@shels93, You’re most certainly not a hypochondriac. You saw the urgency in your husband’s condition and it’s commendable you reached out to his cardiologist right away. As a wife, I know sometimes it takes Herculean effort to get our guys to head for the doctor. They tend to ‘just tough it out’…so, good for you. 🙂

Myelodysplastic syndromes (MDS) are a group of blood disorders characterized by abnormal development of blood cells within the bone marrow. There are several types of MDS so your husband’s hematologist will help to narrow down his specific type so that he can begin some treatments to slow the progression.
I’ve provided the Mayo Clinic’s informational page on MDS just to help inform you a little more about the disease. From experience, I know that reading some of the information can sound a little daunting. Not everything you read will apply to your husband but this will give you a little overview until you meet with his doctor.
https://www.mayoclinic.org/diseases-conditions/myelodysplastic-syndrome/symptoms-causes/syc-20366977
You husband will most likely have a few more blood tests and possibly a bone marrow biopsy coming up to help get a more exact diagnosis.
It can be tough when first diagnosed to even know what to ask the doctor. Since I’m expecting this will be his (and your) first visit with the hematologist, I thought I’d give you a link to some conversations about How to get off to the best start with a new specialist.

Your Tips on How to Get Off to the Best Start with a New Specialist: https://connect.mayoclinic.org/discussion/your-tips-on-how-to-get-off-to-the-best-start-with-a-new-specialist/

How’s your husband feeling about all of this?