Usefulness of Respiratory Stability Time-Guided Management to Prevent Readmission of Chronic Heart Failure Patients...

Background: Telemonitoring aimed at detecting subclinical heart failure and facilitating medication up-titration offers a promising approach to reducing heart failure hospitalizations. Our team has recently developed a non-invasive metric called "respiratory stability time (RST)", which quantifies respiratory instability, a surrogate marker of subclinical worsening heart failure. A decrease in RST below 20 s predicts the onset of worsening heart failure within 28 days. However, the clinical utility of RST-guided management in reducing mortality and heart failure hospitalizations remains uncertain. Methods: The Innovative Tele-Monitoring Environment To Halt Ongoing Deterioration of Heart Failure-III (ITMETHOD-HF-III) is a non-blinded, interventional, multicenter, single-arm study. Eighty heart failure patients with a history of at least two prior hospitalizations for heart failure will be enrolled. After validating the robustness of RST measurements, participants will be monitored for 1.5 years through daily RST measurements. Mandatory up-titration of heart failure medications will be started if RST values decrease below 20 s for two consecutive days or decrease progressively below 30 s over 10-90 days from RST values above 45 s maintained for over 1 month, irrespective of the presence of heart failure signs/symptoms. Medication adjustment will continue until RST exceeds 30 s. The study will compare a composite endpoint of heart failure hospitalization and cardiac death between the present RST-guided group and a historical control group from the ITMETHOD-HF-II trial, in which management was based on patients' symptoms. Results: We anticipate that the precent ITMETHOD-HF-III study will demonstrate that mandatory, RST-guided heart failure management significantly reduces the incidence of the primary composite endpoint-heart failure hospitalization and cardiac death-compared with symptom-guided standard care in the historical control group (ITMETHOD-HF-II). Conclusions: The ITMETHOD-HF-III study aims to demonstrate the clinical efficacy of RST-guided management in reducing heart failure hospitalization rates and cardiac mortality by enabling early detection of subclinical heart failure and facilitating timely medication adjustments, irrespective of heart failure signs/symptoms. If successful, RST-guided management could establish a new standard for telemonitoring heart failure patients in outpatient settings.