What are examples of EKG (electrocardiogram) changes in patients with psychosis?

ECG Changes in Patients with Psychosis

The most common ECG change in patients with psychosis is QTc interval prolongation, which is primarily associated with antipsychotic medications rather than psychosis itself. This cardiac effect requires monitoring due to the risk of potentially fatal arrhythmias.

Common ECG Changes Associated with Psychosis Treatment

QTc Interval Prolongation

• QTc prolongation is the most significant ECG change seen in patients treated for psychosis 1
• Antipsychotics can cause a quinidine-like QTc prolongation, potentially resulting in dangerous dysrhythmias such as torsades de pointes 1
• First-generation antipsychotics generally cause more QTc prolongation than second-generation agents 2
• Specific high-risk medications:
  • Chlorpromazine, intravenous haloperidol, sultopride, and thioridazine show the greatest risk 2
  • Second-generation antipsychotics (olanzapine, quetiapine, risperidone, zotepine) generally cause less QTc prolongation 2

Other ECG Changes

• Sinus tachycardia (increased heart rate) 1, 3
• Orthostatic hypotension 1
• Minor ECG changes that may not reach clinical significance 1

Risk Factors for ECG Changes

Several factors increase the risk of developing significant ECG changes in patients with psychosis:

• Female gender: 3.4 times higher risk of QTc prolongation 4
• Advanced age: Risk increases by 4% per year of age 4
• Medication dose: Higher doses correlate with increased risk 4
• Electrolyte disturbances: Particularly hypokalemia and hypomagnesemia 1
• Pre-existing cardiac disease: Significantly increases risk 1
• Polypharmacy: Especially with other QT-prolonging medications 1

Prevalence of ECG Changes

Research shows significant prevalence of ECG changes in psychosis patients:

• Approximately 11.6% of acutely admitted psychosis patients have abnormally prolonged QTc intervals 5
• Another 14.3% have borderline QTc prolongation 5
• These proportions typically decrease after stabilization of treatment 5

Monitoring Recommendations

Given the risk of ECG changes, guidelines recommend:

1. Baseline ECG assessment before initiating antipsychotic treatment, especially with known QT-prolonging agents 1
2. Follow-up ECG within 1-2 weeks after starting treatment or after significant dose increases 1
3. Immediate ECG evaluation if cardiac symptoms develop (palpitations, syncope, dizziness) 1
4. Discontinuation of medication if QTc exceeds 500ms or increases >60ms from baseline 1

Clinical Implications

• QTc prolongation >500ms significantly increases the risk of torsades de pointes and sudden cardiac death 1
• ECG monitoring is particularly important in high-risk patients (elderly, females, those with cardiac disease) 4
• Consider switching to antipsychotics with lower risk of QTc prolongation in patients with baseline QTc prolongation 2

Common Pitfalls to Avoid

• Failure to obtain baseline ECG before starting antipsychotics
• Overlooking drug interactions that may potentiate QTc prolongation
• Ignoring electrolyte abnormalities that can exacerbate QTc prolongation
• Missing early signs of cardiac complications (syncope, palpitations)
• Continuing high-risk medications despite significant QTc prolongation

While psychosis itself is not directly associated with specific ECG changes, the medications used to treat it commonly cause ECG abnormalities that require careful monitoring and management to prevent potentially fatal cardiac complications.