Clinical Observation On The Treatment Of Stanford A Type Aortic Dissection

Background:Aortic dissection refers to the blood rush into the cracks of aortic intima and cause the separation of the arterial wall, it is one of the most common diseases of the aorta, the annual incidence rate is5～10/100000, the mortality rate of is about1.5/100,000. Aortic dissection is a dangerous disease with high mortality.The morbidity increase year by year in our country. The classification of aortic dissection is based on the anatomical location of the aortic intima’s cracks and the range involved.In1970, Stanford university’s Daily named that aortic dissection involved the ascending aorta was Stanford A type, had not involved the ascending aorta was Stanford B type. The prognosis of aortic dissection is poor, it shares a higher proportion of the entire cardiovascular mortality, Aortic dissection cause serious threat to human health and life. The main cause of death is aortic rupture and hemorrhage. Related treatment of the aortic dissection includs the following aspects: Medical therapy is the foundation of the whole treatment, the main purpose is to relieve pain、lower blood pressure and left ventricular ejection rate,it reduce the risk of aortic rupture and hemorrhage; Thoracic endovascular aortic repair (TEVAR) is mainly applied to Stanford type B aortic dissection; Surgery is the main treatment for the disease type A, the main purpose is to prevent the rupture of aortic cardiac tamponade and aortic regurgitation. Stanford type A aortic dissection is particularly dangerous and the mortality rate of type A patients is very high.The type A patients are younger in our country than other countries. Although the illness is complex and serious, they expect long life, the surgical treatment of type A AD is always faced with a huge challenge and controversy.According to aortic cracks and the involved range of aorta, different methods are adopted in surgery.Such as Bentall procedure、 Wheat procedure、Cabrol procedure、replacement of ascending aorta、aortic arch replacement、elephant truck technique、Sun’s procedure and hybrid technique such as "Debranching".The traditional open surgery should be carried out in deep hypothermie circulatory arrest and other auxiliary, The surgical procedures is complex and cause large trauma to patients, leading to a high incidence of perioperative complications, high mortality rate. The recovery of postoperative patients is slow. Although the anesthetic techniques and surgical instruments and experience of surgeon continuously make progress, but the effect of operation of Standford type A AD was not significantly improved, in-hospital mortality is still as high as10%to30%. In recent years, various types of hybrid technique carried out both at home and abroad and have achieved good therapeutic effect.This topic through observe different treatments for type A patients, to explore the appropriate solution for type A patients.Material and methods:Continuous receive the patient with type A in2008May to2014April for Stanford type A aortic dissection. They are all93cases. Intravenous antihypertensive drugs (such as urapidil, sodium nitroprusside, etc.) are pumped to all patients when they admitted to hospitaland the systolic blood pressure is controled to the100-120mmHg (1mmHg=0.133kPa). According to the generally conditions and aortic lesion’s conditions and the willing of patients and their families choose conservative medical treatment or surgical emergency surgery and limited surgery. After the patients were discharged, they took antihypertensive drugs and monitored the blood pressure daily for controling the blood pressure to120～140/80～90mmHg. Statistical in patients with clinical data, including:basic data, general situation, the major clinical manifestations, complications,the whole aorta computed tomographic angiography(aortic CTA) examination. To compare the effect of medical group without surgery with surgical group, traditional open surgery group with hybrid surgery groups.Groups according to the different treatment:medical group include38cases,surgery group include55case,66cases(70.97%) of male and27cases(29.03%) of female, the sex ratio is2.4:1. Aged21to83years, mean age50.60±7.47. Hypertension in76cases (81.72%).28cases(70.97%) of male and10cases(29.03%) of female in medical group, the sex ratio is2.8:1, mean age57.16±8.74. Hypertension in31cases (81.6%).1patient of Marfan syndrome,2cases of the history of cerebral infarction.1case of diabetes,3cases of coronary heart disease;7cases of respiratory dysfunction,4cases of pericardial tamponade and cardiac dysfunction.6cases of renal insufficiency.2cases of disturbance of consciousness. Surgery group were divided into hybrid group of31cases and the open group of24cases.38cases(71.7%) of male and17cases(28.3%) of female, the sex ratio is2.2:1. Aged21-73years, mean age46.06±6.61. Hypertension in45cases (81.8%).2cases of Marfan syndrome,1had previously underwent TEVAR due to Stanford type B aortic dissection three years ago.1patient with multiple injuries in a car accident.2cases of pericardial effusion (3.6%). All patients were confirmed having aortic dissection and dissected areas were determined with imaging methods of echocardiography and CT/MRI. According to aortic cracks and the involved range of aorta, different methods are adopted in surgery. All patients underwent surgery on cardiopulmonary bypass(CPB). Cardiac arrest was obtained by antegrade administration in the coronary ostia and retrograde administration into the coronary sinus with cold crystalloid cardioplegia. Deep hypothermie circulatory arrest(DHCA)and selective antegrade cerebral perfusion(SACP)through right subclavian(axillary)artery or/and left common carotid artery were performed in open group, Mild hypothermia circulatory and selective antegrade cerebral perfusion(SACP)through right