The following cases and commentary, which focus on stroke care, are excerpted from ACP's Medical Knowledge Self-Assessment Program (MKSAP 16). Part A of MKSAP 16 was released on July 31.
Case 1: Elderly woman with an ischemic stroke
An 86-year-old woman is evaluated in the emergency department 60 minutes after onset of difficulty speaking and right arm weakness. The patient has a 5-year history of atrial fibrillation for which she takes warfarin. She has no history of previous stroke or gastrointestinal or genitourinary bleeding.
On physical examination, blood pressure is 170/100 mm Hg and pulse rate is 86/min and irregular. Neurologic examination shows global aphasia, right hemiparesis, left gaze preference, and a right visual field cut.
Laboratory studies show an INR of 1.1, a platelet count of 180,000/µL (180 × 109/L), and a fasting plasma glucose level of 120 mg/dL (6.7 mmol/L).
A CT scan of the head shows no acute infarct or hemorrhage.
Which of the following is the most appropriate next step in treatment?
A. High-dose aspirin
B. Intravenous heparin
C. Intravenous recombinant tissue plasminogen activator
Case 2: Symptoms for an hour
A 75-year-old woman is evaluated for a 60-minute episode of right arm weakness and dysarthria. The symptoms have not recurred. She has hypertension and type 2 diabetes mellitus. Medications are aspirin, metoprolol, enalapril, and metformin.
On physical examination, blood pressure is 156/94 mm Hg, pulse rate is 62/min and regular, and respiration rate is 16/min. No carotid bruits are noted. Neurologic examination findings are normal.
Results of laboratory studies obtained 3 weeks ago show a hemoglobin A1c value of 7.1% and a serum LDL cholesterol level of 68 mg/dL (1.76 mmol/L).
Which of the following is the most appropriate next step in management?
A. Addition of clopidogrel
B. Immediate hospital admission
C. Outpatient MRI of the brain
D. 24-Hour electrocardiographic monitoring
Case 3: Next steps in a younger patient
A 46-year-old woman is admitted to the stroke unit for new-onset left hemiparesis and left-sided neglect.
On physical examination, temperature is normal, blood pressure is 140/78 mm Hg, pulse rate is 68/min, and respiration rate is 12/min. Cardiopulmonary examination is normal. Other notable findings are a right carotid bruit, right Horner syndrome, left visual and tactile extinction, left facial weakness, dysarthria, and left arm and leg weakness (strength, approximately 3/5). On bedside dysphagia screening, she is unable to safely swallow water and has a mild cough.
Results of laboratory studies show an INR of 1.1, a serum creatinine level of 0.9 mg/dL (79.6 µmol/L), and an LDL cholesterol level of 68 mg/dL (1.76 mmol/L).
A CT scan of the head shows a right middle cerebral artery infarction. An MRI of the neck shows an intraluminal thrombus consistent with internal carotid artery dissection.
Low-molecular-weight heparin is started.
Which of the following is the most appropriate next step in management?
B. Early rehabilitation
D. Stenting of the internal carotid artery
Case 4: Hypertension in a stroke patient
A 78-year-old woman is evaluated in the emergency department 12 hours after onset of left-sided weakness and slurred speech. She reports being unable to swallow water at home. She has a history of hypertension and type 2 diabetes mellitus, both of which she tries to control with lifestyle modifications.
On physical examination, blood pressure is 190/90 mm Hg, pulse rate is 68/min and regular, and respiration rate is 16/min. Cardiac examination reveals no carotid bruits. Neurologic examination reveals facial weakness on the left side, severe dysarthria, left-sided hemiplegia, left-sided sensory loss, and normal mental status.
Results of laboratory studies show a serum creatinine level of 1.1 mg/dL (97.2 µmol/L) and no serum troponins; urinalysis findings are normal.
