Volusia County middle school and high school student-athletes will be offered free electrocardiogram (ECG) screenings for the first time this summer in addition to the annual state-required sports physical. Sudden cardiac arrest is one of the leading causes of death among high school athletes, with an estimate of 1 in 300 student-athletes having an undetected heart condition that puts them at risk.   The goal of the screenings, approved Tuesday by the Volusia County School Board in partnership with AdventHealth, is early detection and treatment of heart abnormalities.