NEWPORT BEACH, Calif.—In 2003, Lene and Jim Righeimer suddenly lost their four-year-old daughter, Rebecca, to an undetected genetic cardiac arrhythmia. Doctors knew that Rebecca had succumbed to a sudden cardiac death (SCD), but they couldn’t pinpoint why at the time. Lene Righeimer said her husband had sprayed for ants the day before. They thought maybe she had been poisoned, or had otherwise been exposed to something that triggered her heart attack. An autopsy was not performed, so blood samples were not able to be tested for a genetic issue. Doctors pronounced Rebecca’s death as due to “natural causes,” failing to identify her Long QT Type 1 syndrome. Although the guidance came too late for the Righeimer family, the American Academy of Pediatrics on June 21 encouraged doctors to routinely screen children for heart conditions that could lead to sudden death if undetected. Solving a Mystery Righeimer, who was pregnant at …