AB1214 EARLY AND LONG-STANDING SYSTEMIC SCLEROSIS DIFFER FOR SERUM AUTOANTIBODIES AND CLINICAL CHARACTERISTICS PREDICTING PRIMARY HEART INVOLVEMENT AT CARDIAC MAGNETIC RESONANCE
Authors: M. De Santis, A. Tonutti, F. Motta, A. Ceribelli, S. Rodolfi, L. Monti, M. Francone, C. Selmi
Journal: Annals of the Rheumatic Diseases (2024)

<h3>Background:</h3> Primary heart involvement (pHI) constitutes a significant source of morbidity and mortality in patients with systemic sclerosis (SSc) and cardiac magnetic resonance (CMR) serves as the standard diagnostic tool<sup>[1]</sup> for myocardial inflammation and fibrosis. Predictors of SSc-pHI remain poorly defined, as does the clinical profile of this patient subgroup. <h3>Objectives:</h3> To analyze the clinical, serological, and imaging features of patients with SSc and CMR-confirmed pHI, and to compare patients with inflammatory vs. fibrotic myocardial lesions. <h3>Methods:</h3> In our retrospective cohort study, the signs of inflammatory myocarditis at CMR included increased T2 mapping native time, elevated T2 myocardial/skeletal muscle ratio, or the presence of areas of T2 TIRM. The presence of late gadolinium enhancement, as well as increased T1 mapping native time and extracellular volume in the absence of increased T2, suggested myocardial fibrosis. <h3>Results:</h3> Out of 350 SSc cases, 45 (13%) underwent CMR due to suspected pHI, defined by the presence of symptoms (palpitations, <i>angor</i>, dyspnea, syncope), elevated myocardial enzymes, or new-onset arrhythmia observed in the 24-hour Holter ECG. SSc-pHI was diagnosed in 37 out of 45 (82%) cases, and these patients had more frequently diffuse SSc (dcSSc) (32% vs. 0; p = 0.06), along with a lower prevalence of anti-topoisomerase-I (TOPO1 – 41% vs. 88%, p = 0.016; p = 0.024 at multivariable analysis). Moreover, increased serum CK-MB (30% vs. 0; p = 0.051) and troponins (32% vs. 0; p = 0.037) were associated with SSc-pHI (<b>Table 1</b>). Considering patients with CMR-confirmed SSc-pHI, a comparison was made between those with early (&lt; 3 years) and longstanding SSc (≥ 3 years; median disease duration at pHI diagnosis 10.5 years, IQR 8.8-12.3) (<b>Table 2</b>). Anti-TOPO1 was more common in early SSc with pHI (65% vs. 20%; p = 0.006), while anticentromere (24% vs. 60%; p = 0.026) and anti-SSA (0 vs. 25%; p = 0.027) were more prevalent in longstanding SSc. Patients with early SSc and pHI exhibited a higher skin score (median 8 vs. 4; p = 0.06) and a higher prevalence of interstitial lung disease (76% vs. 45%; p = 0.052), while myositis was more common in SSc patients with longstanding disease and pHI (0 vs. 20%; p = 0.051). Elevation of C-reactive protein (53% vs. 20%; p = 0.036) or CK-MB (58% vs. 24%; p = 0.057) predicted pHI in early SSc but not in longstanding disease; conversely, exertional dyspnea (24% vs. 55%; p = 0.052) was a predictor of pHI in longstanding disease but not in early SSc. T1/T2 mapping was available for 33 patients: sixteen (48%) patients (five of them with also LGE areas) had an increase in both T1 and T2 mapping native times, 9 (27%) had isolated T2 increase, 6 (26%) had isolated T1 increase, and 2 (9%) had only LGE. These four CMR clusters were not significantly or differently associated with clinical, laboratory, or cardiac functional alterations, maybe due to the small sample size. <h3>Conclusion:</h3> The diffuse cutaneous phenotype and increased serum myocardial enzymes predict pHI at CMR in patients with SSc. In early SSc, pHI is associated with anti-TOPO1, elevated skin score, C-reactive protein, and CK-MB. A CMR-based phenotyping of pHI SSc patients warrants further investigation. <h3>REFERENCES:</h3> [1] Bruni C, et al. JSRD. 2023. <b>Table 1.</b> Predictors of SSc-pHI confirmed at CMR. <b>Table 2.</b> Comparison between patients with early vs. longstanding SSc and CMR-confirmed SSc-pHI. <h3>Acknowledgements:</h3> <b>NIL.</b> <h3>Disclosure of Interests:</h3> Maria De Santis: None declared, Antonio Tonutti: None declared, Francesca Motta: None declared, Angela Ceribelli: None declared, Stefano Rodolfi: None declared, Lorenzo Monti: None declared, Marco Francone: None declared, Carlo Selmi AbbVie, Amgen, Alfa-Sigma, Biogen, Eli-Lilly, EUSA Pharma - Recordati, Galapagos, Janssen, Novartis, Octapharma, Pfizer, Recordati Rare Disease, SOBI, AbbVie, Amgen, Alfa-Sigma, Biogen, Eli-Lilly, EUSA Pharma - Recordati, Galapagos, Janssen, Novartis, Octapharma, Pfizer, Recordati Rare Disease, SOBI, AbbVie, Amgen, Janssen, Novartis, Pfizer.