A CT scan of the head shows a faint hypodensity in the right posterior limb of the internal capsule. An electrocardiogram shows normal sinus rhythm with no ischemic changes. A chest radiograph is normal.
Which of the following is the most appropriate treatment of this patient's elevated blood pressure?
A. Intravenous hydralazine
B. Oral candesartan
C. Oral labetalol
D. Oral nitroglycerin
E. No treatment is required
Case 5: Weakness, slurred speech and history of stroke
A 46-year-old man is evaluated in the emergency department 4 hours after onset of right-sided weakness and slurred speech. He has a history of hypertension, type 2 diabetes mellitus, and an ischemic stroke 2 years ago with excellent recovery. He stopped his medications 6 months ago.
On physical examination, the patient is awake and interactive. Blood pressure is 170/100 mm Hg, pulse rate is 102/min and regular, and respiration rate is 16/min. No carotid bruits are heard. On neurologic examination, he has slurred speech and makes occasional paraphasic errors. A right visual field cut and right arm and leg drift are noted. The patient has normal results of a bedside dysphagia evaluation.
Laboratory studies show activated partial thromboplastin time 36 s, INR 0.9, platelet count 410,000/µL (410 × 109/L), creatinine 2.1 mg/dL (186 µmol/L), LDL cholesterol 190 mg/dL (4.92 mmol/L), troponins normal.
A CT scan of the head without contrast shows a loss of the left insular ribbon. A magnetic resonance angiogram confirms severe extracranial carotid artery stenosis. An electrocardiogram is normal.
Which of the following is the most appropriate next step in treatment?
B. Intravenous recombinant tissue plasminogen activator
Case 6: Admission decision in the ED
A 73-year-old woman is evaluated in the emergency department for left-sided weakness that began 36 hours ago. She reports no changes in her vision or speech. The patient has a history of hypertension and coronary artery disease. Medications are aspirin, losartan, metoprolol, and atorvastatin.
On physical examination, blood pressure is 160/78 mm Hg, pulse rate is 78/min and regular, and respiration rate is 16/min. Other findings from the general medical examination are normal. Neurologic examination shows severe paralysis of the left face, arm, and leg.
Results of laboratory studies are normal.
A CT scan of the head shows an infarct in the right posterior limb of the internal capsule. An electrocardiogram is normal.
Which of the following is the most appropriate immediate next step in management?
A. Admit to a stroke unit
B. Admit to rehabilitation
C. Admit to the general medical ward
D. Admit to the medical intensive care unit
Answers and commentary
Correct answer: C. Intravenous recombinant tissue plasminogen activator.
This patient should receive intravenous recombinant tissue plasminogen activator (rtPA). She is evaluated only 60 minutes after onset of acute ischemic stroke, which is well within the window for administration of the drug, and has a measurable deficit on neurologic examination. She does not meet any of the exclusion criteria that would prevent administration: her INR and platelet count are within the guideline limits, her blood pressure is less than 185/110 mm Hg, and imaging shows no hemorrhage. The National Institute of Neurological Diseases and Stroke (NINDS) rtPA trial showed that patients who received intravenous rtPA within 3 hours of stroke onset had a greater likelihood of clinical improvement at 3 months than did those who received placebo. The trial had no upper limit of neurologic deficit or age.
High-dose (325-mg) aspirin is appropriate for patients who are not eligible for intravenous rtPA. However, in those who have received intravenous rtPA, antiplatelet agents must be withheld for at least 24 hours.
Intravenous heparin does not reduce the risk of recurrent embolic stroke or mortality in patients with stroke who have atrial fibrillation and thus is the wrong therapeutic choice for this patient.
