Assessment of the risk of polymorphic ventricular tachycardia development in patients with drug-induced QT interval prolongation caused by class III antiarrhythmic drugs

• Published in: Vestnik Vitebskogo gosudarstvennogo medit︠s︡inkogo universiteta Vol. 21; no. 3; pp. 35 - 45
• Main Authors: V.A. Snezhitskiy, A.V. Kapytski
• Format: Journal Article
• Language: English
• Published: Vitebsk State Order of Peoples’ Friendship Medical University 01-06-2022
• Subjects: class iii antiarrhythmic drugs; drug-induced long qt syndrome; logistic regression; magnesium; polymorphic ventricular tachycardia; qt interval dispersion
• ISSN: 1607-9906; 2312-4156
• DOI: 10.22263/2312-4156.2022.3.35

Objectives. To elaborate a risk assessment model for the development of polymorphic ventricular tachycardia (PVT) in patients with drug-induced long QT syndrome (LQTS) caused by class III antiarrhythmic drugs. Material and methods. The study included 64 patients with drug-induced LQTS, 37 (57.8%) out of them were women and 27 (42.2%) men, their mean age made up 57.2±9.4 years. All patients underwent clinical, laboratory and instrumental studies, including 12-lead ECG recording, 24-hour Holter ECG monitoring while receiving antiarrhythmic therapy. Depending on the presence or absence of unsustainable PVT according to Holter monitoring, the patients were divided into 2 groups: “PVT” (n=17) and “Without PVT” (n=47). Based on the obtained data, a logistic regression equation with a binary response and a logit link function was constructed to predict the development of PVT. Results. A logistic regression model has been elaborated, which includes the following indicators: patients’ gender, serum magnesium level, QT interval dispersion, and index of cardioelectrophysiological balance (QT/QRS). With a calculated threshold probability value of ≥0.599, the resultant model can identify patients at high risk of PVT development with drug-induced LQTS while taking class III antiarrhythmic drugs with a sensitivity of 88.24%, specificity of 90.00% and total accuracy of 89.55%. Conclusions. The developed model will make it possible to predict the risk of ventricular arrhythmias in the sick with drug-induced LQTS, which will lead to a decrease in the number of cardiovascular complications and sudden cardiac death cases in this category of patients.