I will certainly be praying for you and your husband - I know this must be a very frightening situation - I will be praying that everything goes well.
Heart disease can cause extreme fatigue and shortness of breath, because when the arteries get clogged or blocked, there is less blood flow to the organs and tissues. The arteries are the blood vessels that carry oxygen-containing blood from the heart to the head and body. The body needs oxygen to function, and when your heart isn't functioning right, the blood may not get enough oxygen in it, or the blood can't get through the blocked arteries to carry the oxygen to the internal organs. The carotid arteries are the big arteries on each side of the neck that carry blood to the front part of the brain. You can feel your carotid arteries by feeling the pulse on your lower neck, on either side of your windpipe. Just like the coronary arteries (the arteries in the heart itself), the carotid arteries can develop atherosclerosis, the build-up of fat and cholesterol deposits, called plaque, on the inside of the arteries. Over time, the build up of these deposits makes the arteries get narrower, letting less blood through. In the carotid arteries, this decrease the blood flow to the brain - in the coronary arteries, it decreases the blood flow to the heart.
There are several procedures that can be done, depending on how severe the blockage is. A severe blockage in several arteries might require open-heart surgery, but if the blockage isn't as bad, then a procedure called angioplasty might be availaable. But the doctors will have to do a lot of tests to find out exactly where the blockages are and decide the best way to treat them. It's really important to make sure the doctors know all the medicines your husband is taking, so if you don't have a list, take the actual medicines with you. Be sure to include any over the counter medicines, vitamins, herbs or supplements - everything Larry is taking. And if your husband has taken steroids (medicines like prednisone, solu-medrol, deltasone, etc.) in the last year, be sure the doctors know about that too.
I will be keeping you and Larry both in my prayers today and tomorrow. Please let us know how it goes!