Breathlessness is a subjective sensation rather than an actual one. The patient reports difficulty breathing, but not all breathlessness is related to actual problems in the lungs or airways. In angina, breathlessness is the product of many complex mechanisms related to defective heart filling with blood secondary to its ischemia. It is exertional just like the pain and relieved by rest. Breathlessness may also be accompanied by rapid breathing and can be a result of the panic attack accompanying angina.