Mine drop and I had a slew of tests. I don't have sleep apnea, but they discovered a PFO. I had a echo cardiologist, which didn't show much. Then they did a Bubble test in another echocarduogram and that showed a right to left shunt. I have turned blue over the years, am always cold, and have Reynauds. I didn't address this early in life and now that we know what's causing it they say I'm too old to repair the hole in my heart.