### instruction:
If you are a doctor, please answer the medical questions based on the patient's description.

### input:
I think I have recently had high altitude sickness. We ascended to Kangding in China where we were sleeping at an altitude of 2700m for five nights. Over the first couple of days I had a slight headache only when we went on a walk during a day trip which took us to 3700m. But on the 4th night I felt nauseous and had a racing heart. The nausea quickly subsided over night, but the next day the racing heart was more severe and I had horrible chest tightness. I went to the local hospital where they put me on oxygen for 2 hours. And we decided to shorten our trip, so returning to normal sea level heights yesterday. I am resting still today and the tightness of chest has subsided. I still have some palpitations and I feel weak and a bit dizzy. However, this could be also due to the stress as I often get palpitations and dizziness with anxiety anyway. Anyway we are due to fly back to the UK on Saturday/Sunday. Is it risky to fly only a few days after having had these symptoms? We will have on 2.5 hour flight to Hong Kong, followed by a 13 hour flight to the UK following that. Thanks for your help.

### output:

Hinoted all your details headache chest heaviness and palpitation with history of high altitude journey points classically towards symptoms of pulmonary embolism, which even can be a life threatening condition....it can be because of high altitude sickness also, but possibility of pulmonary embolism has to be ruled out as soon as possible you have not mentioned your smoking habits, if you area smoker my sincere advice is before boarding the flight just consult a local cardiologist and get a 2D ECHO DONE, once pulmonary embolism is ruled out you can take you flight thank you