Aortic dissection (AD), also known as aortic dissection aneurysm, is a seriousCardiovascular emergency。When there is a break in the intima of the artery wall, blood enters the artery wall through the break to form a hematoma, and further strips the intima and media of the aorta, aortic dissection will occur.The recognized pathogenesis is caused by the structural and hemodynamic abnormalities of the aortic media itself, and the high-risk groups includeHypertension, older patients, patients with aortic atherosclerosis and hereditary vascular disease, etc.The disease progresses rapidly, with high early mortality, and the incidence is related to the growth of the population age.
Most patients will have sudden severe chest pain and other symptoms, and may have symptoms similar to shock such as pale face, sweating, wet and cold skin of limbs and poor perfusion. Some patients may have syncope or confusion with other diseases such as disturbance of consciousness. Therefore, it is necessary to conduct detailed medical history inquiry and physical examination for possible patients.
For the treatment of aortic dissection, effective analgesia and control of blood pressure and heart rate are first required to reduce the risk of aortic rupture.According to different disease states and types, some patients with severe conditions need active surgical treatment to prevent accidents such as aortic rupture and cardiac tamponade, while patients with mild conditions can choose drug tactics for treatment.In addition, patients need to be treated in strict accordance with the doctor's treatment plan and doctor's advice. Timely treatment is the key to improve the prognosis.
At present, aortic dissection is still under continuous research and exploration, including etiology, diagnosis and treatment strategies, which is an important topic of continuous concern and research in the medical community.
TCM disease name
Aortic dissection
Foreign name
aortic dissection
Alias
Aortic dissecting aneurysm
Visiting department
Cardiothoracic surgery, emergency department, chest pain center
Multiple population
A population with an average age of 51 years, male, with Marfan syndrome
Common location
aorta
Common causes
Aortic tunica media structure abnormality, hemodynamic abnormality, hypertension, atherosclerosis, hereditary vascular disease, aortitis disease, local infection or trauma of aorta, idiopathic degenerative changes of aortic tunica media
common symptom
Sudden severe chest pain, neck, pharynx, jaw pain, scapular pain, abdominal and lower limb pain
At present, for aortic dissection, the epidemiological research data based on demography is insufficient, and the disease is developing rapidly, with high early mortality. Some patients died before seeking medical advice, and there are also misdiagnoses, which makes it difficult to obtain the exact true incidence.
The annual incidence rate of the disease in Taiwan is about 4.3 per 100000, similar to that in Europe and the United States. There is no epidemiological result of the annual incidence rate in the mainland.However, relevant reports show that the average age of Chinese patients is 51 years old, of which men account for about 3/4, especially in patients with Marfan syndrome.
clinical stages
According to the duration of the disease, aortic dissection can be divided into acute phase (≤ 14 days), subacute phase (15-90 days), and chronic phase (>90 days).
Type I: The primary break is located in the ascending aorta or aortic arch, and the dissection involves most or all of the ascending thoracic aorta, aortic arch, descending thoracic aorta, and abdominal aorta.
Type II: The primary rupture is located in the ascending aorta, with dissection involving the ascending aorta and a few involving the aortic arch.
Type III: The primary rupture is located at the distal end of the left subclavian artery. Type IIIa refers to those whose dissection is limited to the descending thoracic aorta, and type IIIb refers to those who simultaneously involve the abdominal aorta.
The dissection involving the ascending aorta is Stanford A type, and only involving the descending thoracic aorta and its distal part is Stanford B type.
Sun's refined typing
Based on Stanford's classification, a more detailed classification was made, which can reflect the degree of lesion and prognosis of aortic dissection, and guide clinicians to develop personalized treatment plans according to the patient's conditions.At present, it is widely used in China.
Atypical variation
Aortic intramural hematoma (IMH)
The difference between IMH and typical aortic dissection is that there is no aortic intimal rupture, but IMH can secondary aortic dissection. The course of disease is similar and the treatment principle is basically the same.
Transmural atherosclerotic ulcer
A focal lesion located on the surface of the intima of the aortic lumen.Its natural course is changeable, and it is easy to secondary aortic dissection or perforation.
pathogeny
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The occurrence of aortic dissection is the result of the vicious circle caused by the interaction between the abnormal structure of the aortic tunica media itself and the abnormal hemodynamics.
Pathogenesis
Due to various reasons such as aging, the compliance of aortic vascular wall may decline, which is also known as the poor elasticity of blood vessels.At this time, the pressure caused by the blood flow in the vessel on the vessel wall will also increase, which will further damage the vessel wall, causing a break in the inner wall of the aortic vessel.Blood flows from the breachVascular wallAnd finally form aortic dissection.
