SPC365

Genotype-Phenotype Correlations with Late Gadolinium Enhancement Patterns in Primary Cardiomyopathy

Session: SESSÃO DE POSTERS 19 - IMAGEM NAS MIOCARDIOPATIAS
Speaker: Maria Rita Lima

Congress: CPC 2025
Topic: B. Imaging
Theme: 03. Imaging
Subtheme: 03.3 Cardiac Magnetic Resonance
Session Type: Cartazes
FP Number: ---
Authors: Maria Rita Giestas Lima; Rita Amador; Sérgio Maltês; Pedro Lopes; Pedro Freitas; Sara Guerreiro; João Abecasis; Catarina Brízido; Christopher Strong; Carlos Aguiar; António Ferreira; Bruno Rocha

<p style="text-align:justify"><span style="font-size:12pt"><span style="font-family:Aptos,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:12pt"><span style="font-family:Aptos,sans-serif"><span style="font-family:&quot;Times New Roman&quot;,serif">Late gadolinium enhancement (LGE) is commonly observed in primary cardiomyopathy. However, limited data exist regarding its prevalence and distribution in relation to specific genes. This study aimed to assess the genotype-phenotype correlations with LGE patterns in primary cardiomyopathy.</span></span></span></p>

<p style="text-align:justify"><span style="font-size:12pt"><span style="font-family:Aptos,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:12pt"><span style="font-family:Aptos,sans-serif"><span style="font-family:&quot;Times New Roman&quot;,serif">This is a single-centre study of consecutive patients with dilated cardiomyopathy (DCM) and non-dilated left ventricular cardiomyopathy who are followed in our centre (at least yearly) undergoing cardiac magnetic resonance (CMR) plus DCM-related genes testing. Baseline clinical, laboratory, ECG and CMR data were systematically collected. Patients were categorized into 3 groups based on genetics: pathogenic/likely pathogenic variants (P/LPV), variants of uncertain significance (VUS) and negative test (NT). </span></span></span></p>

<p style="text-align:justify"><span style="font-size:12pt"><span style="font-family:Aptos,sans-serif"><strong><span style="font-family:&quot;Times New Roman&quot;,serif">Results</span></strong></span></span></p>

<p style="text-align:justify"><span style="font-size:12pt"><span style="font-family:Aptos,sans-serif"><span style="font-family:&quot;Times New Roman&quot;,serif">Overall, 119 patients [71% female, 51&plusmn;16 years, 85% with dilated left ventricle </span><span style="font-size:11.0pt"><span style="font-family:&quot;Times New Roman&quot;,serif">(</span></span><span style="font-family:&quot;Times New Roman&quot;,serif">LV), LV ejection fraction (LVEF) 34%] were included. Genetic testing revealed potential causative variants in DCM-related genes in 89 (75%) patients, of whom 46 were identified with a P/LPV and 43 with a VUS. The most common P/LPV were LMNA (20%), PKP2 (17%), FLNC (13%) and TTN (11%). Compared with patients with VUS or a NT, patients with P/LPV were younger (45 <em>vs.</em> 53 <em>vs.</em> 59 years for P/LPV, VUS and NT, respectively; p&lt;0.001), and presented with lower NT-proBNP (186 <em>vs.</em> 225 <em>vs.</em> 459pg/mL, respectively; p=0.003) and higher LVEF (41 <em>vs.</em> 32 <em>vs.</em> 34%; p=0.036). </span></span></span></p>

<p style="text-align:justify"><span style="font-size:12pt"><span style="font-family:Aptos,sans-serif"><span style="font-family:&quot;Times New Roman&quot;,serif">Figure 1 illustrates the distribution of patients according to the LGE patterns, categorized by genes (P/LPV+VUS and P/LPV). No differences were found in the prevalence, extensiveness and pattern of LGE between genetic groups. Patients with PV/LPV in FLNC/PKP2 genes more often had a sub-epicardial pattern (p=0.018), while TTN/LMNA had numerically more patients with mid-mural LGE when compared to VUS and NT (82 <em>vs.</em> 44%; p=0.124). Those with P/LPV in DSP more often had a sub-epicardial pattern (100 <em>vs.</em> 33%, p=0.009) and &ldquo;ring-like&rdquo; LGE (100 <em>vs.</em> 17%, p&lt;0.001), while TTN patients showed lower LVEF (29 <em>vs.</em> 42%; p&lt;0.001) and more often mid-wall LGE (80 <em>vs.</em> 27%; p=0.017), when compared with other patients with P/LPV. </span></span></span></p>

<p style="text-align:justify"><span style="font-size:12pt"><span style="font-family:Aptos,sans-serif"><strong><span style="font-family:&quot;Times New Roman&quot;,serif">Conclusion</span></strong></span></span></p>

<p style="text-align:justify"><span style="font-size:12pt"><span style="font-family:Aptos,sans-serif"><span style="font-family:&quot;Times New Roman&quot;,serif">CMR may exhibit a specific LGE distribution in patients with familial DCM/non-dilated LV cardiomyopathy according to the mutated gene. These findings support the correlation of genotype with LGE-phenotype in primary cardiomyopathy.</span></span></span></p>