Geert Kleinnibbelink

Chapter 8 174 using the modified Bernoulli equation: TR maxPG = 4 x (TR Vmax). 2 Echocardiographic images were acquired specifically for offline speckle tracking analysis and construction of RV strain-area loops. This involved maintaining frame rates between 40 and 90 frames/ sec, depth to ensure adequate imaging of the chamber of interest, and compression and reject to ensure endocardial delineation. For methodology of derivations of strain-area loops, see Kleinnibbelink et al . 12 Statistical analysis was performed using SPSS Statistics 25 (SPSS Inc., Chicago, IL, VS). All parameters were visually inspected for normality. Continuous variables were reported as mean ± standard deviation (SD) and categorical variables were presented as proportions. Paired-sampled T-tests were used to compare baseline and follow-up measurements. For all tests, we assumed statistical significance at p < 0.05. Sub-analysis was performed by stratifying to clinically responders, defined by a decrease in NYHA classification, and clinically non-responders, defined by a similar or decreased NYHA classification, following 17 weeks of treatment with Selexipag compared to baseline. RESULTS Between 1 st June 2018 and 31 st December 2020, 12 consecutive patients with PAH started with Selexipag and participated in this study (59±18 years, 67% females, n=5 idiopathic PAH, n=5 PAH associated with connective tissue disease, n=2 PAH associated with congenital heart disease). A total of 4 participants dropped out (n=2 due to side effects, n=1 follow-up performed using non-compatible echomachine, n=1 lung transplantation). Eight participants (60±16 years, 6 females) completed the study protocol (n=3 idiopathic PAH, n=4 PAH associated with connective tissue disease, n=1 PAH associated with congenital heart disease) ( Table 1A ). At a cohort level, NYHA classification, 6MWT, NT- PRoBNP andMDRD-GFR did not significantly change following 17 weeks of treatment with Selexipag. Also, conventional structural and functional indices as well as characteristics of the RV strain-area loop did not significantly change following 17 weeks of treatment with Selexipag ( Table 1A , Figure 1A ). At an individual level, stratification toNYHAclassification revealed three clinical responders (65±15 years, 2 females, n=3 idiopathic PAH) and five clinical non-responders (57±18 years, 4 females, n=4 PAH associated with connective tissue disease, n=1 PAH associated