Ultrabrief pulse electroconvulsive therapy for depression: a systematic review and meta-analysis

Ultrabrief pulse (<0.5 millisecond pulse width) electroconvulsive therapy (ECT) is regarded as a cognition-sparing form of ECT. Contrary to some early research, recent randomised trials have reported low remission rates with ultrabrief pulse high-dose right unilateral ECT. The aim of the present systematic review and meta-analysis was to assess acute and long-term outcomes following right unilateral and bilateral forms of ultrabrief pulse ECT in depression. We searched PubMed, Embase, PsycINFO, CENTRAL and ClinicalTrials.gov databases from 01 January 2007 to 17 September 2024 for randomised controlled trials and observational studies reporting on one or more relevant outcomes. Remission, response, relapse and switching rates to other forms of ECT were pooled using random effects models. 30 studies provided data on one or more outcomes. The pooled remission rate (k = 23, n = 1478) was 32.2% (95% CI 26.1%-39.0%) with ultrabrief pulse high-dose right unilateral ECT. Less than half of patients (45.3% [95% CI 39.0%-51.7%]) treated with this form of ECT achieved therapeutic response. Switching to brief-pulse ECT due to perceived inadequate response was common and occurred in 28.1% of patients (95% CI 20.6%-37.0%). Of remitters with ultrabrief pulse high-dose right unilateral ECT treated with continuation pharmacotherapy, 44.1% (95% CI 34.4%-54.3%) relapsed or withdrew within six months of completion of an acute course of ECT. The results of this meta-analysis indicate that acute outcomes following ultrabrief pulse ECT fall short of those expected with conventional brief-pulse ECT. As such, ultrabrief pulse ECT cannot be regarded as "state-of-the-art" ECT.