M.P.
My mother had 3 surgeries to replace her mitral valve. Her first was when she was in her late 60's, I think. She was 80 when she had her last surgery. She came thru the surgeries just fine. There was a big difference in the length of time it took her to recover between the first and the second. Much better with the second. The procedure is probably even better now, 20 some years later.
Yes, the surgery was scary for all of us. First time I'd experienced anything so serious. But she came thru it just fine and had several years feeling better than she had in years.
Is it a trans esophogeal cardio echogram? It's similar to an ultrasound, I think. Again, it's done under anesthetic. I think probably twilight. Anesthetics are really good now. It is not life threatening. Last time I had anesthesia I woke up feeling so good I was sure I hadn't had surgery yet.
Another way that they look at the heart is by passing a catheter thru a vein found in the groin or the wrist. My mother's procedure was thru the groin. She had to stay in the hospital so that they could watch for bleeding. Mine was thru the wrist. Mine was a piece of cake. It was out patient and I had no difficulties afterward. Neither process is life threatening.
There are always risks with surgery. I am guessing the risks are greater when one is 80. Talk with the cardiologist and have him explain everything. I had surgery for lung cancer and the surgeon talked to me and a friend taking us thru the procedure step by step. Ask your FIL's doctor to talk with you. My mother's doctors talked to all of us anytime we had a question or concern. Shouldn't matter that he's a FIL, as long as he gives the doctor permission to do so.