Guidelines consensus Guidelines for the early diagnosis and treatment of transient ischemic attack in China

Definition and application

Guidance specifications

Essentially, transient ischemic attack (TIA) and cerebral infarction are different stages
of the dynamic process of ischemic brain injury.
It is recommended that in the emergency department, for patients with symptoms lasting ≥ 30 minutes, the green channel assessment
is initiated according to the acute ischemic stroke process.

In hospitals with conditions, diffusion-weighted magnetic resonance (DWI) is used as the main diagnostic technique as much as possible, and if no evidence of acute cerebral infarction is found, the diagnosis is confirmed by imaging to confirm TIA
.
If there is clear evidence of acute cerebral infarction, TIA
is no longer diagnosed regardless of the duration of the attack.

For hospitals without emergency DWI diagnosis conditions, improve other structural imaging examinations as soon as possible, and diagnose cerebral infarction if evidence of acute infarction in the corresponding part of the brain is found within 24 hours, and those who do not find it are diagnosed as clinically confirmed TIA
.

For community-based epidemiological studies, given the impracticality of routine histological criteria diagnosis, and taking into account the comparability and continuity of data from international and previous epidemiological studies, it is recommended to continue to use the traditional 24-hour definition and diagnose a clinically confirmed TIA
.

Early diagnosis and evaluation

Guidance specifications

1.
Within 2~7 days after the onset of TIA, it is a high-risk period of stroke, optimize the allocation of medical resources, establish an emergency medical model based on ABCD2 score (Table 1) stratification and imaging, and start the evaluation and secondary prevention
of TIA as soon as possible.

Table 1 ABCD2 Rating Scale

Note: ABCD2 score 0~3 is judged as a low-risk group; 4~5 is divided into medium risk groups; 6~7 is divided into high-risk groups
.

2.
New-onset TIA is treated as an emergency, and if the patient has one of the following conditions within 72 hours of symptom onset, it is recommended to be hospitalized: (1) ABCD2 score ≥ 3; (2) Patients with an ABCD2 score of 0~2 points, but cannot guarantee that they can complete the system examination in the outpatient clinic within 2 days; (3) ABCD2 score 0~2 points, and other evidence suggests that the symptoms are caused by
ischemia.

3.
Perform a comprehensive examination and evaluation of patients with new-onset TIA (Figure 1).

Fig.
1 Triage process of stroke patients

Because thrombolytic therapy for non-disabling ischemic cerebrovascular disease may be beneficial, the evidence is insufficient, and thrombolytic therapy
can be individualized according to the actual situation of physicians and patients.

(1) General examination: evaluation includes electrocardiogram, complete blood count, coagulation function, blood electrolytes, renal function and rapid blood glucose and lipid measurement
.

(2) Vascular examination: CT angiography (CTA), magnetic resonance angiography (MRA), vascular ultrasound, and whole cerebral angiography (DSA) can find important intracranial and extracranial vascular lesions
.
DSA is the gold standard
for preoperative evaluation of carotid endarterectomy (CEA) and carotid artery stent therapy (CAS).

(3) Collateral circulation compensation and cerebral blood flow reserve assessment: The use of DSA, cerebral perfusion imaging and/or transcranial color Doppler ultrasound (TCD) examination to evaluate collateral circulation compensation and cerebral blood flow reserve is necessary
to identify hemodynamic TIA and guide treatment.

(4) Examination of vulnerable plaques: Vulnerable plaques are an important source of
arterial emboli.
Vascular ultrasound, endovascular ultrasound, high-resolution MRI, and TCD microemboli monitoring are helpful in evaluating vulnerable plaques in
atherosclerosis.

(5) Cardiac evaluation: suspected cardiogenic embolism, or under 45 years of age neck and cerebrovascular examination and hematological screening can not determine the cause, it is recommended to perform transthoracic echocardiography (TTE) and/or transesophageal echocardiography (TEE) examination, which may find multiple emboli sources such as cardiac wall thrombosis, abnormalities of atrial septum (atrioventricular aneurysm, patent foramen ovale, atrial septal defect), mitral valve vegetation and aortic toxosclerosis
.

