Scleroderma clinical trials consortium classification criteria for systemic sclerosis heart involvement

Systemic sclerosis-associated heart involvement (SHI) is an enigmatic disease manifestation associated with high mortality. The Scleroderma Clinical Trials Consortium (SCTC) Cardiac Working Group developed SHI classification criteria to enable systematic investigation of this condition.

An international, interdisciplinary working group was assembled. Using consensus methods and existing literature, provisional SHI classification criteria items were developed. Continuous consensus exercises and a discrete choice experiment were performed to reduce items and derive individual item weights. The sensitivity and specificity of the classification criteria were tested in an independent cohort (n = 168) of SHI (cases) and non-SSc heart disease (controls).

The working group agreed that the SCTC SHI Classification Criteria should identify the direct effects of SSc on the heart and exclude the complications of other SSc manifestations or cardiac comorbidities. The final classification criteria include 23 items measuring cardiac fibrosis, inflammation, arrhythmias and small vessel vasculopathy. No single item is pathognomonic for SHI, with a requirement for the presence of abnormalities across multiple histopathological, imaging, serological, and imaging domains to be present to secure a diagnosis. A classification criteria score of ≥11 identified SHI with a sensitivity of 78% and specificity of 96%, with an area under the curve of 0.87 (0.80-0.93). This threshold correctly identified >90% of cases of SHI.

The newly derived SCTC SHI Classification Criteria have high sensitivity and specificity for SHI. Application of these criteria will enable standardized classification of patients in studies to facilitate future investigation of this important disease manifestation.