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Identifying and Treating Atrial Fibrillation (AFib or AF)

Identifying and Treating Atrial Fibrillation (AFib or AF)

What Is Atrial Fibrillation?

Atrial fibrillation is a cardiac arrhythmia also known as AFib, or AF. During atrial fibrillation, electrical signals within the atria have deteriorated. This deterioration results in a cardiac rhythm change, such that the heart operates in a disorganized manner where the atria fibrillate, or quiver. The signals from the atria are then sent to the ventricles in a similarly disorganized way, which leads to irregular ventricular contractions.

Because there is a rapid heart rate without a regular or distinctive pattern to the rhythm on an electrocardiogram (ECG), atrial fibrillation is known as an arrhythmia that is irregularly irregular. Collectively, the atria and ventricles are unable to coordinate their contractions, contributing to decreased cardiac output and inconsistent and inefficient pumping of blood to the body. In addition, the fibrillation within the atria may cause pooling of the blood within the chambers of the heart, which can lead to the development of a thrombus (blood clot). The left atria is the most common chamber for thrombus development. A thrombus is at risk for being dispersed when blood is pumped by the heart, traveling to the brain where a stroke may occur. The risk for stroke is increased in patients with atrial fibrillation. In addition to an increased risk for thrombus development and stroke, patients with atrial fibrillation are also at a heightened risk for the development of heart failure, dementia, and a decreased lifespan.

What Are ECG Characteristics of Atrial Fibrillation?

Atrial fibrillation is generally considered a tachyarrhythmia, (an arrhythmia with a heart rate of more than 100 beats per minute). Patients experiencing atrial fibrillation generally have the following characteristics:

What Are Signs or Symptoms of Atrial Fibrillation?

Some patients are asymptomatic and may not know they have atrial fibrillation. If symptomatic, patients may experience one or more of the following:  

What Causes Atrial Fibrillation?

Atrial fibrillation may be caused by acute physiologic stressors, chronic disease, or genetics. Risk factors for the development of atrial fibrillation: 

Treatment of Atrial Fibrillation

To initiate and guide care of the patient, the healthcare provider should utilize the Advanced Cardiovascular Life Support (ACLS) Primary Assessment. Elements of the ACLS Primary Assessment include evaluating the patient’s airway, breathing, circulation, disability, and potential exposure. The healthcare provider should take actions using the ACLS Primary Assessment, including managing the patient’s airway, supplying supplemental oxygen if needed, identifying the patient’s cardiac rhythm, and monitoring vital signs. In addition, it should be determined if the patient has any neurological deficits, and clothing should be removed to perform a visual assessment of the patient for medical alert identification, or potential trauma, burns, or bleeding. Intravenous (IV) access should be obtained, in addition to a 12-lead ECG, if possible. Following the ACLS Primary Assessment, the healthcare provider should utilize the ACLS Secondary Assessment, evaluating H’s and T’s for potential causes of the patient’s condition and gathering a focused medical history. 

The patient’s clinical condition and cardiac rhythm determine which ACLS algorithm will be followed. Questions to consider when making this assessment include: 

Stable tachycardia occurs when the patient has an increased heart rate (more than 100 beats per minute) without any signs of hemodynamic instability; systems within the body remain uncompromised. A patient with stable tachycardia does not have any underlying cardiac electrical factors that would cause the identified rhythm. With stable tachycardia, there is time to evaluate and determine treatment options. Unstable tachycardia occurs when the patient’s markedly rapid heart rate and uncoordinated cardiac contractions contribute to symptoms or hemodynamic instability, due to decreased cardiac output. With unstable tachycardia, it is imperative to move quickly when evaluating and managing the patient’s condition to prevent clinical deterioration of the patient. Patients with atrial fibrillation may present with symptoms or be asymptomatic. If a heart rate is less than 150 beats per minute, it is widely thought that any symptoms present are unlikely to be caused by tachycardia unless the patient has altered ventricular function. 

Unstable Atrial Fibrillation

Upon arriving to the aid of a patient, the healthcare provider should utilize the ACLS Primary and Secondary Assessments as described above. Once the patient’s cardiac rhythm has been identified, the healthcare provider should assess whether the patient has a consistent tachyarrhythmia or tachycardia that is contributing to hemodynamic instability, demonstrated by symptoms such as hypotension, shock, altered mental status, heart failure (acute), or ischemic chest pain. If so, this patient is considered to have unstable tachycardia. As previously mentioned, unstable tachycardia occurs when the patient’s markedly rapid heart rate and uncoordinated cardiac contractions contribute to the development of symptoms or hemodynamic instability due to decreased cardiac output (as can take place with atrial fibrillation). Once it is determined that the adult patient is symptomatic with unstable tachycardia (with a cardiac rhythm such as atrial fibrillation, for example), the ACLS Adult Tachycardia with a Pulse Algorithm should be utilized to guide further evaluation and treatment.


Medications are not utilized to manage the care of patients with an unstable tachycardic rhythm such as atrial fibrillation. However, immediate synchronized cardioversion is indicated. Prior to undergoing cardioversion, sedative medications should be administered in conscious patients. In the unstable patient, cardioversion should not be delayed.


