A sensation of discomfort, numbness, or pain in the arm is a recognized warning sign that can precede or accompany a heart attack. While many people associate a heart attack only with crushing chest pain, symptoms often manifest in other areas of the body, making it important to recognize these less obvious signals. The pain felt in the arm is not a problem with the arm itself but a complex signal originating in the heart that the brain misinterprets. Recognizing this symptom can significantly reduce the time taken to seek medical attention, which directly impacts the chance of survival.
Why Heart Pain Travels to the Arm
The phenomenon that causes heart pain to appear in the arm or other distant body parts is called referred pain. This occurs because the nerves carrying pain signals from the heart share pathways with nerves that serve the arm, shoulder, and jaw. During embryonic development, these distinct structures develop from nerve tissues that arise from the same spinal cord segments.
When the heart muscle is damaged due to a lack of oxygen during a heart attack, its sensory nerves are stimulated. These nerve fibers travel back to the spinal cord and enter at the same level as the sensory nerves coming from the arm and other upper body areas. The brain’s sensory cortex receives a confused signal, as it is not highly specialized for processing signals from internal organs. It assumes the strong pain signal is coming from the more familiar, superficial body location, such as the arm, rather than the heart itself.
Identifying Arm Discomfort During a Heart Attack
The question of which arm goes numb most frequently points to the left side of the body, as pain radiating to the left arm remains the most common presentation of cardiac ischemia. However, it is a misconception that only the left arm is affected, as discomfort can also occur in both arms or solely in the right arm. Some research suggests that pain radiating to both arms or only the right arm may indicate an increased likelihood of acute myocardial infarction.
The sensation is rarely described as a sharp, localized pain. Instead, it typically presents as a diffuse feeling of pressure, aching, or heaviness. Patients often report numbness, tightness, or a tingling sensation that travels down the arm from the shoulder. Any unexplained discomfort in the arm that is new, unusual, or accompanied by other symptoms should be treated with immediate suspicion.
Accompanying Symptoms and Sex Differences
Arm discomfort is rarely an isolated symptom during a heart attack; it usually occurs alongside a broader pattern of physical distress. The most common accompanying symptom is discomfort in the center of the chest, often described as pressure, squeezing, or fullness. Other classic signs include shortness of breath, breaking out in a cold sweat, nausea, and lightheadedness. Intense anxiety can also be a symptom.
Heart attack symptoms can present differently between sexes. While men often experience typical symptoms like chest and left arm pain, women are more likely to experience “atypical” symptoms without the classic crushing chest pain. These differences can include unusual or unexplained fatigue lasting for several days, back pain, or jaw pain.
Women frequently report symptoms such as nausea, vomiting, or what feels like indigestion, which can lead to a delay in seeking emergency care. They may also experience pain that travels to the upper back, shoulder blades, or the right arm, rather than the expected left arm. Recognizing these variations helps prevent misdiagnosis and ensures prompt treatment for all patients.
When to Seek Emergency Medical Help
A heart attack is a time-sensitive medical emergency. If you or someone near you experiences arm discomfort, numbness, or any combination of the discussed symptoms, call the local emergency number, such as 911, right away. Do not attempt to drive yourself or the affected person to the hospital, as emergency medical services (EMS) personnel are equipped to begin life-saving treatment en route.
While waiting for EMS to arrive, the individual should sit or lie down and try to remain calm. If the person is conscious, not allergic to aspirin, and has no medical reason not to take it, an adult dose of 325 mg of chewable aspirin can be administered to help prevent further blood clotting. Treatment to restore blood flow to the heart is most effective when administered within the first hour of symptom onset.