The Link between Right and Left Ventricular Systolic Performance at Rest and after Stress: Insights Into the Mechanism

BACKGROUND: Right ventricular (RV) systolic performance is more difficult for evaluation compared to the left ventricle (LV). Despite differences in structure, RV myocardial fibers are in continuity with those of LV. The aim is assessment of the effects of LV wall motion abnormalities (WMA) on RV systolic function at rest and after stress. METHODS: Fifty nine subjects, 15 with LV-WMA underwent dobuatmine stress echocardiography (DSE) studies using the usual protocol. Measurement of tricuspid annular plane systolic excursion (TAPSE), velocity (TASV), mitral annular plane systolic excursion (MAPSE) and velocity (MASV), were performed before and immediately after DSE studies. RESULTS: TAPSE was lower, in those with LV-WMA than in those without, both at rest 20.5 ± 4.8 mm versus 24.9 ± 4.7 mm, P = 0.015 and after DSE studies, 21.5 ± 5.6 mm versus 27.65 ± 5.7 mm, P = 0.005. DSE studies did not change TAPSE significantly in the presence of LV-WMA. TASV at rest in those with LV-WMA was 16.5 ± 2.7 cm/sec and similar to that in those without, 17.6 ± 3 cm/sec. In both groups the velocity increased after DSE studies, 23.25 ± 7.5 cm/sec, P = 0.01 with LV-WMA, and 27.5 ± 6 cm/sec, P = 0.0005, without LV-WMA. Despite similar TASV at rest, the TAPSE/TASV ratio, indicating duration of shortening, was lower (124 ± 21 msec) in subjects with of LV-WMA, than in those without (145 ± 27 msec), P = 0.0065, implying increased after load for RV longitudinal shortening in the presence of LV-WMA. CONCLUSIONS: TAPSE is lower at rest and after DSE studies in subjects with LV-WMA than in subjects without; however, DSE studies increase TPASE only in the absence of LV-WMA. TASV increases after DSE studies and is similar at rest in both groups with or without LV-WMA. It seems that LV-WMA increases after load to RV longitudinal motion.