About DVT:
   DVT(deep vein thrombosis) is also known colloquially as ECS (economiccabinsyndrome).
    When the passenger has sit motionlessly in a cramped seat in the economy class on the airplane for a long time, the blood circulation of the leg vein becomes slow and the blood coagulates which causes the blood in the lower limbs to curdle and forms the blood clot (“thrombus”). After they leave the airplane and have some activities, the thrombus falls off and travels through the right ventricle of the heart and to the pulmonary artery causing a pulmonary embolism which makes the blood difficult to be aerated in the lung and causes the breathing problem, chest pain and emptysis.
But the passenger in the first class on the long-haul flight, on the short-range flight and the long-distance bus, and even the trucker also may be affected with ECS. For DVT, the thrombosis of travel probably is a more felicitous name, because the result of researches shows that it is very common during travel.
   How to prevent ECS? The specialists have pointed out that the elder, those women who are taking contraceptive pills containing oestrogen, and persons who are obese or just had an operation, are the ones most at risk for ECS. In order to prevent ECS, the best measure considered to take is widening the distance between the two seats. But out of consideration of the profit, I am afraid that the airline companies won’t do that. So the passengers of long-haul flights had better attend to this matter. You should try to get more activities on the airplane, even if it is inconvenient for you to leave your seats, you also should try to move your toes to boost the blood to flow.