Evaluation of presence and echogenicity of the residual thrombus in the late phase of venous thrombosis and its association with post-thrombotic syndrome and disease recurrence

Author(s)

Bruna de Moraes Mazetto Fonseca

• Document type: Doctoral Thesis
• Press: Campinas, SP.
• Institution: Universidade Estadual de Campinas (UNICAMP). Faculdade de Ciências Médicas
• Defense date: 2016-02-02

Examining board members

Joyce Maria Annichino Bizzacchi; Fábio Hüsemann Menezes; Kleber Yotsumoto Fertrin; Nelson Wolosker; Daniel Dias Ribeiro

• Advisor: Joyce Maria Annichino Bizzacchi; Fernanda Loureiro de Andrade Orsi

Abstract

Deep venous thrombosis (DVT) is a multifactorial disease that occurs by formation of acute thrombus in the deep venous system. Currently, the major concerns related to DVT are the late sequelae, such as post-thrombotic syndrome (PTS) and DVT recurrence, that may appear even after adequate anticoagulation therapy. The evaluation of residual venous thrombosis (RVT) as a risk factor for both complications has been extensively studied in recent years, but there is no consensus among investigators regarding the role of RVT in the recurrence of DVT and maintenance and severity of PTS, probably due to a lack of a standardized methodology for thrombi evaluation. Thus, the aim of this study was to evaluate if the presence and echogenicity of RVT, evidenced by GSM analysis (grayscale median) of ultrasound images, could be tools to assess late sequelae of DVT. We performed a cross-sectional study designed to evaluate the role of RVT in PTS and a prospective study to evaluate DVT recurrence. Fifty-six patients with previous diagnosis of DVT of lower limbs were included in the study. At the time of inclusion, patients were submited to an ultrasound examination to detect RVT and blood collection for d-dimer measurements. These patients were followed for two years, when they were reconvened to perform a new ultrasound examination, clinical evaluation (to detect PTS and Obesity) and blood collection for measurements of C-reactive protein (CRP) levels. Of the 56 patients included, 41 presented PTS. Mild PTS was detected in 23 patients, moderate PTS in 11 and severe PTS in 7. Patients with severe PTS presented obesity, higher CRP levels and were characterized by the presence of hypoechoechoic RVT when compared to patients with mild-moderate PTS or no PTS. DVT recurrence was observed in 10 patients, all of which presented RVT. D-Dimer levels above 630ng/mL conferred higher risk for recurrence, the absence of RVT was a protective marker for recurrence and the presence of hypoechoic RVT presented predictive value for recurrence. These results indicate that patients with hypoechoic thrombus, after the acute episode of DVT, seem to have a worse clinical outcome compared to patients without hypoechoic thrombus. Thus, the echogenicity of the RVT, by GSM analysis, could represent a new strategy for prognostic evaluation related to late sequelae of DVT (AU)

• FAPESP's process: 12/14082-6 - Evaluation of the persistence of acute thrombus in the late phase of DVT.
• Grantee: Bruna de Moraes Mazetto Fonseca
• Support Opportunities: Scholarships in Brazil - Doctorate