Long-term outcome in posterior cerebral artery stroke.

Introduction:   Previous studies on posterior cerebral artery (PCA) strokes focused mainly on topography and underlying pathophysiology. However, there are no data on long-term prognosis and its association with the localization of the infarct.

Methods:   All consecutive PCA strokes registered in the Athens Stroke Outcome Project between 01/1998 and 12/2009 were included in the analysis. The New England Posterior Circulation Registry criteria were applied to classify them in relation to topography: (i) pure PCA infarcts, including pure cortical-only and combined cortical/deep PCA infarcts (groups A and B respectively), and (ii) PCA-plus strokes, including cortical-only and combined cortical/deep PCA strokes with ≥1 concomitant infarcts outside PCA territory (groups C and D respectively). Patients were prospectively followed up to 10 years after stroke.

Results:   Amongst 185 (8.1%) PCA patients that were followed up for 49.6±26.7months, 98 (53%), 24 (13%), 36 (19.5%), and 27 (14.6%) were classified in group A, B, C, and D, respectively. Infections and brain edema with mass effect were more frequently encountered in PCA-plus strokes compared to pure PCA (P<0.05 and <0.01 respectively). At 6 months, 56% of cortical-only PCA patients had no or minor disability, compared to 37%, 36%, and 26% in the other groups (P=0.015). The 10-year probability of death was 55.1% (95%CI: 42.2-68.0) for pure PCA compared to 72.5% (95%CI: 58.8-86.2) for PCA-plus (log-rank 14.2, P=0.001). Long-term mortality was associated with initial neurologic severity and underlying stroke mechanism.

Conclusions:   Patients with pure PCA stroke have significantly lower risk of disability and long-term mortality compared to PCA strokes with coincident infarction outside the PCA territory.