There are 5 basic causes of dyspnoea
We need to look at all these in turn to find the cause, starting with the most likely.
With the lungs Xray, spirometry (pre and post bronchodilator) and a CT chest would be the starting point.
For the heart and ECG will show rhythm problems and old heart attacks, enzymes are useless in this context as they are only elevated when you have a heart attack for a maximum of 1 week. We do see them elevated with myocarditis (infection/inflammation of the heart) but this is rare. What you need is an echocardiogram (Ultrasound of the heart) to assess valve and muscle function as well as pulmonary pressures.
A full blood count will show anaemia and other blood cell problems. The CMP will look at liver and kidneys.
Musculoskeletal problems are assessed clinically
Neurological things are rare and last on the list.
Here is what the Mayo Clinic has to say about it: www.mayoclinic.org/symptoms/shortness-of...inition/sym-20050890