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

Abstract

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 AaDO2. We have also shown that during maximal exercise, PFO+ subjects exhibited a lower SaO2 than subjects without a PFO (PFO−), which was caused by an increased esophageal temperature (Tesoph), resulting in a right shift in the oxyhemoglobin dissociation curve. It is unknown if this was coincidental or if PFO+ subjects have a higher Tesoph Therefore, the purpose of this study was to determine if PFO+ subjects have a higher Tesoph 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 m2; 3 PFO+: age ‐ 24 ± 4 yrs, height – 177.0 ± 2.9 cm, weight – 82.5 ± 4.7 kg, BSA 2.01 ± 0.05 m2) completed exercise bouts on two separate days. On day 1, subjects completed a VO2MAX 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 VO2MAX test. We measured Tesoph, rectal temperature (Trectal) and intestinal temperature (Tpill). There were no temperature differences detected between groups for any exercise protocols. These data suggest that there is no difference in Tesoph between PFO+ and PFO− subjects.