The long-term effect of a lung-ultrasound intervention on the risk for death, heart failure and myocardial infarction in dialysis patients

Extravascular lung water, a measure of fluid overload, is easily detected by lung ultrasound (US), a fast, easy-to-learn technique validated in dialysis patients [1]. Lung US is used for treatment monitoring in patients with decompensated heart failure [2, 3], and it is a powerful predictor of death and cardiovascular events in the dialysis population [4]. In the ‘LUng water by Ultra-Sound Guided Treatment (LUST) to Prevent Death and Cardiovascular Complications in High-Risk ESRD Patients with Cardiomyopathy’ trial (NCT02310061), a treatment strategy guided by lung US was not more effective than a usual care strategy in improving the primary endpoint of the study (a combination of death, heart failure and myocardial infarction) [5]. Since robust, long-term legacy effects of interventions targeting fluid volume status on major clinical outcomes in haemodialysis patients may emerge after the end of trials, we designed a post-trial, observational analysis extended up to 53 months (4.4 years). Since analyses by sex are important in clinical trials, as in the corresponding source trial, also in this study we performed effect modification analyses by sex and other major risk factors as a secondary endpoint.