Icen YK, et al. - Due to its association with poor prognosis in patients with heart failure reduced ejection fraction (HFrEF), researchers sought to determine the link between positive T wave polarity in lead aVR (TPaVR) and mortality in patients with cardiac resynchronization therapy defibrillator (CRT-D). Investigators retrospectively included 224 HFrEF patients with CRT-D in sinus rhythm in the study group, and categorized them as living or deceased. In the deceased group, TPaVR before CRT-D and TPaVR after CRT-D were found to be significantly positive. Additionally, pulse, hyperlipidemia, and NT-proBNP levels were higher in this group. Overall, a positive TPaVR in surface electrocardiography may be a strong mortality indicator in CRT-D patients.