Administering labetalol to lower this patient's blood pressure is also inappropriate. For an uncomplicated ischemic stroke in patients without concurrent acute coronary artery disease or heart failure, antihypertensive medications should be withheld unless the systolic blood pressure is greater than 220 mm Hg or the diastolic blood pressure is greater than 120 mm Hg. If the patient is eligible for thrombolysis, blood pressure must be lowered and stabilized below 185 mm Hg systolic and 110 mm Hg diastolic before thrombolytic therapy is started. Because this patient's blood pressure (170/100 mm Hg) is less than those limits, an antihypertensive medication, such as labetalol, is not required. After thrombolysis, the target blood pressure is less than 180 mm Hg systolic and 105 mm Hg diastolic for at least 24 hours.
- Intravenous recombinant tissue plasminogen activator should be administered to a patient with ischemic stroke if it can be given within 3 hours of stroke onset and the patient meets the guideline criteria.
Correct answer: B. Immediate hospital admission.
This patient most likely has had a transient ischemic attack (TIA) and should be admitted to the hospital immediately. Her ABCD2 score is 7 (one point for an Age of 60 years or greater, one point for a Blood pressure of 140/90 mm Hg or greater, two points for the Clinical symptom of hemiparesis, two points for Duration of 60 minutes or greater, and one point for the presence of Diabetes mellitus), which indicates a 2-day stroke risk of 8.1%. The American Heart Association guidelines recommend hospital admission for all patients with probable TIAs whose ABCD2 scores are 3 or greater. A noninvasive stroke evaluation can be completed more quickly in the hospital, with a particular focus on excluding cerebral infarction as a cause of symptoms and diagnosing the presence of intracardiac thrombi and extracranial internal carotid artery stenosis.
No evidence supports the combination of aspirin and clopidogrel for stroke prevention, and the use of the two agents in TIA remains investigational. The combination of aspirin and clopidogrel was associated with a reduction in the risk of recurrent stroke or myocardial infarction in a major study, but the benefit was offset by a significant increase in the risk of intracerebral hemorrhage.
MRI may be ultimately indicated in this patient to rule out ischemic stroke and, in combination with magnetic resonance angiography, to evaluate the cause of the patient's transient ischemic attack. However, MRI is often not readily available and, in any case, would not influence the decision to admit the patient.
Although 24-hour electrocardiographic monitoring may be indicated for the evaluation of paroxysmal atrial fibrillation, the immediate next step is to admit this patient to the hospital for observation and to complete a stroke evaluation and monitor for recurrence.
- All patients with probable transient ischemic attacks whose ABCD2 scores (based on Age, Blood pressure, Clinical symptoms, Duration, and presence of Diabetes mellitus) are 3 or greater should be admitted to the hospital for evaluation.
Correct answer: B. Early rehabilitation.
Early rehabilitation should be initiated in this patient as soon as she is medically stable. She has had an acute ischemic stroke with an identified cause that resulted in significant motor dysfunction. Without early mobility, she is at high risk for deep venous thrombosis, atelectasis, contractures, and skin breakdown. Patients with motor or cognitive dysfunction from stroke should be further evaluated in an expedited manner by physical and occupational therapists and by speech and swallow therapists for the ability to swallow liquids safely. Early rehabilitation can have significant beneficial effects on stroke recovery. Other steps to improve stroke recovery include screening for and treating poststroke depression and minimizing the occurrence of poststroke medical complications, such as pneumonia and urinary tract infections.
Amoxicillin-clavulanate is inappropriate because the patient has no clinical evidence of pneumonia. She is afebrile and has normal results on pulmonary examination, despite being at risk for aspiration. Prophylactic antibiotics in patients with stroke who are at risk for aspiration have not been shown to be effective in reducing the incidence of pneumonia.
The central nervous system stimulant modafinil is unlikely to help this patient. In general, pharmacologic agents, including amphetamines, have yet to be shown to improve stroke recovery.
Stenting of the internal carotid artery is inappropriate in this patient who has not experienced recurrent symptoms and has no evidence of continuing ischemia. Stenting in the setting of carotid artery dissection, in fact, remains a risky and unproved procedure.
- Aggressive rehabilitation as soon as patients are medically stable can have significant beneficial effects on stroke recovery.
