Association between myocardial involvement and subclinical left ventricular dysfunction in patients with systemic...

Myocardial involvement frequently occurs in patients with systemic sclerosis (SSc), leading to myocardial tissue changes and subclinical ventricular dysfunction. This form of primary cardiac involvement is one of the major determinants of mortality in SSc and may eventually progress to overt heart failure. To date, the pathophysiology and subsequent subclinical myocardial dysfunction in asymptomatic patients with SSc have not been extensively described. This study aimed to assess subclinical myocardial deformation and tissue abnormalities in asymptomatic patients with SSc using non-contrast cardiac magnetic resonance (CMR) feature tracking and native T1 mapping, and to explore the relationship between native T1 values and myocardial strain.

The patients with SSc and age- and sex-matched healthy controls (HCs) underwent non-contrast CMR. Myocardial strain parameters and myocardial native T1 values were measured and compared between the HCs and patient subgroups based on skin involvement and disease duration. The association between the myocardial strain parameters and myocardial native T1 values was analyzed using Pearson's or Spearman's correlation and multivariate regression models.

A total of 44 patients with SSc and 22 HCs were enrolled in the study. The patients with SSc had significantly lower absolute longitudinal peak strain (-17.5%±3.0% vs. -18.9%±2.3%, P=0.030) and peak diastolic strain rate (0.9±0.2 vs. 1.1±0.3 1/s, P=0.025) than the HCs, after adjustment for age, sex, and body mass index. The patients with SSc had significantly higher myocardial native T1 values compared with the HCs (1,278.4±59.7 vs. 1,233.1±27.9 ms, P<0.001). The myocardial native T1 values demonstrated moderate correlations with the longitudinal strain parameters (|r|=0.40-0.56) in the patients with SSc, but this association did not persist after adjustment for confounders in multivariate regression models. No significant differences were found in the myocardial strain parameters and myocardial native T1 values between the patient subgroups (all P>0.05).

Reduced absolute myocardial longitudinal strain and elevated myocardial native T1 values in patients with SSc indicate myocardial dysfunction and tissue impairment. These findings suggest that CMR may serve as a valuable tool for characterizing early alterations of the heart and optimizing the clinical management of patients with SSc.