Please choose the correct ending to complete the given sentence: Health: [header] How to diagnose mitral stenosis [title] Watch for shortness of breath. [step] One of the main symptoms that mitral stenosis may present with is shortness of breath-in particular, waking in the night with breathing difficulties. The shortness of breath may get worse with exertion, and/or when lying down.

Ending1: If your breathing is accompanied by shallow breaths, this may be a sign of mitral stenosis. Be aware that more serious complications related to mitral stenosis will require heart surgery and/or other surgical intervention. Ending2: [substeps] If you notice the shortness of breath, don't panic. Get up and go to the bathroom to clean yourself. Ending3: The shortness of breath is caused by decreased effectiveness of blood flow with each heartbeat, due to partial blockage of the mitral valve (called " stenosis "). [substeps] Your shortness of breath may progressively get worse with time. Ending4: If you feel like you have an obstruction blocking your airways, blood then may be in your lungs. Other symptoms such as shortness of breath, dizziness, or lightheadedness may also signal mitral stenosis.

Answer format: ending1/ending2/ending3/ending4