A: Note the loss of sinus rhythm and T-wave alternans with variable extremely long QT intervals. Mean QTc = 660 ms.
[heartrhythmjournal.com]
wave alternans or long pauses followed by abnormal T waves) despite β -blockade and LCSD, and d) sustained ventricular arrhythmias, or sudden cardiac arrest (secondary prevention
[itaca.edu.es]
Furthermore, his symptoms, prolonged QT combined with deafness, QTc 470–500 ms, bradycardia (<60 beats/min), notched T wave in three leads, and T wave alternans, are high-risk
[nature.com]