Rick Matros sounded irritated. The chief executive of Sabra Health Care REIT Inc., a publicly-traded real estate investment trust, had spent much of this Q2 earnings call in August discussing a single troubled property: the Frisco outpost of the Dallas-based Forest Park Medical Center luxury hospital chain, whose operators hadn't paid Sabra any rent in eight months. As an anchor of the fast-growing suburb's shiny Frisco Square development, the hospital occupies one of North Texas' most enviable commercial addresses. Millions of dollars were spent adding spa-like touches throughout, in an effort to decrease patient anxiety before surgery.