Predisposing factors
Hypertension and the elderly
Hypertension is the most important risk factor for aortic dissection.It has been reported that 50.1%~75.9% of patients with aortic dissection have a history of hypertension.
The incidence of aortic dissection is significantly higher in a variety of uncontrolled hypertension patients.In addition, the incidence of this disease increases with age, which may be related to the abnormal structure of vascular wall caused by age.
When the intima of atherosclerotic plaque ruptures in patients with aortic atherosclerosis, it is easy to lead to aortic dissection, especially in patients with long-term smoking, dyslipidemia, diabetes and other diseases.
Hereditary angiopathy
The risk of aortic dissection in patients with Marfan syndrome is significantly increased. Other hereditary vascular diseases, such as aortic valvular malformation, congenital coarctation of aorta, can increase the risk of aortic dissection.
Aortitis disease
Such as giant cell arteritis, Takayasu arteritis, Behcet's disease, syphilis, etc.
Local infection or trauma of aorta
Infection of surrounding aortic tissue, endocarditis caused by infection of aortic valve replacement, trauma such as traffic accident and falling, iatrogenic injury caused by interventional treatment or heart and great artery surgery can all cause aortic injury and increase the risk of aortic dissection.
50% of the female patients who developed the disease before the age of 40 years occurred during pregnancy or postpartum, and those with Marfan syndrome or aortic root dilatation had a higher risk.
Idiopathic degenerative changes of aortic media
The risk of dissection is significantly increased due to the degeneration of aortic tunica media, structural changes of the aorta, and vascular wall breaks.
symptom
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The clinical manifestations of this disease are varied, and most patients have sudden severe chest pain symptoms.If the condition is complex or the patient is old, the symptoms are more atypical.
Typical symptoms
Most patients begin with acute severe chest pain.The nature of pain is mostly knife cut, acupuncture or tearing, which is usually persistent and unbearable. The treatment effect of morphine and other opioid analgesics is also not ideal.
The main part of pain is related to the location where the dissection occurs:
When the proximal ascending aorta and aortic arch are involved, neck, pharynx and jaw pain may occur;
When the dissection is located in the descending aorta, it usually presents pain in the scapular region. The formation of abdominal aortic dissection can cause pain in the back, abdomen and lower limbs;
If pain migrates, it indicates the progress of dissection;
If lower limb pain occurs, it indicates that lower limb arteries may be involved.
Accompanying symptoms
Some patients may have symptoms similar to shock, such as pale face, sweating, wet and cold skin of limbs and poor perfusion, but few patients actually have shock.
Syncope or disturbance of consciousness can also occur, and some patients even take syncope as the first symptom.
The disease progresses rapidly with high early mortality.Timely seek medical advice when symptoms occur to avoid delaying the best time for treatment.
After the patient goes to see the doctor, the doctor will conduct medical history inquiry and physical examination. For patients with high-risk medical history and typical manifestations, the doctor will timely arrange auxiliary examinations to help clear the diagnosis.
Visiting department
Cardiothoracic surgery is the first choice.
In case of sudden severe chest pain and other suspicious symptoms, you can go to the emergency department for medical treatment.If there is a chest pain emergency in a nearby hospital, you can go directly to see a doctor.
Relevant inspection
physical examination
The blood pressure of the limbs of patients with aortic dissection varies greatly, because the patients may have hypertension, but when the measured limb is the affected side of aortic dissection, it is easy to be misdiagnosed as hypotension, and the blood pressure of the limbs should be measured routinely;
Cardiac auscultation may cause diastole murmur in aortic valve area;
When a large amount of exudation or bleeding occurs in aortic dissection, if the blood enters the thoracic cavity, the trachea may move to the right and the left respiratory sound may be weakened;
In case of acute left heart failure, both lungs can be heardMoist rale；
When other system symptoms are complicated, corresponding signs may appear.
laboratory examination
For patients with high suspicion of aortic dissection, the three routine examinations of blood, urine and stool, liver and kidney functions, blood gas analysis, myocardial enzymes, myoglobin, blood coagulation function and blood lipids should be improved to help differential diagnosis and assess organ function and operation risk.
D-dimer is very important for the diagnosis and differential diagnosis of aortic dissection (AD).
Echocardiography
Transthoracic echocardiography (TTE)
The diagnostic accuracy of TTE in diagnosing AD is slightly lower than that of CT and MRI, but it can be used as a preliminary assessment method because of its portability and non-invasive.TTE can detect the expansion of the aortic root and the formation of false lumen in the aortic wall at the dissection, and can also troubleshoot complications such as cardiac tamponade and aortic valve insufficiency.
