Is there a 40 percent chance of dying from covid if you have severe mitral valve regurgitation? patients with covid-19 and severe valvular heart disease have poor clinical outcomes with mortality approaching 50% within 30 days of hospital admission?

I don't know what the percentages are,.but presence of cardiovascular disease raises mortality rates. You should take strong precautions like getting all your booster shots, mask when around a lot of people, avoid crowds. Ask your spouse to do the same.

If you have to be hospitalized looks like 50% chance. Please mask and get your vaccinations for both COVID and flu.