Abstract
Cardiac discomfort has been reported periodically in COVID-19-vaccinated individuals. Thus, this study aimed to evaluate the role of myocardial strains in the early assessment of the clinical presentations after COVID-19 vaccination. Totally, 121 subjects who received at least one dose of vaccine within 6 weeks underwent laboratory tests, electrocardiogram (ECG), and echocardiogram. Two-dimensional speckle tracking echocardiography (2D-STE) was implemented to analyze changes in the left ventricular myocardium. After vaccination, 66 individuals (55.4 ± 17.4 years) developed cardiac discomforts, such as chest tightness, palpitations, dyspnea, and chest pain. The ECG readings exhibited both premature ventricular contractions and premature atrial contractions (n = 24, 36.4%), while none of the individuals in the control group manifested signs of cardiac arrhythmia. All had normal serum levels of creatine phosphokinase, creatine kinase myocardial band, troponin, N-terminal pro b-type natriuretic peptide, platelets, and D-dimer. Left ventricular ejection fraction in the symptomatic group (71.41% ± 7.12%) and the control group (72.18% ± 5.11%) (p = 0.492) were normal. Use of 2D-STE presented global longitudinal strain (GLS) and global circumferential strain (GCS) was reduced in the symptomatic group (17.86% ± 3.22% and 18.37% ± 5.22%) compared to the control group (19.54% ± 2.18% and 20.73% ± 4.09%) (p = 0.001 and p = 0.028). COVID-19 vaccine-related cardiac adverse effects can be assessed early by 2D-STE. The prognostic implications of GLS and GCS enable the evaluation of subtle changes in myocardial function after vaccination.