Pulmonary artery thrombosis. Clinical aspects and the possibility of prognosis

Abstract

BACKGROUND: Recently, there has been a growing interest to the pulmonary artery thrombosis due to the collected data on pathogenesis of this complication and the awareness about developing diagnostic and therapeutic strategy distinctive from those in pulmonary embolism. AIM: To estimate the pulmonary artery thrombosis clinical presentation, its electrocardiographic and echocardiographic signs and the possibility of applying venous thromboembolism risk assessment scores and diagnostic scoring systems in the cohort of deceased patients with verified pulmonary artery thrombosis. MATERIALS AND METHODS: A retrospective study based on the medical records analysis of two groups of deceased patients has been carried out. The first group included 80 patients with pulmonary artery thrombosis and the second one included 42 patients with pulmonary embolism. All the patients’ diagnoses were confirmed by the results of sectional and histological studies. 61 patient with COVID-19 and 19 non-COVID urgent patients with different pathologies were included in pulmonary artery thrombosis group. All 42 patients in pulmonary embolism group had verified venous thrombosis or heart chambers thrombi. Clinical presentation peculiarities, the electrocardiographic and echocardiographic reports as well as the possibility of application of Caprini, IMPROVE VTE, Padua, Wells and Geneva scoring systems were analyzed. RESULTS: None of the 80 pulmonary artery thrombosis patients had hemoptysis, unexpected dyspnoea, sudden strong cough, chest pain, or syncopea. Electrocardiographic changes indicative of right ventricular strain were found in 52.5% in the pulmonary artery thrombosis group and in 57.1% in the pulmonary embolism group. Inversion of T waves, complete and incomplete right bundle branch block were recorded in 14.6% and in 12.5%, in 36.3% and in 47.5% in the pulmonary artery thrombosis group and in the pulmonary embolism group, respectively, without statistical significance between two groups. Echocardiographic findings of right ventricular overload and/or dysfunction were present in 5 out of 10 patients with pulmonary artery thrombosis and in 5 out of 9 patients with pulmonary embolism. The correlation between Caprini, IMPROVE VTE and Padua scores and the incidence of pulmonary artery thrombosis was as strong as with the incidence of pulmonary embolism. On the contrary, Wells and Geneva clinical prediction scores failed to determine the probability of pulmonary artery thrombosis. CONCLUSIONS: Pulmonary artery thrombosis occurs without obvious clinical manifestations typical for pulmonary embolism. Electrocardiography and echocardiography reveal right ventricular overload in pulmonary artery thrombosis and in pulmonary embolism with equal frequency. Patients with high risk of pulmonary artery thrombosis can be identified by using the Caprini, IMPROVE VTE, Padua Prediction scores.