Key points about sick sinus syndrome
- Sick sinus syndrome is a condition where the sinus node, the heart's natural pacemaker, malfunctions, causing abnormal heart rhythms.
- It can result in slow heart rates (bradycardia), fast heart rates (tachycardia) or alternating rhythms, causing symptoms like dizziness and fainting.
- Age-related degeneration, heart disease, and certain medications are common causes.
- Diagnosis is made with an ECG, Holter monitor and blood tests to assess underlying issues.
- Treatment often involves a pacemaker to regulate the heart rate and medications to manage symptoms.
Common related conditions
Sick sinus syndrome causes
Sick sinus syndrome can be caused by:
- Degeneration of the sinus node due to aging.
- Coronary artery disease or heart attack that damages the heart's conduction system.
- Heart surgery or trauma that affects the electrical pathways of the heart.
- Use of medications like beta-blockers, calcium channel blockers or digoxin.
- Conditions like hypothyroidism or electrolyte imbalances.
Sick sinus syndrome risk factors
Risk factors include:- Older age, which increases the likelihood of age-related degeneration of the sinus node.
- A history of heart disease, including coronary artery disease or heart attacks.
- Previous heart surgery that may have affected the heart’s electrical system.
- Medications that influence heart rate, like beta-blockers or calcium channel blockers.
- Conditions like hypothyroidism, which can affect the heart's conduction system.
Sick sinus syndrome symptoms
Common symptoms of sick sinus syndrome are:- Fatigue, weakness or reduced exercise tolerance.
- Dizziness, lightheadedness or fainting episodes, especially during bradycardia.
- Palpitations or irregular heartbeats during tachycardia episodes.
- Shortness of breath, particularly with physical exertion.
- Chest discomfort or tightness in some cases.
Sick sinus syndrome diagnosis
Sick sinus syndrome is diagnosed using:
- An electrocardiogram (ECG or EKG) to monitor heart rhythms and detect irregularities.
- A Holter monitor to track heart activity over 24-48 hours for intermittent episodes.
- Blood tests to check for thyroid issues, electrolyte imbalances or other underlying conditions.
- An echocardiogram to assess the heart's structure and rule out other potential causes of symptoms.
Sick sinus syndrome treatment
Treatment for sick sinus syndrome may include:- A pacemaker, which is typically implanted to regulate the heart’s rhythm and prevent bradycardia-related complications.
- Medications for any underlying conditions, like thyroid hormone therapy for hypothyroidism.
- Adjusting or discontinuing medications that may contribute to the slow heart rate or arrhythmias.
- In some cases, antiarrhythmic drugs to control episodes of tachycardia.
When to seek care
You should seek medical care if you experience:
- Dizziness, fainting or lightheadedness, especially during physical activity.
- Palpitations or a racing heart, particularly if associated with chest pain.
- Unexplained fatigue or weakness that interferes with daily activities.
- Difficulty breathing or shortness of breath, especially with exertion.