Question: how to correct qtc for bundle branch block?
Answer: A formula for LBBB patients was then derived as: QTc-LBBB = [QT - (0.7 * QRS - 50)] / sqrt RR. It is highly agreeable with each other when compared the QTc value obtained by using this formula to the baseline QTc at SR (440 ± 20ms vs 442 ± 20ms, p = 0.91).