Effect of simulated dives on diastolic function in healthy men
Jochen Hansel1, Kay Tetzlaff, Detlef Axmann
1Department of Sports Medicine, University of Tuebingen, Silcherstrasse 5, Tübingen, Germany.
European Journal of Applied Physiology
|April 26, 2011
Summary
Simulated dry chamber dives transiently decreased diastolic function, specifically deceleration time, in healthy divers. These cardiac changes suggest factors beyond immersion, cold, or microbubbles may impact scuba diving cardiovascular responses.
Area of Science:
- Cardiovascular Physiology
- Diving Medicine
- Hyperbaric Physiology
Background:
- Scuba diving can cause acute cardiovascular changes due to environmental stressors like immersion and cold.
- Venous gas microbubbles are implicated in right ventricular overload and impaired left ventricular filling post-dive.
Purpose of the Study:
- To investigate cardiac function changes following simulated dry hyperbaric chamber dives.
- To identify potential factors contributing to acute cardiovascular alterations in divers.
Main Methods:
- Twenty healthy male divers underwent two simulated dry hyperbaric chamber dives.
- Echocardiographic assessment of diastolic function (including deceleration time) was performed before and after dives.
- No gas microbubbles were detected during or after decompression.
Main Results:
- A statistically significant decrease in deceleration time was observed 20 minutes post-dive (163 ms to 125 ms).
- Deceleration time tended to return to baseline levels 80 minutes after decompression.
- No significant changes in heart rate, E/A-ratio, or E/e'-ratio were noted.
Conclusions:
- Simulated hyperbaric dry chamber dives induce transient decreases in deceleration time in healthy men.
- Factors other than immersion, cold, or nitrogen microbubbles may contribute to acute cardiac function changes after scuba dives.
