OVERVIEW
各种原因所致急性心排血量减少，引起脑供血不足后出现的临床综合征
临床表现为头昏、头痛，一过性黑朦、晕厥、昏倒甚至抽搐、呼之不应
可有冠心病、心律失常、心力衰竭、脑卒中、药物等原因
治疗包括急救，原发病治疗和手术治疗
Definition.
A-s syndrome, or Adams-Stoke syndrome syndrome, also known as cardiogenic ischemia syndrome, is one of the serious life-threatening cardiac emergencies.
A-s syndrome is a clinical syndrome in which cerebral ischemic attack occurs due to a change in the rhythm of the heart, which drastically reduces cardiac output in a short period of time [1-2].
Patients may present with loss of consciousness, syncope, and convulsions, making it one of the most common and dangerous critical cardiovascular emergencies in clinical practice.
Morbidity
There are no accurate statistics on the incidence of A.S. syndrome.
Causes
Causes
Cardiovascular disease
冠心病
Acute anterior myocardial infarction may be complicated by malignant tachyarrhythmias such as pulseless ventricular tachycardia or ventricular fibrillation, resulting in a dramatic decrease in cardiac ejection volume, leading to an attack of A.S. syndrome.
Acute inferior wall myocardial infarction is prone to high degree of atrioventricular block, which can lead to insufficient cardiac output when the heart rate is severely slowed down, resulting in poor cerebral perfusion and an attack of A.S. syndrome.
When the acute myocardial infarction is large, it is easy to lead to acute heart failure, a sharp drop in cardiac output, insufficient cerebral blood supply, and an attack of A. S. syndrome.
Chronic ischemic cardiomyopathy patients myocardium long-term chronic ischemia, myocardial fibrosis, cardiac structural changes, cardiac conduction function abnormalities, can appear all kinds of arrhythmia.
Commonly, such as atrial fibrillation with very fast ventricular rate, ventricular fibrillation, sick sinus node syndrome, third-degree atrioventricular block, etc., can lead to an attack of A. S. syndrome.
心律失常
In addition to arrhythmias due to various primary diseases, there are also idiopathic arrhythmias that can lead to an attack of A. S. syndrome, usually associated with genetic factors, such as long QT interval syndrome, catecholamine-sensitive ventricular tachycardia, and early repolarization syndrome.
心肌病和高血压性心脏病（高心病）
Various types of cardiomyopathies and hypercardiosis may have cardiac ejection channel obstruction, poor myocardial contractility, poor ventricular diastolic function, and myocardial fibrosis, resulting in cardiac ejection failure or the development of malignant arrhythmias such as ventricular fibrillation, and episodes of A. S. syndrome.
心力衰竭
Patients with severe cardiac pump failure may develop pulseless ventricular tachycardia, ventricular fibrillation, cardiac arrest, conduction block, and other conditions leading to an attack of A. S. syndrome.
先天性心脏病
Congenital heart diseases such as tetralogy of Fallot and ventricular septal defects can lead to shunting of blood within the heart, heavy cardiac load, ineffective ejection, and episodes of malignant arrhythmias such as ventricular fibrillation, leading to insufficient blood supply to the brain and episodes of A.S. syndrome.
风湿性心脏病
Rheumatic heart disease patients with heart valves mostly have stenosis or closure insufficiency, the disease gradually progresses, patients can develop heart failure, ventricular fibrillation, resulting in an attack of A. S. Syndrome.
病毒性心肌炎
Outbreaks of viral myocarditis can present with severe myocardial damage and poor blood removal from the heart, which does not ensure blood supply to the brain, and may also lead to dangerous arrhythmias such as third-degree atrioventricular block, or even cardiac arrest and an attack of A. S. Syndrome.
Intracranial diseases
Spontaneous cerebral hemorrhage, acute cerebral infarction, craniocerebral trauma, etc. lead to compression of the brain stem, and the patient may suffer from ventricular fibrillation and cardiac arrest, resulting in an attack of A. S. Syndrome.
