Interventions to treat chronic hypertension have been demonstrated to reduce the rate of strokes by approximately 30% to 40% over four to five years.15-16 An optimal agent has not been determined, but therapy with angiotensin converting enzyme inhibitor (ACE-I) or angiotensin II receptor blocker (ARB), possibly in combination with a diuretic, have been effective. Close follow-up for titration to goal in the outpatient setting should be arranged. Diabetics should have optimization of glycemic control, and lifestyle counseling should occur regarding recognized risk factors for stroke such as smoking, inactivity, and alcohol abuse.
While antithrombotic therapy is the mainstay of what we think of in secondary prevention of stroke, treatment of these other modifiable risk factors have been shown to affect mortality and second strokes of a similar magnitude and should not be neglected.
How to Treat This Case
The patient described should undergo an MRI with diffusion (to define the area of ischemia) and targeted evaluation for etiology with cardiac monitoring, echocardiogram, and carotid ultrasound.
Assuming atrial fibrillation or intracardiac thrombus is ruled out, this likely represents atherosclerotic disease. MRI will help distinguish between large-vessel atherosclerotic etiology and lacunar infarct. If carotid stenosis of greater than 70% is found in the setting of large vessel atherosclerotic stroke, then she should be referred for carotid endarterectomy. At 50% to 69% stenosis, carotid endarterectomy would still be a consideration. Antithrombotic agent of choice for non-cardioembolic CVA is an anti-platelet agent. With a stroke occurring on a reasonable dose of aspirin, I would not recommend increasing the dose as there is little evidence that 325 mg is more effective than 81mg. The most appropriate step would be to change to an alternate anti-platelet agent such as combination dipyridamole/aspirin or clopidogrel.
In the absence of a direct comparison trial, either choice is acceptable. The evidence supporting dipyridamole/aspirin is stronger for secondary stroke prevention. Atorvastatin 80 mg daily is an evidence-based therapy after acute stroke and can be started immediately. Her hypertension should be managed permissively for the first few days after the acute event, but then an ACE-I or ARB—possibly in combination with a diuretic—would be appropriate. This patient’s goal blood pressure as a diabetic would be at least less than 130/80 mm/Hg.
Finally we would be remiss if we did not stress the importance of smoking cessation, exercise, and weight loss. TH
Dr. Cumbler is an assistant professor in the Section of Hospital Medicine at the University of Colorado, where he is a member of the Acute Stroke Service and serves on the Stroke Council.
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