Page 56 - Assessing right ventricular function and the pulmonary circulation in pulmonary hypertension Onno Anthonius Spruijt

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p=0.030). Because NT-proBNP levels and the percentage-predicted diffusion capacity of carbon monoxide were not systematically available, the derived REVEAL score could not be calculated in the majority of patients at the time of follow-up.
Intervariability of echocardiographic measures
For RVFAC, the average difference in absolute measurement was 2.1±1.6%, with an ICC of 0.84; for TAPSE, the average difference in absolute measurement was 0.1±0.1cm, with an ICC of 0.93; and for RVMPI, the average difference in absolute measurement was 0.09±0.11, with an ICC of 0.85. The ICCs for maximal, minimal, and pre-atrial systole RA volumes were 0.95, 0.97, and 0.87, respectively. The ICC was 0.89 for total RAEF, 0.72 for active RAEF, and 0.84 for passive RAEF.
Discussion
Our study is the first to demonstrate that a simple score combining measures of RV systolic function, RA size, and SBP offered a good discrimination of outcome in patients with established PAH. Consistent with other studies, the results of our study highlighted that the quantitative metrics of right heart remodeling or function may simplify the risk stratification of patients with PAH [3, 18]. The REVEAL score and the NIH survival equation represent the 2 most validated survival scores in PAH [2, 5]. The NIH registry score relies on hemodynamic parameters, whereas the REVEAL registry score incorporates clinical, functional, and imaging parameters. Although our sample size was small, confidence in our results is provided by the fact that the right heart score correlated well with established outcome scores, the findings were validated in an independent cohort, and the results were consistent using different imaging modalities. In a recent publication, in a large series of patients with PAH, Fine et al. [18] showed that RV global longitudinal strain (RVGLS), log NT-proBNP levels, and NYHA functional class were independent correlates of clinical deterioration in patients with PAH. Consistent with the study of Fine et al. [18], our study also highlighted the importance of right heart function. In contrast, NYHA functional class and log NT-proBNP levels did not emerge as independent correlates of outcome due to their strong relationship with RV function and RA size; alternatively, our study may have been underpowered to assess their incremental value. In the REVEAL registry score, qualitative assessment of RV function was considered but did not emerge in the multivariate model; one can theorize, although not yet proven, that this may reflect the inter- laboratory variability in assessing RV function and the multiple grades of dysfunction considered (5 classes). With echocardiography, different metrics of RV systolic function have been considered,