SAN FRANCISCO — The annual meeting known as Transcatheter Cardiovascular Therapeutics typically features some interesting but not unpredictable developments, a statement that applies to this year's edition as well . . . for the most part. There is of course the not-unexpected continuation of uneven evidence for PFO closure and news of a TAVR competitor for Edwards Lifesciences (Irvine, California) and Medtronic (Minneapolis), but the strangest noise is just a noise, although it's about the most obnoxious noise heard since the invention of techno.