Possible clinical and radiological predictors of haemorrhagic transformation in acute stroke patients undergoing dual antiplatelet therapy: a clinical study

Background: The predictors of intracranial haemorrhagic transformation (HT) in acute ischaemic stroke (AIS) patients undergoing dual antiplatelet therapy (DAPT) are not well known. Objectives: The aim of this study is to identify the possible clinical and radiological predictors of HT in patients, irrespective of clinical indication for this treatment. Design: This study is a monocentric cohort retrospective study. Methods: We enrolled consecutive AIS patients, from our prospective register, admitted to Stroke Unit between June 2021 and June 2023 undergoing DAPT with Acetylsalicylic Acid and Clopidogrel within 72 h from symptoms onset. According to current guidelines, DAPT indication was for patients with a minor stroke, symptomatic intracranial artery stenosis and carotid angioplasty stenting. We collected clinical, demographical and radiological data. We used ABC/2 method to measure stroke volume in magnetic resonance imaging (MRI)/Diffusion-weighted imaging (DWI) sequences performed within 48 h. The primary outcome was the presence of HT at non-contrast brain computed tomography, performed 7 days after commencing DAPT. Results: One hundred ninety-four patients were included. Twenty-eight (14.4%) presented HT. Higher NIH Stroke Scale (NIHSS) and MRI/DWI lesion volume related to increased risk of HT (p < 0.001). Reperfusion therapy and mechanical thrombectomy (MT), stent placement and a loading dose (LD) of dual antiplatelet or Clopidogrel were associated with a higher occurrence of HT (p < 0.05). Furthermore, we individuated an NIHSS cut-off value >4 (area under the curve (AUC) 0.80, sensitivity 0.82, specificity 0.65) and a volume cut-off value >8.2 ml (AUC 0.82, sensitivity 0.79, specificity 0.80) associated with an increased risk of HT (respectively, adjusted odds ratio (adj. OR) 6.5, confidence interval (CI) 1.3-32.7, p = 0.024 and adj. OR 11.0, CI 3.1-39.2, p < 0.001). Conclusion: In clinical practice, MT treatment, antiplatelet LD administration, stent placement and clinical severity may relate to a higher risk of HT in patients with AIS and DAPT in the acute phase. In particular, we found that lesion volume cut-off could help to identify patients at greater risk of HT, regardless of the indication for DAPT.