What are the common causes of infarct after stenting and coiling in a post-aneurysmal ruptured Subarachnoid Hemorrhage (SAH)?

Common Causes of Infarct After Stenting and Coiling in Post-Aneurysmal Ruptured SAH

Thromboembolic complications are the most common cause of infarcts after stenting and coiling procedures in patients with aneurysmal subarachnoid hemorrhage (aSAH), particularly in patients with poor clinical grade and aneurysms with large dome-to-neck ratios. 1

Primary Mechanisms of Infarction

Thromboembolic Complications

• Intraprocedural thrombus formation at the aneurysm base or distal artery during stent deployment 1, 2
• Postprocedural ischemia within 24 hours of treatment, presenting as new symptomatic deficits with corresponding hypodensities on CT imaging 1
• Higher risk with stent-assisted coiling compared to primary coiling alone, with reported rates of clinically significant thromboembolic events in 6% of patients 2
• Risk factors include poor clinical grade (WFNS IV-V) and aneurysms with larger dome-to-neck ratios 1

Vasospasm-Induced Cerebral Infarction

• Occurs in approximately 17.7% of aSAH patients and increases the odds of poor outcome by a factor of 5.2 3
• Significantly associated with:
  • Admission WFNS grade IV-V 3
  • Fisher CT group 3-4 (significant subarachnoid blood) 3
  • Middle cerebral artery aneurysm location 3

Technical Complications

• Higher incidence of technical complications with clipping (19%) versus coiling (8%) 4
• Incomplete aneurysm obliteration, which occurs more frequently with coiling (42% of cases) compared to clipping (19%) 4
• Stent-related complications including stent migration, malposition, or incomplete deployment 2

Antiplatelet Therapy Considerations

• Dual antiplatelet therapy is typically required for stent-assisted coiling, which increases hemorrhagic risk in the setting of acute SAH 2
• Clinically significant intracranial hemorrhagic complications occur in approximately 8% of patients undergoing stent-assisted coiling 2
• External ventricular drain (EVD)-related hemorrhages occur in about 10% of patients with EVDs who undergo stent-assisted coiling 2
• Evidence does not support that antiplatelet therapy during or after endovascular coiling improves outcomes in aSAH patients 5

Procedural Considerations

• Stenting of ruptured aneurysms is associated with increased morbidity and mortality (Class III, Level C) 4
• Y-stent assisted coiling for wide-necked ruptured aneurysms carries specific risks:
  • In-stent thrombus formation in 16.6% of cases 6
  • Procedural ischemic events in 13.3% of patients 6
  • Periprocedural asymptomatic intracranial hemorrhage in some patients 6

Prevention Strategies

• Complete obliteration of the aneurysm whenever possible is recommended to reduce complications (Class I, Level of Evidence B) 4
• Multidisciplinary decision-making involving both experienced cerebrovascular surgeons and endovascular specialists to determine the optimal treatment approach (Class I, Level of Evidence C) 4
• For patients with ruptured aneurysms of the posterior circulation that are amenable to coiling, coiling is indicated in preference to clipping to improve outcome (Class 1, Level B-R) 4
• Careful consideration of patient-specific factors:
  • Endovascular coiling may be preferable in elderly patients (>70 years), those with poor-grade SAH (WFNS IV/V), and basilar apex aneurysms 4
  • Microsurgical clipping may be preferable for patients with large intraparenchymal hematomas (>50 mL) and middle cerebral artery aneurysms 4

Post-Procedure Management

• Maintenance of euvolemia and normal circulating blood volume is recommended to prevent delayed cerebral ischemia (DCI) (Class I, Level B) 4
• Induction of hypertension is recommended for patients with DCI unless blood pressure is elevated at baseline or cardiac status precludes it (Class I, Level B) 4
• Close monitoring for vasospasm using transcranial Doppler is reasonable (Class IIa, Level B) 4
• Perfusion imaging with CT or MRI can be useful to identify regions of potential brain ischemia (Class IIa, Level B) 4

Follow-up Recommendations

• Delayed follow-up vascular imaging is recommended for patients who undergo coiling or clipping, with strong consideration for retreatment if there is a clinically significant remnant (Class I, Level B) 4
• Immediate cerebrovascular imaging after aneurysm repair is generally recommended to identify remnants or recurrence that may require treatment (Class I, Level B) 4

Understanding these mechanisms and risk factors for post-procedural infarcts can help guide treatment decisions and improve outcomes in patients with ruptured aneurysms requiring endovascular or surgical intervention.