Newswise — A new implantable sensor is now providing minimally invasive internal pressure monitoring following endovascular abdominal aortic aneurysm repair (EVAR). Surgeons at the Mount Sinai School of Medicine are leading the way in the testing of internal pressure sensors after EVAR surgery. In a new study published in the Journal of Vascular Surgery, Dr. Sharif H. Ellozy and colleagues at Mount Sinai published their successful breakthrough showing their "continuing clinical experience with the use of a permanently implantable, ultrasound-activated remote pressure transducer." This development of remote pressure sensing technology and the successful implantation and testing of the device raises the promise of eliminating the need for an invasive measurement technique.
Over a 22 month period, 21 patients underwent EVAR of an AAA with implantation of a sensor exposed to the excluded aortic sac. At follow-up sac "pressures could be obtained at all visits for 15 of the 21 patients" by remote sensor. Other results included aneurysm shrinkage greater than 5mm in 50 percent of the patients and "no aneurysm enlargement was observed in any patient. Endovascular aneurysm repair results marked reduction of sac pressure in most patients. Patients with aneurysm shrinkage after EVAR have significantly lower mean pressure index: however, the absence of sac shrinkage does not imply persistent pressurization of the sac," the surgeons at Mount Sinai reported.
The build up of pressure is a major concern following the EVAR surgery. Post-operative monitoring is crucial for patients. Between 40-50% of patients who undergo the procedure develop a serious complication in which the aneurysmal sac is not entirely isolated, leading to recurrent pressurization of the sac called endotension or endoleaks. In the past, the only way to measure pressure was with direct puncture of the aneurysm sac and most recently CT angiography scans.
AAA is a ballooning of the abdominal aorta. Due to a progressive weakening of the vessel wall, AAAs gradually balloon, and if left untreated, the enlargement can lead to aortic rupture - fatal in nearly 80% of cases. In recent years EVAR, a less-invasive procedure of inserting an endovascular stent graft has become more customary than open abdominal surgery.
Ellozy and colleagues published their study "Abdominal aortic aneurysm sac shrinkage after endovascular aneurysm repair: Correlation with chronic sac pressure measurement" in the Journal of Vascular Surgery. (2006; 43(1): 2-6)
MOUNT SINAI SCHOOL OF MEDICINELocated in Manhattan, Mount Sinai School of Medicine is internationally recognized for ground-breaking clinical and basic-science research, and innovative approaches to medical education. Through the Mount Sinai Graduate School of Biological Sciences, Mount Sinai trains biomedical researchers with an emphasis on the rapid translation of discoveries of basic research into new techniques for fighting disease. One indication of Mount Sinai's leadership in scientific investigation is its receipt during fiscal year 2004 of $153.2 million. Mount Sinai now ranks 25th among the nation's medical schools in receipt of research support from NIH. Mount Sinai School of Medicine also is known for unique educational programs such as the Humanities in Medicine program, which creates opportunities for liberal arts students to pursue medical school, and instructional innovations like The Morchand Center, the nation's largest program teaching students and physicians with "standardized patients" to become not only highly skilled, but compassionate caregivers. Long dedicated to improving its community, the School extends its boundaries to work with East Harlem and surrounding communities to provide access to health care and educational programs to at risk populations.