I’m not sure I would go into anxiety about leaving your house since it is likely during your education you will be in contact with patients and have an elevated risk of exposure. If I were to come across this response it would cause me to wonder how the applicant will manage this anxiety during their education as covid-19 will likely continue to be problematic over the next few years. I wonder if you could frame your response is a more proactive way to highlight minimizing risk in light of your heart condition instead of being anxious? Without seeing the prompt or knowing your story it’s hard to offer more specific advice.