OVERVIEW

What is sinus arrest?

The heart's normal pacemaker is called the "sinoatrial node." Electrical signals from the sinoatrial node spread throughout the heart, enabling normal heartbeat.

Sinus arrest, also known as sinus pause, occurs when the sinoatrial node malfunctions and stops working due to ischemia, injury, drug toxicity, or other reasons, failing to generate electrical signals. This results in a temporary cessation of atrial or whole-heart contractions. Symptoms mainly include dizziness, blackouts, or loss of consciousness, and severe cases may even experience convulsions.

To treat sinus arrest, the underlying condition affecting sinoatrial node function should be addressed. Additionally, symptomatic patients may use medications to increase heart rate, while severe cases may require an artificial pacemaker.

Is sinus arrest serious?

Brief sinus arrest is generally not serious. The longer the sinus arrest persists, the more life-threatening it becomes.

Are sinus arrest and sinus pause the same condition?

Sinus arrest is also referred to as sinus pause, sinus standstill, or sinus inactivity—all terms describing the same condition.

How is sinus arrest classified?

Sinus arrest is typically categorized based on the duration of the pause:

• Brief pause: Lasting 2–4 seconds.

• Prolonged pause: Lasting over 4 seconds, sometimes exceeding 8 seconds.

• Permanent pause: The sinoatrial node permanently stops functioning.

SYMPTOMS

What are the common manifestations of sinus arrest?

Brief pauses: May cause no noticeable discomfort or only mild palpitations and dizziness.

Prolonged pauses: May lead to vertigo, blurred vision, or brief loss of consciousness; severe cases may even result in convulsions.

How does sinus arrest progress?

In its early stages, sinus arrest is difficult to detect. Some patients may experience no discomfort and only discover it incidentally during an electrocardiogram (ECG) examination.

The progression of sinus arrest depends on its underlying cause, with different diseases leading to varying rates of progression.

As the duration of cardiac arrest prolongs, symptoms of discomfort gradually appear, prompting patients to seek medical attention.

What severe consequences can sinus arrest cause?

If cardiac arrest lasts too long and no alternative ectopic electrical activity occurs, it may lead to acute cardiac brain ischemia syndrome, which is life-threatening and requires emergency treatment.

CAUSES

What diseases commonly cause sinus arrest?

• The most common causes are various heart diseases, such as coronary heart disease, acute myocarditis, and cardiomyopathy.

• After the normalization of tachyarrhythmia, transient sinus arrest (2–4 seconds) may occur, most commonly seen in supraventricular tachycardia.

• Overdose or poisoning from certain antiarrhythmic drugs can affect sinoatrial node function and lead to sinus arrest, such as digoxin, amiodarone, and propafenone.

• Normal individuals may also experience sinus arrest when pressing on the eyeballs, forcefully squeezing the neck, or stimulating the throat.

• Damage to the sinoatrial node during cardiac surgery may result in sinus arrest during or after the operation.

• Trauma, such as car accidents or stab wounds, that injures the sinoatrial node can cause sinus arrest.

• Abnormally high or low potassium ion levels in the blood can also lead to sinus arrest.

Is sinus arrest contagious or hereditary?

Sinus arrest is neither contagious nor hereditary.

DIAGNOSIS

How is sinus arrest diagnosed?

Doctors primarily rely on electrocardiograms (ECG) to diagnose sinus arrest.

What tests are needed when sinus arrest is suspected?

An ECG can usually detect sinus arrest.

However, some people experience intermittent sinus arrest, which may not occur during a standard ECG. In such cases, doctors may recommend a 24-hour or longer Holter monitor test to capture ECG changes during an episode.

What should be noted during an ECG for sinus arrest?

A standard ECG is quick and convenient, with no special preparation required. However, it is best performed during symptom episodes to more easily "capture" sinus arrest.

During Holter monitoring, avoid intentionally resting in bed—maintain normal daily activities and work routines. Additionally, some hospitals require appointments for Holter tests, so they may not be available on the same day as the consultation.

TREATMENT

Which department should I visit after sinus arrest occurs?

You should see a cardiovascular specialist. Remember to bring your previous medical records and provide the doctor with a detailed medical history.

How should sinus arrest be treated?

The treatment of sinus arrest primarily focuses on addressing the underlying cause, meaning active treatment of the primary condition causing the sinus pause is essential.

For individuals without other diseases, occasional, transient, and asymptomatic sinus arrest with a heart rate above 50 beats per minute usually does not require special treatment.

For frequent or prolonged episodes of sinus arrest with obvious symptoms such as dizziness or fainting, medications like atropine or isoproterenol may be tried.

For cases with recurrent syncope, seizures, and ineffective drug treatment, the placement of a permanent artificial cardiac pacemaker should be considered.

Does sinus arrest require hospitalization?

Patients with frequent episodes and obvious symptoms requiring medication should be hospitalized for observation and treatment.

Hospitalization is necessary for those who need an artificial cardiac pacemaker.

Is the placement of an artificial cardiac pacemaker painful during sinus arrest?

The placement of an artificial cardiac pacemaker is a minimally invasive procedure with small surgical trauma and quick postoperative recovery, so the discomfort is minimal.

DIET & LIFESTYLE

What should patients with sinus arrest pay attention to when receiving a permanent artificial pacemaker?

After pacemaker implantation, daily life will not be significantly affected. However, the following precautions should be taken:

• Protect the skin over the pacemaker site to avoid impact or rubbing.

• For the first week after surgery, avoid raising the arm on the surgical side overhead or engaging in vigorous activities. Within three months post-surgery, refrain from strenuous movements or strong impacts on the surgical-side arm.

• Household appliances can be used normally, but avoid strong magnetic fields and keep magnets away from the pacemaker. Try not to use the ear on the same side as the pacemaker for phone calls.

• Learn to check your pulse to monitor the pacemaker's function, such as measuring it every morning upon waking or after sitting quietly for 15 minutes.

• Patients with pacemakers should attend follow-up appointments at 1 month, 3 months, 6 months, and annually thereafter to ensure proper functioning. As the battery nears its lifespan, increase the frequency of check-ups.

• Always carry a pacemaker ID card. Inform medical professionals about the pacemaker during visits. Present the card to bypass personal security checks when boarding a flight.

PREVENTION

How to Prevent Sinus Arrest?

• Have regular check-ups. People with chronic diseases such as hypertension or diabetes should follow their doctor's instructions for standardized treatment.

• Individuals with a naturally slow heart rate should monitor their blood pressure and pulse daily, paying attention to changes in heart rate and personal sensations. If experiencing significant discomfort, an ECG should be performed promptly. Seek immediate medical attention in case of fainting or seizures.

• Maintain a cheerful mood, avoid extreme emotional fluctuations, balance work and rest, prevent staying up late or mental stress, avoid excessive alcohol consumption, and guard against colds.