Biomedical Engineering Reference
In-Depth Information
6
EVAR Cost Benefit
Comparing EVAR with conventional surgery, the first is preferable due to the fact of
being less stressful and reducing significantly systemic complications [
16
], as well
as having lower costs of inpatient stay and less or no need for intensive care facilities
during recovery [
6
,
17
]. While a number of early studies appeared to support this
claim, nowadays, data shows otherwise [
16
]. Shorter stays at intensive care units
and the hospital, reduced use of blood, fewer laboratory studies and fewer resources
lead to cost savings, but later, additional costs exist for EVAR due to surveillance
procedures.
The durability of open surgery, established with long-term follow-up studies,
is excellent [
16
], so good that there is little or no requirement for long-term
surveillance. Hayter [
17
] compared both hospital and follow-up costs of patients
who had undergone EVAR or open surgery and concluded that EVAR costs were
higher. One of the justifications presented was the endograft's high price.
When EVAR was introduced, it was thought to be more economical than open
surgery because the price of the first stent-grafts was lower and the surveillance
costs were not included in the analysis. Nowadays, EVAR can be considered cost-
effective only for very elderly patients or those with a reduced life expectancy and
doubtful for young patients, those who would benefit more from the short hospital
stay and early return to full activity offered by open surgery.
Considering the longer life expectancies and the rising public expectations for
quality of life, EVAR is an attractive treatment. However, its cost-benefit relation can
be jeopardized by the requirement of long-term surveillance. In order to reduce and
even eliminate these exams, new surveillance technologies are being investigated
and the most promising technique identified thus far is remote pressure sensing [
9
].
The authors believe that including sensing capabilities in a stent-graft will benefit
EVAR's future. Yet, that may not be enough. Preliminary results of a recent survey
regarding the ideal features of a stent-graft show that attention should be given to
the devices adaptability and delivery profile.
7
Future Trends for Stent-Grafts
Innovations on mechanisms for pressure detection within the aneurysm sac are being
developed concurrent with novel architectures and materials for the construction of
stent-grafts. Two original proposals that indicate future alternatives for stent-graft
design are presented next.
7.1
Origami Stent-Graft
In 2006, Kuribayashi [
18
] described the design, the manufacture and the properties
of an origami stent-graft. The new device received this designation because the
paper folding patterns used in the Japanese art of origami was employed to fold it.