A 65-year-old man with treatment-resistant depression presents to the clinic for follow-up. He has taken multiple medications with no improvement in symptoms. He also complains of not having the time or motivation to do anything because of his excessive sleep and severe headaches. Protriptyline is prescribed. Which of the following ECG changes is most likely to occur with this medication in this patient? A. QRS shortening B. ST-elevation C. Tall T-waves D. QRS widening