Question special

One of the more interesting things I saw in the outcomes was the significant difference in cardiac outcomes. There doesn't seem to be a whole lot of difference between their cardiac disease at baseline, which you mentioned in an answer to Dr. Hurng, but the conservative oxygen group had increased arrhythmia, including new onset atrial fib, and events leading to treatment. The discussion talks about high heart rate leads to worse outcomes, as noted as ref 21. Is the increase in mortality from this study directly related to mainly poor cardiac complications driven by hypoxia?