The electrophysiological effects of recently approved angina drug ranolazine (Ranexa) may one day improve survival among patients with Long QT Syndrome (LQTS), a hereditary irregularity that causes sudden cardiac arrest. Approximately 1,000 people—mostly teenagers—die each year when this silent condition is triggered by sudden shocks like sports injuries or strong emotions, leading to a longer QT interval that raises arrhythmia risk when the heart fails to "reset." Linking data that revealed arrhythmia risk in angina patients to an electrical side effect of ranolazine that had appeared in clinical trials, researchers ran controlled tests on LQTS patients, which demonstrated that the drug shortened the QT interval by enough time to cut patients' risk of death.

http://Eurekalert.org/. "Angina drug potentially useful against heart rhythm disorders." 2008. http://www.eurekalert.org/pub_releases/2008-03/uorm-adp033108.php/ (2 Apr. 2008).