If you stretch patent leather it will wrinkle and the wrinkles will be very noticeable. You don't explain if you want to use a shoe stretcher or if you want to know if your shoes will stretch as you wear them so I'm assuming is the first one. After all the money I've spent on shoes I learned that I have to go for comfort first unless I want the shoes to live in my closet. Since you mentioned your shoes are patent leather and not PVC then they will stretch a bit, but not as regular leather. I'd say that no matter how beautiful they are if you're not comfortable get half a size bigger or return them.