“The benefit was seen across the range of ejection fractions; that’s very important,” commented , director of advanced heart failure at George Washington University in Washington and a designated discussant for Dr. Shavelle’s report. “The safety seemed very good, and the efficacy was consistent” with prior reports. “There also was high compliance. The key to success is the structure” of patient management, Dr. Pangroth said. “The data are limited by who is monitoring patients and their data and how much of that contact influences patient outcomes.”
That final comment by Dr. Panjrath highlighted the biggest caveat that heart failure clinicians have raised about judging the efficacy of CardioMEMS. To achieve clinical efficacy, the implanted device requires diligent, virtually daily interrogation and data transmission by the patient, assessment of a large amount of data for each patient by the patient’s clinical team, and responsiveness by the patient to medication adjustments directed by the clinical team to deal with episodes of rising PA pressure.
“The device itself has no benefit. It’s the actions prompted by the device that have benefit,” noted, professor of medicine and chief of cardiology at Northwestern University in Chicago and a second designated discussant for the report.
Dr. Shavelle agreed that for the CardioMEMS device to have an impact, one basic requirement is to identify patients who will cooperate with data collection and transmission and also with changes in their medications that are sent to them in response to PA pressure changes. This means selecting patients who appear to have problems with volume overload, including prior hospitalizations for decompensation, and patients who are comfortable interacting with their clinical-care providers. It also means excluding patients who are too sick to benefit from this intervention. He estimated that at his center more than 95% of class III heart failure patients who qualified for inclusion in the post-approval study by clinical criteria were also judged reasonable recipients of the device based on their willingness to cooperate with this system. He also estimated that at the University of Southern California the heart failure clinical team is now caring for about 150 patients with a CardioMEMS device implanted.
Another concern is teasing apart the specific benefit of collecting and using PA pressure data from the contact that the clinical team maintains with CardioMEMS patients.
“If nurses are contacting patients more often, is it the device or the communication? We need to look at that very carefully in a study that had no control group,” Dr. Yancy said in an interview. Contact with a nurse “is the best thing you can do for heart failure patients.”
Dr. Shavelle countered that several reports from past studies that assessed case management and regular monitoring of and contact with heart failure patients but without PA pressure data failed to showed any consistent benefit to patients.
“If you pick the right patients, CardioMEMS works. There is no question in my mind that the device works,” Dr. Shavelle said in an interview. “If you pick the wrong patient, who will not send the data or follow dose changes, then it won’t work.”
The study was sponsored by Abbott, the company that markets the CardioMEMS HF System. Dr. Shavelle has been a consultant to and speaker on behalf of Abbott Vascular and he has received research funding from Abbott Vascular, Abiomed, Biocardia, and V-Wave. Dr. Yancy had an unspecified financial relationship with Abbott Laboratories. Dr. Panjrath had no disclosures.
SOURCE: Shavelle DM et al. American College of Cardiology annual meeting, .