Endovascular treatment of acute embolism of the major cerebral arteries. The value of balloon disruption of the embolus

Abstract

This study evaluated: 1) the effect of recanalization on changing clinical outcome, 2) the relationship between dose of Urokinase (UK) and incidence of recanalization and intracranial haemorrhage, and 3) the efficacy and feasibility of balloon disruption (BD) in the treatment of acute cerebral embolism. Sixty-one patients with acute embolism of the major cerebral arteries treated by endovascular approaches over the past nine years were retrospectively evaluated. Among them, 30 cases were treated by BD alone or in conjunction with intra- arterial fibrinolysis in the last five years. The other 31 cases, mostly treated in the first four years, were treated with intra-arterial fibrinolysis alone and were used as controls to evaluate the efficacy of BD. Control angiography was performed just after the reperfusion procedure to evaluate the degree of recanalization. Angiographic responses were graded using modified Thrombolysis in Myocardial Infarction (TIMI) criteria. Clinical outcome was evaluated using modified Rankin Scale (mRS) score at the time of discharge. Thirty-six of the 61 patients (59.0%) achieved high-grade recanalization (TIMI grade 3). Significantly more patients attained favorable outcome (mRS score 0-1) in the high-grade recanalization group than the low-grade recanalization group (41.7% vs. 16.0%, p < 0.05). Concerning patients treated with BD, significantly more patients attained good recanalization and significantly more patients were ambulatory (mRS score 0-3) than those treated with intra-arterial fibrinolysis alone (76.7% vs. 41.9%, p < 0.01; 70.0% vs. 41.9%, p < 0.05, respectively). A significantly lower dose of UK was used, and relatively less intracranial haemorrhage was seen in patients treated with BD than those treated with intra- arterial fibrinolysis (194,000 +/- 191,000 units vs. 388,000 +/- 231,000 units, p=0.001; 16.7% vs. 38.7%, p=0.055, respectively). Concerning morbidity and mortality of BD, there was one death caused by dissection of the M2 portion of the middle cerebral artery (MCA) that happened during BD on a distally migrated embolus. Although no conclusions can be drawn from our study, a favorable outcome for acute embolism of the major cerebral arteries is expected by attaining good recanalization. In addition, BD is an effective technique that can achieve high-grade recanalization alone, or reducing the dose of fibrinolytic agent.

Figure 1

Neurological and survival prognosis on discharge. A) Significantly more patients were discharged alert in the highgrade recanalization group than the low-grade recanalization group (p< 0.005). B) Significantly more patients attained favorable outcome (mRS score 0-1) in the high-grade recanalization group (p< 0.05),and significantly more patients were ambulatory (mRS score 0-3) in the high-grade recanalization group (p< 0.005). Significantly fewer patients died during hospitalization in the high-grade recanalization group (p< 0.05).

Figure 2

Relationship between dose of UK and incidence of haemorrhagic infarct and recanalization. A) Degree of recanalization in IA group. There was no significant difference in dose of UK between 13 cases with high-grade recanalization and 18 cases with low-grade recanalization (p = 0.135). B) Haemorrhagic infarct among 50 patients treated with UK. A significantly higher dose of UK was given to 6 patients with intracranial haemorrhage than the other 44 patients (p<0.01). The cut-off level seems to be around 400,000 Units.

Figure 3

Results by recanalization procedure. A) Significantly more patients attained high-grade recanalization in the BD group than the IA group (p<0.01). B) Significantly more patients were discharged alert in the BD group (p<0.01). C) Although there was no significant difference in favorable outcome (mRS score 0-1) on discharge (p = 0.142), significantly more patients were ambulatory (mRS score 0-3) in the BD group (p < 0.05).

Figure 4

Difference in UK dose by recanalization procedures. A significantly lower dose of UK was given in the BD group (p = 0.001).

Figure 5

Illustrative case. 73-year-old male with old myocardial infarction and congestive heart failure suddenly presented with left hemiplegia and disturbance of consciousness while having dinner. A,B) Right internal carotid injection revealed an embolus lodging in the right MCA (arrows in the distal M1 portion, TIMI Grade 0). C,D) Immediate recanalization of the M1 segment was observed after balloon disruption of the embolus. 240,000 units UK were infused locally, but the distally migrated fragment did not dissolve (arrows in figure 5D). The procedure was terminated as all the neurological deficits quickly disappeared.