It is syphilis. Syphilis is an endarteritis! :)
“The pathologic changes associated with syphilis are characterized by obliterative endarteritis that is found in all stages of the disease.”https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2811633/
I choose MVP too, but this patient’s main symptom is cough only during exercise. This is more indicative of exercised associated asthma. You could see shortness of breath in MVP during exercise, but choosing MVP leaves the cough unaccounted for.