Аннтотация
© 2018 by the authors; licensee Modestum Ltd., UK. Objective: Prolongation of the QT interval in patients with coronary heart disease (CAD) is a risk factor of polymorphic ventricular tachycardia (PVT) and as consequence, the sudden death. Drug-drug interactions (DDI) on metabolic rate involving cytochrome P-450 (CYP) is the one of the major cause of Long QT Syndrome (LQTS). The aim of the present study was to improve the safety of combined pharmacotherapy when using drugs that affect the QT interval. Method and Results: Medication occurrence of potential dangerous combination of medicines that are affected on QT interval duration in patients with CAD are researched (outpatient medical records (patient history) analysis). Clinical relevance of DDI, which are associated with changes in CYP enzyme activity, categorized by drugs.com Medication Guide. Finding potential dangerous combination of medicines that are affected on QT interval duration were administered to patients with CAD in 3.6% cases in outpatient clinical practice. The most often prescribed combination of drugs is amiodarone and torasemide (13.3% evidence of all concomitant administration that are leading to QT prolongation). The potential mechanism of Amiodarone and Torasemide interaction on metabolic rate that are leading to QT prolongation are competitive substrates CYP 2C8 and a result of inhibited CYP 2C9 by amiodarone. Conclusion: Ability to predict the prolongation of the QT interval caused by DDI on metabolic rate make possible to improve the safety concomitant administration to patients with CAD.