Figure 1.

Right ventricular longitudinal systolic strain (RVLSS) pattern in a patient with scleroderma-associated pulmonary arterial hypertension before (A) and after 36 weeks (B) of upfront treatment with ambrisentan and tadalafil. Longitudinal strain measures the percentage systolic shortening of a specific region of interest (ROI, obtained by tracking the endocardial borders of the ventricle) relative to its original length and is expressed as a negative percentage. Global RVLSS was calculated as the average of basal, midventricular, and apical ROIs (9). Worsening strain refers to a less negative number (i.e., a lower absolute value) than expected for an ROI along the longitudinal axis, and improved strain refers to a more negative number (i.e., a higher absolute value). Focused view of the right ventricle is demonstrated in the left panels. The right ventricular free wall is divided into three color-coded wall segments that correspond to strain curves shown on the adjacent curves: basal in red, midventricular in light blue, and apical in yellow. The numbers in the black circles represent the values of regional longitudinal strain for each segment. The interventricular septum has been excluded from the analysis. The right panels demonstrate strain curves for each segment of the right ventricular free wall (basal in red, midventricular in light blue, and apical in yellow). The dashed red curve represents the average value of the three segments. The dashed yellow line indicates the time (msec) of peak systolic strain during the cardiac cycle. The x-axis measures the time (msec). Cardiac cycle is timed based on EKG tracings, shown in green.