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Reproducibility of left ventricular mass by echocardiogram in the ELSA-Brasil.

Tognon AP, Foppa M, Luft VC, Chambless LE, Lotufo P, El Aouar LM, Fernandes LP, Duncan BB - Arq. Bras. Cardiol. (2014)

Bottom Line: No significant difference existed between online and offline measurements (1,29 g, CI 95% -3.60-6.19), and the intraclass correlation coefficient between them was 0.79 (CI 95% 0.71-0.85).There were no significant drifts between online and offline left ventricular mass measurements, and reproducibility was similar to that described in previous studies.Central quantitative assessment of echocardiographic studies in reading centers, as performed in the ELSA-Brasil study, is feasible and useful in clinical and epidemiological studies performed in our setting.

View Article: PubMed Central - PubMed

Affiliation: Programa de Pós-Graduação em Epidemiologia, Faculdade de Medicina, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil.

ABSTRACT

Background: Echocardiography, though non-invasive and having relatively low-cost, presents issues of variability which can limit its use in epidemiological studies.

Objective: To evaluate left ventricular mass reproducibility when assessed at acquisition (online) compared to when assessed at a reading center after electronic transmission (offline) and also when assessed by different readers at the reading center.

Methods: Echocardiographers from the 6 ELSA-Brasil study investigation centers measured the left ventricular mass online during the acquisition from 124 studies before transmitting to the reading center, where studies were read according to the study protocol. Half of these studies were blindly read by a second reader in the reading center.

Results: From the 124 echocardiograms, 5 (4%) were considered not measurable. Among the remaining 119, 72 (61%) were women, mean age was 50.2 ± 7.0 years and 2 had structural myocardial abnormalities. Images were considered to be optimal/ good by the reading center for 110 (92.4%) cases. No significant difference existed between online and offline measurements (1,29 g, CI 95% -3.60-6.19), and the intraclass correlation coefficient between them was 0.79 (CI 95% 0.71-0.85). For images read by two readers, the intraclass correlation coefficient was 0.86 (CI 95% 0.78-0.91).

Conclusion: There were no significant drifts between online and offline left ventricular mass measurements, and reproducibility was similar to that described in previous studies. Central quantitative assessment of echocardiographic studies in reading centers, as performed in the ELSA-Brasil study, is feasible and useful in clinical and epidemiological studies performed in our setting.

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Related in: MedlinePlus

Differences between the measurements from which LVM was estimated, performed fromimages obtained on the two-dimensional mode in the acquisition and reading centers(y axis) and the mean of both measurements (x axis). A: Left ventricular diameter;B: left ventricular posterior wall thickness; C: septal thickness; D: leftventricular mass. The solid line indicates the mean difference between bothmeasurements, and the dashed line indicates the mean ± two standarddeviations.
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f01: Differences between the measurements from which LVM was estimated, performed fromimages obtained on the two-dimensional mode in the acquisition and reading centers(y axis) and the mean of both measurements (x axis). A: Left ventricular diameter;B: left ventricular posterior wall thickness; C: septal thickness; D: leftventricular mass. The solid line indicates the mean difference between bothmeasurements, and the dashed line indicates the mean ± two standarddeviations.

Mentions: Figure 1 shows the differences between valuesobtained at the acquisition centers and those obtained at the reading center on thebasis of the mean LVM readings, estimated using two-dimensional measurements(Bland–Altman plots). There was no notable tendency among online and offlinemeasurements. In 95% samples, the differences were less than 0.7 cm, 0.3 cm, and 0.4 cmfor the LV diastolic diameter, septum thickness, and posterior wall thickness,respectively. LVM was calculated from these three variables and showed a discrepancy of54 g or lower in 95% of samples. There were no association trends between magnitude andamplitude differences in these variables.


Reproducibility of left ventricular mass by echocardiogram in the ELSA-Brasil.

Tognon AP, Foppa M, Luft VC, Chambless LE, Lotufo P, El Aouar LM, Fernandes LP, Duncan BB - Arq. Bras. Cardiol. (2014)

Differences between the measurements from which LVM was estimated, performed fromimages obtained on the two-dimensional mode in the acquisition and reading centers(y axis) and the mean of both measurements (x axis). A: Left ventricular diameter;B: left ventricular posterior wall thickness; C: septal thickness; D: leftventricular mass. The solid line indicates the mean difference between bothmeasurements, and the dashed line indicates the mean ± two standarddeviations.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4375653&req=5

f01: Differences between the measurements from which LVM was estimated, performed fromimages obtained on the two-dimensional mode in the acquisition and reading centers(y axis) and the mean of both measurements (x axis). A: Left ventricular diameter;B: left ventricular posterior wall thickness; C: septal thickness; D: leftventricular mass. The solid line indicates the mean difference between bothmeasurements, and the dashed line indicates the mean ± two standarddeviations.
Mentions: Figure 1 shows the differences between valuesobtained at the acquisition centers and those obtained at the reading center on thebasis of the mean LVM readings, estimated using two-dimensional measurements(Bland–Altman plots). There was no notable tendency among online and offlinemeasurements. In 95% samples, the differences were less than 0.7 cm, 0.3 cm, and 0.4 cmfor the LV diastolic diameter, septum thickness, and posterior wall thickness,respectively. LVM was calculated from these three variables and showed a discrepancy of54 g or lower in 95% of samples. There were no association trends between magnitude andamplitude differences in these variables.

Bottom Line: No significant difference existed between online and offline measurements (1,29 g, CI 95% -3.60-6.19), and the intraclass correlation coefficient between them was 0.79 (CI 95% 0.71-0.85).There were no significant drifts between online and offline left ventricular mass measurements, and reproducibility was similar to that described in previous studies.Central quantitative assessment of echocardiographic studies in reading centers, as performed in the ELSA-Brasil study, is feasible and useful in clinical and epidemiological studies performed in our setting.

View Article: PubMed Central - PubMed

Affiliation: Programa de Pós-Graduação em Epidemiologia, Faculdade de Medicina, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil.

ABSTRACT

Background: Echocardiography, though non-invasive and having relatively low-cost, presents issues of variability which can limit its use in epidemiological studies.

Objective: To evaluate left ventricular mass reproducibility when assessed at acquisition (online) compared to when assessed at a reading center after electronic transmission (offline) and also when assessed by different readers at the reading center.

Methods: Echocardiographers from the 6 ELSA-Brasil study investigation centers measured the left ventricular mass online during the acquisition from 124 studies before transmitting to the reading center, where studies were read according to the study protocol. Half of these studies were blindly read by a second reader in the reading center.

Results: From the 124 echocardiograms, 5 (4%) were considered not measurable. Among the remaining 119, 72 (61%) were women, mean age was 50.2 ± 7.0 years and 2 had structural myocardial abnormalities. Images were considered to be optimal/ good by the reading center for 110 (92.4%) cases. No significant difference existed between online and offline measurements (1,29 g, CI 95% -3.60-6.19), and the intraclass correlation coefficient between them was 0.79 (CI 95% 0.71-0.85). For images read by two readers, the intraclass correlation coefficient was 0.86 (CI 95% 0.78-0.91).

Conclusion: There were no significant drifts between online and offline left ventricular mass measurements, and reproducibility was similar to that described in previous studies. Central quantitative assessment of echocardiographic studies in reading centers, as performed in the ELSA-Brasil study, is feasible and useful in clinical and epidemiological studies performed in our setting.

Show MeSH
Related in: MedlinePlus