Complications of various neurointerventional procedures and their management- Dr Pallav Jain

1. Complications of various
Neurointerventional procedures &
their management
PRESENTER- DR.PALLAV JAIN
DM RESIDENT(NEUROLOGY)
GMC,KOTA

2. Introduction
• Each neurointerventional procedure carries unique risks.
• Complications when anticipated, can frequently be avoided.
• Complications generally occurs while deviating from standard
procedures.

3. Complications in various procedures
Common are - Vascular access ,Contrast induced Nephropathy
Complications in common procedures
Diagnostic Angiography
Intracranial aneurysm
Acute ischemic stroke
Extracranial Carotid Angioplasty and stenting
Intracranial Angioplasty and stenting
Embolization procedures

5. Complications Related to Vascular Access
• Looking for peripheral pulsation pre- and postprocedure is always
recommended.
Common are-
• Groin hematoma
• Retroperitoneal hemorrhage
• Pseudoaneurysm
• Arteriovenous fistula.

6. Ideal site for groin puncture
• Incorrect site of the femoral
artery puncture is the most
common cause of these
complications.
• Puncturing below the femoral
bifurcation is usually the reason
for pseudoaneurysm

7. Reduce access-related complications
• Avoid areas of previous surgery or a lower extremity in which vascular repair has
been performed.
• Manual compression is given at the puncture site to avoid groin-site hematoma
and its related complications.
• Care should be taken to access the femoral artery at a compressible site below
the inguinal ligament
• Puncture site closure devices, including collagen plugs, percutaneous devices,
and external compression devices

8. Contrast induced Nephropathy
• Incidence of 5% in low-risk patients and 20 to 30% in high-risk
patients
Risk factors
• Contrast- related factors-high osmolar content, ionic contrast agents,
and high viscosity and high contrast volume.
• Patient-related-chronic kidney disease, diabetes mellitus, older age,
and other cardiovascular risk factors.

9. Prevention
• NSAIDS should be withheld for at least 24 hours before and after the
procedure
• Metformin should be avoided for at least 48 hours before the procedure
• Good hydration during the procedure
• Use of N-acetylcysteine or bicarbonate
• use of iso-osmolar and nonionic contrast

10. Complications of Diagnostic Angiography
Cerebral Angiography
• First step in performing neurointerventional procedures.
• Common complications-thromboembolism, air embolism from catheters and
wires resulting in cerebral ischemia.
• Disruption of atherosclerotic plaques, arterial dissection-ischemic events.
• Ischemic stroke may take the form of a large vessel occlusion or a small, distal
arterial branch occlusion.

11. In large studies,
• Transient neurological complications(0 to 0.7%)
• Permanent neurological complications(0 to 0.5%)
Quality improvement guidelines recommends
• Transient neurologic deficits(no more than 2.5%)
• Permanent neurologic deficits(no more than 1%)

12. Prevention of embolism
• A carefully titrated systemic heparin therapy to keep activated
clotting time (ACT) between 250 and 300.
• Aspirin and clopidogrel are routinely used for thromboembolism
prophylaxis in patients undergoing stent placement
• Air embolism-Making sure of an airless flush bag and line system at
the beginning of the procedure.

14. Management of ischemic stroke
• Prompt recognition of the event
Detection of a neurological change in the patient
By identifying a freshly occluded artery on the angiogram
• Intra-arterial thrombectomy or thrombolysis can then be undertaken.
• Situations in which deficit occurs in the postprocedure period
• Rapid imaging with CT or MRI may be helpful, f/b a return to the
angiography.