Transesophageal echocardiography (TEE)
The sensitivity and specificity of TEE in the diagnosis of aortic dissection are relatively high, but it is not a routine examination for invasive operation and patient cooperation.
The examination can find the dissection lesions located at the end of the ascending aorta, the aortic arch and the descending aorta, and can show the location of the intimal tear and the blood flow of the true and false lumens.
Computed tomography (CT)
The diagnosis of aortic dissection is highly sensitive and specificCT angiographyCTA can be the first choice of preoperative examination for suspicious patients.
CTA can clearly show the free intimal segment and the true and false double lumen sign of aortic dissection, and the examination is completed quickly, which is suitable for critical patients.This examination is prohibited for those allergic to iodine contrast medium.
For patients who are not suitable for CTA examination, such as iodine allergy, renal function damage, pregnancy, hyperthyroidism and other reasons, MRI can be the first alternative.
MRI can obtain images of the aorta from multiple planes, and its accuracy in diagnosing aortic dissection is comparable to that of CT, and it plays a significant role in differentiating aortic intramural hematoma (IMH) and penetrating aortic ulcer (PAU).Magnetic resonance angiography (MRA) can more accurately assess the location, extent and severity of lesions.
The examination takes a long time and is not applicable to patients with unstable hemodynamics. It is prohibited for patients who have received metal implants.
Aortography
The accuracy of angiography in the diagnosis of aortic dissection is more than 95%, which was once considered as the "gold standard" for the diagnosis of aortic dissection.This examination can show the location, scope, entrance, exit of intimal tear, and the involvement of aortic branches and aortic valves.
Angiography is an invasive operation with risks, so it is not used as a routine inspection method.
X-ray chest film
It can show widening of aorta, irregular or even distorted outer contour of aorta, displacement of calcification shadow of aortic intima, etc.However, a small number of patients with aortic dissection showed normal chest radiographs.
Most of the patients with aortic dissection showed nonspecific ST-T changes in ECG, but about 1/3 of the patients also showed completely normal ECG.Myocardial ischemia or myocardial infarction may occur when coronary artery is involved, which should be differentiated from acute coronary syndrome, especially acute ST segment elevation myocardial infarction.
Myocardial infarction usually presents with gradually increasing pain in the posterior sternum or precordial region, which can radiate to the left upper limb or left shoulder;
Acute myocardial infarction usually has typical ECG manifestations, and myocardial enzymes and other markers will also show typical changes;
Both patients with aortic dissection and acute myocardial infarction may have symptoms similar to shock, such as pale face, clammy limbs and sweating, but when combined with the above symptoms, the latter is often accompanied by hypotension, while the former is generally not low in blood pressure;
Echocardiography and spiral CT are helpful to diagnose aortic dissection.
When the abdominal aorta and its branches are involved, patients may have clinical manifestations similar to acute abdomen, such as nausea, vomiting, abdominal pain, bloody stool, etc., which are easily misdiagnosed as acute pancreatitis, acute cholecystitis, peptic ulcer perforation and other diseases.The doctor can differentiate the patient by understanding the pain characteristics of the patient in detail, observing whether the patient's blood pressure and pulse are abnormal, and combining with imaging examinations such as echocardiography.
Aortic valve insufficiency caused by other reasons
Perforation of aortic valve and rupture of aortic sinus aneurysm caused by infective endocarditis can cause acute aortic insufficiency with acute left dysfunction, but generally there is no sudden severe chest pain, and there is no branch vessel involvement, which can be distinguished according to the imaging examination results.
other
Aortic dissection should also be differentiated from acute pericarditis, acute pulmonary embolism, pneumothorax, stroke and other emergencies. Doctors will judge from clinical manifestations, examination results and other aspects.
treatment
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The acute onset and rapid progress of aortic dissection (AD) require prompt emergency treatment. After that, the diagnosis and classification should be clarified as soon as possible, and the corresponding treatment scheme should be selected.The initial treatment principle is to effectively relieve pain, control blood pressure and heart rate, reduce aortic pressure, and reduce the risk of aortic rupture.
Acute treatment
Patients with suspicious symptoms and high suspicion of aortic dissection should be promptly sent to the cardiac care unit to ensure absolute bed rest, avoid exertion and ensure smooth stool;
Closely monitor the vital signs of patients and give them oxygen inhalation to maintain;
Patients with unstable hemodynamic parameters should be ready for tracheal intubation at any time.
Once acute Stanford A AD is found, emergency surgical treatment should be performed.
