The haematoma expansion paradoxes. A study of haematoma expansion in acute primary intracerebral haemorrhage

Introduction: intracerebral haemorrhage (ICH) accounts for approximately 10-15% of all new strokes that occur each year, but results in disproportionately high morbidity and mortality. Outcome has not improved significantly in recent decades due to the lack of clear beneficial medical or surgical therapies. One of the four factors thought to be responsible for the praecox clinical and radiological deterioration of ICH patients is haematoma expansion (HE). Aims of our study were to analyze the haematoma expansion phenomenon, any risk factors and its influence on outcome, and to evaluate ICH patient characteristics, investigating elements that could contribute to determining ICH outcome. Methods: we conducted an observational longitudinal study on retrospectively collected data on 206 consecutive patients with primary or anticoagulant-associated ICH admitted to the Stroke Units of the Neurology Units of Treviso Hospital and St. Anthony's Hospital of Padova, from January 2011 to December 2015. Patients with a secondary cause of ICH were excluded. We recorded baseline history, radiological, laboratory and clinical admission data, and follow-up information. Results: our ICH population was characterized by elderly Caucasian patients with a slight prevalence of males, small haematoma volumes and mild-moderate clinical severity. While male patients seemed to have a higher incidence of ICH, at a younger age, with a different vascular risk-factor profile and a higher risk of haematoma expansion, outcome was not poorer than in female patients. Of our population, 28.6% presented significant HE and the risk factors for HE proved to be male sex and higher NIHSS score. At follow up, mortality was 24.7% at three months and 28.4% at one year; based on the mRS, the average patient was dependent at three months. At follow up, there was a slightly higher percentage of ICH relapses than of ischemic strokes. Age, haemorrhage characteristics, as baseline volume and ventricular invasion, haematoma expansion and clinical severity are the strongest predictors of outcome. Conclusions and Discussion: the analysis has confirmed the complexity of the haematoma expansion phenomenon, which still remains partially unknown. Our findings have yielded several paradoxes and we wonder whether haematoma expansion can be truly considered a prognostic factor or represents one step in the natural history of every ICH. Considering the natural history of ICH patients, none of the identified prognostic factors is modifiable at the time of medical evaluation. ICH pathology and the haematoma expansion phenomenon are still not sufficiently understood and more studies are warranted to positively influence the prognosis of these patients.