Editorial T-wave alternans: predicting the unpredictable?

This editorial refers to ‘T-wave alternans predicts mor-tality in a population undergoing a clinically indicated excercise test ’ by T. Nieminen et al., on page 2332 Sudden cardiac death (SCD) due to ventricular arrhythmias has a high morbidity and mortality. It is no wonder that car-diologists, rather than patching up survivors, are dedicated to finding predictors of cardiac electrical instability to prevent SCD. The implantable cardiac defibrillator (ICD) has evolved as the ultimate strategy for sudden arrhythmic death. In secondary prevention, individuals are recognized by an aborted arrhythmic event. By stratifying according to left ventricular ejection fraction (LVEF) below 35%, SCD may also be prevented by an ICD in individuals without any prior arrhythmic event.1 However, the relative SCD risk based on LVEF alone is lower, and additional stratifiers ar