BERLIN -- Among heart failure patients with moderate to severe disease, six months of monitoring with an investigational implantable sensor that measures pulmonary artery pressure was associated with a 30% relative risk reduction in hospitalizations for heart failure, researchers here reported.
After six months there were 83 hospitalizations for heart failure among the 270 patients randomized to treatment guided by hemodynamic measurements from the CardioMems Heart Sensor, compared with 120 heart failure hospitalizations in the 280-patient control arm (P<0.001), said William T. Abraham, MD, of Ohio State University.
Action Points
- The risk of hospitalization for heart failure was reduced among patients with moderate to severe disease after six months of monitoring with an investigational implantable sensor to measure pulmonary artery pressure.
- Note that this report describes an investigational device that is not FDA approved for clinical use.
- Note that this study was published as an abstract and presented at a conference. These data and conclusions should be considered to be preliminary until published in a peer-reviewed journal.
Abraham and his co-investigator, Philip B. Adamson, MD, of the Heart Failure Institute, at the Oklahoma Heart Institute in Oklahoma City, reported the findings from the phase III trial of the device at the Heart Failure Congress here.
Abraham said the data suggests that using the pulmonary monitoring device to guide treatment in just eight heart failure patients for six months would result in one less hospitalization for heart failure. The annualized relative risk reduction for heart failure admissions for the entire randomized follow-up would be 38% (P<0.0001). Treating only four patients for a year would reduce heart failure hospitalizations by one, Abraham added.
Robert M. Califf, MD, director of the Duke Translational Medicine Institute in Durham, N.C., said the CHAMPION results present "a solid basis from a randomized trial to use this technology. This is like the gauge in your gas tank -- it will be good for people to know that their fluids are at the right level."
But Califf who was asked by ABC News/乌鸦传媒Today to comment on the trial cautioned that "taking advantage of this advance will require a highly organized follow-up system with excellent communication."
Michael M. Givertz, MD, of Brigham and Women's Hospital, was also cautiously enthusiastic.
Givertz told ABC News/乌鸦传媒Today, that he and other heart failure specialists "have been waiting for an implantable device that offers true benefit to patients with heart failure."
The CHAMPION results, though preliminary, "suggest that using real-time pulmonary artery pressures to guide heart failure treatment reduces significant morbidity and may improve quality of life," Givertz added.
The study was designed as a single-blinded trial and all patients were implanted with the device, but only half had active monitoring with the device. Abraham said the investigators are now switching all control patients to active monitoring mode and all patients will continue to be followed.
The mean age of patients was 62 and roughly 30% of the patients were women.
The CardioMEMS sensor is a "wireless, battery-less, radiofrequency activated system," Abraham said. The objective is to achieve more precise hemodynamic management than can be obtained by relying on weight gain.
The device can be implanted in the right or left pulmonary artery branch with an average vessel lumen of 10 mm. The device "has an average implant time of seven minutes after catheterization," Abraham said.
All patients are put on clopidogrel plus aspirin for 30 days after implantation or are continued on previously-prescribed warfarin therapy, Adamson said.
The sensor, about the size of a paper clip, is activated when the patient places a wand-like device over the implant area, or lies on the wand. The wand activates the monitor by radiofrequency and pulmonary pressure readings are sent to the physician's office.
Increases in pulmonary pressures were treated with "neurohormonal, diuretic, and/or vasodilator therapies," Adamson said.
The primary efficacy endpoint was hospitalization for heart failure, but Abraham said in an interview that "all hospitalizations were reduced." This was an important consideration, since reducing heart failure hospitalizations while increasing hospitalizations for other causes would not yield a net benefit, he added.
Change in pulmonary artery pressures was a secondary efficacy endpoint and, here too, the results were impressive: the change from baseline in mean pulmonary artery pressure at six months measured as the mean area under the curve (AUC) decreased -156 in the active treatment arm versus an increase of 33 in the control group (P=0.008).
The hemodynamic monitoring pressure target values were:
- Pulmonary artery systolic pressure 15 - 35 mmHg
- Pulmonary artery diastolic pressure 8 - 20 mmHg
- Pulmonary artery mean pressure 10 - 25 mmHg
In an interview with 乌鸦传媒, Abraham called the results of the CardioMEMS Heart Sensor Allows Monitoring of Pressure to Improve Outcomes in NYHA Class III study (CHAMPION) a "grand slam home run," and the audience at the Berlin International Congress Center seemed to agree.
Henry Krum, MBBS, PhD, from Alfred Hospital in Melbourne, Australia, who served as discussant for the study, predicted that the CHAMPION study would immediately be regarded as a landmark trial and rather than marking an evolution in heart failure treatment "this may be the start of a revolution in management of heart failure patients."
The primary six month safety endpoint of the trial was freedom from device or system-related complications. There were no pressure sensor failures in the trial but there were a total of eight device or system-related complications, including two that occurred among 25 patients who consented but were never implanted with the device and three in each of the study arms.
Asked about the severity of those complications, Abraham said there were no serious adverse events -- no thromboembolic events such as stroke or myocardial infarction, but he did not elaborate.
Other secondary efficacy endpoints included the number of patients hospitalized for heart failure (54 in the treatment group versus 80 in the control group (P=0.022). Improvement in Minnesota Living with Heart Failure quality of life questionnaire (P=0.022) and increase in total number of alive days outside the hospital at six months, which was significant although the absolute difference was only a gain of about a day (P=0.024)
This article was developed in collaboration with ABC News. 
Disclosures
The CHAMPION Trial was sponsored by CardioMEMS Inc., of Atlanta, Georgia.
Abraham, Adamson, and other members of the CHAMPION committees and study group have received research grants and/or consulting fees from CardioMEMS.
Primary Source
Heart Failure Congress
Source Reference: Abraham WT and Adamson PB "Primary results of the cardioMEMS heart sensor allows monitoring of pressure to improve outcomes in NYHA class III heart failure patients (CHAMPION) trial" HFC 2010.