• JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
 
  Bookmark and Share
 
 
Doctoral Thesis
DOI
https://doi.org/10.11606/T.5.2020.tde-03072020-170346
Document
Author
Full name
Kellen Freitas Silva de Almeida
E-mail
Institute/School/College
Knowledge Area
Date of Defense
Published
São Paulo, 2019
Supervisor
Committee
Andrade, José Lázaro de (President)
Lianza, Alessandro Cavalcanti
Morhy, Samira Saady
Parga Filho, José Rodrigues
Title in Portuguese
Estudo da deformação miocárdica do ventrículo esquerdo pelo speckle tracking bidimensional em recém-nascidos prematuros
Keywords in Portuguese
Cardiomiopatias
Diagnóstico por imagem
Ecocardiografia/métodos
Idade gestacional
Recém-nascido prematuro
Abstract in Portuguese
Introdução: Em recém-nascidos prematuros (RNPT), as taxas de mortalidade atribuíveis à persistência do canal arterial (PCA) são maiores. A sobrecarga de volume aumenta o consumo de oxigênio das células miocárdicas, criando um desequilíbrio de oferta e demanda que afeta negativamente a função do ventrículo esquerdo (VE). Anormalidades na deformação miocárdica já foram identificadas como marcadores precoces de disfunção ventricular em crianças e adultos, mas pouco se sabe sobre RNPT. Objetivos: Analisar as medidas de deformação miocárdica do VE através da técnica do Speckle Tracking bidimensional (2DSTE) em RNPT, comparando as medidas de strain e strain rate (SR) de pico sistólico em RNPT com e sem PCA, bem como avaliar a viabilidade e a reprodutibilidade do 2DSTE para analisar a deformação miocárdica do VE nesta população de RNPT. Métodos: Foi utilizado o 2DSTE para determinar as medidas de strain e SR de pico sistólico do VE nos eixos longitudinal, radial e circunferencial, em RNPT com <= 34 semanas de idade gestacional, entre 24 e 72 horas de vida, comparando esses parâmetros em três grupos: Grupo I (n = 21) com PCA hemodinamicamente significante (PCAhs), Grupo II (n = 14) com PCA sem significância hemodinâmica e Grupo III (n = 30) sem PCA. Para testar a reprodutibilidade intraobservador e interobservador das medidas de deformação foram utilizados o teste de coeficiente de correlação intraclasses e o teste de Bland-Altman. Resultados: Dos 85 RNPT elegíveis, as medidas de deformação miocárdica foram adequadas para o estudo em 65 pacientes (76%). O strain de pico sistólico longitudinal foi significativamente maior no Grupo I = -19,0% (-9,1% a -26,6%), quando comparado com Grupo II = -15,3% (-8,0% a -20,0%) e Grupo III = -12,7% (-7,0% a -18,0%); P < 0,001. Os valores médios do strain de pico sistólico radial também foram maiores no Grupo I = 23,5% ± 10,0% quando comparados com Grupo II = 20% ± 8,1% e Grupo III = 18,0% ± 4,3%; P = 0,04, bem como a mediana do strain de pico sistólico circunferencial = -18,0% (-10,0% a -31,0%), -15,9% (-11,0% a -27,0%) e -12,6% (-12,0% a -24,8%) respectivamente; P < 0,001. Os pacientes do grupo I apresentaram todos os valores de SR significativamente maiores quando comparados com os grupos II e grupos III. SR de pico sistólico longitudinal = -1,9s-1 ± 0,4s-1; -1,4s-1 ± 0,4s-1 e -1,3s-1 ± 0,2 s-1-, respectivamente; P = 0.005; SR de pico sistólico radial = 2,9s-1 (1,0s-1 a 4,5s-1), 2,2s-1 (1,4s-1 a 4,2s-1) e 1,9s-1 (1,3s-1 a 3,6s-1), respectivamente; P = 0,007 e SR de pico sistólico circunferencial = -2,2s-1 ± 0,6s-1 vs -1,8s-1 ± 0,4s-1 vs -1,5s-1 ± 0,38s-1, respectivamente; P = 0,004. As análises intra e interobservador não apresentaram viés significativo, apresentando coeficientes de correlação > 0,8 em todos os parâmetros estudados. Conclusões: O presente estudo evidenciou que as medidas de strain e SR de pico sistólico longitudinal, radial e circunferencial são significativamente maiores em RNPT com PCAhs. Além disso, comprovou que a análise da deformação miocárdica através da técnica de 2DSTE é viável e reprodutível em RNPT <= 34 semanas de idade gestacional
