Supplementary Material for: Right Ventricular Index for Risk Stratification of Patients with Pulmonary Arterial Hypertension
datasetposted on 12.07.2018, 09:30 by Sinning C., Harbaum L., Schrage B., Rübsamen N., Magnussen C., Waschki B., Kleemann W.H., Baaske K.M., Kögler M., Ojeda F., Fischer C., Benjamin N., Westermann D., Zengin E., Schäfer U., Egenlauf B., Klose H.F., Blankenberg S., Grünig E.
Background: Right ventricular (RV) dysfunction is a major prognostic predictor in pulmonary arterial hypertension (PAH). Objectives: The objective of this study was to assess the prognostic impact of a newly developed index merging haemodynamic parameters into 1 variable. Methods: We retrospectively assessed 2 cohorts of 248 patients (164 from Hamburg and 84 from Heidelberg) with invasively diagnosed PAH. During a median follow-up time of 3.6 years (3.1 and 4.0 years for Hamburg and Heidelberg, respectively), the composite endpoint of all-cause mortality and lung transplantation occurred in 57 patients (53 and 4 patients for Hamburg and Heidelberg, respectively). The RV index was developed in the Hamburg cohort and validated in the Heidelberg cohort: (right atrial pressure × pulmonary vascular resistance)/mixed venous oxygen saturation. Results: Patients with a high RV index had a higher incidence of the combined endpoint in Kaplan-Meier analyses in the Hamburg and Heidelberg cohort (p = 0.017 and p = 0.034, respectively). The calculated RV index cut-off value was 91 and identified patients with a worse outcome in the Hamburg cohort and showed a trend in the Heidelberg cohort (p < 0.001 and p = 0.089, respectively). The RV index in Cox regression hazard models was an independent predictor of outcomes after adjustment for sex and age in both cohorts (Hamburg: hazard ratio [HR] 1.26 [95% CI 1.08, 1.47], p = 0.0027; Heidelberg: HR 2.27 [95% CI 1.46, 3.51], p < 0.001). A nomogram based on these results allowed risk stratification. Conclusion: Merging 3 haemodynamic variables into 1 variable, the RV index increased the prognostic power up to an independent risk factor. The RV index is easy to calculate and allows the construction of a nomogram for an individualized risk assessment.