Heart Rhythm Disorders

Normally, your heart beats in a regular rhythm, usually between 60 to 100 times per minute, slower when you’re relaxing or sleeping and faster when you’re exercising. Your heartbeat circulates your blood throughout your body, bringing nutrients to your cells and removing waste. 

With heart rhythm disorders, or arrhythmias/dysrhythmias, the electrical impulses that control the heartbeat don’t work properly. Your heartbeat can be fast, slow or irregular.

Arrhythmias can disrupt your blood flow, so you may notice dizziness, shortness of breath, fatigue or chest pain. They can lead to complications such as blood clots, stroke, heart failure or even sudden cardiac arrest.

Detecting and treating heart rhythm disorders may reduce the risk of complications and improve your quality of life.

Common types of heart rhythm disorders

These are the arrhythmias that are diagnosed most often:

Atrial fibrillation 

Atrial fibrillation (AFib) is the most common type of heart rhythm disorder in the U.S. With AFib, the heart’s upper chambers (atria) beat out of sync with the lower chambers (ventricles). This irregular heartbeat can lead to poor blood flow and increase your risk of blood clots, stroke and heart failure. Symptoms may include palpitations, shortness of breath, fatigue and chest discomfort. 

Treatment usually involves medications to control heart rate and rhythm, blood thinners to prevent clots and sometimes procedures like cardioversion or catheter ablation to make the heart beat normally.

Atrial flutter

Atrial flutter is similar to atrial fibrillation but not as severe. You may not notice symptoms. You may also have episodes of both atrial flutter and atrial fibrillation.

Ventricular tachycardia

Ventricular tachycardia (VT) is a fast heartbeat that begins in the heart’s lower chambers (ventricles). It can be life-threatening, especially if it lasts for a long time or if you have another heart condition. Symptoms may include palpitations, dizziness, fainting or cardiac arrest. VT requires immediate medical attention. 

Treatment options include medications to stabilize the heart rhythm, implantable cardioverter-defibrillators (ICDs) to restore normal rhythm or catheter ablation to get rid of electrical pathways that are triggering VT.

Supraventricular tachycardia (SVT)

Supraventricular tachycardia (SVT) happens when rapid heart rhythms start above the heart’s ventricles. Episodes can be sudden and may cause palpitations, chest discomfort, dizziness or fainting. SVT can be caused by abnormalities in the heart or triggered by factors like stress, caffeine or certain medications. 

Treatment may involve techniques that slow your heart rate, medications that control rhythm or procedures like catheter ablation to correct electrical signals in the heart.

Bradycardia 

Bradycardia happens when your heart rate is slow, typically less than 60 beats per minute. You may not notice symptoms, or you may develop fatigue, dizziness, lightheadedness or fainting. Bradycardia can develop due to aging, medications, heart block or underlying heart conditions. 

Treatment for bradycardia depends on what’s causing it and how severe it is. Options range from lifestyle modifications to pacemaker implantation. Early diagnosis may help prevent complications.

Causes and risk factors

Various factors can make it more likely that you may develop a heart rhythm disorder:   

• Age: As you get older, your heart’s electrical system and your overall cardiovascular health change, increasing your risk. Plus some types of arrhythmias, such as atrial fibrillation, are more common in older adults. 
• Gender: Some types of arrhythmias are more common in men, while others may affect more women.
• Heart conditions: Conditions that make heart rhythm disorders more likely include:
  • Coronary artery disease (CAD)
  • Heart valve abnormalities
  • Cardiomyopathy (diseases affecting the heart muscle)
  • Congenital heart defects
  • Previous heart surgery or procedures
  • Heart failure
  • Myocarditis (inflammation of the heart muscle) 
• Lifestyle factors: Smoking, excessive alcohol consumption, illicit drug use, poor dietary habits and lack of physical activity can increase the risk of arrhythmias. 
• Other medical conditions: These conditions may increase your risk of heart rhythm disorders since they can disrupt your body’s processes:
  • Diabetes
  • High blood pressure
  • Thyroid disorders such as hyperthyroidism
  • Chronic obstructive pulmonary disease (COPD)
  • Sleep apnea
  • Electrolyte imbalances like potassium or magnesium abnormalities
  • Anxiety
  • A severe case of COVID-19 

Symptoms of heart rhythm disorders

If you have a heart rhythm disorder, there may be times when you do not have any symptoms of arrhythmias. But when you do, you may notice:

• Palpitations: Palpitations are a feeling that your heart is pounding, fluttering or skipping beats. Occasional palpitations may not be a sign of a problem. But if they happen frequently or don’t ease up, they could indicate a heart rhythm disorder.
• Dizziness or lightheadedness: You may notice these symptoms when you change position or exert yourself. They occur when your brain isn’t getting enough blood. You may faint or almost faint.
• Shortness of breath: You could have shortness of breath (dyspnea) when your heart isn’t pumping properly. Shortness of breath might be worse when you’re physically active or lying flat.
• Fatigue: It’s common to feel extremely tired with arrhythmias. Since your heart may not be working correctly, your body isn’t getting enough blood flow. You may feel tired even when you’re doing simple, everyday activities.
• Chest pain: Some heart rhythm disorders can cause chest pain, especially if they reduce blood flow to the heart or you have another heart condition. 

It’s important to get medical care if you have any symptoms of arrhythmias. If you have chest pain or shortness of breath, get medical care right away, since these symptoms could be signs of a heart attack.

Learn more about diagnosing and treating heart rhythm disorders.