About the disease
Sick sinus syndrome is a chronic slowing of heart rhythm. During the sick sinus syndrome the sinus code, which acts as a pacemaker in the heart, weakens or stops functioning. Sick sinus syndrome usually manifests in heart rate. Slow heart rate is also known as bradycardia. It can also result in ectopic arrhythmia. The biggest complication of sick sinus syndrome is sudden cardiac arrest, which may result in death. Sick sinus syndrome mostly affects people over 60-70 years of age. In rare cases sick sinus syndrome can develop among children. It is equally common in both females and men.
Sinus node is a pulse generator and it controls the heart rate. Generally, sinus node generates electrical pulses at a frequency of 75-85 per minute. For patients with sick sinus syndrome frequency of electric pulses much less. According to Journal Of The American College of Cardiology, there is an increasing number of SSS cases because of increasing longevity of population age. It was estimated that by 2060 there will be about 170 000 cases of this disease per year.
In general, there are two types of sick sinus syndrome: cerebral and cardiac. Symptoms of cardiac sick sinus syndrome include heart rhythm abnormalities accompanied by fatigue, irritability, forgetfulness and emotional instability. Elderly people suffer from the memory loss and discordance of some speech functions.
People who have cardiac sick sinus syndrome can often lose consciousness. A patient may faint several times per day for one or two minutes. Before fainting he may hear noise in the ears and feel weakness, which are also symptoms of cardiac arrest. Usually fainting happens without any warning.
Skin of patients with cerebral sick sinus syndrome is pale and constantly cold. They can also experience cold sweats during the night In this case blood pressure drops sharply. Fainting sometimes may be provoked by cough or by sharp turn of the head. Also wearing shirt with tight collar can result in fainting episode.
- Development of cardiac asthma
- Pulmonary edema
- Coronary artery disease
- Myocardial infarction
With the progression of sick sinus syndrome patients may develop tachycardia or fibrillation, which may result in sudden cardiac death.
- SSS is usually diagnosed during ECG monitoring, when number of heartbeats is less than 90 per minute.
- Doctors can also identify sick sinus syndrome by MRI screening.
- Another common sick sinus diagnosis is the so-called Holter monitoring, when patient is being observed by doctors for the period of 24 hours. The main purpose of Holter monitoring is to understand if there is a sinus node dysfunction. Another way to determine if a patient has sick sinus syndrome is to make him exercise. Usually healthy people experience heart rate increase while running, jumping or moving fast.. This is not the case for people with sick sinus syndrome. Although their heart rate accelerates a bit, it still remains very low comparatively to people who do not have the similar problem. Sometimes doctors try to assess the response of patients to an excessive amount of oxygen by giving them oxygen masks and seeing the reaction of the heart . Patients with sick sinus syndrome have a decreased heart rate, which is another indicator of bradycardia.
- Coronary angiography is used to assess state of coronary arteries.
Choice of sick sinus syndrome treatment (SSS) depends on the degree of heart rhythm abnormalities, arrhythmia and severity of medical symptoms. Most effective treatment option is pacemaker implantation
Pacemaker implantation is required if patient has chronic heart failure and there is a possibility of sudden cardiac death. The pacemaker generates impulses and increases heart beat until it becomes normal. It is also good for the elderly, because usually their heart welcomes the introduction of the device, which can support the heart rhythm. The only problem is that heart can get used to the pacemaker very quickly, that`s why it patients who undergo this kind of therapy are likely to have to wear the pacemaker for the rest of their lives. There were no known complications; although there is a slight possibility that pacemaker may bring some kind of infection. The chances of that are very slim.
Sick sinus syndrome (SSS) usually has a tendency for progression, so if the treatments is suddenly stopped clinical symptoms may worsen and patient may develop other heart diseases.
Sick sinus syndrome prognosis depends on the extent of bradycardia. If there is no treatment, life expectancy can vary from several weeks to 20 years or more. Nevertheless, antiarrhythmic drugs and timely implemented pacemaker may prolong life expectancy for many years.