Cerebral Vasospasm in Aneurysmal Subarachnoid Hemorrhage
Cerebral Vasospasm in Aneurysmal Subarachnoid Hemorrhage
Invasive interventional management strategies should be considered in aneurysmal SAH patients with new neurological deficits suspected to be the result of PHCV when the deficits are not reversed or incompletely reversed by medical therapy. In a recent consensus statement published by the Neurocritical Care Society, an international multidisciplinary panel agreed that endovascular intervention for symptomatic vasospasm may be indicated when medical management has failed or there is a concern for complications from medical management. With evidence that clinical improvement after endovascular therapy is most often achieved when treatment is initiated within 2 h of symptom onset, patients that are medically managed should be frequently reassessed. If a satisfactory response to medical therapy is not realized within 1 h of initiation, the decision for interventional management should not be delayed. In patients with unsecured ruptured aneurysms, in whom aggressive medical therapy carries a high risk of rebleeding from the index lesion, local treatment of remote vascular territories by IAVT or TBA may have a role. Interventional therapies should also be considered when medical therapy is contraindicated or beneficial to the patient but cannot be sustained because of cardiopulmonary, intestinal or other serious treatment related complications.
In many poor grade SAHs, it is difficult or impossible to clinically assess the patient's neurological deterioration. Consequently, it may be prudent to treat moderate to severe vasospasm revealed by non-invasive studies and confirmed by digital subtraction angiography (DSA). Transcranial Doppler studies and CT angiography are helpful in identifying patients with clinically silent PHCV. Cerebral perfusion imaging is being investigated as a diagnostic tool in this setting. Cerebral perfusion imaging is theoretically advantageous because it is sensitive to constriction of both proximal large vessels and small distal vessels. Recent data suggest that severe angiographic cerebral vasoconstriction, as determined by DSA, is an independent and reversible cause of cerebral infarction, neurological deterioration and poor clinical outcomes in SAH patients. Thus angiographic cerebral vasoconstriction may be considered an indication for invasive interventional management when clinical indicators are not reliable.
General Indications for Invasive Interventional Management
Invasive interventional management strategies should be considered in aneurysmal SAH patients with new neurological deficits suspected to be the result of PHCV when the deficits are not reversed or incompletely reversed by medical therapy. In a recent consensus statement published by the Neurocritical Care Society, an international multidisciplinary panel agreed that endovascular intervention for symptomatic vasospasm may be indicated when medical management has failed or there is a concern for complications from medical management. With evidence that clinical improvement after endovascular therapy is most often achieved when treatment is initiated within 2 h of symptom onset, patients that are medically managed should be frequently reassessed. If a satisfactory response to medical therapy is not realized within 1 h of initiation, the decision for interventional management should not be delayed. In patients with unsecured ruptured aneurysms, in whom aggressive medical therapy carries a high risk of rebleeding from the index lesion, local treatment of remote vascular territories by IAVT or TBA may have a role. Interventional therapies should also be considered when medical therapy is contraindicated or beneficial to the patient but cannot be sustained because of cardiopulmonary, intestinal or other serious treatment related complications.
In many poor grade SAHs, it is difficult or impossible to clinically assess the patient's neurological deterioration. Consequently, it may be prudent to treat moderate to severe vasospasm revealed by non-invasive studies and confirmed by digital subtraction angiography (DSA). Transcranial Doppler studies and CT angiography are helpful in identifying patients with clinically silent PHCV. Cerebral perfusion imaging is being investigated as a diagnostic tool in this setting. Cerebral perfusion imaging is theoretically advantageous because it is sensitive to constriction of both proximal large vessels and small distal vessels. Recent data suggest that severe angiographic cerebral vasoconstriction, as determined by DSA, is an independent and reversible cause of cerebral infarction, neurological deterioration and poor clinical outcomes in SAH patients. Thus angiographic cerebral vasoconstriction may be considered an indication for invasive interventional management when clinical indicators are not reliable.
