TABLE 2.

Circular RNAs (circRNAs) that have biomarker potential in pulmonary arterial hypertension (PAH)

circRNA	Expression level	Study size	Biomarker role	Biomarker type	Reference
circ_0068481	↑ in serum of IPAH patients	Healthy controls (n=82); IPAH patients (n=82)	Had higher specificity and sensitivity for predicting IPAH; associated with poor clinical outcomes	Diagnostic and prognostic	[71]
circ_0068481	↑ in serum of PAH patients	PAH(−) RVH(−) (n=52); PAH(+) RVH(−) (n=42); PAH(+) RVH(+) (n=38)	Correlated with prediction of RVH diagnosis in PAH patients	Diagnostic	[30]
circGSAP	↓ in PBMCs of IPAH patients	Healthy controls (n=30); IPAH patients (n=60)	Correlated with occurrence and poor outcomes of IPAH	Diagnostic and prognostic	[22]

IPAH: idiopathic pulmonary arterial hypertension; RVH: right ventricular hypertrophy; PBMC: peripheral blood mononuclear cell.