Is Endurance Exercise Safe? The Myth of Pheidippides.

With the increase in participation in endurance events in the general population, patient concern may arise as to whether endurance exercise is safe. Acute but not chronic increases in blood urea nitrogen, creatinine, and urine albumin occur in endurance exercise. Iron-deficiency anemia may be observed in female athletes.

Hypoxemia without persistent right-to-left pressure gradient across a patent foramen ovale: A clinical challenge.

Patent foramen ovale (PFO) closure for systemic hypoxemia is controversial. The first systematic, albeit retrospective, study was recently presented which showed good procedural and clinical success for PFO closure for this indication. We present a case of acute right to left intra-cardiac shunt across PFO where the shunting is not persistent.