Others
Electrolyte disorders (e.g., hyperkalemia, hypokalemia), toxic effects of drugs (e.g., amiodarone, digoxin), pacemaker malfunction, dislodgment of pacing electrodes, and food poisoning (tetrodotoxin) can lead to dangerous arrhythmias and episodes of A. S. syndrome.
Pathogenesis
All of the above diseases may cause the following changes leading to an attack of A. S. syndrome.
Severe slow arrhythmias, such as cardiac arrest and complete atrioventricular block, result in a low or stalled heart rate and a significant reduction in cardiac ejection, leading to inadequate blood supply to the brain.
Tachyarrhythmias, such as tip-twisting ventricular tachycardia and ventricular fibrillation, result in a short diastole, in which blood fails to fill the ventricles, and ineffective contraction of the heart leads to a decrease in blood ejection, resulting in insufficient blood supply to the brain.
Symptoms
Main Symptoms
The most prominent manifestation of A. S. Syndrome is sudden syncope, which may be only vertigo and unconsciousness in mild cases, or complete loss of consciousness in severe cases.
Patients appear pale or blue, pupils dilated, pulse disappears, heartbeat is fast, slow or suspended, often accompanied by convulsions and incontinence.
Cardiac arrest for 2 to 3 seconds may be characterized by dizziness, 4 to 5 seconds by pallor and confusion, 5 to 10 seconds by syncope, and more than 15 seconds by convulsions and cyanosis [3-4].
Complications
Inadequate cerebral blood supply
Acute cerebral insufficiency of blood supply due to a sharp decrease in cardiogenic blood supply during an attack of A. S. syndrome is manifested by symptoms such as vertigo, blackouts, and convulsions.
Traumatic brain injury, fracture
Syndrome may lead to fainting, and traumatic brain injury or even bone fracture may occur if the patient is not protected during the fainting attack.
Aspiration pneumonia
Aspiration may occur during an attack, resulting in aspiration pneumonia and coughing.
Consultation
Department of Medicine
Emergency Department
For symptoms such as fainting, loss of consciousness, convulsions, etc., it is recommended to call 120 emergency immediately or go to the emergency department of the hospital.
Cardiovascular Medicine
After the occurrence of A-s syndrome due to malignant arrhythmia caused by the patient’s comorbid cardiogenic diseases, the cardiology department should be requested to consult for the treatment of coronary artery disease, severe arrhythmia and other etiological factors on the basis of the emergency medical rescue.
Neurology or neurosurgery
For patients who have had an episode of ASC syndrome caused by cerebral hemorrhage or cerebral infarction, it is recommended to request a consultation with neurology or neurosurgery for intracranial lesions in addition to emergency care.
Preparation for medical treatment
Preparing for the consultation: registration, preparation of documents, and frequently asked questions
Tips for seeking medical treatment
If you experience fainting, sudden collapse, numbness of the limbs, or speech impediment, it is recommended that you go to the hospital immediately or call the 120 emergency number.
During the process of calling the emergency number, you should accurately describe the location, the current state of the patient and other key information, and listen to the instructions of the first-aiders.
For those who suffer from coronary heart disease, severe arrhythmia, or are taking anti-arrhythmic drugs such as amiodarone, it is recommended that they seek immediate medical attention if they experience a feeling of dizziness, nausea, abdominal discomfort, pallor, or limb weakness.
Checklist for medical preparation
症状清单
Pay particular attention to the time of onset of symptoms, special manifestations, etc.
How long did the syncope or collapse last?
Is the syncope accompanied by twitching of the limbs? How did the twitching of the limbs manifest itself? Duration?
Did the patient have palpitations and shortness of breath before the onset of syncope?
Did the patient have headache, projectile vomiting, etc. before the onset of syncope?
Did the patient present with pallor, limb weakness, etc. before the onset of symptoms? If so, time of first appearance? Duration of symptoms?
病史清单
Is there any previous history of coronary heart disease, heart failure, or other cardiac disease such as cardiomyopathy or congenital heart disease?
