In patients , global area strain correlated inversely with SDI ( r = -@ , P = @ ) , RV end-diastolic volume ( r = -@ , P = @ ) , and RV end-systolic volume ( r = -@ , P = @ ) and positively with EF ( r = -@ , P = @ ) , while RV SDI correlated positively with RV end-systolic volume ( r = @ , P = @ ) , pulmonary regurgitation fraction ( r = @ , P = @ ) , and QRS duration ( r = @ , P = @ ) and negatively with RV EF ( r = -@ , P = @ ) .