Ranolazine Use in R-on-T ECG Patterns

Critical Contraindication

• The American College of Cardiology and American Heart Association guidelines note that ranolazine is contraindicated in patients with QT-prolonging conditions, which includes R-on-T phenomena, as this drug causes dose-dependent QT prolongation and should not be used in patients with pre-existing electrical instability 1, 2

Mechanism of QT Prolongation

• Ranolazine causes dose-related QT interval prolongation through inhibition of the rapid delayed rectifier potassium current (IKr), which prolongs the ventricular action potential 3, 4

Clinical Risk Assessment

• The ACC/AHA guidelines specifically note that ranolazine is contraindicated in patients with QT-prolonging conditions 1, 2

Alternative Management

• The American College of Cardiology recommends that for patients with chronic angina who have R-on-T patterns or other electrical instability, standard antianginal agents that do not prolong QT interval, such as beta-blockers, calcium channel blockers, or long-acting nitrates, should be used 1, 2
• The American College of Cardiology suggests addressing the underlying cause of the R-on-T pattern before considering any antianginal therapy 1