Left shoulder pain can be an alarming symptom, often prompting concerns about a heart attack. This article clarifies the connection between left shoulder pain and heart attacks, differentiates it from other causes, and guides individuals on when to seek urgent medical attention.
How Heart Attacks Cause Left Shoulder Pain
A heart attack occurs when blood flow to part of the heart muscle is blocked, typically by a clot. This oxygen deprivation damages heart tissue, causing pain that can spread beyond the chest. This is due to “referred pain,” where nerves from the heart and left shoulder share pathways in the spinal cord. The brain misinterprets the pain’s origin as the shoulder or arm, rather than the heart.
Heart attack-related shoulder pain is often described as a heavy, crushing, or squeezing sensation, or a dull ache. This pain frequently radiates from the chest to the left shoulder, arm, neck, jaw, or back. It may intensify with physical activity or emotional stress, and unlike musculoskeletal pain, it does not subside with rest or position changes. It is often accompanied by other symptoms, including chest discomfort, shortness of breath, nausea, lightheadedness, dizziness, and cold sweats.
Common Non-Cardiac Causes of Left Shoulder Pain
Left shoulder pain most often originates from non-cardiac issues, frequently involving the musculoskeletal system. Common causes include rotator cuff injuries like tendinitis or tears, which involve inflammation or damage to shoulder tendons. Arthritis, including osteoarthritis and rheumatoid arthritis, can also lead to pain and stiffness. Bursitis, inflammation of fluid-filled sacs cushioning joints, and muscle strains from overuse or injury are also common.
A “frozen shoulder” (adhesive capsulitis) causes stiffness and pain from thickening of the shoulder joint capsule. A dislocated shoulder or shoulder impingement, where soft tissues get trapped under shoulder bones, can also cause significant pain.
Nerve issues, such as cervical radiculopathy (a pinched nerve in the neck), can cause pain, tingling, or numbness radiating from the neck to the shoulder and arm. Internal organ conditions can also refer pain to the left shoulder. Digestive issues like gallstones, pancreatitis, peptic ulcers, gastritis, or irritable bowel syndrome (IBS) can cause referred shoulder pain due to shared nerve pathways. Less commonly, lung conditions like pneumonia or a pulmonary embolism may also cause shoulder discomfort.
Key Differences Between Heart-Related and Other Shoulder Pain
Distinguishing cardiac-related shoulder pain from other causes involves several characteristics. Heart attack pain often has a sudden onset and is persistent, not easing with rest or position changes. Musculoskeletal pain often has a gradual onset, is aggravated by specific movements or pressure, and may improve with rest, ice, or anti-inflammatory medications. For instance, muscle strain pain worsens when lifting the arm, while cardiac pain typically does not change with such movement.
The nature of the pain also differs. Cardiac pain is typically a deep, diffuse pressure, squeezing, or heaviness across the chest that can spread to the shoulder. It is rarely sharp or localized. Non-cardiac shoulder pain, especially from musculoskeletal injuries, is often sharp, stabbing, or aching, and can be pinpointed. Nerve impingement pain may present as a sharp, burning sensation with tingling or numbness.
Accompanying symptoms are a key differentiator. Cardiac-related shoulder pain is typically accompanied by other symptoms like chest discomfort, shortness of breath, sweating, nausea, lightheadedness, or anxiety. If shoulder pain occurs in isolation without these additional symptoms, it is less likely heart-related. Musculoskeletal causes do not present with these systemic symptoms, focusing on localized pain and possibly limited range of motion.
When to Seek Emergency Care
Prompt medical attention is important when left shoulder pain raises concern for a heart attack. If the pain is new or worsening and accompanied by chest discomfort like pressure, squeezing, or fullness, immediate emergency care is necessary. Other accompanying symptoms requiring an emergency call include shortness of breath, nausea, vomiting, dizziness, lightheadedness, or a cold sweat. These symptom combinations strongly indicate a potential cardiac event.
Seek urgent medical help if left shoulder pain comes on suddenly and is intense, especially without a clear cause or injury. Do not drive yourself or others with these symptoms; call emergency services immediately. Emergency medical personnel can initiate treatment en route, significantly improving outcomes. Even with mild or atypical symptoms, seeking medical advice is prudent, particularly for those with heart disease risk factors.