Do Humans With a Patent Foramen Ovale Have a Higher Core Body Temperature During Rest, Exercise and Post‐Exercise?

Approximately 25–40% of the population has a patent foramen ovale (PFO). We have shown that people with a PFO (PFO+) have decreased pulmonary gas efficiency at rest due to a widened AaDO 2 . We have also shown that during maximal exercise, PFO+ subjects exhibited a lower S a O 2 than subjects without a PFO (PFO−), which was caused by an increased esophageal temperature (T esoph ), resulting in a right shift in the oxyhemoglobin dissociation curve. It is unknown if this was coincidental or if PFO+ subjects have a higher T esoph Therefore, the purpose of this study was to determine if PFO+ subjects have a higher T esoph than PFO− subjects during rest, exercise and post‐exercise. Six males (3 PFO−: age ‐ 23 ± 1 yrs, height – 177.0 ± 7.4 cm, weight – 79.0 ± 5.9 kg, BSA ‐ 1.97 ± 0.11 m 2 ; 3 PFO+: age ‐ 24 ± 4 yrs, height – 177.0 ± 2.9 cm, weight – 82.5 ± 4.7 kg, BSA 2.01 ± 0.05 m 2 ) completed exercise bouts on two separate days. On day 1, subjects completed a VO 2MAX test; during day 2 they completed an exercise bout with four 2:30 min. stages at 25, 50, 75 and 90% of the maximum workload achieved during the VO 2MAX test. We measured T esoph , rectal temperature (T rectal ) and intestinal temperature (T pill ). There were no temperature differences detected between groups for any exercise protocols. These data suggest that there is no difference in T esoph between PFO+ and PFO− subjects.