Risk assessment tool implementation in congenital heart disease associated pulmonary arterial hypertension
Authors: Yaylali Y , Yagmur B , Sinan U Y , Meric M , Basarici I , Kilickiran-Avci B , Senol H , Nalbantgil S , Kucukoglu M S , Ongen Z 
Published: October 2021

Abstract

Background
Risk assessment is recommended for patients with congenital heart disease associated pulmonary arterial hypertension (CHD-PAH). Patients in intermediate or high risk may need intensified therapies to improve their survival.

Purpose
To compare an abbreviated version of the risk assessment strategy proposed by the current European PH guidelines, noninvasive French model, and an abridged version of the REVEAL 2.0 risk score calculator, REVEAL Lite 2.

Methods
We enrolled a mixed prevalent and incident cohort of patients with CHD-PAH from 6 PAH centers from January 2006 to December 2019 (n=126). Noninvasive French model comprising WHO functional class (FC), 6-minute walk distance (6 MWD), and N-terminal pro–brain natriuretic peptide (NT-pro BNP) or BNP was used. REVEAL Lite 2 includes FC, systolic blood pressure, heart rate, 6MWD, BNP/NT-pro BNP, and estimated glomerular filtration rate. Patients were grouped into three categories according to the number of non-invasive low-risk criteria (French model) and REVEAL Lite 2 scores. Risk was calculated based on the last available assessment at 12 months' follow-up, starting from enrollment. Kaplan-Meier (KM) survival was assessed in patients in each risk group with all-cause mortality as the end point. Log-rank test was used to compare estimates.

Results
The mean age was 32±16 years at diagnosis. The mean follow up was 99.41±58.2 months. 32 patients had died. Most patients were Eisenmenger Syndrome (39.4%) and simple defects (19.7%). Most patients had received monotherapy (74.5%). 66.6% of patients were WHO FC I–II, 29.3% III, and 3.9% IV (Table). Both models effectively discriminated risk in our cohort (p=0.0001). Patients achieving two or more noninvasive low-risk criteria or low risk category by REVEAL Lite 2 at follow-up had a significantly reduced risk of death. Figure demonstrates KM survival curves for noninvasive French model (A) and REVEAL Lite 2 (B). 51% of patients achieved 2 or more low risk criteria at follow-up. 56% of patients were in low risk at follow-up (REVEAL lite 2). The estimated survival rate at 5 years of patients meeting 2 and more low-risk criteria at follow-up was 100% vs. 86.8% for patients meeting 1 low-risk criterion and 59.6% for patients meeting 0 low-risk criterion. The corresponding survival rate was 65% for high-risk patient, 76.2% for intermediate-risk patient, and 100% for low-risk patient (REVEAL lite 2) (p=0.0001 by log-rank test; Figure). REVEAL Lite 2 approximates noninvasive French model at discriminating among patients at low, intermediate, or high risk based on c-index.

Conclusions
Both noninvasive French model and REVEAL Lite 2 provide a simplified and robust method of risk assessment for CHD-PAH. This analysis also supports the value of goal-oriented treatment in CHD-PAH. Patients who have less than 2 low-risk criteria or who have not achieved low risk category at follow-up may benefit from escalation of their treatment regimen.

Funding Acknowledgement
Type of funding sources: None.