We administered hyperbaric oxygen or air in a double-blind prospective protocol to 39 patients with ischemic cerebral infarction. We interrupted the study when we noticed what appeared to be a trend favoring the air-treated patients, whose neurological deficits were less severe (mean±SEM score on graded neurological examination: air, 25.6±4.9; oxygen, 34.5±7.5) and whose infarcts were smaller (air, 29.0±12.2 cm 3 ; oxygen, 49.2 ±11.7 cm 3 ) at 4 months. The trend, we decided, was probably an artifact of the randomization process. Nevertheless, we chose not to resume the trial because the treatment was difficult to administer by schedule (for various reasons the treatment protocol was broken in 15 of the 39 patients), was poorly tolerated (eight of the 39 patients refused to continue treatments), and did not produce dramatic improvement (Stroke 1991^2:1137-1142)

We report the detailed clinical and pathologic account of a patient with an ischemic infarction restricted to both medullary pyramids. Although prevailing neurophysiologic teachings would predict a flaccid paralysis, the patient's pure motor quadriplegia was eventually associated with spasticity.

Atrial fibrillation, even in the absence of rheumatic valvular disease, predisposes patients to embolic complications, but the role of antithrombotic therapy in the prevention of such complications has not been fully clarified. We therefore performed a randomized, placebo-controlled trial to evaluate warfarin and aspirin individually as prophylaxis against ischemic stroke and systemic embolism (the primary events) in such patients. Patients eligible to receive warfarin (group 1) were assigned to warfarin (open label), aspirin (325 mg per day), or placebo (aspirin and placebo were given in a doubleblind fashion). Those who were not eligible for warfarin (group 2) received either aspirin or placebo in a double-blind fashion. The placebo arm of group 1 was recently terminated, when evidence emerged that each active agent was superior to placebo. In this paper we report preliminary data on active therapy (with either warfarin or aspirin) as compared with placebo in group 1, and on aspirin as compared with placebo in groups 1 and 2 combined. By November 1989, 1244 patients had been followed for a mean of 1.13 years. The event rates were 1.6 percent per year in the 393 patients who made up the two active treatment arms (warfarin and aspirin) of group 1, and 8.3 percent per year in the 195 patients who made up the placebo arm (P less than 0.00005) (risk reduction, 81 percent; 95 percent confidence interval, 56 to 91). In all 517 patients given aspirin, the rate of primary events (3.2 percent per year) was lower than that in the 528 patients given placebo (6.3 percent per year; P = 0.014) (risk reduction, 49 percent; 95 percent confidence interval, 15 to 69). However, we were unable to show a benefit of aspirin in patients over 75 years of age. These preliminary data indicate that antithrombotic therapy with warfarin or aspirin is effective in the short term in reducing the risk of stroke and systemic embolism in patients with atrial fibrillation due to causes other than rheumatic valvular disease. The relative benefits of aspirin and warfarin remain unclear, and the trial is continuing in order to address this issue.

NVAF was associated with a fivefold increase in the risk of stroke. Up to 35% of all patients with NVAF eventually suffer cerebral infarction, 57 -9 and the yearly risk of stroke in these patients approaches It is believed that many, and perhaps most, strokes that occur in patients with NVAF are due to cardiogenic embolism from thrombus material originating in the left atrium, especially the appendage, 10 -12 so prevention of initial thrombus formation may be beneficial. Using this rationale, some physicians prescribe anticoagulants for patients with NVAF. Other physicians, fearing the complications of anticoagulation, recommend nothing or, as in recent years, empirically use aspirin as a safer antithrombotic agent. Well-designed clinical studies addressing the benefits and risks of these approaches are long overdue.From the Stroke Prevention in Atrial Fibrillation Study.