15. Treatment of Air embolism
• If large enough to be detected
fluoroscopically, vessel is easily accessible,
aspirate using microcatheter and flush the
vessel with heparinized saline to break up the
remaining bubbles.
• Quick and readily available methods
Use of transcranial Doppler (to agitate and
break up bubbles)
Heparinization (to prevent clot from forming in
vessels stagnating from the air)
Administration of oxygen and induction of
hypertension

16. Endovascular Treatment of Intracranial Aneurysms
Complication rates for coiling of intracranial aneurysms- 8.4 to 18.9%.
Risk is increased in patients
• Subarachnoid hemorrhage
• With the use of balloon- and stent-assisted coiling
• Treatment of very small and very large aneurysms
• Performance by inexperienced operators

17. Aneurysm or Vessel Perforation
• Risk is 4.1% (ruptured) and 0.5%(unruptured)
• Higher in aneurysm < 4 mm.
• May or may not be obvious on fluoroscopy or angiography.
Clues to the occurrence of a perforation
• sudden elevation in intracranial pressure or blood pressure
• bradycardia, or a prolonged sinus pause
• sudden headache or a neurological change

19. Tips to avoid rupture
• An aneurysm can be entered with the microwire sheathed inside the
microcatheter, and this may reduce the risks of perforation.
• Distal curve in the microcatheter and microwire may reduce the
chances of impinging directly on the wall

20. Whenever a perforation is identified or suspected
• Perforating wire, catheter, or coil should be left in position
• Prompt guide catheter angiogram should be done.
• CT scan-more subarachnoid blood than is actually present.
• Heparin anticoagulation should be reversed with protamine.

21. • When possible, coils may be deployed to treat the perforation.
• Second microcatheter can be used to continue coiling the aneurysm
• Balloon catheter to occlude the parent vessel to reduce the bleeding.
• Parent vessel sacrifice by embolization may be necessary.

22. Thromboembolism
• Thrombus formation- Result from manipulation of catheters, wires, coils, or
balloons.
• Thrombi may be directly visualized with guide catheter angiogram as a filling
defect within the parent vessel, or as a distal vessel occlusion.
• Adjustment of the angiogram image during the capillary phase
• By increasing the contrast and reducing the brightness at the monitor
• Make the ischemic defect more apparent
• Help identify the territory of affected arteries.

23. • Thrombus formation during coiling is primarily mediated by platelet
aggregation.
• 1ST step- Abciximab and other antiplatelet agents.
• Mechanical thrombectomy can be attempted using a 2- or 4-mm
snare.
• Thrombolytic agents- Avoided, particularly in cases of ruptured
aneurysms

26. Coil Dislodgement and Embolization
• Appropriately sized initial framing coil is essential for successful embolization.
• Unstable or malpositioned coil- Herniate into the parent vessel or embolize
distally.
• Over packing of an aneurysm- Also dislodge previously released coils.
• Coil herniation- increased risk of flow compromise or thrombus formation in the
parent vessel
• Coil migration can result in distal ischemia.

27. What to do
• Attempt to be made for retrieving detached coils.
• If the coil cannot be safely retrieved or repacked into the aneurysm-
Stent or balloon assistance may also be used to reinsert herniated coils
into the aneurysm
• Long-term antiplatelet therapy is recommended.

29. Vessel Injury
• Intimal injury is likely underreported.
• The vertebral artery is at greater risk of injury.
• Vessel dissection is generally asymptomatic
• Increased risk of occlusive or thromboembolic complications.
Imaging- Injury in the form of a double lumen or intimal flap in arterial
dissection.

31. Management of arterial dissection
• Dual antiplatelet therapy with aspirin 325 mg and clopidogrel 75 mg daily.
• For flow limiting injury, anticoagulation with IV heparin or stenting may be
necessary
• Follow-up imaging at 3 to 6months
• 90% of dissections causing stenosis-interval resolution,50% of dissections causing
occlusion-interval recanalization
• Dual antiplatelet therapy may be discontinued at that time.

32. Vasospasm
• Most commonly following aneurysmal subarachnoid hemorrhage
• May also complicate other neurointerventional procedures.

