80 patients with TRD will be assigned to active or sham rTMS before ECT treatment. Five sessions of active/sham rTMS will be administered over the left dorsolateral prefrontal cortex (20 Hz, 90% resting motor threshold, 20 2 s trains with 60-s intervals, 800 pulses/session) before ECT (which was active for all patients) started. Then, from the sixth ECT session, an rTMS session will occur the day before each ECT session. Clinical assessment, cognitive assessment and brain imaging (structural MRI, resting state functional MRI, MR spectroscopy) will take place before and after 10 ECT sessions. Clinical, cognitive and neural changes will be compared between both groups after 10 ECT sessions.
The primary outcome will be the response rate after 10 ECT, i.e. the percentage of patients who achieved a reduction of 50% or more from their initial Hamilton Depression Scale score (HAMD-21 items).