ECT has historically been administered with brief pulses (1 ms in width). While some studies suggest ECT delivered with ultrabrief pulses (0.25-0.37 ms) may show similar rates of efficacy as the standard method, others have produced conflicting results.
Colleen Loo, M.D., a professor of psychiatry at the University of New South Wales, and colleagues conducted a systematic review of studies comparing brief pulse and ultrabrief pulse right unilateral ECT in patients that reported mood ratings for depression. They identified six studies involving 689 patients (261 receiving brief pulse right unilateral ECT and 428 receiving ultrabrief pulse right unilateral ECT) and used statistical analysis to examine the efficacy and cognitive side effects of brief pulse versus ultrabrief pulse right unilateral ECT.
The analysis revealed that while brief pulse ECT has a small efficacy advantage (reflected in both mean change in mood ratings, remission rates over the ECT course, and one fewer session in the treatment course) over ultrabrief pulse ECT, it was associated with significantly more cognitive side effects in all cognitive domains examined, including global cognition, anterograde learning and recall, and retrograde memory.
"The decision of whether to use BP [brief pulse] or UBP [ultrabrief pulse] RUL [right unilateral] ECT should be made on an individual patient basis and should be based on a careful weighing of the relative priorities of efficacy versus minimization of cognitive impairment," the study authors concluded.
For related information, see the Psychiatric News article “Psychiatrists Discuss Benefits, Risks of ECT.”