Is air around the heart dangerous?

there should never be air around your heart. Air should be contained in the lungs. IF you have air in the chest cavity that is outside the lung, you have a pneumothorax and need to see a dr immediately!

The causes of a pneumothorax (air around the heart or lungs) is typically from trauma, such as a puncture wound (knife especially) or gunshot.

If you have a pneumothorax or a pneumo-mediasteinum, you may find itr difficult to breath and that you heart rate may increase due to the increased pressure on both your heart and lungs.

Air can be removed using a special syringe, allowing the lungs to expand normally and reducing the pressure on the heart.

If you have these symptoms you should go to the emergency room immediately