Brief Answer:
Heart- chest pain on exertion, associated with radiation to left arm.

Detailed Answer:
hello,
The common causes of chest pain,
heart disease, it's usually a exertional pain, pain on heavy activities and subsides with the rest. Associated with pain in left arm, back, neck or jaw. Sometimes heart pain can occur at rest and it suggest patient has a heart attack, it's very severe, associated with sweating, and pain in left arm, jaw etc.
Other is gastritis and reflux disease, this kind of pain more on lying down, after meals, associated with upper abdominal pain, bloating, burping etc.
Pain due to lungs is usually sharp, short lived, increases on deep breathing, associated with cough.
Also pain may be musculoskeletal in origin where pain increases on giving pressure on chest and it's present constantly as a dull ache. Hope that helps you.

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