(6) Do other relevant examinations
according to the medical history.

treat

(1) Thrombolytic therapy in the acute phase

1.
TIA is an important acute disease, early disability rate and high risk of recurrence, in the emergency department, for symptoms lasting ≥ 30 minutes, should be evaluated according to the acute ischemic stroke process
.

2.
So far, there is still a lack of evidence-based medical evidence for TIA thrombolysis, and it is recommended that patients with large arterial stenosis and high NIHSS scores should refer to the principles of vascular recanalization therapy in the acute phase of ischemic stroke for intravenous
thrombolysis or mechanical thrombectomy.

(2) Oral antithrombotic drug treatment

1.
Antithrombotic therapy for non-cardiogenic TIAs

(1) For patients with non-cardiogenic TIA, it is recommended to give oral antiplatelet drugs instead of anticoagulant drugs to prevent stroke recurrence and other cardiovascular events
.

(2) Aspirin (50~325 mg/d) or clopidogrel (75 mg/d) monotherapy can be used as the preferred antiplatelet drug
.
The optimal dose of aspirin antiplatelet therapy is 75~150 mg/d
.
Aspirin (25 mg) + extended-release dipyridamole (200 mg) twice daily, or cilostazol (100 mg) twice daily, can be used as an alternative to aspirin and clopidogrel
.
Latest evidence: The results of a recently published study of ticagrelor and aspirin in acute ischemic stroke and TIA (SOCRATES) suggest that ticagrelor treatment within 24 hours of onset of illness in patients with non-cardiogenic high-risk TIA (ABCD2 score ≥ 4) is no different in safety than aspirin, but not as effective as aspirin
.
Therefore, antiplatelet agents should be selected
on an individual basis based on patient risk factors, cost, tolerability, and other clinical characteristics.

(3) Acute non-cardiogenic TIA with a high risk of stroke recurrence (ABCD2 score ≥ 4) within 24 hours of onset should be given aspirin combined with clopidogrel as soon as possible for 21 days
.
Aspirin or clopidogrel can then be used as first-line drugs for long-term secondary prevention
.
Latest evidence: The newly published results of the study of new-onset TIA and platelet suppression therapy (POINT) for minor ischemic stroke 211 further justify this regimen
.
The study showed that aspirin combined with clopidogrel for 90 days reduced the risk of a combined cardiovascular event at 90 days in patients with noncardiogenic high-risk TIAs, but also increased the incidence of
bleeding events.
Therefore, treatment with non-cardiogenic high-risk TIAs, acute aspirin plus clopidogrel is appropriate
for 21 days.

(4) TIA patients with severe stenosis of the symptomatic intracranial artery (stenosis rate 70%~99%) within 30 days of onset should be given aspirin combined with clopidogrel as soon as possible for 90 days
.
Aspirin or clopidogrel can then be used as first-line drugs for long-term secondary prevention
.

(5) For TIA patients with evidence of atherosclerotic plaque of the aortic arch, antiplatelet and statin therapy is
recommended.
There are no firm conclusions
on the effects of oral anticoagulants compared with aspirin plus clopidogrel.

(6) For patients with non-cardiogenic TIA, routine long-term aspirin combined with clopidogrel antiplatelet therapy
is not recommended.

2.
Antithrombotic therapy for cardioembolic TIA

(1) For TIA patients with atrial fibrillation (including paroxysmal), it is recommended to use an appropriate dose of warfarin oral anticoagulation therapy to prevent recurrent thromboembolic events
.
The target dose of warfarin should be maintained at 2.
0~3.
0
.

(2) New oral anticoagulants can be used as alternative drugs for warfarin, and new oral anticoagulants include dabigatran, rivaroxaban, apixaban and edoxaban, and the choice of which drug should consider individualized factors
.

