Implantable CardioMEMS System Useful in Predicting Heart Failure Risk in PAH, Study Shows

Abbott’s CardioMEMS HF system — a wireless heart failure monitor — can be safely used to monitor blood flow (hemodynamics) changes and help predict the risk of heart failure in people with pulmonary arterial hypertension (PAH), results from a pilot trial show.

Additional studies in larger groups of PAH patients are still needed to confirm the potential of this wireless implantable system to monitor the effects of PAH treatment, to ultimately improve individuals’ outcomes and quality of life, the researchers said.

The trial results were reported in “Monitoring Pulmonary Arterial Hypertension Using an Implantable Hemodynamic Sensor,” published in the journal Chest. The study was led by researchers at Allegheny General Hospital in Pittsburgh, in collaboration with a team from Duke University.

PAH is a progressive disease that can lead to right heart dysfunction and failure. Close monitoring of blood pressure, and of the heart’s function, is necessary to ensure adequate early treatment, and prevent disease worsening.

CardioMEMS is the first wireless, implantable monitor that continuously measures pulmonary arterial pressure — an early indicator of the onset of worsening heart failure — approved by the U.S. Food and Drug Administration (FDA).

The system uses a small pressure sensor, which is permanently implanted in the distal pulmonary artery using a right heart catheterization procedure. The collected data is then transmitted wirelessly and stored in a secure website that clinicians can easily access.

Use of the CardioMEMS system has been demonstrated to significantly reduce hospitalizations due to heart failure. It also provided useful clinical information for helping improve patients’ quality of life.

“The development of ambulatory implantable hemodynamic monitors provides clinicians with remote access to daily cardiovascular measurements to monitor progression, guide therapy, and detect or prevent early decompensation,” the researchers said.

In this study, the investigators explored the safety and diagnostic potential of the CardioMEMS system in people with severe PAH who were hospitalized within the previous year due to right-sided heart failure.

They implanted the monitoring system in 26 patients, with a mean age of 51.3 years. Among these patients, 81% had marked limitations of physical activity — ranked as Class III in the New York Heart Association (NYHA) Functional Classification, the most commonly used system for classifying heart failure.

Results showed that, upon a mean follow-up period of 2.5 years, the system’s implantation protocol was safe.

Only one pre-implantation complication was reported, a microperforation of the pulmonary artery during preliminary vessel evaluation. After the sensor was implanted, no clinical complications or device safety issues were reported.

Direct CardioMEMS measurements provided information regarding patients’ systolic, mean, and diastolic pulmonary artery pressure. It also provided data on heart rate, cardiac output, right ventricular activity, and total pulmonary resistance, among other clinical parameters.

Collected data showed that the system was able to detect significant changes in the different hemodynamic parameters while patients were on PAH therapy. The system also accurately identified early hemodynamic changes, which further demonstrated that CardioMEMS could be used to monitor the efficacy of PAH therapy.

Evaluation of participants’ functional improvements over time — as determined by changes in the NYHA classification, exercise capacity, and patients’ reported quality of life — confirmed that they were associated with positive hemodynamic changes detected by the CardioMEMS system.

The team believes that “serial monitoring of hemodynamics over time” with this implantable system “is feasible and may provide added value compared to a single rest set of measurements made in the catheterization lab.”

Nonetheless, larger clinical trials are needed to compare CardioMEMS’s diagnostic potential with standard available methods, the researchers said. These studies on CardioMEMS are needed “before its widespread use to guide therapy in severe PAH patients with right-sided HF [heart failure]” can be implemented, they said.