1. Ischemic Complications
Limb Ischemia
- peripheral emboli (< 2 %) → resolution through combination of thrombolysis, catheter aspiration, angioplasty/stent as well as Fogarty maneuver
Pelvic Ischemia
- due to embolization or coverage of the internal iliac artery with endoprosthesis → gluteal claudication, rectal ischemia, erectile dysfunction, skin or muscle necroses
Prophylaxis:
- Use of endoprostheses with iliac side branches to maintain pelvic perfusion
Visceral Ischemia
- due to coverage of the inferior mesenteric artery and/or thromboemboli
- mostly colon affected, primarily descending colon and sigmoid
- Clinical presentation: bloody stools, diarrhea, abdominal pain, peritonitis
- Diagnostics: Rectosigmoidoscopy, possibly colonoscopy (Caution: increased risk of perforation!); Laboratory chemistry is nonspecific!
- Therapy: conservative-wait-and-see only for transient mucosal ischemia/severity grade A, otherwise location-dependent bowel resection, possibly Hartmann procedure
Prophylaxis
- preoperative exclusion of a significant stenosis of the superior mesenteric artery and the celiac trunk
Spinal Ischemia and Paraplegia (“ischemic spinal cord injury” – SCI)
- Cause: Reduced blood flow to the spinal cord due to endovascular overstenting of spinal cord-relevant arteries in combination with other risk factors such as perioperative hypotension, larger blood losses/anemia; especially in thoracic/thoracoabdominal procedures
If at least two territories of spinal perfusion are compromised, the probability of spinal ischemia increases.
- Clinical presentation: ranges from small transient sensory impairments to functional disorders of continence organs to complete paraplegia with lifelong bedriddenness and need for care
- Therapy: Increase in spinal perfusion pressure, e.g. pharmacological elevation of mean arterial pressure and placement of a cerebrospinal fluid drain to reduce the counterpressure of arterial perfusion in the cerebrospinal fluid spaces
Prophylaxis:
- Avoid intra- and postoperative hypotensive phases and after segmental artery occlusion maintain a mean arterial pressure of 80–90 mm Hg for at least 48 h
- Placement of a prophylactic spinal cerebrospinal fluid drain if at least two territories of spinal perfusion (see above) are impaired and cannot be reopened by revascularizing measures
- perioperatively sufficient central venous saturation (ScvO2) of ≥70 % and intraoperatively a central venous pressure (CVP) of ≤10 mm Hg, hemoglobin value ≥ 8 mg/dl or keep intraoperative blood loss as low as possible, cell saver
- postop. prompt extubation to assess neurological status, follow-up checks
2. Systemic Complications
- cardiopulmonary and cerebrovascular complications as well as contrast-induced nephrotoxicity
- acute coronary syndrome, myocardial infarction, pneumonia, cerebrovascular events, renal insufficiency -> adequate, interdisciplinary therapy
- preoperative evaluation: cardiac status, lung function, retention values
3. Post-Implantation Syndrome
- Incidence: 13 – 60 %
- Cause: inflammatory immune response with release of cytokines due to endothelial activation by the endograft material
- Clinical presentation: temporary, acute, flu-like symptoms, fever
- Laboratory: elevation of C-reactive protein (CRP), interleukin-6 and TNF-α during the first week after implantation; typically no leukocytosis and no pathogen detection
- Therapy: symptomatic (antipyretic measures, antibiotics are not indicated)
4. Pseudoaneurysms of the Access Vessels
- at the puncture site after percutaneous approach more common than after surgical exposure of the access vessel
- Incidence of pseudoaneurysms requiring treatment: 3 - 6%
- Therapy: ultrasound-guided thrombin injection into the aneurysm, possibly surgical repair, esp. for aneurysms > 1.5 cm
5. Endoprosthesis Migration
- Displacement of the endoprosthesis by more than 5–10 mm from the original position, usually caudally
- Incidence: 1 – 10 % (1-year follow-up after EVAR)
- Main cause of reinterventions for type I endoleaks (see below)
6. Kinking/Occlusion of the Endograft Limbs
- Incidence: 2 – 4 % of patients after EVAR
- Causes: progressive shrinkage of the excluded aneurysm sac with consecutive deformation of the endograft, pronounced aortic neck angulation, narrower diameter of the distal aortic neck, which can lead to compression of the prosthesis limbs
- Clinical presentation: intermittent claudication, also acute leg ischemia
- Therapy: placement of bare-metal stents or additional stent grafts within the original endograft; for acute occlusion recanalization with thrombolysis and subsequent stent implantation
7. Material Fatigue
- Cause: fractures of the stent struts, tears in the endograft material, loosening of Prolene sutures that attach the endograft material to the stent struts
- Consequence: Type I or Type III endoleaks (see below)
8. Endograft Infection
- Incidence after EVAR: 0.4 – 3 %
- Lethality 20 – 50 %!
- Risk factors: age, diabetes, obesity, malnutrition, gangrene/ulcer, duration of preop. hospitalization, op duration, inguinal access, blood loss, reinterventions, lymphoceles, hematomas, seromas, wound healing disorders, wound infections
- variable clinical presentation: relatively mild findings (elevation of inflammatory parameters), back pain, febrile infections up to dramatic courses with active bleeding/perforation, erosions of neighboring organs with fistula formations
- Therapy: broad-spectrum antibiotics immediately after diagnosis; no pathogen detection in blood culture → Vancomycin + agent against gram-negative pathogens (e.g. ceftriaxone, fluoroquinolone or piperacillin-tazobactam), otherwise according to resistogram; for persistent or recurrent infection after/or despite antibiotics → open surgical prosthesis explantation
9. Endoleaks
- Definition: persistent blood flow in the aneurysm sac after complete endograft placement
- most common complication after EVAR
- Classification:
- Type I and Type III endoleaks are associated with a higher risk of aneurysm rupture → prompt intervention recommended
- Diagnostics: CT, MRI, contrast-enhanced color-coded duplex sonography
- Therapy:
