Overcoming the defects of a virtue: dual-chamber versus single-chamber detection enhancements for implantable defibrillator rhythm diagnosis: the detect supraventricular tachycardia study.

“Mission critical” is a uniquely American cliché generally held to mean an action or series of actions essential for the success of an important endeavor. Randomized clinical trials have conclusively demonstrated that implantable cardioverter-defibrillators (ICDs) reduce mortality among appropriately selected patients who have survived an episode of life-threatening ventricular arrhythmia or are at risk for ventricular arrhythmia. The mission critical aspect of ICD operation is accurate recognition and termination of ventricular arrhythmia. Reproducibly reliable delivery of this critical series of actions is sufficient to guarantee mortal benefit.