How a Cell Transplant Can Set the Heart's Pace
After a heart attack, the dead section of heart muscle can be replaced with living cells grown from stem cells. But a common problem arises: the fresh transplant starts acting as its own pacemaker, and the heart falls out of its proper rhythm. Doctors see the arrhythmia on an ECG, but what exactly happens at the junction between 'self' and 'foreign' remains hidden.