Analysis of Fragmentation QRS Complex and Early Repolarization Pattern in Patients with Myocardial Inflammatory Changes

Inflammatory changes in the myocardium create the prerequisites for the electrical instability of the myocardium, which can affect the ECG. It is promising to study relatively new electrocardiographic patterns: fragmentation of QRS (FQRS) and premature ventricular beats (FPVB) and early repolarization pattern (ERP) to improve the screening of patients with suspected myocarditis. Aim. To study FQRS, FPVB and ERP in patients with inflammatory changes in the myocardium. Material and methods. The study included 46 patients (78.3% male, 21.7% women) with suspected myocarditis. Age: median 47.5, quartile 37; 56.5. In all patients, the anamnesis, results of ECG, echocardiography, cardiac magnetic resonance imaging and endomyocardial biopsy were analyzed. Results. The patients were divided into three groups: the 1st – 20 patients with inflammatory and fibrotic changes in the myocardium, the 2nd – 20 patients with myocardial fibrosis without inflammatory, the 3rd – 6 patients without structural changes in the myocardium. FQRS in the 1st group was detected in 35% of the examined, in the 2nd – in 25%, in the 3rd – not registered. FPVB in the 1st group was determined in 55% of the examined, in the 2nd – in 30%, in the 3rd – in 33.3%. ERP in the 1st group was registered in 30% of the examined, in the 2nd group it was not detected, in the 3rd group – in 16.7%. FPVB and ERP were informative for the detection of inflammation (sensitivity – 57.9 and 85% respectively, specificity – 69.2 and 53.8% respectively). For the detection of fibrosis, FPVB proved to be the most informative (sensitivity – 80.0%, specificity – 59.1%). Conclusions. FQRS, FPVB, and ERP are significant ECG-markers for detecting both inflammatory changes in the myocardium and fibrosis. The use of these ECG-markers in routine clinical practice may have an impact on further management of patients with suspected myocarditis.