Any previous history of cardiac arrhythmias such as supraventricular tachycardia, ventricular tachycardia, atrioventricular block, etc.?
Any past history of chronic diseases such as hypertension, diabetes, etc.?
Any history of ionic disorders such as hyperkalemia or hypokalemia?
Any history of cerebral hemorrhage or cerebral infarction?
Any previous trauma, especially head trauma?
检查清单
Test results in the last six months to bring to the doctor’s office
Laboratory Tests
Blood biochemistry, blood routine, urine routine, myocardial injury markers, BNP or NT-ProBNP.
Imaging tests
Echocardiogram, head CT and/or head magnetic resonance imaging (MRI), coronary CT angiography coronary angiography.
Electrocardiogram (ECG)
用药清单
Medication use in the last 3 months, bring medication box or package with you to the doctor’s office if available
Any recent antiarrhythmic medications such as amiodarone, sotalol, etc.?
Have you recently taken a potassium-removing diuretic such as furosemide?
Have you recently taken any digitalis-based anti-heart failure drugs such as digoxin?
Have patients with hypertension taken antihypertensive drugs, such as irbesartan and nifedipine, on a regular basis?
Are patients with coronary artery disease taking antiplatelet drugs, such as aspirin and Tegretol, as prescribed by the physician?
Diagnosis
A.S. syndrome can be diagnosed based on history, symptoms and physical examination, and is not difficult to diagnose because of its typical symptoms; for those whose diagnosis is not clear, auxiliary tests such as electrocardiograms and blood tests can be used to help establish the diagnosis.
Diagnosis is based on
Medical history
Past history of severe arrhythmia, coronary artery disease, heart failure, cardiomyopathy, pre-coronary artery disease, viral myocarditis.
Recently taking antiarrhythmic drugs such as amiodarone or potassium-removing drugs such as furosemide.
No recent regular use of antihypertensive drugs as prescribed by the physician.
Clinical manifestations
症状
Sudden onset of syncope, failure to respond to call.
Fainting may be followed by twitching of the limbs.
For A. S. syndrome due to intracranial lesions such as stroke, symptoms such as dizziness, limb immobility, severe headache, and projectile vomiting may occur before fainting.
体征
Carotid artery pulses are weak or nonpalpable.
Pulse is fine or not palpable.
Heart sounds are absent and blood pressure is not measurable.
Voluntary respiration and thoracic movements are absent.
Face color and nail beds are pale.
Pupils are dilated and direct and indirect light reflexes are absent.
Laboratory tests
血常规
White blood cell count, neutrophil count, red blood cell count, platelet count, and hemoglobin concentration are checked.
This can prepare for treatment or rule out other diseases.
血生化
Test liver function, kidney function, fasting blood glucose, blood sodium ions, potassium ions, total cholesterol, triglycerides, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, cardiac enzymes, homocysteine and so on.
It can clarify the cause and severity of the disease, prepare for treatment, or rule out other diseases.
尿常规
Detecting protein, glucose, sediment, etc. in the urine.
Can prepare for treatment or rule out other diseases.
心肌损伤标志物
Includes cardiac troponin I (cTnI) or T (cTnT), creatine kinase isoenzyme (CK-MB), and myoglobin (Myo). Check for the presence of cardiomyopathy and the severity of the lesion.
Abnormalities occur in the event of a myocardial infarction, are used to establish a diagnosis, and can determine the severity of the condition.
利钠肽水平（BNP、NT-ProBNP）
It is an important indicator in the diagnosis of heart failure, patient management, and risk assessment of clinical events.
A normal natriuretic peptide level in an untreated person can largely rule out a diagnosis of heart failure, while a high natriuretic peptide level in a treated person suggests a poor prognosis.
Renal insufficiency, cirrhosis, infection, sepsis, and advanced age can all cause elevated natriuretic peptide, so its specificity is not high.
Imaging
心电图
Electrocardiography is preferred and the most basic test.
