Relatively little known hazard linked to open water swimming explored

Fluid on the lungs, or pulmonary oedema as it's formally known, is a relatively little known hazard associated with open water swimming, warn doctors in the journal BMJ Case Reports after treating a woman with the condition. Older age, swimming long distances, cold water, and female sex are among the risk factors, as are high blood pressure and pre-existing heart disease. But it frequently occurs in those who are otherwise fit and healthy, highlight the authors.

The woman in question was in her 50s and a keen competitive long distance swimmer and triathlete. Otherwise fit and well, she was struggling to breathe and coughing up blood after taking part in an open water swimming event at night in water temperatures of around 17°C while wearing a wetsuit. Her symptoms started after swimming 300 metres. On arrival at hospital, her heartbeat was rapid, and a chest x-ray revealed pulmonary oedema. Further scans revealed that fluid had infiltrated the heart muscle, a sign of strain known as myocardial oedema. But she had no structural heart disease.