Electroconvulsive Therapy (ECT)

Definition and Mechanism of Action

Electroconvulsive Therapy (ECT), historically known as electroshock, is a psychiatric procedure used for the treatment of severe, resistant, or urgent forms of depression. It involves the controlled induction of a generalized epileptic seizure through the application of an electrical stimulus to the scalp, administered under general anesthesia and muscle relaxation. It is performed in a hospital setting with continuous monitoring of vital signs and brain activity.

Although its mechanism of action is not yet fully understood, ECT induces widespread neuroplastic and neurotransmitter changes.

Key observed effects include:

• Enhancement of serotonergic, dopaminergic, and noradrenergic pathways involved in mood regulation;
• Modulation of limbic and cortical activity, reducing hyperactivity in areas such as the ventromedial prefrontal cortex and the amygdala;
• Increased hippocampal neurogenesis and availability of brain-derived neurotrophic factor (BDNF);
• Reduction of neuroimmune inflammation and normalization of the HPA axis (hypothalamic-pituitary-adrenal axis).

These effects result in a rapid reduction of depressive symptoms, often after just 2–4 sessions, making ECT one of the most effective and timely treatments in psychiatry.

Indications in Depression

ECT is indicated in patients with unipolar or bipolar major depression who present with at least one of the following conditions:

• Psychotic depression, with mood-congruent delusions or auditory hallucinations;
• Catatonic depression, with mutism, stupor, negativism, or agitation;
• High and imminent suicide risk, requiring rapid intervention;
• Treatment-resistant depression, with documented failure of at least two antidepressants from different classes, possibly combined with augmentation strategies;
• Depression during pregnancy, when avoiding potentially teratogenic psychotropics is preferred.

ECT may also be used as a maintenance treatment to prevent relapse in patients who responded well to the acute course. In such cases, sessions are gradually spaced out (from weekly to monthly), combined with pharmacotherapy.

Administration and Monitoring

The acute course consists of 6–12 sessions, usually performed 2–3 times per week. Before starting, the patient undergoes:

• Anesthetic and cardiological evaluation;
• Blood tests and, if necessary, baseline ECG and EEG;
• An informational interview and signing of the informed consent form.

During each session:

• The patient is sedated with a short-acting anesthetic (e.g., methohexital, propofol);
• A muscle relaxant (e.g., succinylcholine) is administered to prevent muscle contractions;
• Electrodes are placed bilaterally (frontotemporal) or unilaterally (typically right-sided);
• The electrical stimulus induces a seizure, monitored via EEG and clinical observation.

Recovery typically occurs within 30–60 minutes. The course may be interrupted in the event of early complete clinical response or the emergence of significant side effects.

Effectiveness and Clinical Response

ECT is one of the most effective treatments for major depression, with response rates between 70% and 90% in psychotic and catatonic cases, and above 60% in treatment-resistant depression. Compared to pharmacotherapy, the effect is often faster and more pronounced, especially in patients with profound anergia, guilt delusions, or acute suicide risk.

Therapeutic response typically occurs within 4–6 sessions, with improvements continuing even after treatment ends. Complete remission is more likely in patients without severe comorbidities, with illness duration under two years, and no significant personality pathology.

Side Effects and Cognitive Considerations

The side effects of ECT are predictable, dose-dependent, and generally reversible. The most common include:

• Post-treatment headache, easily managed with analgesics;
• Muscle soreness or stiffness due to the muscle relaxant;
• Temporary disorientation upon awakening, especially during early sessions;
• Anterograde and retrograde amnesia: anterograde memory loss is brief; retrograde memory may affect recent events and usually resolves in weeks, though partial persistence may occur;
• Mild transient cognitive slowing, more frequent with bilateral stimulation and prolonged courses.

The risk of cognitive side effects can be reduced with modern techniques: right unilateral stimulation, brief-pulse stimuli, and minimal effective dosage. In elderly patients, a careful balance of efficacy and tolerability is recommended, with neuropsychological reassessment if needed.

Contraindications and Precautions

Absolute contraindications are rare and include:

• Expansive intracranial masses with uncontrolled intracranial hypertension;
• Recent cerebral hemorrhage or high-risk cerebral aneurysms.

Relative contraindications include:

• Severe heart disease (e.g., recent myocardial infarction, unstable heart failure);
• Uncontrolled arrhythmias or non-compatible pacemakers;
• Recent vertebral fractures or untreated severe osteoporosis;
• Unstable metabolic conditions, such as electrolyte imbalances or decompensated endocrine disorders.

In all such cases, specialist evaluation (neurologist, cardiologist, anesthesiologist) is essential before proceeding. ECT remains a safe therapy, with a risk profile far lower than public perception suggests.

Perspectives and Overcoming Stigma

Despite strong evidence of efficacy, ECT remains subject to significant cultural stigma, largely due to distorted media and historical representations. In recent decades, however, the procedure has been extensively reformed in terms of technique, ethics, and clinical practice:

• It is always performed under general anesthesia;
• It is governed by strict protocols and international guidelines;
• It requires thorough and verifiable informed consent.

ECT does not cause addiction, does not alter personality, and does not impair judgment. In many cases, it represents the only treatment capable of resolving severe clinical conditions or saving lives.

References
1. UK ECT Review Group. Efficacy and safety of electroconvulsive therapy in depressive disorders. Lancet. 2003;361:799–808.
2. American Psychiatric Association. The Practice of Electroconvulsive Therapy: Recommendations for Treatment, Training, and Privileging. APA Press. 2001.
3. Kellner CH et al. Relief of expressed suicidal intent by ECT: a consortium for research in ECT study. Am J Psychiatry. 2005;162(5):977–982.
4. Sackeim HA et al. Effect of electrode placement and stimulus dose on the efficacy and cognitive effects of electroconvulsive therapy. NEJM. 2000;343(2):122–130.
5. Loo CK et al. Cognitive side effects of electroconvulsive therapy: a review. J Affect Disord. 2012;139(1):1–8.
6. UK NICE. Depression in adults: recognition and management. Clinical guideline CG90. National Institute for Health and Care Excellence. 2009.
7. Brakemeier EL et al. Electroconvulsive therapy in depression – indications, efficacy and risks. Dtsch Arztebl Int. 2017;114(43):765–772.
8. Fink M. What was learned: studies by the consortium for research in ECT (CORE) 1997–2011. Acta Psychiatr Scand. 2014;129(6):417–426.
9. Heikman P et al. Predictors of response to electroconvulsive therapy in depressed patients. J ECT. 2002;18(3):137–143.
10. Jelovac A et al. Relapse prevention with continuation electroconvulsive therapy: a systematic review. J ECT. 2013;29(1):3–10.