Robert Kelly is managing director of XTS Energy LLC, and has more than three decades of experience as a business executive. He is a professor of economics and has raised more than $4.5 billion in ...

A prolonged QT interval has a variety of causes and can be a very serious ECG finding, as it may lead to the potentially fatal arrhythmia polymorphic ventricular tachycardia (Torsades de Pointes). See ...