An enhanced device for transluminal retrieval of vascular stents without surgical procedures: experimental studies.
BACKGROUND
Although efforts have been focused on developing endovascular procedures by which intravascular devices such as stents could be effectively deployed, few data exist regarding devices for the nonsurgical retrieval of deployed stents. Therefore, we designed to enable retrieval of deployed stents without a surgical procedure.


METHODS
The device consisted of four components: ultra-low profile forceps with 2.0 mm in diameter, conducting shaft with 1.8 mm in diameter, control handle by which the forceps is opened or closed, and a covering sheath. This device was designed to advance into the vessel lumen along a 0.014-inch guidewire by over the wire fashion.


RESULTS
The forceps could firmly catch nonexpanded as well as expanded tubular-type stents with open cells in an in vitro model that was 4.0 mm in diameter. Then, we used this device in porcine renal arteries with 2.5-5.0 mm in diameter. At first, a fragmented 0.014-inch guidewire could be safely removed without vessel damage that was confirmed by intravascular ultrasound. This device could successfully remove four of five inappropriately and 11 of 14 appropriately deployed stents. Under these conditions, intravascular ultrasound demonstrated minor vessel wall dissection in two-third of cases.


CONCLUSIONS
These results demonstrate that the present device can be used for transluminal removal of foreign bodies such as nonexpanded as well as expanded stents in acute phase. Further miniaturization may enable using this type of device in the renal as well as coronary arteries.
Tsuchida
Masayuki
M
From the Division of Cardiovascular Medicine, Kanazawa University Graduate School of Medicine, Kanazawa, Japan.
Kawashiri
Masa-Aki
MA
Uchiyama
Katsuharu
K
Sakata
Kenji
K
Nakanishi
Chiaki
C
Tsubokawa
Toshinari
T
Takabatake
Shu
S
Konno
Tetsuo
T
Ino
Hidekazu
H
Yamagishi
Masakazu
M
D017222:Angioplasty, Balloon, Laser-Assisted / Q000295:instrumentation* / Q000379:methods; D000818:Animals; D003331:Coronary Vessels; D004867:Equipment Design; D005240:Feasibility Studies; D005547:Foreign Bodies / Q000628:therapy*; D005548:Foreign-Body Migration / Q000628:therapy; D006801:Humans; D015607:Stents / Q000009:adverse effects*; D013525:Surgical Instruments; D013552:Swine; D018084:Ultrasonography, Interventional