Introduction:
The results of early outcome in thrombolysed stroke patients are connected with the long-term effect measured as disability and death rate. There are different definitions of the early improvement in such patients.

Aim of the research:
To establish potential prognostic factors adversely influencing the early outcome of stroke patients treated with alteplase.

Material and methods:
The analysis of 245 consecutive ischaemic stroke patients treated intravenously with recombinant tissue plasminogen activator (rt-PA) was conducted. The outcome was analysed 24 h after rt-PA treatment depending on the NIHSS score. Group I consisted of 105 patients with the improvement in NIHSS ≥ 2 points 24 h after intravenous rt-PA administration, and group II comprised of the rest of the patients (n = 140).

Results:
The independent factors adversely affecting the early outcome were: hypertension, old ischaemic lesions in initial brain computed tomography (CT), longer therapeutic window, higher baseline NIHSS (respectively: OR = 0.34, p < 0.05; OR = 0.55, p < 0.01; OR = 0.99, p < 0.01; OR = 0.91, p < 0.01).

Conclusions:
There are factors affecting the grade of early neurological improvement assessed 24 h after rt-PA therapy that may help to improve the efficacy of the acute phase treatment and secondary prevention of stroke patients. More attention should be paid to patients with hypertension, those with greater initial neurological deficit, longer onset-to-treatment time, and old ischaemic changes in initial brain CT.