Primary Results of the Sensible Medical Innovations Lung Fluid Status Monitor Allows Reducing Readmission Rate of Heart Failure Patients (smile) Trial

Abstract

Background Acute decompensated heart failure (ADHF) is associated with a high rate of readmissions and mortality. Remote dielectric sensing (ReDS) fluid monitoring provides an accurate tool for non-invasive measurement of absolute lung fluid content, providing actionable information and a new tool for managing HF. Methods The SMILE trial was a prospective, multicenter, randomized clinical trial testing the hypothesis that post-discharge HF management guided by frequent in-home ReDS assessment is superior to usual care. Patients with a current hospitalization for ADHF, regardless of the LVEF, were enrolled in 43 US centers. Subjects randomized to the treatment arm were discharged home with the ReDS fluid monitor system and managed using ReDS measurements, according to protocol-defined algorithms. Control patients received usual care, without ReDS. The primary endpoint was recurrent (cumulative) ADHF hospitalizations, analyzed using the Andersen-Gill model with treatment group as the only covariate. Patients were followed for up to 9 months, until the last patient enrolled reached 3 months of follow-up. Results Between October 2015 and October 2017, 268 patients were randomized - 135 to treatment and 133 to control - and followed for 6.1±3.4 months. Patients were aged 68±12 years; 30% were women and 29% had LVEF≥40%. Pre-specified analysis of the per-protocol cohort demonstrated 21 readmissions in 15 ReDS patients compared to 43 readmissions in 34 control patients (HR 0.52, 95% CI [0.31-0.87], P=0.01) or a 48% readmissions reduction (Figure). Subgroup analysis by LVEF Conclusions The SMILE trial demonstrates a substantial reduction in recurrent ADHF hospitalizations and improvement in other outcome measures in recently discharged ADHF patients managed using daily ReDS assessment of absolute lung fluid content.