I would argue that a site like this is actually 'self-vetting'. It is our responsibility as designers on this site to directly address work we suspect as copyright infringement (see faqs). And what a resource: a pool of designers from all over the world.
As for the removed logos, they are similar to the Southwest Cardio Associates logo but not necessarily derivative. For instance, the fingers are different, putting letters in the heart is different, and it's a different industry (which should count for something). I've seen the heart-hands in tv ads, in medical brochures, and I even created a Valentine's Day card years ago by scanning my hands making a heart. It seems the heart-hands sign is a popular device, perhaps cliche. For instance, searching 'heart hands' on istockphoto.com yields many similar results.