Atrial flutter (AFL) is an abnormal heart rhythm, or arrhythmia, where the upper chambers of the heart (the atria) beat at an unusually rapid rate. This condition is caused by a faulty electrical short circuit, usually within the right atrium, that creates a fast, organized signal. The rapid electrical activity prevents the atria from contracting fully and efficiently. This inefficiency leads to noticeable symptoms, differing significantly from a normal resting heart rate of 60 to 100 beats per minute.
The Specific Feeling of Palpitations
The most direct symptom of atrial flutter is the sensation of palpitations, which is the awareness of the heart beating. This feeling is often described as a distinct fluttering or quivering sensation deep within the chest. Unlike the chaotic, irregular beating associated with atrial fibrillation, atrial flutter often presents as a rapid, yet regular, heart rhythm.
This rapid rhythm occurs because the atria are electrically stimulated at a very high rate, often between 250 and 350 beats per minute. Although the lower chambers (ventricles) cannot keep up with this pace, they still beat much faster than normal, commonly reaching rates of 150 beats per minute or more. This is felt as a racing or pounding heart, sometimes described as machine-like due to its rapid, organized pattern.
The perception of this rapid heart action is not always confined to the chest cavity. The rapid atrial contractions can sometimes cause a throbbing or pulsing sensation in the neck or throat. This feeling is distinct from a normal pulse and is a direct result of the upper heart chambers beating so quickly.
How the Body Reacts to Atrial Flutter
The fast heart rate significantly reduces the heart’s pumping efficiency, triggering systemic reactions throughout the body. When the heart beats too quickly, the ventricles do not have enough time to completely fill with blood before contracting. This reduction in cardiac output decreases the amount of oxygenated blood pumped, causing symptoms felt outside the chest.
A common systemic reaction is profound fatigue, even without exertion. Since the body’s tissues are not receiving an adequate supply of oxygen and nutrients, a general sense of weakness or lack of energy can set in. Diminished blood flow to the brain can also manifest as lightheadedness or dizziness.
In more pronounced episodes, the lack of sufficient blood pressure and oxygen delivery can lead to shortness of breath (dyspnea). This occurs as the body attempts to compensate for poor circulation by increasing the rate of breathing. In rare or prolonged cases, severely reduced blood flow and rapid rate can lead to fainting (syncope) or a sensation of near-fainting. Some individuals may also experience tightness or pain in the chest, known as angina, because the heart muscle is not receiving enough oxygen to support its rapid workload.
What to Do When Symptoms Occur
If an individual experiences palpitations accompanied by other systemic symptoms, it is advisable to consult with a healthcare provider. A doctor can evaluate the symptoms and determine if they are related to atrial flutter or another condition. Tracking the frequency and duration of these episodes is helpful, as this information assists in diagnosis.
Certain symptoms require immediate medical attention and should prompt a call to emergency services. Emergency care is necessary if the rapid heart rate is accompanied by severe chest pain, significant difficulty breathing, or a feeling of losing consciousness. These severe symptoms may indicate that the heart is struggling to maintain adequate blood flow or that a serious complication has developed.