The first step should be for you and your doctor to request consultation with a lung specialist (Pulmonologist) to determine with reasonable certainty that the primary cause of your shortness of breath is the paralyzed left hemi-diaphragm. (UDP) It is a bit unusual for a well conditioned person to experience such a high degree of dyspnea on the basis malfunction of one hemi-diaphragm so it will be most important to determine that your lung function is otherwise normal and your cardiac function normal as well. It is also important to keep in mind that such paralysis can spontaneously resolve, after a year or more, partially or completely. In addition over time many individuals adapt or physiologically compensate in response to UDP, to the point where it becomes less physically limiting .
Effective surgical intervention, called diaphragmatic plication, is an option and can be done with the use of minimally invasive techniques. Electrical pacing of one’s diaphragm is a seldom used option but should only be performed at centers with specialized expertise, after other means have failed.