After being anesthetized and undergoing major surgery, up to one in five patients have increased levels of the protein troponin in their blood. This can be a sign of heart damage. Researchers have analyzed data from before and after the operations of 1,300 patients. The study was focused on leakage of the protein troponin to the blood. This is a biomarker found in blood samples from patients with cardiac muscle damage. This kind of damage is, in turn, associated with cardiovascular disease or heart attacks—Major Adverse Cardiovascular and Cerebrovascular Events (MACCE). An increase in troponin is also common in patients...