Cardiomems Heart Failure Monitoring Sensor Is Safe and Reliable, Which Can Effectively Reduce the Ho

Heart failure affects the health of nearly 6 million Americans. It is a disease in which the heart cannot discharge enough blood to meet the body's needs under appropriate pressure. Cardiomems is a small sensor device, which is only the same size as a small paper clip. It can be directly implanted into the patient's pulmonary artery to connect the heart and lungs. In minimally invasive outpatient surgery, doctors implant sensors into the heart through the femoral vein of the groin. Once implanted, the device can detect the rise of pulmonary artery pressure, which is an early warning of the impending onset of pulmonary effusion and congestive heart failure, even earlier than the symptoms of shortness of breath or weight gain. Pulmonary artery pressure information is recorded and wirelessly transmitted from the patient's home to the security database, so that doctors can view the data in real time through the website and actively adjust the treatment plan to keep the patient's pulmonary artery pressure value at the target value.

According to the requirements of the U.S. Food and Drug Administration (FDA), this prospective open label trial was launched after approval to evaluate the effectiveness and safety of cardiomems sensor in clinical practice. The device was approved by FDA in May 2014 and is mainly used for patients with New York Heart Association (NYHA) grade III heart failure (usually the daily life of patients at this level has been limited) and patients hospitalized for heart failure in the previous year. The study involved 1200 patients in 104 clinical trial sites in the United States. The mean age of participants was 69 years, of which 38% were female, 17% were non white, 30% were patients with ejection fraction preserved heart failure (HFPEF), and 53% were patients with ejection fraction reduced heart failure (hfref).

"This trial has a very large number of subjects, including a large number of patients represented by women and ethnic minorities, which shows that the device is not only safe, but also effective in avoiding readmission," said Dr. David shavelle, the lead author of the study and an associate professor at the Keck School of medicine at the University of Southern California, "Our results further confirmed the feasibility of the concept of remote monitoring of pulmonary artery pressure. Pulmonary artery pressure can be used as another dimension for the evaluation of patients' lung volume status, so drug treatment can be adjusted in time to prevent hospitalization for heart failure in the later stage. These patients have a very high risk of hospitalization and complications, so this study has achieved an important breakthrough in the management of heart failure diseases 。”

The key point to check whether the treatment is effective is whether the hospitalization rate due to heart failure has decreased one year after the sensor is implanted compared with the previous year. Heart failure is one of the main reasons for hospitalization of people aged 65 and over. The patients in the trial were hospitalized for heart failure for 1.24 times in the year before the device was implanted, and decreased to 0.52 times in the year after the device was implanted. The researchers said that this means It means that the hospitalization related to heart failure decreased by 58%. The hospitalization rate of patients with the highest hospitalization rate (more than twice in the previous year) also decreased.

"Using this device can reduce the risk of hospitalization by more than half," shavelle said. "The hospitalization rate of patients in different groups has been reduced. We also verified that this treatment can also reduce the hospitalization rate of patients with HFPEF."

Regardless of the patient's ejection fraction, it can be divided into ejection fraction preserved heart failure (50% or higher, which is generally normal), ejection fraction reduced heart failure (less than 40%) or ejection fraction median heart failure (41 50%) , the sensor can effectively prevent hospitalization. Ejection fraction is one of the indicators to measure the degree to which the heart injects blood from the heart into the body. Women and racial / ethnic minorities also benefit significantly. The hospitalization rate of heart failure in women is reduced by 61% and that in blacks is reduced by 53%.

In addition, the hospitalization rate of patients with implantable cardioverter defibrillator (ICD) or cardiac resynchronization therapy defibrillator (CRT-D) and patients with ischemic or non ischemic cardiomyopathy decreased after using cardiomems sensor.

At the same time, the use of this device can also reduce the all-cause hospitalization rate of pneumonia, chronic obstructive pulmonary disease (COPD) or arrhythmia by 28%. Other analysis shows that after the implantation of the sensor, the comprehensive rate of hospitalization or death related to heart failure also decreased by 44%.

"If you can maintain a more normal ventricular filling pressure and less cardiac load, your body is unlikely to be seriously affected and you don't need to be hospitalized for other diseases, such as lung or liver diseases, which are affected by heart function," shavelle said, "We believe that using this sensor for monitoring by the care team can also encourage patients to follow their drug treatment plan and give them a sense of security, which is particularly important for patients who avoid hospitalization."

Of course, the cardiomems sensor has also achieved the expected safety goal: it will not be affected by the device or system related complications or sensor failure within one year. In order to evaluate the safety, researchers have been tracking whether there will be complications related to the device or system and Sensor failure. According to shavelle, according to these data, only four patients had complications related to the device or system, and only one sensor failure. On the other hand, 99.7% of the subjects had no complications related to the device or system and 99.9% had no sensor failure one year after the device was implanted.

At the same time, there is an ongoing study to evaluate the cardiomems sensor in other patients at risk of grade heart failure (NYHA grade II and IV) who have not been hospitalized.

Attachment: introduction of cardiomems device

The device consists of a sensor inserted through a venous catheter and an electronic system. The latter obtains and processes signals from the sensor, and then transmits the pulmonary artery pressure information to the safety database. According to the procedure, the patient wirelessly monitors his pulmonary artery pressure at home, and the data is immediately transmitted to the safety database, which can be monitored by doctors in real time through the cardiomems website.

Figure 1: transvenous catheter placement

Figure 2: the device includes two parts: sensor and transmission system

Figure 3: acquiring and processing signals from sensors and transmitting information

Figure 4: real time monitoring by doctors through cardiomems website