To assess right atrial (RA) myocardial mechanics in pulmonary hypertension (PH) patients using two-dimensional speckle tracking imaging(2D-STI), and define the relationship between RA function and exercise capacity in PH patients.

Thirty-eight consecutive PH patients were studied and compared with a control group of 25 healthy volunteers. Peak atrial longitudinal strain (PALS) and strain rate of RA were measured in all subjects. PALS values were obtained by averaging all segments (global PALS) measured in the 4-chamber view.

RA PALS was significantly lower in PH patients than in controls, and gradually reduced with the development of cardiac insufficiency. A significantly postive correlation between global PALS and 6-minute walk distance was found(P=0.003). Furthermore, global PALS demonstrated the highest diagnositic accuracy (AUC of 0.979) and excellent sensitivity and specificity of 86.8% and 84.0%, respectively, to predict functional status using a cutoff value less than 38.08%.

RA deformation is significantly damaged in PH patients. RA reservoir function can be estimated using 2D-STI, and gradually decrease in PH patients with different WHO-functional class (WHO-FC). RA PALS is a powerful predictor of cardiac functional status and exercise capacity in PH patients.

Echocardiography; Hypertension, pulmonary; Atrial function, right; Speckle tracking imaging