33. Treatment of Vasospasm
Balloon angioplasty is used for symptomatic vasospasm affecting
intracranial arteries >1.5 mm in diameter
Tips for the avoidance of complications-
• Limiting treatment to only arteries that are relatively easy to access
with a balloon catheter
• Undersizing the balloon diameter to minimize risk of rupture

34. Pharmacological doses
For vessels that are not easily accessible or safely treated with a
balloon, intra-arterial injection of nicardipine or verapamil can be used.
Verapamil
Mix with heparinized saline to achieve a concentration of 1 g/mL and
infuse at the rate of 1 mg/min for 5 min. Reassess after 5 min. Inject a
maximum of 15 mg/vessel
Nicardipine/Nimodipine
Mix with heparinized saline to achieve a concentration of 0.1 mg/mL
and infuse 1 mg over 5 min. Inject a maximum of 5 mg/vessel.

36. Rehemorrhage after coiling
• Occurs in some 0.9% of cases within 30 days after the procedure.
• Early rehemorrhage-usually occurs in aneurysms that were
incompletely occluded after initial treatment.
• Late rehemorrhage typically occurs in aneurysms with recanalization.
• Need for routine surveillance of coiled aneurysms

37. Complications of Endovascular Treatment of Acute
Ischemic Stroke
Intra-arterial treatment -effective alternative for patients
• Who cannot be treated with IV alteplase
• Do not respond to treatment with IV alteplase.
Commonly used intra-arterial techniques
• Suction thrombectomy
• Stent-retriever (stentriever) thrombectomy.

38. Complication rates with thrombectomy for ischemic stroke
Procedure-related mortality ranging from 0 to 2%
Permanent neurological injury of 3 to 6.5%.
Main threat -intracerebral hemorrhage(4.9 to 10% )
• Common to see small regions of contrast extravasation in the affected
territory of the brain after mechanical thrombectomy
• Not be confused with intracerebral hemorrhage.

39. Tips for avoiding complications
• Meticulous attention to the patient’s neurological status during and
after the procedure
• Reversal of heparin for bleeding complications
• Adequate control of blood pressure.

40. Anaphylactoid reactions
• Well-recognized reactions to thrombolytic agents(2%).
• Presents with localized swelling of the tongue, lips, or oropharynx.
• Occurs within 6 hours of exposure.
• Elective oropharyngeal intubation for airway control.
• CT scan of the face-rule out tongue or oropharyngeal hemorrhage.
• High-dose dexamethasone and antihistamines may speed up resolution of the
angioedema

41. Complications of Extracranial Carotid Angioplasty and Stenting
• Occurrence of acute neurological change during procedure suggests
thromboembolism
• Angiogram- intraluminal thrombus or delayed contrast passage
through distal intracranial vessels, indicating a shower of emboli.

42. What to do when thromboemboli are identified
• Infusion of IV glycoprotein IIb/IIIa inhibitors such as abciximab.
• Mechanical thrombectomy
• Intra-arterial thrombolytics can also be used
May be less effective against the platelet-rich thrombi, also carry a risk
of ICH.

43. ICH in CAS
• New neurologic deficit, headache, and a Cushing response
(hypertension and bradycardia) should raise suspicion for ICH.
• Immediate head CT, sheath should be left in place.
• If ICH is identified, heparin anticoagulation is reversed,strict blood
pressure control.

44. Hyperperfusion syndrome
• Occur in up to 5% of CAS cases and is associated with ICH in 0.7%.
• Present with ipsilateral headache, nausea, seizures, or focal neurologic
deficit
• Without radiographic evidence of ischemia from 6 hours to 4 days
following CAS.
• Result from an abrupt increase in cerebral blood flow following CAS in the
setting of previous chronic hypoperfusion and impaired autoregulation.

46. Treatment
• Consists of strict blood pressure control
• Typically resolves without permanent deficit in the absence of
associated ICH.

47. Precaution during procedure
• Excessive dilation should be avoided as it also places the patient at risk of
bradycardia and hypotension.
• Operator should be prepared for the possibility of bradycardia and
hypotension
• Having IV atropine and dopamine prepared and ready to inject
immediately after angioplasty
• Particularly when dilating at the level of the carotid sinus.

