This case shows that angioplasty of an acute embolic occlusion of the MCA may represent the correct course of action to rapidly restore cerebral flow, especially when the thrombus extends beyond the lenticulostriate arteries and in patients with contraindications for thrombolysis or who are on anticoagulant therapy, since drug reduction would be detrimental to the patient's health.
Many studies have shown the feasibility of endovascular recanalization (PTA) in cases of acute stroke [8, 9].
Nakano et al. performed a retrospective comparison of 34 patients with acute MCA trunk occlusion who had been treated with direct PTA (followed by thrombolytic therapy in 21 patients) with 36 similar patients who had been treated with thrombolytic therapy alone [10].
Partial or complete recanalization was achieved in 91.2% of the first group as opposed to 63.9% of the second. Symptomatic intracerebral hemorrhage was observed in 2.9% versus 19.4%, and a good outcome (Modified Rankin Score ≤ 2) was reached in 73.5% versus 50% of the patients, respectively.
The majority of patients were treated with semicompliance balloons, typically coronary balloons, whereas Mangiafico et al. [11] and Lum et al. documented a series of 21 and 9 patients, respectively, treated with a combination of IA drugs and HyperGlide balloons.
The Multi MERCI trial, designed in part to test the performance of a new generation of thrombectomy devices, found an increased though not statistically significant rate of recanalization of intracranial vessels [3].
The potential risks associated with direct PTA include arterial rupture, spasm, and distal embolization [12–14].
In embolic occlusion, the balloon catheter should only penetrate the embolus, and dilatation force applied to the vessel wall is usually less than that used in the treatment of intracranial vascular stenosis [15].
Another potential drawback of this technique is the theoretical risk of occluding the lenticulostriate arteries because of the displacement of the clot. The use of thrombolytic agents, particularly local intra-arterial infusion of highly concentrated or high-dose thrombolytic agents into the ischemic tissue, may be the greatest risk factor in symptomatic hemorrhage.
For these reasons, mechanical clot removal without the use of thrombolytic agents may be the ideal treatment for acute ischemic stroke, especially in patients with a high hemorrhagic risk and increasing time from stroke onset, when the risk of hemorrhage increases.
In addition to clinical features, perfusion imaging techniques combined with MRI (magnetic resonance imaging) or CT are mandatory to recognize a clear demarcation of irreversible damaged infarcted and ischemic but still recoverable tissue, to accurately determine which patients may benefit from reperfusion, especially those with unknown time of stroke onset or who are outside the recommended 6-h time window for therapy [16–18].
The new MR techniques of diffusion-weighted and perfusion-weighted imaging, including in a diagnostic protocol of acute stoke patients, identified ischemic brain regions and detected impaired perfusion. CT is an essential diagnostic requirement in a stroke center to exclude patients with intracerebral hemorrhage and extensive demarcation of ischemic infarction.
In these instances, the presence of mismatch may justify mechanical revascularization in order to reduce potential hemorrhagic complications, as in our case.