SPC365

Is myocardial fibrosis appropriately assessed by 2D Strain derived integrated backscatter?

Session: Posters (Sessão 2 - Écran 7) - Ecocardiografia
Speaker: Maria Rita Giestas Lima

Congress: CPC 2023
Topic: B. Imaging
Theme: 03. Imaging
Subtheme: 03.1 Echocardiography
Session Type: Pósters Electrónicos
FP Number: ---
Authors: Maria Rita Giestas Lima; João Abecasis; Rita Reis Santos; Sérgio Maltês; Sara Guerreiro; Carolina Campino Padrão; Pedro Freitas; António Ferreira; Regina Ribeiras; Maria João Andrade; Nuno Cardim; Márcio Madeira; Sância Ramos; Miguel Mendes

<p><span style="font-size:11pt"><span style="font-family:Calibri,sans-serif"><strong><span style="font-family:&quot;Times New Roman&quot;,serif">INTRODUCTION </span></strong></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Calibri,sans-serif"><span style="font-family:&quot;Times New Roman&quot;,serif">Calibrated integrated backscatter (cIBS) may be obtained from bidimensional (2D) strain echocardiography as a quantification measurement of myocardial ultrasound reflectivity. Increased collagen content of the myocardium modifies tissue reflectivity and cIBS is suggested as a marker of left ventricular (LV) fibrosis. However, its diagnostic accuracy is not established.</span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Calibri,sans-serif"><strong><span style="font-family:&quot;Times New Roman&quot;,serif">AIM </span></strong></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Calibri,sans-serif"><span style="font-family:&quot;Times New Roman&quot;,serif">To assess the correlation between cIBS by 2D strain and LV myocardial fibrosis (MF), as evaluated by non-invasive imaging and histopathology.</span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Calibri,sans-serif"><strong><span style="font-family:&quot;Times New Roman&quot;,serif">METHODS </span></strong></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Calibri,sans-serif"><span style="font-family:&quot;Times New Roman&quot;,serif">Correlation study from a cohort of 157 patients with severe symptomatic aortic stenosis (AS) referred for surgical aortic valve replacement (AVR). Patients with complete preoperative transthoracic echocardiography, cardiac magnetic resonance (CMR) and endomyocardial biopsy (EMB) obtained from the anterior basal septum at the time of AVR were selected. Two groups of 30 patients were evaluated, with and without late gadolinium enhancement (LGE) at CMR. IBS was obtained at QRS peak in decibels (dB) from both parasternal long axis (PLAX) and apical three chamber (A3C) cine clips at <em>Qanalysis</em> (Figure 1A). cIBS was calculated by subtracting the pericardial intensity from the average of the anteroseptal and basal inferolateral wall values. Correlation analysis was performed for the whole group of patients with global and segmental (anterior basal septum) values of native T1 and extracellular volume (ECV), and EMB collagen volume fraction (CVF) from Masson&acute;s Trichrome staining. IBS values were compared in both groups of patients.</span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Calibri,sans-serif"><strong><span style="font-size:12.0pt"><span style="font-family:&quot;Times New Roman&quot;,serif">RESULTS</span></span></strong></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Calibri,sans-serif"><span style="font-family:&quot;Times New Roman&quot;,serif">60 patients (73 [68-74] years, 45% male) with high gradient (mean gradient: 64&plusmn;20mmHg), normal flow (45&plusmn;10mL/m<sup>2</sup>), preserved ejection fraction (60&plusmn;9%) AS. Basal septal cIBS was -9.2&plusmn;9.5 dB and -16.3&plusmn;7.9 dB from A3C and PLAX views, respectively. These indexes did not correlate with basal septum thickness or global LV mass. Absolute and cIBS did not correlate neither with global and regional T1 and ECV values, nor with CVF at EMB (Figure 1B). These were not significantly different in both groups of patients and there was no correlation between cIBS values and mass of replacement MF in patients with LGE. </span></span></span></p>

<p><span style="font-size:11pt"><span style="font-family:Calibri,sans-serif"><strong><span style="font-size:12.0pt"><span style="font-family:&quot;Times New Roman&quot;,serif">CONCLUSION</span></span></strong></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Calibri,sans-serif"><span style="font-family:&quot;Times New Roman&quot;,serif">In these cohort of patients with classical severe AS, there was no correlation of cIBS with imaging markers of both replacement and diffuse MF. cIBS also didn&acute;t correlate with CVF at histopathology. These findings suggest that reflectivity indexes are not suitable for myocardial tissue characterization in this setting. </span></span></span></p>