Title in English
Study of myocardial deformation of the left ventricle by two-dimensional Speckle Tracking in premature neonates
Keywords in English
Cardiomyopathies
Diagnostic imaging
Echocardiography/methods
Gestational Age
Infant premature
Abstract in English
Background: In premature neonates (PN), mortality rates attributable to patent ductus arteriosus (PDA) are high. Volume overload increases oxygen consumption of myocardial cells, creating supply-and-demand imbalance that adversely affects left ventricular (LV) function. Myocardial deformation abnormalities have already been identified as early markers of ventricular dysfunction in children and adults, but little is known regarding PN. Objectives: To analyze the LV myocardial deformation measurements using the two-dimensional Speckle Tracking (2DSTE) technique in PN by comparing systolic peak strain and strain rate (SR) measurements in PN with and without PCA, as well as assessing viability and the reproducibility of 2DSTE to analyze myocardial LV deformation in this population of PN. Methods: We used 2DSTE to determine the strain and strain rate of LV deformation in PN aged <=34 weeks of gestation at birth, between 24 and 72 hours of life, comparing these parameters in three groups. Group I (n = 21) with hemodynamically significant PDA (hsPDA), Group II (n = 14) with PDA without hemodynamic significance and Group III (n = 30) without PDA. In order to test the intraobserver and interobserver reproducibility of the strain measurements, the intraclass correlation coefficient test and the Bland-Altman were analyzed. Results: Of 85 eligible PN, myocardial deformation measurements were adequate for study in 65 patients (76%). The peak systolic longitudinal strain was significantly higher in Group I = -19.0% (-9.1% to -26.6%) when compared to Group II = -15.3% (-8.0% to -20.0%) and Group III = -12.7% (-7.0% to -18.0%); P < 0.001. The mean values of peak systolic radial strain were also higher in Group I = 23.5% ± 10.0% when compared to Group II = 20.0% ± 8.1% and Group III = 18.0% ± 4.3%; P = 0.04, as well as the median peak systolic circumferential strain values = -18.0% (-10.0% to -31.0%), -15.9% (-11.0% to -27.0%) and -12.6% (-12.0% to -24.8%) respectively; P < 0.001. Patients in Group I had SR values significantly higher when compared to Groups II and III. Peak longitudinal systolic SR = -1.9sec-1 ± 0.4sec-1, 1.4 sec-1 ± 0.4sec-1 and -1.3 sec-1 ± 0.2 sec-1 respectively; P = 0.005. Peak radial systolic SR = 2.9sec-1 (1.0sec-1 to 4.5sec-1), 2.2sec-1 (1.4sec-1 to 4.2sec-1) and 1.9sec-1 (1.3sec-1 to 3.6sec-1) respectively; P= 0.007 and Peak circumferential systolic SR = -2.2sec-1 ± 0.6sec-1 vs -1.8sec-1 ± 0.4sec-1 vs -1.5 sec-1 ± 0.38 sec-1, respectively; P= 0.004. Intra and interobserver analyzes did not present significant bias, showing correlation coefficients > 0.8 in all studied parameters. Conclusion: The present study evidenced that strain and SR measurements of longitudinal, radial and circumferential systolic peak are significantly higher in PN with hsPDA. Besides, proved that the analysis of myocardial deformation through the 2DSTE technique is feasible and reproducible in PN <= 34 weeks of gestational age
 
WARNING - Viewing this document is conditioned on your acceptance of the following terms of use:
This document is only for private use for research and teaching activities. Reproduction for commercial use is forbidden. This rights cover the whole data about this document as well as its contents. Any uses or copies of this document in whole or in part must include the author's name.
Publishing Date
2020-07-03
 
WARNING: Learn what derived works are clicking here.
All rights of the thesis/dissertation are from the authors
CeTI-SC/STI
Digital Library of Theses and Dissertations of USP. Copyright © 2001-2021. All rights reserved.