Electrocardiogram can see high or III degree atrioventricular block, sinus bradycardia, sinus block, cardiac arrest, ventricular fibrillation, ventricular tachycardia, fast atrial fibrillation and other cardiac rhythm abnormality manifestations.
Criteria suggestive of arrhythmogenic syncope:
心脏停搏超过3秒。
快速室上性心动过速。
室性心动过速。
晕厥发作时无心律失常可以排除心律失常导致的晕厥。
冠脉造影或冠脉CT血管成像
A definitive diagnosis of coronary artery disease can be made, but it needs to be made after vital signs have stabilized.
Visible narrowing or occlusion of coronary vessels.
心脏彩超
Can be used to understand the structure and function of the heart and to see if there is a possible cause of syncope.
Has diagnostic value for cardiac tamponade, cardiomyopathy, and heart valve disease.
颅脑CT或核磁共振。
It can be used to diagnose patients with stroke.
Examination reveals abnormal edema of the brain tissue or blood filling in the cerebral sulcus.
Differential diagnosis
Seizures.
共同点
Seizures often result in trauma with convulsions, upward rolling of the eyes, incontinence, lip biting and loss of consciousness. The duration of unconsciousness often lasts a few minutes and the seizure is followed by a prolonged lethargic state.
不同点
The onset of A.S. syndrome is slower than epilepsy and unpredictable, with brief seizures, rapid return of consciousness, and no postictal lethargy.
Hysteria
共同点
Sudden onset, failure to respond to calls, shaking of limbs and loss of consciousness.
不同点
Dysthymia is often not accompanied by changes in blood pressure, heart rate or skin color, and vital signs are stable.
Hypoglycemia
共同点
Presence of profuse sweating and loss of consciousness.
不同点
Hypoglycemic episodes are preceded by hunger, rapid heartbeat, nervousness, and other symptoms of sympathetic stimulation. Diagnosis is confirmed by an emergency examination showing low blood glucose.
Treatment
The goals of treatment for A-syndrome are to rapidly restore circulatory function, restore a cardiac rhythm with effective blood removal, and prevent recurrence. In addition to treating the cause of the underlying heart attack, it is also important to prevent predisposing factors, and the main therapeutic measure is to prevent and treat the arrhythmia that causes the syndrome.
Treatment principle: immediate first aid, vital signs stabilization and active treatment of the original disease.
Treatment objective: to restore the independent heartbeat and respiration, to relieve cerebral ischemia and hypoxia, and to prevent the recurrence of heart attack.
First aid measures
Cardiopulmonary resuscitation
When the patient is found to have fainted, first assess the patient’s vital signs, and immediately perform on-site cardiopulmonary resuscitation (CPR) after diagnosing A.S.S. syndrome.
During resuscitation, attention should be paid to the position, frequency and depth of pressure, to keep the airway open, and pay attention to cleaning abnormal secretions in the mouth and nose to prevent vomiting and asphyxiation.
It should be noted that cardiopulmonary resuscitation should be performed under the guidance of trained personnel, and cardiopulmonary resuscitation is prohibited if the patient’s heartbeat and respiration are spontaneous.
General Treatment
Upon receiving the patient, hospital or pre-hospital emergency personnel should rapidly administer oxygen, establish intravenous access, monitor vital signs with cardiac monitoring, and observe changes in cardiac arrhythmia.
Electrical cardioversion
Cardiac electrical cardioversion is an important measure to rescue A.S. syndrome.
Asynchronous electrical cardioversion is mainly used for ventricular fibrillation resuscitation or reversal.
Synchronized electrical cardioversion is mainly used for rescue or reversal of all kinds of ectopic tachyarrhythmias other than ventricular fibrillation, such as atrial fibrillation, atrial flutter, paroxysmal supraventricular tachycardia, and so on.
Contraindications:
洋地黄过量所致的心律失常。
严重低钾血症。
房颤、房扑伴高度或完全性房室传导阻滞。
病态窦房结综合征。
近期有血栓栓塞史。
已用大量抑制性抗心律失常药物。
Drug therapy
异丙肾上腺素
It should be used mainly in slow-type arrhythmias combined with A. S. syndrome.
