First experience using intraoperative contrast-enhanced ultrasound during endovascular aneurysm repair for infrarenal aortic aneurysms.
BACKGROUND
Endovascular aortic repair (EVAR) has become an additional treatment option for patients with infrarenal aortic aneurysms and suitable aortic morphology. However, endoleaks are commonly encountered and represent a relevant risk for secondary treatment failure. In addition, impaired renal function or allergic reactions to intravascular iodine application might represent exclusion criteria for conventional infrarenal endovascular aortic repair using intraoperative angiography with iodine contrast media. Real-time contrast-enhanced ultrasound (CEUS) with a low mechanical index (MI) is a promising method recently introduced for follow up after endovascular infrarenal aortic repair.


METHODS
In this study, intraoperative CEUS using SonoVue as ultrasound contrast agent was evaluated in 17 patients for localization of the proximal infrarenal landing zone, the distal iliac fixation area, and identification of endoleaks in patients suitable for endovascular aortic repair with an infrarenal aortic neck > or =10 mm and non-aneurysmal common iliac arteries. For comparison, 20 patients were treated by conventional EVAR using intraoperative fluoroscopy and iodine contrast media.


RESULTS
Intraoperative application of contrast-enhanced ultrasound (iCEUS) for identification of the infrarenal landing zone and proximal stent graft release was achieved in 14 out of 17 patients (82.4%), as verified by intraoperative angiography or postinterventional imaging. Intraoperative CEUS-assisted visualization of the distal fixation area proximal to the level of the iliac bifurcation was achieved in 89.3% (25 out of 28 iliac arteries examined) in comparison to intraoperative angiography or postinterventional CEUS, computed tomography (CT), or magnetic resonance (MR) angiography. Three selected patients having contraindications for iodine-based contrast media were treated by iCEUS-assisted EVAR without the use of any iodine contrast during fluoroscopy. Time for exposure to intraoperative radiation, volume of contrast medium used, and the number of intraoperative angiographies and postinterventional CT or MR angiographies were significantly reduced in the iCEUS-assisted EVAR group in comparison to conventional endovascular aortic treatment (P < .002 or less for all parameters). Intraoperative application of CEUS detected more endoleaks than conventional EVAR (8/17 vs 4/20; P = .08) treated by proximal stent graft extension in one symptomatic patient with a type Ia endoleak.


CONCLUSIONS
Intraoperative CEUS-assisted EVAR in patients with infrarenal aortic aneurysms represents a new option for intraoperative visualization of aortoiliac segments required as proximal or distal fixation zones and identification of endoleaks, especially in those patients with contraindications for usage of iodine-containing contrast agents, in association with a reduction of iodine contrast media used and radiation exposure during fluoroscopy.
Kopp
Reinhard
R
Department of Abdominal and Vascular Surgery, Klinikum Harlaching, Staedtisches Klinikum Munich, Munich, Germany. reinhard.kopp@klinikum-muenchen.de
Zürn
Werner
W
Weidenhagen
Rolf
R
Meimarakis
Georgios
G
Clevert
Dirk A
DA
D000368:Aged; D017130:Angioplasty / Q000009:adverse effects / Q000379:methods*; D017544:Aortic Aneurysm, Abdominal / Q000000981:diagnostic imaging* / Q000601:surgery*; D019917:Blood Vessel Prosthesis Implantation / Q000009:adverse effects / Q000379:methods; D016009:Chi-Square Distribution; D015331:Cohort Studies; D003287:Contrast Media; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007430:Intraoperative Care / Q000379:methods*; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000453:epidemiology / Q000503:physiopathology; D011336:Probability; D011446:Prospective Studies; D012077:Renal Artery; D018570:Risk Assessment; D015607:Stents; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D018615:Ultrasonography, Doppler, Color / Q000379:methods
D003287:Contrast Media