48. Complications of Intracranial Angioplasty
and Stenting
Candidates for balloon angioplasty with or without stenting.
• Patients with symptomatic intracranial stenosis greater than 70%
• who have failed medical therapy may be
• Perioperative stroke rate(7.9%),perioperative death rate(3.4%)
• Vessel perforation, intraluminal thrombus, shower emboli, and
dissection.
• Angioplasty without stenting carries a 30% rate of restenosis at 3 and
12 months.

49. Tips for the avoidance of complications
• Minimalistic angioplasty to avoid artery rupture and dissection
• Using angioplasty alone without placement of a stent if the post
angioplasty angiogram shows significant improvement in the stenosis.

50. Complications of Embolization Procedures
Endovascular embolization is a versatile technique
• Intracranial and spinal tumors
• Arteriovenous malformations
• Arterio-venous fitulas

51. Retained Microcatheter
• Microcatheters may become trapped by both adhesive and nonadhesive liquid
embolic material.
• A retained microcatheter may be retrieved by administering continuous, gentle
traction on the device for 5 to 10 minutes or more.
Additional techniques
Using a monorail snare technique to grasp the trapped catheter
Advancing an intermediate catheter over the trapped microcatheter to apply
countertraction.
Patients should be kept on aspirin indefinitely if a retained microcatheter is left in
place.

52. Hemorrhage
• Hemorrhage of tumors can occur during or after embolization
• Due to infarction of the tumor with hemorrhagic transformation.
Precautions to be taken
• Minimized by avoiding overly ambitious embolization of large tumors.
• Prepared for the possibility of urgent craniotomy and resection of the tumor if
necessary.

53. AVM rupture
Due to occlusion of draining veins without adequate disruption of feeding
arterial flow
Precautions-
• Medium and large brain AVMs should not be completely embolized in a
single session
• Complete occlusion carries a higher risk of hemorrhage.

54. Postembolization Edema or Hemorrhage
Normal perfusion breakthrough syndrome
• Significant cerebral edema occur following occlusion of high-flow fistulas, AVMs,
pial AVFs, or tumors
• Abrupt occlusion of a longstanding arterio-venous shunt exposes vessels with
disturbed auto-regulation to increased flow
• Resulting in hyperemic cerebral edema and the potential for hemorrhage.

55. Patients who are thought to be at risk
• May be treated with dexamethasone before and after the procedure
• Indomethacin may be used to induce cerebral vasoconstriction.
• Strict control of blood pressure is essential

56. Embolization of Unintended Targets
• Inadvertent embolization of the brain, retina, or cranial nerves can
occur.
• Reflux of embolic material in a retrograde direction may occur,
causing the embolic material to spill into collateral vessels.
Precautions-
• Identify potential dangerous collaterals prior to embolization
• Super selective, high magnification angiogram to identify collaterals
to the brain or eye is essential.

57. Risk of reflux can be minimized
• Mixing the embolic material with iodinated contrast material and
doing the injection under fluoroscopic guidance
• The injection should be stopped and aspiration through the
microcatheter should be performed whenever reflux of contrast
material is observed.

58. Conclusion
• Endovascular therapies has advanced rapidly since its inception.
• Still whenever complications occur, significant morbidity and
mortality are associated.
• A thorough knowledge of the procedures, hardwares,knowledge
about complication avoidance will help in reducing these adverse
events.

59. Refrences
• Girish Rajpal,Complications and Avoidance in Neurointerventional Surgery 2018
• Rakesh Khatri ,Complications of Neuroendovascular Procedures and Bailout
Techniques 2016
• Matthew C. Davis,Clinical Presentation, Imaging, and Management of
Complications due to Neurointerventional Procedures 2015
• P.MORRIS,Practical Neuroangiography 3rd E d i t i o n,2014
• www.uptodate.com
• Bradley 7th edition

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