A-s syndrome due to myocardial infarction is generally contraindicated because it tends to cause ventricular tachycardia, ventricular fibrillation and other fatal arrhythmias.
肾上腺素
It is mainly used in the rescue of ventricular fibrillation and ventricular arrest.
It is the drug of choice for resuscitation of cardiac arrest.
升压药
Norepinephrine, dopamine and other antihypertensive drugs can be given to maintain blood pressure in severe hypotension.
抗心律失常药物
Commonly used drugs such as amiodarone are usually applied when electrical cardioversion is ineffective. Certain refractory polyventricular tachycardia, ventricular fibrillation, etc. can be applied intravenously with beta-blockers. Magnesium sulfate is only indicated for interterminal torsion type ventricular tachycardia.
Etiologic treatment
Cardiovascular disease
冠心病
Depending on the patient’s coronary artery lesions, the treatment varies.
In less severe cases, secondary prevention of coronary artery disease should be carried out, and oral antiplatelet drugs such as aspirin and lipid regulating drugs such as atorvastatin should be taken. Risk factors should be actively controlled and regular checkups should be conducted.
In severe cases, coronary angiography should be performed in a timely manner, and stent implantation and coronary artery bypass grafting surgery should be performed if necessary. After the surgery, antiplatelet drugs such as aspirin and tegretol, statins and nitrates should be taken regularly. Regular follow-up.
心律失常
Arrhythmias of various causes may lead to an attack of A-s syndrome, and antiarrhythmic therapy should be administered in addition to active treatment of the primary cause.
Commonly used drugs for the treatment of tachyarrhythmias include propranolol, amiodarone, lidocaine, verapamil, etc. Commonly used drugs for the treatment of bradyarrhythmias include atropine, isoproterenol, etc.
The indications and contraindications for each drug are different and should be standardized in accordance with medical advice.
急性心力衰竭
Sitting position, legs down, oxygen sedation treatment.
With the use of diuretics, aminophylline, digitalis drugs.
It also includes the use of nitrates such as sodium nitroprusside and positive inotropic drugs such as levosimendan.
In addition to this, severe patients may be treated with mechanically assisted circulatory support devices.
慢性心力衰竭
Weight monitoring, low-salt and low-fat diets, controlling bad moods, understanding the triggers for the onset of the disease, regular rest and relaxation, and aggressive treatment for patients with primary diseases are required.
Pharmacological treatment includes diuretics, renin angiotensin aldosterone system inhibitors, β-receptor antagonists and positive inotropic drugs. Representative drugs include furosemide, sacubitril valsartan, metoprolol, spironolactone, digoxin, and dagliflozin.
Non-pharmacological treatments include cardiac resynchronization therapy, implantable cardioverter-defibrillator, left ventricular assist device, and heart transplantation therapy.
高血压
Patients with primary hypertension should actively carry out lifestyle intervention, and poor blood pressure control can be combined with antihypertensive drug therapy, such as nifedipine, irbesartan, enalapril, and so on. Start with small doses, give priority to long-acting preparations, combined medication and individualized treatment.
Patients with secondary hypertension should have a clear cause and be treated for the cause, such as renal vascular hypertension, primary aldosteronism, pheochromocytoma, and aortic constriction can be selected for surgical as well as interventional treatment.
Intracranial diseases
Cerebral hemorrhage, acute cerebral infarction, craniocerebral trauma and other diseases lead to the attack of A.S. Syndrome mainly due to intracranial hemorrhage, edema, traumatic brain tissue contusion, fracture bone fragments and other compression of the vital center, resulting in cardiac arrest, and then cardiogenic cerebral blood supply insufficiency.
Therefore, the treatment should actively relieve the compression and lower the cranial pressure, commonly used drugs include mannitol, furosemide, etc., and hypertensive patients should control their blood pressure. Patients with large bleeding volume should be punctured and drained in time or craniotomy should be performed to remove hematoma, and those with acute cerebral infarction should actively open the criminal blood vessels.
