Clear cut pass here for me, and it isn't close. 1) This auction is live, with LHO showing a strong NT, and whilst RHO may not have much, he may well have a raise to 3NT with 4 hearts. 2) You are vulnerable against not. You also have a full 7 losers, with potential for more than that. The auction has not given us any suggestion that partner will be able to cover those losers. This vulnerability would tend to make them double you on any excuse, and frequently on no excuse.