This may be a rare complication but it is STILL just one complication (an extremely serious one) for a treatment that has not shown to be beneficial. Therefore, the risk outweighs any benefit.
A 48-year-old korean woman was brought to the emergency department due to hypotension and drowsiness. She had a history of left mastectomy followed by chemotherapy due to breast cancer seven years ago. Otherwise her past medical history was unremarkable. She suddenly developed bradycardia, syncope and became comatose about 10 minutes after an acupuncture session, in which a needle was inserted into the left anterior parasternal area at the level of the 4th intercostal space by a professional acupuncturist.
Cardiac tamponade is when pressure on the heart occurs because blood or fluid builds up in the space between the heart muscle and the outer covering of the heart, pericardium. In this case it was supposed that even an experienced acupuncturist might penetrate the cardiac chamber or the coronary arteries with acupuncture needles (which are 30 mm in length) because the distance from the surface of the skin to the surface of heart may have been thinner due to the woman’s mastectomy. She lived. Regardless, this is SERIOUS because she could have died.
Again, while all treatments carry some risk, acupuncture HAS BEEN RATHER CLEARLY SHOWN TO BE INEFFECTIVE. Why would you take the risk of infection or injuring your internal organs for nothing!?