Non Invasive Lung IMPEDANCE Guided Preemptive Treatment in Chronic Heart Failure Patients: A Randomized Controlled Trial (IMPEDANCE HF Trial)
BACKGROUND Previous investigations have suggested that lung impedance (LI) guided treatment reduces hospitalizations for acute heart failure (AHF) A single blind 2 center trial was performed to evaluate this hypothesis (ClinicalTrials.gov NCT01315223) METHODS The study population included 256 patients from 2 medical centers with chronic heart failure and left ventricular ejection fraction =35% in New York Heart Association class II IV, who were admitted for AHF within 12 months before recruitment. Patients were randomized to a control group treated by clinical assessment and a monitored group whose therapy was also assisted by LI, and followed for at least 12 months. Noninvasive LI measurements were performed with a new high sensitivity device. Patients, blinded to their assignment group, were scheduled for monthly visits in the outpatient clinics. The primary efficacy endpoint was AHF hospitalizations; the secondary endpoints were all cause hospitalizations and mortality. RESULTS There were 67 vs 158 AHF hospitalizations during the first year (P .001) and 211 vs 386 AHF hospitalizations (P .001) during the entire follow up among the monitored patients (48 32 months) and control patients (39 26 months, P .01) respectively. During the follow up, there were 42 and 59 deaths (hazard ratio 0.52, 95% confidence interval 0.35 0.78, P .002) with 13 and 31 of them resulting from heart failure (hazard ratio 0.30, 95% confidence interval 0.15 0.58 P .001) in the monitored and control groups, respectively. The incidence of noncardiovascular death was similar. CONCLUSION Our results seem to validate the concept that LI guided preemptive treatment of chronic heart failure patients reduces hospitalizations for AHF as well as the incidence of heart failure, cardiovascular, and all cause mortality.
Journal of cardiac failure