Page 53 - Assessing right ventricular function and the pulmonary circulation in pulmonary hypertension Onno Anthonius Spruijt

The strongest relationships were found with RVEDA index, RVESA index, RVFAC, TAPSE, RA size, active RAEF, and log NT-proBNP levels. In addition, New York Heart Association (NYHA) functional class, resting SBP, kidney function, low cardiac index on right heart catheterization, and PVRI were associated with outcome. Figure 4 presents the c-statistic of the RV and RA parameters, as well as their Kaplan-Meier survival curves from RVFAC and RA index categories. With the area-length method, volumetric measures of RA size or RAEF were not associated with significantly different c- statistics (p=0.79 and p=0.87, respectively). To minimize overfitting the multivariable Cox proportional hazards model, we only included 4 variables in the initial analysis (i.e., RVFAC, RA index, resting SBP, and NYHA functional class III and IV vs. I and II). The choice of variables was based on the following rationale: 1) RVFAC was more strongly associated with outcome than other RV functional parameters and was not collinearly related to RA size in contrast to RVEDA or RVESA; 2) RA size was more reproducible than active RAEF in our study population; 3) SBP was not collinearly related to RVFAC—in contrast, there was a moderate relationship between RV systolic pressure or relative RV systolic pressure and RVFAC (r=0.45; p < 0.001 and r=0.48; p<0.001); and 4) NYHA functional class was related to outcome in many previous studies. On multivariable analysis, RVFAC, RA size, and SBP were strongly and independently associated with outcome, as shown in Table 4 (both in continuous and categorical analyses). In the subgroup of patients for whom NT-proBNP level was available (n=79), NT-proBNP level was not retained in the multivariable model.
Chapter 3
HR 95%CI
0.6 0.4-0.7 1.4 1.1-2.8 0.7 0.5-0.9
3.4 2.0-7.75 3.0 1.3-8.1 3.3 1.5-9.4
p-value
<0.001 0.021 0.007
<0.001 0.009 0.002
Multivariable model – continuous RVFAC, per 5%
RAI, per 5cm2/m2
SBP, per 10mmHg
Multivariable model – categorical
RV systolic dysfuncti on per grade* Severe RAE, >16cm2/m2
SBP <110mmHg
adjusted for age and sex. RAE = right atrial enlargement; RH = right heart; other abbreviations as in Tables 1 and 2.
RH score (categorial) RH score, per grade
3.2 2.3-5.4
Table 4: Independent Correlates of the Composite Endpoint in the Derivation Cohort. *RV dysfunction was classified into normal (no dysfunction), mild, or moderate to severe according to the American Society of Echocardiography criteria. Model was
<0.001
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