Is a cardiac pause (heart pause) harmful?

From the Guidelines

A heart pause is not necessarily bad, and in most cases, especially in young individuals and athletes, it can be a normal phenomenon due to heightened vagal tone, and does not require treatment. According to the 2018 ACC/AHA/HRS guideline on the evaluation and management of patients with bradycardia and cardiac conduction delay 1, sinus bradycardia and pauses can be common during rest and sleep, and are often asymptomatic. Some key points to consider include:

• Sinus bradycardia and pauses are common in individuals with dominant parasympathetic tone, such as athletes and during sleep 1
• In almost all cases, patients with sinus bradycardia and pauses are completely asymptomatic and do not require anti-bradycardia therapy 1
• Permanent pacemaker (PPM) implantation is not indicated for asymptomatic or minimally symptomatic patients, even if they have electrophysiologic evidence of sinoatrial node dysfunction (SND) 1
• The benefit of PPM implantation is essentially symptom relief and quality of life (QOL) improvement, and is associated with surgical risk and long-term consequences 1

It's essential to note that while heart pauses can be normal in certain situations, they can also be a sign of an underlying condition that requires medical attention. If you experience symptoms like dizziness, fainting, or shortness of breath with heart pauses, it's crucial to seek immediate medical care. Regular cardiac monitoring is also important if you've been diagnosed with heart pauses to track their frequency and duration.

From the FDA Drug Label

Bradycardia, including sinus pause, heart block, and cardiac arrest have occurred with the use of metoprolol. Patients with first-degree atrioventricular block, sinus node dysfunction, or conduction disorders may be at increased risk. Monitor heart rate and rhythm in patients receiving metoprolol. If severe bradycardia develops, reduce or stop metoprolol

A heart pause, also known as sinus pause, can be a sign of bradycardia, which is a potential adverse reaction to metoprolol.

• Bradycardia can lead to cardiac arrest in severe cases.
• Patients with pre-existing conduction disorders may be at increased risk.
• Monitoring of heart rate and rhythm is recommended for patients receiving metoprolol.
• If severe bradycardia develops, the medication should be reduced or stopped 2.

From the Research

Heart Pauses: Understanding the Risks

• A heart pause, also known as a ventricular pause, is a period of time when the heart stops beating or beats very slowly 3.
• According to a study published in 1985, ventricular pauses of 3 seconds or longer are uncommon and usually do not cause symptoms 3.
• However, another study published in 2018 found that intermediate pauses, defined as pauses of 2 to 3 seconds, are associated with increased cardiovascular risk and mortality, especially when they occur during the daytime 4.

Causes and Consequences of Heart Pauses

• Heart pauses can be caused by various factors, including sinus arrest, atrial fibrillation with slow ventricular response, and atrioventricular block 3.
• A study published in 2022 found that metoprolol, a beta-blocker medication, can improve myocardial remodeling and cardiac function in patients with permanent pacemaker implantation, which may help reduce the risk of heart pauses and other cardiovascular complications 5.
• Another study published in 2023 discussed the recent advances in cardiac pacemaker technology and its role in managing complications related to heart pauses and other heart rhythm disorders 6.

Management and Treatment of Heart Pauses

• The management and treatment of heart pauses depend on the underlying cause and severity of the condition 3.
• Permanent pacemaker implantation is a common treatment option for patients with symptomatic heart pauses or other heart rhythm disorders 6.
• A study published in 2015 found that the optimal interval for pausing chest compressions to analyze the cardiac rhythm during cardiopulmonary resuscitation is still unclear, and more research is needed to determine the best approach 7.