Think prolonged sitting is quite harmless? Not if it results in Chronic Thromboembolic Pulmonary Hypertension (CTEPH), which involves blood clots in the lungs clogging the the arteries. Here’s the thing: these clots could have been formed in the legs during prolonged sitting (i.e. economy class syndrome) or prolonged bed rest (like after surgery).

According to Assistant Professor Victor Chao, a senior consultant at the Department of Cardiothoracic Surgery at National Heart Centre Singapore, the most common symptom of CTEPH is shortness of breath. Some people may also feel weak or tired.

Assistant Professor Victor Chao

The condition is usually diagnosed via an echocardiogram, CT scan, or ventilation-perfusion scans, and a pulmonary endarterectomy [an operation to remove old blood clots from the pulmonary arteries in the lungs] is typically the recommended treatment.

“It has the best long-term result because the clots are surgically removed from the body. Other options include balloon pulmonary angioplasty [an operation that uses balloons to open blood vessels that have been chronically narrowed or blocked] or medical treatment,” says Dr Chao.

He adds that during the procedure, a patient is put under general anaesthesia and put on heart-lung machine support, and that there is a risk of death, stroke, bleeding, infection and kidney failure.

“But since our training in Papworth Hospital in the United Kingdom, we have performed this surgery for 13 patients and all patients have survived. Two if them experienced major complications–one had brain bleeding that required drainage while another needed lung support after surgery–but they recovered fully.”

He also has a few tips on how to avoid getting CTEPH.

“Avoid prolonged sitting or bedrest. Try to get up and move around at least once an hour, maintain a healthy weight and avoid smoking.”

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