St. Jude Medical (St. Paul, Minnesota), reported a new data analysis from the CHAMPION clinical trial that evaluated outcomes in a subgroup of patients with renal dysfunction (kidney failure). The CHAMPION trial looked at the safety and effectiveness of the CardioMEMS HF System for patients with New York Heart Association (NYHA) Class III heart failure (HF) who had been hospitalized for HF in the previous 12 months.

"When we take care of these patients many of the drugs that we use can pose a threat to renal functions or kidney functions,"Philip Adamson, co-principal investigator of the CHAMPION trial, told Medical Device Daily. "What we wanted to do in this analysis was answer the question does pulmonary pressure monitoring help us when patients have chronic kidney disease."

He added, "in those patients that had chronic kidney disease we had the same effect of using pressures to monitor their volume and guide medical therapy as those who had preserved renal function. The clinical question is, what do we do with the patients kidneys that don't work well when we're trying to pull volume off of them? We're always trying to balance between how much water patients have in them and are we damaging their kidneys."

The subgroup data analysis of 297 patients followed for 18 months, presented during the Heart Failure Society of America (Chevy Chase, Maryland) (HFSA) 18th annual scientific meeting in Las Vegas, looked at the potential benefit for patients with NYHA Class III HF and chronic kidney disease (CKD) using the CardioMEMS system to measure PA pressure without adversely affecting renal function. These data show that management based on PA pressure reduced HF hospitalization in this patient population by 42% compared to the control group and did not adversely affect renal function.

"We found that managing their HF syndromes, using the pressures from the sensor actually reduced hospitalizations significantly compared to the patients in the control group with chronic kidney disease and the chronic kidney disease patients in the treatment group had about the same results as those without chronic kidney disease," he said. "So what we discovered is that when we're able to manage these patients guided by the pressures, we're able to preserve kidney function; we're able to appropriately dose diuretics without worsening their underlying kidney problem and that resulted in significant reduction of hospitalizations."

The CardioMEMS system uses a miniaturized, wireless monitoring sensor that is implanted in the pulmonary artery (PA) during a minimally invasive procedure to directly measure PA pressure. Measuring PA pressure allows clinicians to proactively manage treatment for patients with worsening HF before visible symptoms, such as weight and blood pressure changes, occur. The system allows patients to transmit PA pressure data from their homes to their healthcare providers, who then manage appropriate medication changes to reduce the likelihood of hospitalization.

Adamson told MDD that the results give a definitive answer in using the device to help with chronic kidney disease function. He noted that there was really no need for additional testing given how strong the results of the test were.

"I think it answers the question," Adamson said. "I think those patients were included in the trial on purpose and were effectively evaluated. As a subgroup we sought to identify their experience and see if it was similar to the whole cohort and we found it was."

The device was developed by CardioMems (Atlanta). St. Jude gained access to the technology shortly after CardioMEMS received approval for it in May (Medical Device Daily, May 29, 2014). St. Jude had acquired 19% of CardioMEMS in September 2010 for $60 million. St. Jude ended up paying $375 million for the remainder of the company.

Nearly three years ago, the device was shot down at an advisory hearing in 2011. The application re-appeared at the circulatory systems advisory panel in 2013, however, leaving FDA with enough feedback to approve the device,

The CardioMEMS HF System is an innovative technology that helps physicians proactively manage their heart failure patients without adversely affecting the kidneys," said Mark Carlson, CMO for St. Jude Medical. "This analysis and others demonstrate our commitment to investing in clinical research that provides physicians with data to improve patient care." //