(3) Patients with TIA with atrial fibrillation who cannot receive oral anticoagulation are recommended to be treated with aspirin monotherapy
.
Aspirin plus clopidogrel antiplatelet therapy
may also be an option.

(4) Patients with TIA with atrial fibrillation should choose the timing of anticoagulation according to the severity of ischemia and the risk of bleeding transformation, and give anticoagulation therapy to prevent stroke recurrence, and for patients with high bleeding risk, the start time
of anticoagulation should be appropriately delayed.

(5) TIA patients should undergo 24-hour Holter examination
as much as possible.
In patients of unknown cause, extended ECG monitoring is recommended to determine whether anticoagulation is indicated
.

(6) For TIA patients with acute myocardial infarction, left ventricular wall thrombosis is found on imaging, and warfarin oral anticoagulation therapy is recommended for at least 3 months (target INR value is 2.
5; range 2.
0~3.
0).

If there is no left ventricular wall thrombosis, but no movement or abnormal movement of the anterior wall is found, oral anticoagulation with warfarin for 3 months should also be considered (target INR value is 2.
5; range 2.
0~3.
0).

(7) For TIA patients with rheumatic mitral valve disease but no atrial fibrillation and other risk factors (such as carotid artery stenosis), oral anticoagulation with warfarin is recommended (target INR value is 2.
5; range 2.
0~3.
0).

(8) For patients with rheumatic mitral valve disease who have been treated with warfarin anticoagulation, after the occurrence of TIA, routine combination of antiplatelet therapy
should not be used.
However, when ischemic stroke or TIA still occurs during adequate warfarin treatment, aspirin antiplatelet aggregation therapy
can be added.

(9) Patients with TIA who are not accompanied by atrial fibrillation with non-rheumatic mitral valve disease or other valvular lesions (local aortic arch calcification, mitral annular calcification, mitral valve prolapse, etc.
) can consider antiplatelet aggregation therapy
.

(10) For TIA patients implanted with prosthetic heart valves, long-term warfarin oral anticoagulation is
recommended.

(11) For patients with a history of TIA who have implanted prosthetic heart valves, if the risk of bleeding is low, aspirin can be added to warfarin anticoagulation
.

(3) Non-drug treatment for symptomatic atherosclerotic transient ischemic attack

1.
Carotid extracranial stenosis

(1) For patients with recent TIA combined with ipsilateral carotid extracranial segment and severe stenosis (50%~99%), if the risk of perioperative death and stroke recurrence is expected to be <6%, CEA or CAS treatment<b10> is recommended.
The choice of CEA or CAS should be individualized
on a patient-by-case basis.

(2) When the degree of carotid extracranial stenosis < 50%, CEA or CAS treatment<b10> is not recommended.

(3) When TIA patients have indications for CEA or CAS treatment, if there is no contraindication to early recanalization, surgery
should be performed within 2 weeks.

2.
Stenosis of the extracranial vertebral artery

In patients with TIA with symptomatic extracranial atherosclerotic stenosis, stenting may be used as an adjunctive technical means
for medical drug treatment when medical therapy is ineffective.

3.
Subclavian artery stenosis and cephalic brachial trunk stenosis

(1) Patients with TIA who have symptoms of posterior circulatory ischemia (subclavian artery theft syndrome) caused by subclavian artery stenosis or occlusion can be treated with stenting or surgery if standard medical treatment is ineffective and there are no contraindications to surgery
.

(2) Patients with TIA caused by common carotid artery or brachiocephalococcal trunk lesions, medical drug treatment is ineffective, and there is no contraindication to surgery, and stenting or surgical treatment can be performed
.

4.
Intracranial artery stenosis

For 70% of patients with TIA with symptomatic intracranial atherosclerotic stenosis≥ endovascular intervention can be selected as an adjunctive technical means for medical drug treatment when standard medical treatment is ineffective, but the selection of patients should be strict and cautious
.