ABSTARCT Objectives Myocarditis in systemic sclerosis (SSc) is associated with a poor prognosis. Cardiac Magnetic Resonance (CMR) is the non-invasive diagnostic modality of choice for SSc-myocarditis. Our study investigates the performance of the mapping techniques, included in the revised Lake Louise Criteria (LLC), for the identification of SSc-myocarditis. Methods CMR data (right and left ventricular function and morphology, early and late gadolinium enhancement [LGE], T2 ratio, and T1 mapping, extra-cellular volume [ECV] and T2 mapping) of SSc patients diagnosed with myocarditis were reviewed. Myocarditis was defined by the presence of symptoms of SSc-heart involvement with increased high-sensitive troponin T(hs-TnT) and/or NT-proBNP and at least an abnormality at 24 h-ECG-Holter and/or echocardiography and/or CMR. A p-value < 0.05 was considered as statistically significant. Results 19 patients (median age 54 [46–70] years; females 78.9%; diffuse SSc 52.6%; anti-Scl70 + 52.6%) were identified: 11(57.9%) had echocardiographic, and 8(42.8%) 24 h-ECG Holter abnormalities. All patients had at least one CMR abnormality: LGE in 18(94.7%), increased ECV in 10(52.6%), T2 mapping > 50ms in 15(78.9%). Median T1 and T2 mapping were 1085[1069–1110]ms and 53.1[52–54]ms, respectively. T1 mapping directly correlated with NT-proBNP(r = 0.620; p= 0.005), ESR(r = 0.601; p= 0.008), CRP(r = 0.685; p= 0.001) and skin score(r = 0.507; p= 0.027); ECV correlated with NT-proBNP serum levels(r = 0.702; p= 0.001). No correlations emerged between T2 mapping and other parameters. Ten patients satisfied the 2009 LLC, 17 the 2018 LLC. With the new criteria including T2-mapping, the sensitivity improved from 52.6% to 89.5%. Conclusion the CMR mapping techniques improve the sensitivity to detect myocardial inflammation in patients with SSc-heart involvement. The evaluation of T2 mapping increases diagnostic accuracy for the recognition of myocardial inflammation in SSc.

Primary heart involvement is frequent in systemic sclerosis, even though often sub-clinical, and includes cardiac abnormalities that are predominantly attributable to systemic sclerosis rather than other causes and/or complications. A timely diagnosis is crucial to promptly start the appropriate therapy and to prevent the potential life-threatening early and late complications. There is little evidence on how to best manage systemic sclerosis-primary heart involvement as no specific treatment recommendations for heart disease are available, and a shared treatment approach is still lacking. The objective of this review is to summarize the state of the art of current literature and the overall management strategies and therapeutic approaches for systemic sclerosis-primary heart involvement. Novel insights into pathogenic mechanisms of systemic sclerosis-primary heart involvement are presented to facilitate the comprehension of therapeutic targets and novel treatment strategies.