A heart attack is a severe medical emergency where blood flow to the heart muscle becomes blocked, leading to tissue damage. While many people associate heart attacks with chest pain, a common and often confusing symptom is pain felt in the arm. This phenomenon, where pain originating in one part of the body is felt in another, can be puzzling.
Understanding Referred Pain
Referred pain occurs when the brain misinterprets pain signals. Pain signals from internal organs travel along nerve pathways that converge with nerve pathways from other parts of the body, such as the skin or limbs. The brain, accustomed to signals from these external areas, projects the pain there, making it challenging to pinpoint the true source.
For example, pain from gallstones might be felt in the shoulder blade, or a “brain freeze” from consuming cold food quickly is felt in the head, even though the cold stimulus is in the mouth or throat. This means the pain is real, but its perceived location is incorrect due to shared neural wiring in the nervous system. Researchers continue to investigate the exact mechanisms behind why the brain sometimes misdirects these pain signals.
The Nerve Connection Between Heart and Arm
The reason a heart attack can cause arm pain lies in the shared nerve pathways between the heart and the arm. Nerves carrying pain signals from the heart enter the spinal cord at similar levels as nerves from the arm.
When the heart muscle lacks oxygen during a heart attack, chemicals are released, activating pain receptors. Because the brain receives these signals through pathways also used by nerves from the arm, it can become confused, interpreting the heart pain as originating from the arm. This often results in pain felt on the ventral and medial surfaces of the arm and forearm, sometimes extending to the little and ring fingers. While the pain is most commonly felt in the left arm, it can also affect the right arm or both.
Recognizing Other Heart Attack Symptoms
While arm pain is a recognized symptom, be aware of other common signs of a heart attack. The most frequent symptom is chest pain or discomfort, often described as a heavy, crushing, or squeezing sensation. This chest discomfort may last for more than a few minutes or may go away and return.
Other symptoms include:
- Shortness of breath, which may occur with or without chest discomfort.
- Nausea, vomiting, lightheadedness, and dizziness.
- Cold sweats.
- Pain radiating to the jaw, neck, upper back, or stomach.
Symptoms can vary, with women more likely to experience atypical symptoms such as unusual fatigue, indigestion, or pain in the back, shoulders, neck, or abdomen, sometimes without significant chest pain.
Immediate Action and Seeking Help
Immediate action is crucial if you or someone experiences symptoms suggesting a heart attack, including arm pain. Call emergency services (e.g., 911 in the US) without delay. Prompt medical attention can significantly reduce heart muscle damage and increase the chance of survival.
While waiting for emergency help to arrive, have the person sit down, rest, and remain calm. Loosen any tight clothing to aid comfort. If they have a nitroglycerin prescription, they may take it as directed, but calling emergency services is always the first step. Do not drive yourself to the hospital unless there is no other option.