BA Occlusive disease in the NEMC registry

407 patients in the New England Medical Center Posterior Circulation Stroke Registry were divided into 3 groups, including 109 with BA disease. 87 were moderate to severe.
(39) Group 1 had intrinsic and isolated disease usually atherosclerosis with superimposed thrombus.
(36) Group 2 had severe and extensive athero with additional/multiple sites in posterior circulation
(12) Group 3 had emboli to the BA from the heart or vertebral arteries.

Differences: Group 3 (embolic group) were significantly younger (49) v. 66, 60.
All groups had patients with many risk factors. Those without risk factors included 2 traumatic dissections, 1 BAM, 1 hypercoagulable state due to AIDS. Women were more likely to be in Group 2, men in group 1 (women had more widespread athero). Of the cardioembolic patients, 2 took BC pills, 75 % had 0 or 1 risk factors.

Presentation in group 1 was most often hemiparesis, in group 2, vertigo and dizziness, and in group 3, eye movement disorders, alteration of consciousness and tetraparesis.

TIA was much more common, with or without stroke in groups 1 and 2. TIA followed by stroke was more common than TIA only or stroke only (2/3 had TIA, 40 % followed by stroke, 27 % not). Stroke mechanism by far, was most commonly due to hemodynamic compromise with large artery occlusive disease (74%) becomes 87% if embolic are excluded. The rest were mixed (artery to artery embolus, BAM, coagulopathy, unknown). Cardiac mechanism was congenital heart lesions in 4, ASD in 2, PFO in one, AF due to thyrotoxicosis or chronic, mural thrombus.

Prognosis was worst in group C due to major deficit (58%), best in group 2 with 83 % having no or minor disability. Bad prognostic signs were impaired LOC, tetraparesis/tetraplegia. and pupillary abnormalities. BA occlusion was worse than stenosis. Involvement of the distal territory of the BA was highly predictive of disability whereas all patients with proximal stenosis alone had favorable prognosis. Overall mortality at 30 days was low and only one fifth had major disability.

Blogger note: Discussion indicates a benign outcome in many patients with such disease including BA occlusion, and the current registry analyzes factors that affect prognosis. Julien Bogouslavvsky wrote the editorial called "basilar occlusive disease: the descent of the feared foe?" and compares his experiences. He also mentions the embolic "proximal-distal syndrome" characterizes by ataxia and visual field deficits, usually due to occlusion of PICA with emboli northwards.