Table 3.

Clinical characteristics of patients who failed antithrombotic therapy

GroupLocation of lesion (artery)Percent stenosisAntithrombotic therapy at time of initial TIA/strokeNew therapy (after initial failure)Outcome events during follow-upTime to recurrent TIA/stroke or death or length of follow-up if no endpoint occurred (days)
* Diagnosis by MR angiography or MR angiography and transcranial Doppler sonography.
† Diagnosis by transcranial Doppler sonography: mean velocity 100 cm/s.
‡ Patient received warfarin (INR = 2.0–3.0) as chronic antithrombotic therapy.
N/A = not applicable (patients who underwent immediate angioplasty after failure of antithrombotic therapy not included in the follow-up analysis); MCA = middle cerebral artery; WASID = Warfarin Versus Aspirin for Symptomatic Intracranial Disease.
A1Carotid siphon80–90WarfarinHeparinStroke5
Basilar (proximal)95AspirinWarfarinNo endpoint1553
Basilar (middle)80AspirinWarfarinTIA9
Basilar (unspecified)High grade*AspirinWarfarinStroke36
High gradeAspirinWarfarinStroke10
Vertebral (distal)High grade*AspirinWarfarinTIA49
High grade*AspirinTiclopidineNo endpoint30
Vertebral (unspecified)High grade*AspirinWarfarinNo endpoint1272
≥90AspirinWarfarinNo endpoint (angioplasty after 32 d)32
High grade*WarfarinHeparinNo endpoint4
50WarfarinHeparinNo endpoint2062
70HeparinImmediate angioplastyN/A
Carotid siphon≥85AspirinWarfarinNo endpoint (angioplasty after 74 d)74
Basilar (proximal)90AspirinTiclopidineStroke17
≥90WarfarinHeparinNo endpoint1182
Basilar (middle)73AspirinWarfarinTIA20
99HeparinImmediate angioplastyN/A
Basilar (unspecified)High grade*AspirinWarfarinTIA29
Vertebral (distal)80AspirinWASID study drugNo endpoint81
≥80WarfarinImmediate angioplastyN/A
60WarfarinWarfarin and aspirinFatal stroke779
70WarfarinHeparinNo endpoint (angioplasty after 6 d)6
≥95HeparinImmediate angioplastyN/A