Overload of the Right Ventricle in Patients with Pulmonary Embolism: Analysis of New Evaluation Criteria

INTRODUCTION: The increasing incidence of pulmonary embolism (PE) and high mortality from it necessitates development of new echocardiographic (EchoCG) criteria for assessing the severity of pressure and volume overload of the right ventricle (RV) in patients with PE. AIM: To perform critical analysis of the developed EchoCG criteria of overload of the right heart chambers in PE with the aim to determine severity of the course and outcomes of the disease. MATERIALS AND METHODS: The study included 428 patients with PE divided to 4 groups: group 1 42 patients with recorded death, group 2 51 patients with hemodynamically significant disease, group 3 193 hemodynamically stable patients with EchoCG signs of the overload of the right ventricle, group 4 142 patients with no identified symptoms. Comparison of the developed EchoCG criteria was conducted: the volume of tricuspid regurgitation, its ratio to the volume of the right atrium and the stroke volume of the heart, and also the pressure in the pulmonary trunk, the pressure gradient on the pulmonic valve and its ratio to the pressure gradient on the tricuspid valve in the studied groups with the determination of threshold values having diagnostic and prognostic significance. RESULTS: It was found that the level of the estimated pressure gradient on the pulmonic valve has statistically significant correlation with the hemodynamic significance of the course of the disease (r = 0.91, р 0.01) and fatal outcome (r = 0.99, р 0.01) and possesses high sensitivity (more than 92.7%) and specificity (more than 97.8%). This parameter is proved to be the most important prognostic EchCG criterion. To determine the expression of the RV dysfunction and the priority flow of blood from its cavity, the following parameters equivalent to EhcoCG, such as the ratio of pressure gradient on the pulmonic artery to the pressure gradient on the tricuspid valve and the ratio of the tricuspid regurgitation volume to the stroke volume, are also significant. CONCLUSION: Calculation of the pressure gradient on the pulmonic valve and its correlation with the pressure gradient on the tricuspid valve, just as the ratio of the volume of tricuspid regurgitation to the stroke volume can be reliable criteria for assessment of the hemodynamic significance of PE and predictors of its outcome.