What is Normal Sinus Rhythm?

Normal sinus rhythm is when the electrical impulse in your heart is generated in the sinus node and is properly transmitted throughout the heart leading to a coordinated contraction. Your heart is beating optimally when it is in a normal sinus rhythm.

How Does Your Heart Generate A Sinus Rhythm?

Your heart is made up of a multitude of cells that all have the potential to generate an electrical impulse and cause contraction of the heart muscle. A specialized area of the heart called the sinoatrial node is designated to start the electrical impulse. From there, it travels throughout the heart.

Your heart has two upper chambers called atria and two lower chambers called ventricles. The sinoatrial node is located in the right atria. The impulse travels throughout the atria, pauses at the atrioventricular node, and then is transmitted throughout the ventricles.

The pause at the atrioventricular node allows time for the atria to contract. After the electrical impulse is transmitted through the ventricles, the ventricles contract.  

Medical Conditions that Can Affect Normal Sinus Rhythm

Medical conditions can affect how well the electrical impulse travels through the heart. For example, coronary artery disease can decrease blood flow to a section of the heart. The electrical impulse cannot travel through this section and must bypass it. This increases the likelihood that an abnormal electrical impulse will occur.

From symptoms alone, it is difficult to determine how serious a heart condition may be. If you are having symptoms of heart disease, seek emergency treatment. If you have questions or concerns about whether your symptoms may be related to your heart or you have milder, persistent symptoms, a doctor on call can look at your heart tracings and discuss treatment options.

Clinical Applications of ECG Monitoring with Abnormal Sinus Rhythms

Electrocardiograms are tracings of the electrical activity in the heart. Your doctor uses these tracings to identify abnormal heart rhythms and follow the effects of medications designed to modify your heart rate or contractility.

Bradycardia

Your heart rate is the number of times it beats per minute. For most people, resting heart rate falls between 60 beats per minute (BPM) and 100 BPM. It is considered bradycardia if your resting heart rate is below 60 BPM.

If you are a well-trained athlete, your heart may beat more efficiently than most. Your heart can pump the same amount of blood using fewer contractions. This is not a sign of illness. Typically, your heartbeat also slows during the deeper stages of sleep.

For some people, bradycardia is abnormal. In this case, a slower heartbeat result in less blood being distributed to the body and can cause symptoms such as lightheadedness and dizziness. If it persists or worsens, bradycardia can also cause confusion, disorientation, and loss of consciousness. It can cause heart failure, frequent fainting, and cardiac arrest in extreme cases.

Medical conditions associated with bradycardia include the following:

• Heart damage
• Heart inflammation
• Conduction problems
• Congenital heart disease
• Infection of heart tissue
• Low thyroid function
• Electrolyte abnormalities
• Obstructive sleep apnea
• Aging-related heart changes
• Certain medications

Tachycardia

Sinus tachycardia is when your heartbeat is faster than 100 bpm. It is common to have sinus tachycardia in situations such as when you are:

• Exercising
• Stressed
• Consuming caffeine
• Febrile
• Taking certain medications

When your resting heart rate remains elevated, it can increase your risk for certain medical conditions. When your heart beats too fast, it does not allow enough time for the ventricles to fully fill and pump blood from the heart. This can cause symptoms such as:

• Heart palpitations
• Lightheadedness
• Shortness of breath
• Dizziness
• Fatigue
• Fainting
• Chest pain or tightness

If you have an elevated heart rate at risk and it persists, contact your doctor. An online doctor at Telegra MD can help you with an online diagnosis by determining whether your faster heartbeat is expected and healthy or a sign of a medical condition.

Atrial Fibrillation

Atrial fibrillation is an abnormal rhythm that may occur when atrial cells, not in the sinoatrial node, depolarize and send an electrical impulse. It causes an irregular heartbeat that is commonly much faster than it should be.

Atrial fibrillation can be diagnosed using the tracing on an ECG/EKG or Holter monitor. Medications can stabilize the heart rate and decrease the risk of blood clots. Online doctors provide 24-hour access to care and can help you manage atrial fibrillation and prevent complications.

Long-Term Implications of Abnormal Sinus Rhythm Arrhythmias

When the atria fibrillate, they generate frequent, ineffective contractions. Blood sits in the atria longer, which increases the risk of blood clots. Untreated atrial fibrillation increases the risk of stroke, heart attacks, and heart failure.

Technologies for Detecting and Monitoring Sinus Rhythm 

Many heart arrhythmias do not cause symptoms and are discovered incidentally or on a routine physical exam. With the widespread use of wearable technology and remote patient monitoring systems, heart arrhythmias can be discovered earlier and tracked better than when the only option was a periodic ECG.

Wearable Technology

Many smartwatches track heart rates, and some even monitor ECG and blood pressure. With wearable technology, you can identify arrhythmias, such as atrial fibrillation, before any symptoms develop. These devices provide more insight for doctors on how your heart is behaving throughout the day, not just during the few seconds you are monitored with an ECG. This can lead to better diagnostic capabilities.

Wearable technology can also help track patient compliance and outcomes when medication changes are made.

Remote Patient Monitoring Systems

Remote patient monitoring systems monitor a patient’s health outside the hospital and other clinical settings. These devices collect patient information and transmit it to a healthcare provider. This is especially useful for people with chronic medical conditions, recent hospitalizations, or reduced access to medical facilities.

While monitoring, whether self or through remote patient monitoring, is important and has a role in healthcare, getting a medical consultation to evaluate your healthcare data is still important.

Disclaimer

While we strive to always provide accurate, current, and safe advice in all of our articles and guides, it’s important to stress that they are no substitute for medical advice from a doctor or healthcare provider. You should always consult a practicing professional who can diagnose your specific case. The content we’ve included in this guide is merely meant to be informational and does not constitute medical advice.