Pressure sensing is feasible for TAA


At the International Congress, in Phoenix, AZ, Dr Ross Milner, Emory University, GA, presented his initial (first in man) experience with the CardioMEMS pressure sensor during endovascular thoracic aortic aneurysm (TAA) repair.

The CardioMEMS is a non-invasive, sac pressurement system that is introduced (independently) at the time of the stent-graft and is compatible with all stent grafts. The CardioMEMS Endosensor is a small, biocompatible implant that is placed within the aneurysm sac during an endovascular procedure. Once inside the patient, aneurysm sac pressure can be wirelessly measured using radiofrequency (RF) energy and proprietary measurement technology.

Previously, results from the Acute Pressure Measurement to Confirm Aneurysm Sac EXclusion (APEX) trial have demonstrated that remote abdominal aortic aneurysm (AAA) sac pressure sensing is feasible and can be performed easily and safely. Moreover, pressure measurement is accurate, demonstrating that sac pressure decreases upon exclusion with the endograft and that the pressure continues to decrease over time, correlating with shrinkage of the sac.

Milner said that the pressure sensor assists with knowing whether you have appropriate exclusion of the aneurysm during the initial implantation so you should see a marked reduction in pulse pressure. However, he stated that thoracic aneurysms have unique characteristics and develop (if there are late issues) Type 1 or Type 3 endoleaks.

The first in man (FIM) experience for TAA was in July 2005, in Florinopolis, Brazil, and was performed by Milner and Dr Pierre Silveira. “At one month pulse pressure was 16, at three months 18 and at six months 6. What we found is that pulse pressure is the most significant measure of exclusion.”

In conclusion, Milner said that initial experience with the CardioMEMS remote pressure sensor for TAA is feasible and assists in knowing that there is appropriate exclusion of the aneurysm. In addition, he also said that use of the pressure sensor could limit follow-up to just a standard X-ray (not CT), reducing the need for contrast agents.

Finally, he announced that there is an FDA trial planned for assessing an indication for TAA pressure sensing.