POTS syndrome. (postural orthostatic tachycardia syndrome)
if he gets tachycardia and dizziness upon standing it could definitely be POTS, however pretty rare because POTS is already a very rare syndrome, and the majority of people who get it are teenage girls.
however it’s not impossible.
i would look it up on google.

It could just be stress but it could also be a very serious cardiac condition. I would recommend calling and ambulance and getting to a hospital ASAP. Some possible conditions could be Angina, Myocardial infarction (heart attack) or myocardial ischemia.

The heart rate is elevated especially at a resting state, but some factors to apply. (age, weight, genetics, smoking etc)Scine I obviously don’t know your husband its tough to tell.

The shortness of breath in addition to the elevated vitals is a pretty serious things and should be taken care of right away regardless of what his boss might think.

He should not be in the 120’s if his resting heart rate is an athletic 55!!!

Difficulty breathing (shortness) is a condition that is always serious (especially along with the other problems).

It could be anything from as harmless as an anxiety attack, to something as serious as malignant hypertension, to cardiac problems (I doubt it would be a massive myocardial infarction, since that usually is severe and irreversable during the first hour max). But he can still have a “milder” attack or angina (a forerunner for a massive attack).

He should get checked as soon as possible, even perhaps call 911 from his workplace ;-P
His boss must be a complete imbecille to not take this serious!

need to get checked ASAP!! might be having a stroke

Call 911 for him. This is a medical emergency. He can get another job, not another life

STRESS!!!