That type of chest discomfort can be cardiac vasospasms or even esophageal spasms. Have you had GI manometry to rule out the esophageal spasms? The treatment is basically the same for either...nitro if episodes are not frequent and long acting nitrates or calcium channel blockers for those with more frequent problems.

What "visible" damage have they caused and how is your doctor treating this?

They are a part of autonomic neuropathy, so you may have periodic problems when other AN issues arise. However, the treatments can relieve your chest pain.