DALLAS — Management of heart failure patients with data from an implanted device that continuously monitors hemodynamic pressures led to a 25% reduction in total days spent in the hospital among patients with class III heart failure in a controlled study with more than 200 patients.
“The number of days spent in the hospital for decompensated heart failure is the principal driver of cost for heart failure treatment, and this was significantly decreased,” Dr. William T. Abraham said at the annual scientific sessions of the American Heart Association.
Use of the device in both outpatients and in hospitalized patients with heart failure “may make episodes of decompensation less extreme, and may help get patients out of the hospital more quickly,” said Dr. Abraham, professor and director of the division of cardiovascular medicine at Ohio State University in Columbus.
The finding came from new analyses of data collected in the Chronicle Offers Management to Patients with Advanced Signs and Symptoms of Heart Failure (COMPASS-HF) trial, which tested the clinical impact of managing patients with intracardiac pressure data collected by the implanted Chronicle device. The device is made by Medtronic, which submitted an application for licensing to the Food and Drug Administration last August that was still pending in January.
The primary end point of the COMPASS-HF was reported last March at the annual meeting of the American College of Cardiology. Although patient management guided by pressure data obtained by the Chronicle device led to a 22% cut in the rate of heart failure-related hospitalizations and emergency department and urgent-care visits, the drop was not statistically significant. However, several secondary analyses also were positive in favor of the device, including a new set of secondary analyses presented by Dr. Abraham, who is a consultant and investigator for Medtronic and has received honoraria from the company for speaking.
He cautioned that the COMPASS-HF study was not designed to provide definitive answers to these secondary analyses, and therefore the findings must be considered exploratory.
In addition, researchers at Medtronic have revised the results presented by Dr. Abraham based on more comprehensive patient follow-up. The revised data showed that use of data from the Chronicle device cut the number of hospitalized days for heart failure by 20% instead of the 25% difference reported by Dr. Abraham. The 20% reduction is what was reported to the FDA, said Dr. David Israeli, director of marketing and business development for Medtronic in Minneapolis.
In the COMPASS-HF study, a total of 274 patients with advanced-stage heart failure underwent surgery to receive the subcutaneously-implanted, hemodynamic monitoring device. The intracardiac pressure information collected by the device was used by physicians to guide the management of 134 patients for 6 months. The pressure information was withheld from the treating physicians in the control group of 140 patients. All patients in the study also received optimal medical care based on clinical findings. The benefits of applying information collected by the Chronicle device were greatest in the 85% of patients who entered the study with New York Heart Association class III disease. Those with class IV disease had much less benefit.
The reduction in hospitalized days using data collected by the implanted device was more marked if the analysis excluded outlier patients with hospitalizations that extended beyond 30 days. With this exclusion, use of the Chronicle data cut the total number of hospitalized days by 42% for all patients in the study, and by 38% in the class III-only patients.
Another secondary analysis examined the impact of using data from the Chronicle device on the rate of prolonged or short hospitalizations for heart failure. Among the class III-only patients, use of Chronicle information was associated with an average rate of 0.19 long hospitalizations (more than 5 days) every 6 months, compared with a rate of 0.31 long hospitalizations every 6 months in the control group, a 40% decrease in favor of the device. Use of the device also was associated with a 0.28 rate of short hospitalizations (5 days or less) every 6 months, compared with a rate of 0.42 short hospitalizations every 6 months in the control group.
Despite the lack of a statistically significant positive result for the primary end point of the COMPASS-HF trial, the researchers who ran the study believe that the results demonstrate the device's efficacy.
“It's a positive study overall,” commented Dr. Robert C. Bourge, lead investigator for the study and professor and director of the division of cardiovascular disease at the University of Alabama, Birmingham.