End points that are repeatable and sensitive to change are important in pulmonary arterial hypertension (PAH) for clinical practice and trials of new therapies. In 42 patients with PAH, test-retest repeatability was assessed using the intraclass correlation coefficient and treatment effect size using Cohen's d statistic. Intraclass correlation coefficients demonstrated excellent repeatability for MRI, 6 min walk test and log to base 10 N-terminal pro-brain natriuretic peptide (log 10 NT-proBNP). The treatment effect size for MRI-derived right ventricular ejection fraction was large (Cohen's d 0.81), whereas the effect size for the 6 min walk test (Cohen's d 0.22) and log 10 NT-proBNP (Cohen's d 0.20) were fair. This study supports further evaluation of MRI as a non-invasive end point for clinical assessment and PAH therapy trials. Trial registration number NCT03841344.
- imaging/CT MRI etc
- primary pulmonary hypertension