Prognostically significant parameters of vector electrocardiography in patients with acute decompensation of heart failure with reduced left ventricular ejection fraction

Computational vector electrocardiography (vECG) is a method for visualizing the total heart vector output in 3-dimensional mode based on 12 lead and distributed computational procedures. This method can be an additional to assess severity and prognosis in patients with acute decompensated heart failure (ADHF). Objective: to investigate the vECG parameters associated with poor prognosis in patients with ADHF. Materials and methods. ECG data of 100 patients with ADHF were analyzed. All patients underwent baseline clinical examination, echocardiography, and a natriuretic peptide (NT-proBNP) test. Mortality was recorded during follow-up for 12 months. The correlation of vECG and NT-proBNP parameters with the prognosis of patients was evaluated. Results. Due to the period of follow-up, 17 patients died. According to vECG data, the surviving patients had a smaller spatial QRS-T angle compared to the deceased patients (p = 0.039). Statistically insignificant values (p = 0.076) of the planarity index in the group of deceased patients were revealed. ROC-analysis revealed the cut-off value of QRS-T spatial angle equal to 164.5°with sensitivity of 53% and specificity of 71%. The QRS-T spatial angle values above the cut-off value indicate a higher probability of lethal outcome. The cut-off value of 999.35 pg/ml of NT-proBNP in patients with the value of QRS-T angle of 164.5° associated with an unfavorable prognosis was revealed. Conclusions. vECG can be used as a simple method to predict and assess the risk of fatal outcome in patients with ADHF and reduced left ventricular ejection fraction. The most significant parameter is the value of QRS-T spatial angle. An increase in the QRS-T spatial angle is associated with an increased risk of fatal outcome. Thus, vECG analysis may be a useful tool for identification of high-risk patients and influence the treatment strategy.