For patients with heart failure, changes in pulmonary artery (PA) pressures are an early indication that their condition is worsening, even before they notice symptoms such as shortness of breath or weight gain.
Obtaining an accurate, early reading of PA pressure — the blood pressure in the pulmonary artery, which carries de-oxygenated blood to the lungs — can avoid rapid decline and help keep patients out of the hospital.
A recently FDA-approved device the size of a paper clip allows patients to measure their PA pressure at home and to send the reading to their physicians remotely. Vanderbilt Heart interventional cardiologists implanted this device, called CardioMEMS, in two patients last week.
The CardioMEM HF System features a small pressure-sensing device that is implanted directly into the PA during a minimally invasive procedure, enabling the patient to take PA pressure readings at home using a small bedside unit. PA pressure readings are then sent wirelessly to the health care provider, allowing adjustment of medication without the need for a hospital or clinic visit.
“With this device clinicians will be able to monitor PA pressures and proactively manage medications to improve quality of life and reduce readmissions,” said Connie Lewis, N.P., who monitors the readings, which are sent to a website, and follows the patients post-procedure.
Mark Glazer, M.D., and David Slosky, M.D., implanted CardioMEMS in the first two Vanderbilt Heart patients. Each procedure took about an hour.
The implantable sensor is permanently placed in the PA during a right heart catheterization procedure. The PA sensor has a thin, curved wire at each end. This sensor does not require any batteries or wires.
The delivery system is a long, thin, flexible tube (catheter) that moves through the blood vessels and is designed to release the implantable sensor in the far end of the pulmonary artery.
“We do right heart catheterizations every day. This is a variant of that procedure and involves imaging the PA so we can locate where the device is going to be implanted. So, it’s a slightly more complicated extension of what we routinely do,” Glazer said.
Patients go home the day of the procedure. They are instructed to set up the wireless transmitter at their bedside. They lie on a special pillow that obtains and sends PA pressure and heart rate measurements to a secure database for review and evaluation by the patient’s doctor.
The CardioMEMS device is for New York Heart Association (NYHA) Class III heart failure patients who have been hospitalized for heart failure in the previous year.
“We are trying to manage these patients medically as best we can. This technology will allow us to do that better. In fact, we have been monitoring patients’ heart rhythm changes for many years wirelessly, so this is a significant advance on that technology to allow actual pressure measurements to be done automatically,” said Daniel Lenihan, M.D., who along with Joann Lindenfeld, M.D., director of Heart Failure and Transplant, and Kelly Schlendorf, M.D., MHS, care for patients through the Advanced Heart Failure program.
