A Chinese man has miraculously survived after his heart stopped beating for 40 hours, sparking an online discussion about the latest life-saving medical techniques.

The case came to light after emergency doctor Lu Xiao from the Second Affiliated Hospital of Zhejiang University School of Medicine posted it on his social media account, which has three million followers.

Lu said the 40-year-old man had a cardiac arrest and no heartbeat could be found after several electric defibrillations.

The...