Acute Stanford B AD can be discharged from hospital after treatment mainly through drug analgesia, blood pressure reduction, reduction of ventricular contractility and heart rate.
medication
analgesia
Doctors usually give appropriate opioid drugs (such as morphine, pethidine, etc.) intramuscular injection or intravenous application.
Relieving pain symptoms can improve the control effect of blood pressure and heart rate, and at the same time, it can properly soothe patients' emotions.
Control heart rate and blood pressure
The risk of aortic rupture can be reduced by controlling the left ventricular systolic pressure and heart rate. The goal of drug treatment is to control the systolic pressure at 100~120mmHg and stabilize the heart rate at 60~80 beats/minute.
The most basic and preferred antihypertensive drugs are beta blockers (such as metoprolol, esmolol, etc.). When the antihypertensive effect is not obvious, they can be combined with other antihypertensive drugs.
In clinic, intravenous beta blocker is often used in combination with sodium nitroprusside.However, when the heart rate is not well controlled, nitroprusside cannot be used to avoid the release of reflex catecholamines (epinephrine, norepinephrine, dopamine), which will increase the aortic pressure and worsen the condition.
IntolerableBeta blockerNon dihydropyridine calcium channel antagonists can be replaced by intravenous injection in 30% of patients.
surgical treatment
Different types of aortic dissection usually use different surgical methods.
Stanford type A aortic dissection
Once found, they should be actively treated with surgery.It is mainly to prevent aortic rupture, cardiac tamponade and other critical conditions, and at the same time, it can correct aortic insufficiency, improve hemodynamics, repair organ perfusion, and reduce patient death.
On the basis of good arterial intubation and brain protection, medical staff will carry out reconstruction treatment of aortic arch and root.The commonly used operations include Bentall operation, Wheat operation, ascending aorta transplantation and subtotal aortic arch transplantation.
Female patients with pregnancy are relatively rare. Such patients should be treated according to the principle of diagnosis and treatment in the acute phase, focusing on saving the mother's life, and quickly combined with multiple departments for diagnosis and treatment.
Stanford B aortic dissection
The degree of danger is low. Drug treatment is the basic treatment for such patients. Only some complicated or special types of Stanford B aortic dissection (AD) need surgical treatment.
For acute non complex Stanford B AD, if there is no complication, the best drug treatment can be used. Whether surgical treatment is based on this is still controversial;
Endovascular treatment is the first choice for acute complexity Stanford B AD, and endovascular repair of thoracic aorta can be adopted. Other surgical methods include direct vision stent elephant nose surgery, Hybrid surgery, etc. The clinician needs to select specific surgical methods according to the patient's situation;
If there is a thoracoabdominal aortic aneurysm in chronic Stanford B AD patients with a diameter ≥ 5.5 cm, it is recommended to use thoracoabdominal aortic replacement;
Special types of Stanford B AD, such as traumatic, iatrogenic, coarctation of aorta or arteritis, require surgical treatment.
TCM treatment
The TCM treatment of the disease is not supported by evidence-based medical evidence, but some TCM treatment methods or drugs can alleviate symptoms, so it is recommended to go to regular medical institutions and treat under the guidance of doctors.
prognosis
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The disease progresses rapidly, and the mortality rate of untreated patients is extremely high. Among them, 25% of patients die within 24 hours after the onset of the disease, and more than half of patients die within one week after the onset of the disease. The mortality rate of 1 month and 1 year after the onset of the disease is higher than 75% and 90% respectively.
At present, with the development of various treatment technologies, the 10-year survival rate of patients with aortic dissection is about 50%.
Aortic dissection has the following complications:
Stanford type A often involves the heart, and dissection is easy to be combined with severe aortic insufficiency, which can cause acute left heart failure;
Myocardial infarction may occur when coronary artery orifice is involved due to dissection;
When the innominate artery or left common carotid artery is involved, the patient may have cerebrovascular accidents, such as syncope, aphasia, lethargy, disturbance of consciousness, disorientation and contralateral hemiplegia;
When the dissection lesion involves the abdominal aorta trunk or mesenteric artery, the patient may have nausea, vomitingabdominal pain、Black stoolorBloody stoolIsosymptom;
When the dissection lesion involves the lower limb artery, the patient may have acute ischemic symptoms such as pain, no pulse or even ischemic necrosis.
Common postoperative complications include acute respiratory insufficiencyapoplexy、cerebral hemorrhage、renal failure, bleeding, infection, internal leakage andFlaccid paralysisOr paraplegia and other neurological complications, which should be actively treated according to the severity of the complications.
