to different spots in the electrical pathways in the heart. When it is placed, the electrode in it can accurately map the flow of electrical impulses with every beat and can figure out the source of the rhythm problem of the heart.
Treatment for Sinus Node Disease or Sinus Node Dysfunction
The treatment of sinus node disease or sinus node dysfunction concentrates on reducing or eliminating the unpleasant symptoms. If you are not troubled by the symptoms, then you just have to go for regular checkup for monitoring your condition. People who are bothered by the symptoms, for them the only treatment choice is to implant an electronic pacemaker.
Medicine Changes for Sinus Node Disease or Sinus Node Dysfunction
The doctor will initially look at the current medications to figure out if any of the medication is interfering with the functionality of the sinus node. The medications that are used for treating the heart disease or high blood pressure, like beta blockers or calcium channel blockers - it could worsen the abnormal heart rhythms. In a few cases, the patient can relieve symptoms just by adjusting the medications.
Pacing the Heart
Some people with the sinus node disease or sinus node dysfunction will eventually need the permanent pacemaker that is artificial. It is to maintain the regular heartbeat. It is a battery-powered, small electronic device that is implanted inside the skin in the collarbone area while conducting the minor surgical procedure. For keeping the beating normal, the pacemaker is designed to stimulate the heart as required.
The kind of pacemaker you require depends upon the type of your irregular heart rhythm. Some of the rhythms can be diagnosed using a single chamber pacemaker that uses only a single wire (lead) to pace one of the chambers of your heart- in such cases- it is atrium.
One will be able resume the near-normal or normal activities once he or she has recovered from the implantation surgery of pacemaker. There is a slight risk of infection or swelling in the region where the pacemaker is implanted.
Additional Treatments for Fast Heart Rate in Sinus Node Disease or Sinus Node Dysfunction
You require additional treatments for controlling the rhythms if you observe rapid heart rate that is a part of the sinus node disease or sinus node dysfunction.
Medicines for Sinus Node Disease or Sinus Node Dysfunction
Your doctor will prescribe you anti-arrhythmia medication if you have rapid heart rate and you have a pacemaker. It will prevent the fast rhythms.
AV Node Ablation for Sinus Node Disease or Sinus Node Dysfunction
It can control faster heart rates in the patients with pacemakers.
This procedure includes the application of radiofrequency energy using a thin and long tube (catheter) that will destroy the tissue surrounding the atrioventricular (AV) node that is between the ventricles and atria. It stops the fast heart rhythms from reaching the ventricles that can cause problems.
Radiofrequency Ablation of Atrial Fibrillation for Sinus Node Disease or Sinus Node Dysfunction
It is similar to the AV node ablation. Well, in this case the ablation focuses on the tissue, which triggers atrial fibrillation. Rather than stopping it to reach the ventricles, it will actually eliminate the atrial fibrillation.
Lifestyle Changes for Sinus Node Disease or Sinus Node Dysfunction
Follow the below steps to eliminate or treat risk factors, which will lead to heart disease:
- Exercise as well as eat a healthy diet. You should live a heart-healthy lifestyle just by regularly exercising and eating healthy food with low fat that involves whole grains, vegetables and fruits.
- Maintain a good weight. The risk of heart disease increases if you are overweight.
- Keep cholesterol and blood pressure under control. Changes in lifestyle are needed. Take proper medication as prescribed by the doctor to correct high cholesterol or high blood pressure.
- Go for regular checkups. Take regular physical exams and you should report any symptoms or sign to your doctor.