| Question | Probable Pathophysiology |
|---|---|
| Associated only with exertion? | Heart failure, restrictive or obstructive lung disease |
| Associated with exertion and occurs at night? Cough and wheeze? | Asthma or heart failure |
| Associated with exertion, chest, arm or neck discomfort and concurrent nausea or diaphoresis? |
Angina pectoris |
| Worse when assuming upright position? | Liver disease with arteriovenous shunts at the lung bases (platypnea) |
| Present in the lateral decubitus position? | Unilateral lung or pleural disease (trepopnea) |
| Fast onset when supine, relieved by lateral or upright positioning? |
Bilateral phrenic nerve dysfunction |
| Occurring within minutes or hours of becoming recumbent? | Heart failure (orthopnea) |