Back pain is usually caused by musculoskeletal issues like muscle strain or disc problems. However, on rare occasions, it signals a serious underlying cardiac condition. Heart problems can manifest as pain far from the chest, including the back, neck, jaw, or arms. Understanding the mechanism that causes this misdirected sensation is important for recognizing when back pain signals a potentially life-threatening event.
The Mechanism of Referred Pain
The phenomenon where a heart problem causes pain in the back is known as referred pain, which is the brain’s misinterpretation of a signal’s origin. The heart and the upper back share nerve pathways that converge at the spinal cord, specifically the thoracic segments T1 through T5. Pain signals originating from the heart travel along visceral afferent nerve fibers.
These signals enter the spinal cord at the same levels as the somatic nerves that collect sensations from the skin, muscles, and tissues of the chest and upper back. Because the brain is accustomed to receiving pain input from the body’s surface, it mistakenly attributes the internal pain signal to a peripheral location like the back. This convergence of sensory input onto shared neurons in the spinal cord explains why heart pain is perceived elsewhere. Vagal afferent fibers may also play a role in this atypical pain referral, particularly to the neck and jaw.
Specific Cardiac Conditions That Cause Back Pain
Several serious heart and vascular conditions can cause referred back pain. The location and nature of this pain can offer clues to the underlying problem. One recognized cause is a myocardial infarction, commonly known as a heart attack. While chest discomfort is the most frequent symptom, back pain, particularly in the upper back, is an atypical presentation. Back pain is more common in women experiencing a heart attack than in men, often presenting alongside non-chest symptoms like nausea, dizziness, and fatigue.
Angina, which is chest pain caused by reduced blood flow to the heart muscle, can also radiate to the back, jaw, or arms. Stable angina pain typically occurs with exertion or stress and resolves quickly with rest or medication. Unstable angina, a more serious condition, may present with pain that is new, worsening, or occurs at rest, and this discomfort can also be felt in the back.
A less frequent but catastrophic cause of severe back pain is an aortic dissection, which involves a tear in the inner layer of the aorta, the body’s main artery. The pain is often described as sudden, severe, and “tearing” or “ripping.” This intense pain is often located in the upper or mid-back, specifically the interscapular region (between the shoulder blades). This type of back pain is maximal from the moment of onset and warrants immediate emergency medical attention.
Key Differences: Cardiac vs. Musculoskeletal Back Pain
Differentiating between cardiac and common musculoskeletal back pain involves assessing the nature of the pain and the factors that trigger or relieve it. Musculoskeletal pain, which arises from muscles, ligaments, or spinal joints, is typically sharp, localized, or shooting. This pain is usually aggravated by specific movements, such as bending, twisting, or lifting, and is often relieved by changing position or resting. The area of discomfort may also be tender to the touch.
In contrast, back pain originating from the heart is often described as a pressure, tightness, or a dull, deep ache. This cardiac pain does not change with shifts in body position, movement, or deep breathing. Cardiac pain can be triggered by physical exertion or emotional stress and is often accompanied by other systemic symptoms. The back pain of a heart attack is generally persistent and worsening, whereas angina-related back pain is transient, lasting only a few minutes before resolving with rest.
The location of the pain can also provide a clue. Cardiac referred pain often concentrates in the upper back or between the shoulder blades, rather than the lower back, which is the site of most common muscle strains. The pain from an aortic dissection is often in the mid-back and is characterized by its sudden, excruciating intensity. Any uncertainty about the cause of back pain, especially when accompanied by other symptoms, requires professional medical evaluation.
Warning Signs and When to Seek Help
Any back pain suspected to be cardiac in origin requires immediate professional assessment due to the potential for a life-threatening event. An immediate call for emergency medical services is necessary if back pain presents with a sudden, severe, and tearing sensation, particularly in the upper or mid-back, as this is the classic sign of an aortic dissection.
Emergency care is warranted if back pain, even if dull or pressure-like, is accompanied by other common symptoms of a heart attack. These warning signs include:
- Shortness of breath.
- A cold sweat.
- Dizziness or lightheadedness.
- Nausea.
Pain that spreads to the jaw, neck, shoulder, or one or both arms alongside back discomfort should also raise immediate concern. Back pain that begins or worsens with physical activity and does not resolve quickly upon resting may signal a heart condition.