I can't say for sure, but going from my interpretation of what seems to be the (sunni) scholarly consensus, it really shouldn't matter. Pork is not allowed to be eaten for a few reasons, none of them are relevant for cardiac valves especially considering you don't ever "consume" the pork. Pork is only allowed if you don't have another alternative when it comes to feeding yourself,but since I don't think it's restricted at all for most other uses, there's no need to even have to chose an alternative if possible. Though there is definitely a cultural repulsion towards anything related to Pork in Islamic countries so I'd definitely expect alternatives to be more popular based on that repulsion/taboo even if it's not haram