The capillary index score: rethinking the acute ischemic stroke treatment algorithm. Results from the Borgess Medical Center Acute Ischemic Stroke Registry

Background Despite increased recanalization rates in the treatment of acute ischemic stroke, the percentage of patients with a good clinical outcome of all those treated has not risen above 50%. This 50% barrier may be broken by improving the criteria for treatment selection. This study investigated the addition of the capillary index score (CIS), a new index for assessing remaining viable tissue in the ischemic area, to the existing criteria. Methods The Borgess Medical Center Ischemic Stroke Registry is a non-randomized single-center single-operator registry of consecutive subjects admitted for intra-arterial treatment of acute ischemic stroke. The CIS was calculated from a pre-intervention catheter cerebral angiogram in subjects with internal carotid artery (ICA) or middle cerebral artery (MCA) (M1) occlusion. Thrombolysis In Myocardial Infarction (TIMI) 2 or 3 was considered successful recanalization. A modified Rankin Scale (mRS) of 0-2 at 3 months was considered a good outcome. Results ICA or MCA (M1) occlusion was found in 46 of 58 consecutive patients treated by the same operator. Recanalization was successful in 72% of patients and 27% had a good outcome. CIS was available for 26 patients; 42% were favorable (2 or 3) and 58% were poor (0 or 1). A good outcome was found only in the favorable CIS group (p=0.0148). Successful recanalization (p=0.0029) and time from ictus to revascularization (p=0.0039) predicted a good outcome. Of patients with favorable CIS and TIMI 3, 83% had a good outcome. Conclusions Favorable CIS and recanalization were strong predictors of a good outcome. By using this new index as an adjunct to other criteria, the CIS may improve patient selection and help break the 50% barrier.