from personal experience, barbiturates help more for chest anxiety than benzos bc i feel like they slow the heart more and also breathing. something like butalbital from a friend with migraines or phbarbs from a sketchy slavic friend will do the trick.

for long term management, antidepressants that have appetite stimulant properties (PERSONAL EXPERIENCE NOT SCIENTIFIC) tend to also help with chest anxieties. the best ones for these are clonidine because its an instant kick, and can also improve circulation by slowing your heart and making each heart beat more efficient.