Cardiac Safety of Selective Serotonin Reuptake Inhibitors (SSRIs)

Patient Evaluation and Monitoring

The American College of Cardiology recommends obtaining baseline ECG before initiating SSRIs in patients with pre-existing cardiac disease, congenital long QT syndrome, bradycardia, electrolyte abnormalities, recent acute myocardial infarction, uncompensated heart failure, or concomitant use of other QT-prolonging medications 1
The American Heart Association suggests considering discontinuation of citalopram if QTc >500 ms or increase of ≥60 ms from baseline 1
Patients can be stratified into risk groups, with high-risk patients having baseline QTc ≥500 ms (or ≥550 ms with wide QRS) or on combination QT-prolonging therapies, and low-risk patients having no cardiac history, normal baseline QTc, and no concomitant QT-prolonging medications 3

The American College of Cardiology advises monitoring closely when SSRIs are combined with Class I or III antiarrhythmic medications, antipsychotics, certain antibiotics, or other QT-prolonging medications 1
CYP2D6 inhibitors (e.g., quinidine, fluoxetine, paroxetine) should be used with caution when combined with thioridazine due to increased risk of QTc prolongation 1

The American Heart Association recommends being vigilant for ECG findings that may precede torsades de pointes, including QT-U distortion, T wave alternans, enhanced U waves, polymorphic ventricular premature beats, and short-long-short cycle length sequences 1, 2
If QTc exceeds 500 ms or increases by ≥60 ms from baseline, consider alternative pharmacotherapy, assess for drug-drug interactions, check for bradyarrhythmias or electrolyte abnormalities, ensure external defibrillator availability, and restrict patient transport from monitored settings 1

The American College of Cardiology recommends selective monitoring based on risk factors for patients taking other SSRIs, rather than routine ECG monitoring 2
The American Heart Association suggests checking serum potassium and magnesium levels at baseline for high-risk patients, periodically during treatment, and correcting abnormalities before initiating treatment 1