A patient is a candidate for cardioversion if they are experiencing symptomatic tachycardia with a heart rate of 150 beats per minute or more and the patient is considered symptomatically and hemodynamically unstable. However, it is important to note that patients may be symptomatic at heart rates less than 150 beats per minute, particularly if they have existing cardiovascular disease, other risk factors, or potential contributory causes as described above. The healthcare provider must have an understanding of when cardioversion should be utilized, which medications are indicated for cardioversion, how to prepare the patient for cardioversion, and how to operate the cardioverter. The ACLS Electrical Cardioversion Algorithm should be followed to initiate cardioversion in a patient. 

If the patient’s ventricular rate is 150 beats per minute or greater, immediate cardioversion is warranted. Unstable atrial fibrillation requires synchronized cardioversion. Synchronized cardioversion coordinates shock delivery with the peak of a QRS complex based on the patient’s cardiac rhythm analysis. This coordinated delivery can sometimes result in a delay prior to the shock being delivered. The device analyzes the patient’s cardiac rhythm in order to sync the shock delivery with the R wave in the QRS complex. The healthcare provider should have access to the following while performing cardioversion:

If possible, depending on the severity of the patient’s symptoms and how unstable they may be, sedation should be administered prior to cardioversion. Synchronized cardioversion should then be conducted. The healthcare provider should follow the recommendations for their available device to determine appropriate energy level settings for cardioversion. If the patient’s rhythm is refractory following cardioversion, the healthcare provider should re-evaluate the patient for any potential underlying cause. Then, the energy level should be increased for the next cardioversion.

Stable Atrial Fibrillation

ACLS is not utilized to care for the patient with stable atrial fibrillation. The recommendations and algorithms are applicable when atrial fibrillation results in significant signs and symptoms and the patient is hemodynamically unstable.

Next Steps and Considerations

Treating atrial fibrillation aims to reduce the risk of stroke due to thromboembolism and to control the ventricular heart rate. Restoring the patient’s cardiac rhythm to a sinus rhythm may or may not be a goal for all patients. Endpoints of the Adult Tachycardia with a Pulse Algorithm recommend the patient with atrial fibrillation who underwent synchronized cardioversion (whether the cardioversion was successful in converting the rhythm or not) consult with experts for further evaluation and treatment. If the patient with atrial fibrillation is considered stable but has been experiencing atrial fibrillation for more than 48 hours, cardioversion should be delayed until the patient has been properly anticoagulated to reduce the risk of thromboembolism and stroke. Cardioversion for the patient with stable atrial fibrillation would then be conducted under the care of an expert.


Are There Different Types of Atrial Fibrillation?

Atrial fibrillation can be categorized in three ways:

What Is the Difference Between Atrial Flutter and Atrial Fibrillation?

Atrial flutter is a supraventricular arrhythmia with a ventricular rate that is either rapid or variable. With this rhythm, there are multiple atrial contractions for every one ventricular contraction. 

On an ECG, atrial flutter:

Atrial fibrillation occurs due to deterioration in the electrical activity of the atria, resulting in fibrillation. These signals from the atria are then sent to the ventricles in an equally disorganized manner, resulting in irregular ventricular contractions. In atrial fibrillation, there is a rapid heart rate without any regular or predictable rhythm pattern, which is why it is known as an arrhythmia that is irregularly irregular.

On an ECG, atrial fibrillation displays:

Both atrial flutter and atrial fibrillation cause symptoms such as fatigue, heart palpitations, thrombus development, dizziness, and lightheadedness. Atrial fibrillation tends to have wavering or coarse, irregular activity between QRS complexes whereas atrial flutter has more uniform activity.

How To Prepare for Your ACLS Exam

In your role as part of a healthcare team, your colleagues and patients depend on you to be knowledgeable and prepared to lead or assist during urgent or emergent scenarios. To be ready, you want your certification education to offer a challenging and innovative approach to learning so that you are prepared to respond with confidence. In addition, as a healthcare provider with demanding personal and professional schedules, you need the flexibility to obtain, renew, and maintain certifications. You prefer not to coordinate time-off requests, trade shifts, or reschedule patients to complete your certification(s).

American Medical Resource Institute (AMRI) supports healthcare professionals by offering a flexible and convenient learning environment where students can complete their coursework and exam on their schedule, on any device. After completing the online certification program and provider exam, an educator or clinical supervisor at your place of employment facilitates the clinical skills portion of the course conveniently at your workplace — you’ll have everything you need to take your initial or renewal certification course, adjusted to your schedule. AMRI will prepare you for your Basic Life Support (BLS), ACLS, or Pediatric Advanced Life Support (PALS) certification exam(s) so that you are ready when your patients and team need you most. 

If you are searching for practice opportunities or a way to refresh your understanding of ACLS or PALS content, take a quiz to help you apply and test your knowledge. Are you ready to register for an initial or renewal BLS, ALCS, or PALS certification? Register here. We are here for you, so that you can be there for others. 

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