Correct answer: E. No treatment is required.
This patient does not require treatment of her elevated blood pressure (190/90 mm Hg) at this time. Because her initial evaluation occurred 12 hours after her acute ischemic stroke, she is not a candidate for intravenous recombinant tissue plasminogen activator (rtPA). The American Heart Association guidelines support allowing blood pressures of up to 220/120 mm Hg in patients with ischemic stroke who are ineligible for rtPA treatment, unless evidence of end-organ damage (active ischemic coronary disease, heart failure, aortic dissection, hypertensive encephalopathy, acute kidney failure, or preeclampsia/eclampsia) exists. Treatment with antihypertensive agents in the acute setting may lead to neurologic worsening due to a decline in cerebral perfusion in the area of the tissue at risk (penumbra). In the recently completed Scandinavian Candesartan Acute Stroke Trial (SCAST), treatment with candesartan was associated with a trend toward worse outcomes, primarily because of worsening neurologic status. The blood pressure target of less than 220/120 mm Hg is maintained until hospital discharge to home or a rehabilitation facility, at which time patients can begin or resume taking antihypertensive medication.
Intravenous hydralazine is inappropriate because the patient does not require immediate treatment for hypertension. Candesartan, labetalol, and nitroglycerin are inappropriate for the same reason. Additionally, because this patient is at high risk for aspiration, oral medications should not be administered until a formal dysphagia screen is performed.
- Patients with ischemic stroke who are ineligible to receive recombinant tissue plasminogen activator and have no evidence of end-organ damage should not be treated for elevated blood pressure of up to 220/120 mm Hg.
Correct answer: A. Atorvastatin.
This patient should now receive atorvastatin. He had an ischemic stroke in the distribution of the internal carotid artery. Given his severe stenosis and other risk factors, the stroke was most likely atherosclerotic. In all patients with stroke and an LDL cholesterol level greater than 100 mg/dL (2.59 mmol/L), clinical trial data support the use of a high-dose statin to prevent recurrent ischemic stroke and myocardial infarction.
Although this patient is still within the expanded 4.5-hour treatment window for a recombinant tissue plasminogen activator (rtPA), he is not a candidate for treatment because of his history of ischemic stroke and diabetes mellitus.
In patients with stroke who are not candidates for intravenous rtPA, a blood pressure of less than 220/120 mm Hg is recommended in the acute setting unless evidence of end-organ damage (such as myocardial infarction or kidney injury) exists. Therefore, using an antihypertensive agent, such as nicardipine, in this patient is inappropriate at this time.
Warfarin also is inappropriate for this patient, who does not have a history of atrial fibrillation. In large artery atherosclerosis, warfarin was not shown to be superior to antiplatelet agents in the Warfarin-Aspirin Recurrent Stroke Study (WARSS).
- In patients with stroke and a serum LDL cholesterol level greater than 100 mg/dL (2.59 mmol/L), clinical trial data support the use of a statin to prevent recurrent ischemic stroke and myocardial infarction.
Correct answer: A. Admit to a stroke unit.
This patient should be admitted to the nearest stroke unit. Several studies have shown that admission to an organized inpatient stroke unit compared with a general medical ward is associated with a reduction in mortality at 1 year and that benefits persist up to 10 years after stroke onset. Stroke units are likely to be beneficial because of the multidisciplinary nature of care, with an emphasis on specialized nursing and early rehabilitation.
Admission to rehabilitation may ultimately be indicated, but at this time hemodynamic stability needs to be established, and evaluation for stroke cause, including cardiac testing and vascular imaging, is required.
No clear indication exists that this patient requires admission to the intensive care unit, particularly given that her blood pressure should not be lowered acutely.
- Admission of patients with stroke to an inpatient stroke unit compared with a general medical ward is associated with a reduction in mortality at 1 year, and that benefit persists for up to 10 years after stroke onset.