Unmasking the Hidden Threat: The Role of Left Ventricular Subendocardial Involvement in Autoimmune Rheumatic Disease.

Background: Late gadolinium enhancement (LGE) has been found in patients with autoimmune rheumatic disease (ARD). However, the prognostic implications of some specific LGE patterns in ARD patients remain unclear.

Purpose: To investigate the prevalence and prognostic significance of left ventricular (LV) subendocardium-involved LGE (LGEse) in a cohort of ARD patients.

Materials and methods: This retrospective study evaluated 176 patients diagnosed with ARD with clinically suspected cardiac involvement between 2018 and 2023. LV LGEse was defined as LGE involving the LV subendocardium that did not correspond to a coronary vascular distribution. The endpoints included a composite of cardiac death, heart failure-related admission, cardiogenic shock, and appropriate pacemaker or implantable cardioverter-defibrillator therapy.

Results: Of the 176 consecutive patients, LV LGEse was observed in 22 patients (13%). During a median follow-up of 776 days (interquartile range, 395-1405 days), 20 patients (11%) experienced a composite endpoint. Compared with those without LV LGEse, the LV LGEse group had a greater proportion of men (64% vs. 14%; p < 0.001), lower LV ejection fraction (50% vs. 60%; p = 0.001), greater LV end-diastolic volume index (78 vs. 75; p = 0.043), and more adverse outcomes (32% vs. 8%; p = 0.005). In the univariable and multivariable Cox regression analyses, the LV LGEse showed independent prognostic value. In the sensitivity analyses, the prognostic difference in terms of LV subendocardial involvement remained.

Conclusion: In our cohort, LV subendocardial involvement, an underrecognized LGE pattern, was observed in 13% of all patients with autoimmune disease and indicated a worse prognosis.