Cao Yunshan, 41, represents the best hope for many pulmonary hypertension (PH) patients in China, especially those in the remote rural areas of Northwest China's Gansu province.

A post-doctoral fellow at the Harvard Medical School, Cao returned to China in 2016, shouldering the responsibility of curing patients suffering great pain.

PH is known as the "cancer" of the cardiopulmonary vascular system. With difficulty breathing due to a lack of oxygen in the lungs, many patients are unable to walk even a short distance or climb stairs. To make matters worse, PH is often misdiagnosed or mistaken owing to its common symptoms with other illnesses.

China has an estimate of 5 to 8 million PH patients, and morbidity is higher in high-altitude and rural areas, according to Cao.

Cao has saved many PH patients while serving as the deputy director of the cardiovascular department at Gansu Provincial Hospital. One patient had been misdiagnosed and his PH had developed into severe heart failure before he sought help from Cao. After consultation and procedure, Cao's team eventually cured the patient and the case was published in an internationally renowned journal.

Cao also holds seminars in the hospital to help his colleagues familiarize themselves with the disease, which has greatly reduced the misdiagnosis rate.

Cao's return has filled the gap in PH treatment in the province, where patients used to seek treatment in big cities such as Beijing or Shanghai.

Cao is committed to promoting standardized PH diagnosis and treatment. He has traveled to all 10 cities and prefectures in the province, training grassroots doctors while holding free consultations.

On May 5 each year, World PH Day, he contacts many hospitals and personnel from all walks of life to undertake consultations and raise public awareness of the disease.

In 2018, the hospital set up a specialized department for PH, which had provided standardized treatment for more than 600 patients. Cao's team is often invited by hospitals in Beijing, Sichuan and other localities to assist in treatment.

Cao is now leading two teams to develop new treatment methods and research how to improve patient recovery.

"I hope to train more doctors who can take charge of treatment on their own, so that more patients can breathe freely," he said.