1409Use of phenomapping to determine response of treatment by sacubitril/valsartan in patients with heart failure with reduced ejection fraction
Authors: Godet M , Raitiere O , Chopra H , Guignant P , Fauvel C , Gaudin K , Eltchaninoff H , Beuer F 
Published: October 2019

Abstract

Background
Treatment by sacubitril/valsartan decreases mortality, improves KCCQ score and ejection fraction in patients with heart failure with reduced ejection fraction (HF REF), but there is currently no data to predict response to treatment.

Purpose
The purpose of our work was to assess whether unbiased clustering analysis, using dense phenotypic data, could identify phenotypically distinct HF-REF subtypes with good or no response after 6 months of sacubitril/valsartan administration.

Methods
A total of 78 patients in NYHA functional class 2–3 and treated by ACE inhibitor or AAR2, were prospectively assigned to equimolar sacubitril/valsartan replacement. We collected demographic, clinical, biological and imaging continuous variables. Phenotypic domains were imputed with 5 eigenvectors for missing value, then filtered if the Pearson correlation coefficient was >0.6 and standardized to mean±SD of 0±1. Thereafter, we used agglomerative hierarchical clustering for grouping phenotypic variables and patients, then generate a heat map (figure 1). Subsequently, participants were categorized using Penalized Model-Based Clustering. P<0,05 was considered significant.

Results
Mean age was 60.4±13.4 yo and 79.0% patients were males. Mean ejection fraction was 29.3±7.0%. Overall, 16 phenotypic domains were isolated (figure 1) and 3 phenogroups were identified (Table 1). Phenogroup 1 was remarkable by isolated left ventricular involvement (LVTDD 64.3±5.9mm vs 73.9±8.7 in group 2 and 63.8±5.7 in group3, p<0.001) with moderate diastolic dysfunction (DD), no mitral regurgitation (MR) and no pulmonary hypertension (PH). Phenogroups 2 and 3 corresponded to patients with severe PH (TRMV: 2.93±0.47m/s in group 2 and 3.15±0.61m/s in groupe 3 vs 2.16±0.32m/s in group 1), related to severe DD (phenogroup 2) or MR (phenogroup 3). In both phenogroups, the left atrium was significantly enlarged and the right ventricle was remodeled, compared with phenogroup 1. Despite more severe remodeling and more compromised hemodynamic in phenogroups 2 and 3, the echocardiographic response to sacubitril/valsartan was comparable in all groups with similar improvement of EF and reduction of cardiac chambers dimensions (response of treatment, defined by improvement of FE +15% and/or decreased of indexed left ventricule diastolic volume −15% = group 2: 22 (76%); group 3: 18 (60%); group 1: 9 (50%); p=0.17; OR group 2 vs 1: OR=3.14; IC95% [0.9–11.03]; p=0.074; OR group 3 vs 1: OR=1.5; IC95% [0.46–4.87]; p=0.5)). The clinical response was even better in phenogroups 2 and 3 (Group 2: 19 (66%); group 3: 21 (78%) vs group 1: 9 (50%); p=0.05).
Heat map

Conclusion
HF-REF patients with severe diastolic dysfunction, significant mitral regurgitation and elevated pulmonary hypertension by echocardiographic had similar reverse remodeling but better clinical improvement than patients with isolated left ventricular systolic dysfunction.