Repeat Catheter Angiography in Patients with Aneurysmal-Pattern Angiographically Negative Subarachnoid Hemorrhage

Area of Science:

• Neuroscience
• Vascular Surgery
• Radiology

Background:

• Subarachnoid hemorrhage (SAH) diagnosis can be challenging, with a notable proportion of patients presenting normal initial cerebral angiograms.
• Angiographically negative SAH (anSAH) patients, particularly those with aneurysmal-pattern SAH (aanSAH), generally have a good prognosis if no underlying vascular abnormalities exist.
• The detection rate of occult aneurysms in aanSAH cases varies significantly across existing studies.

Purpose of the Study:

• To determine the diagnostic yield of repeat digital subtraction angiography (DSA) in patients with aanSAH.
• To quantify the rate of occult aneurysm detection through serial DSA examinations.

Main Methods:

• A retrospective review of patients diagnosed with aanSAH after initial DSA screening was conducted at a single neurovascular center.
• A systematic review and meta-analysis of published studies on repeat DSA in aanSAH patients was performed.
• Pooled detection rates of aneurysms on second DSA were calculated using a random-effects model, with inter-study heterogeneity assessed.

Main Results:

• In the institutional cohort, 11.1% of aanSAH patients with at least two DSAs were found to have a cerebral aneurysm.
• The meta-analysis of 26 studies revealed a pooled rate of 10.4% for positive second angiograms in aanSAH patients.
• Significant inter-study heterogeneity was noted in the meta-analysis results (I² = 61.7%).

Conclusions:

• Approximately 10% of patients diagnosed with aanSAH have an underlying occult ruptured aneurysm.
• A second-look DSA is a valuable diagnostic tool and should be strongly considered for patients with aanSAH.
• Identifying these occult aneurysms is crucial for appropriate management and improving patient outcomes.