Others
Actively correct electrolyte disorders, pacemaker malfunction should promptly replace the pacemaker, electrode detachment should promptly reset the electrodes or replace the electrodes, food or drug poisoning should immediately stop eating, the nearest emergency medical care, active gastric lavage, inducing vomiting, application of detoxification drugs, blood purification, etc.
Surgical treatment
Implantable cardioverter defibrillator (ICD)
ICD is an electronic device to terminate fatal arrhythmia. Defibrillation electrodes are placed in the endocardium during surgery, which can sense excessive ventricular rate and ventricular fibrillation and discharge in time to terminate the arrhythmia, which can effectively prevent the attack of A.S. Syndrome and sudden death.
Cardiac Pacing Therapy
Permanent pacemaker implantation can significantly improve the slow heart rate and insufficient ejection volume of the heart, and can effectively prevent the recurrence of A.S.D. in the presence of a slow arrhythmia such as sick sinus node syndrome or complete atrioventricular block.
Cardiac Resynchronization Therapy (CRT-D)
The combination of biventricular synchronous pacing and ICD is called cardiac resynchronization therapy, which can significantly improve the ejection function of the heart in patients with severe heart failure, identify and terminate malignant arrhythmias, effectively prevent the attack of A. S. Syndrome, and reduce the mortality rate of patients with severe heart failure.
Catheter radiofrequency ablation therapy
All kinds of tachyarrhythmias with frequent episodes, obvious symptoms and difficult to control by drugs can be treated with catheter radiofrequency ablation if they meet the indications and have no contraindications [5-7].
Prognosis
Cure
Timely and urgent administration of correct emergency treatment can reduce the mortality rate and improve the prognosis of patients.
With active treatment of the primary disease and adjustment of daily living habits, some patients can realize long-term seizure-free A.S. syndrome.
Harmfulness
A.S.S. is one of the most common and dangerous emergencies in clinical practice, and the mortality rate is extremely high if it is not treated in time.
Daily
Daily Management
Dietary management
Abstain from alcohol.
Eat a light diet rich in fresh fruits and vegetables, soy products, grains, and foods rich in dietary fiber.
Avoid beverages such as coffee, strong tea, and energy drinks.
Life Management
Pay attention to the combination of work and rest, regular life, ensure sufficient rest and sleep.
Maintain optimistic and stable emotions and avoid strenuous exercise.
Keep bowel movement smooth and avoid straining to defecate.
Quit smoking and avoid inhaling second-hand smoke.
Family Guidance
Instruct family members to master the methods of primary cardiopulmonary resuscitation.
Inform family members that they should not feed or water the patient during syncope, and should not sit up or stand up immediately after consciousness is clear.
Elderly patients are prone to serious head and limb trauma during syncope and should avoid activities alone.
Instruct the patient to follow the doctor’s instructions for regular follow-up.
Prevention
For those who suffer from coronary heart disease, severe arrhythmia, heart failure, hypertension and other diseases, it is recommended to actively carry out treatment, and pay attention to take relevant medications as prescribed by the doctor, follow up regularly, do a good job of daily management, and improve medication adherence.
Immediate on-site cardiopulmonary resuscitation (CPR) during an attack and after cardiac arrest is the key to saving the patient’s life. Family members are advised to learn the correct CPR procedure and receive professional training.
When taking drugs such as amiodarone, furosemide, digitalis, etc., strictly follow the doctor’s instructions for medication as well as review, do not make unauthorized adjustments.
Change your lifestyle, maintain a regular routine, avoid staying up late, get enough sleep, quit smoking and drinking, and avoid coffee and strong tea.
For obese people, it is recommended to carry out scientific weight reduction and regular diet under the guidance of professional physicians in a timely manner, so as to control the weight in the ideal range.
If necessary, families can be equipped with portable external defibrillators.
Most of the A-s syndromes are related to various heart diseases, and early detection and active treatment of primary heart diseases can prevent the occurrence of A-s syndrome [8-11].
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