Fig. 2From: Assessment of right atrium dysfunction in patients with obstructive sleep apnea syndrome using velocity vector imagingRight atrial strain rate determined by VVI. RA-SRs is the positive peak wave during ventricular systolic time (arrow). RA-SRe is the negative wave during early diastolic time (arrow). RA-SRa is the negative wave during late diastolic time (arrow)Back to article page