Life-threatening pacemaker dysfunction associated with therapeutic radiation: a case report.

Reports about pacemaker (PM) dysfunction during irradiation (IR) are very rare, which is because of the extensive protective mechanisms that exist in these devices against electromagnetic interference (EMI). We report a case in which one of the most clinically relevant type of PM malfunctions, a runaway PM, occurred during radiation in a 76-year-old woman who was treated for inoperable esophageal cancer with a course of photon IR. The estimated IR dose of 0.