subclavian(axillary)artery or/and left common carotid artery were performed in hybrid group. Open group:2cases of Bentall procedure,1case of replacement of ascending aorta, Bentall+total arch replacement+stented technique in the thoracic descending aorta in3cases. Ascending aortic graft+total arch replacement+stented technique in the thoracic descending aorta in8cases. Wheat+total arch replacement+stented technique in the thoracic descending aorta in9cases. Ascending aortic graft+hemi-arch replacement+coronary arterybypass grafting(CABG) in1cases. Hybrid groups:Bentall+total arch replacement+stented technique in the thoracic descending aorta in4cases. Ascending aortic graft+total arch replacement+stented technique in the thoracic descending aorta in17cases. Wheat+total arch replacement+stented technique in the thoracic descending aorta in7cases. Ascending aortic graft+hemi-arch replacement+coronary arterybypass grafting(CABG) in3cases. All patients had medical records and got the post-treatments information by telephone or clinic follow-up. The main contents include patients’ survival, blood pressure, aortic false lumen observed by aortic CTA and the clinical symptoms of patients,to evaluat recovery of patients. Statistical Methods:To collect and organize patients’clinical and follow-up data retrospectively. All data be entered into the database, Study the clinical traits, diagnosis method, risk factors and managements. The statistics were analyzed with SPSS18.0. The continuous variables were expressed as (X±S),and the categorical variables were presented as frequencies and percentages. Univariate analyses between groups were done using chi-square cross tabulations for categorical data and the Student t test for continuous data. All P values were two-sided, with values<0.05considered significant.Result:Medicine group:There are38cases of Standford type A AD be treated only by medical therapy.There are all kinds of reasons for they have not accepted surgical treatment.5cases of old-age and their disfunction of cardic and lung.2cases of disturbance of consciousness.7cases of respiratory dysfunction,6cases of renal insufficiency.9cases of heavy condition evolution is fastest and worsens suddenly,6cases of financial difficulty. There are30patients died in hospital for a week,l patient died after2years and7months since discharge. There are7patients still alive(1～196weeks),mean60.43±37.25weeks.The medical group’s mortality in hospital was79.0%,81.6%in four years.Surgery group:There are55cases of Standford type A AD be treated by surgical therapy. The overall mortality was9.1%. The details are as follows:Open Group:A total of24cases be classfied into open surgery group. Three cases (12.5%) died during surgery or after surgery, low output syndrome in2cases and multi-organ failure(MOF) in1case. Postoperative re-exploration for hemorrhage of anastomosis in2cases. Postoperative re-tracheal intubation for pulmonary infection in1case, Postoperative CRRT(continuous rena replacement therapy) for acute renal injury in1case,1case of cerebral infarction be improved after treatment. CPB time was119～563min,, with a mean of(206.79±87.26)min, Aortic cross elamp(ACC) time was36～287min, with a mean of(112.65±59.67)min. SACP and lower body arrest time was22～83min, with a mean of (28.51±13.45)min。operating time was7.62± 2.91hours. Transfusion of concentrated red blood cell was2-16U, with a mean of(6.04±3.82)U, of platelet was0-16U, with a mean of(7.12±2.93)U, of plasma was400～3600ml, with a mean of(1083.72±654.91)ml, of cold deposition was0-10U, with a mean of (3.51±2.39) U.Hybrid Group:A total of31cases be classfied into hybrid surgery group. Two cases (6.45%) died during surgery or after surgery, cerebral hemorrhage in1case and multi-organ failure(MOF) in1case. Postoperative re-exploration for hemorrhage of anastomosis in1case. Postoperative re-tracheal intubation for pulmonary infection in1case. CPB time was89-237min,, with a mean of(140.62±31.07)min, Aortic cross elamp(ACC) time was28-97min, with a mean of(50.93±16.21)min. operating time was6.59±1.47hours. Transfusion of concentrated red blood cell was2～10U, with a mean of(4.83±2.65)U, of platelet was0±16U, with a mean of (6.38±2.01)U, of plasma was400±1600ml, with a mean of(619.72±436.15)ml, of cold deposition was0～10U, with a mean of (3.27±2.11) U. During operation,hybrid surgery group is significantly less than open surgery group in CPB time> ACC time and the use of plasma (P<0.05、<0.01、0.002, separately)and less than open surgery group in the use of red blood cell platelet after operation(P=0.029、<0.05). Hybrid surgery group has lower hospital mortality rate and postoperative complications, though not significantly,may be the cases are too limited.The follow-upFor those patients(49cases) who had implanted stents during surgery and discharged, we observed the maximum diameter of aorta and the false lumen and true lumen in preoperative and postoperative2～4weeks,3-6months, and1-3years by CTA.2-4weeks after surgery, the maximum diameter of aorta is slightly larger than preoperative[(36.07±4.71) mm VS (36.45±4.13) mm, p>0.05],3-6months after surgery, the maximum diameter of aorta is significantly smaller than preoperative[(36.20±3.82) mm VS (29.73±4.06) mm, p<0.05],1-3years after surgery, the maximum diameter of aorta is significantly smaller than preoperative[(36.15±4.94) mm VS (29.97±5.37) mm, p<0.05];2-4weeks after surgery, the maximum diameter of false lumen has no obvious change compared with preoperative[(14.73±4.26) mm VS (14.32±4.27) mm, p>0.05],3-6months after surgery, the maximum diameter of false lumen is significantly smaller than preoperative [(15.06±4.41) mm VS (5.19±2.32) mm, p<0.05],1-3years after surgery, the maximum diameter of false lumen is significantly smaller than preoperative[(17.74±3.59) mm VS (3.17±2.25) mm, p<0.05], the false lumen is partial or complete thrombosis;2-4weeks after surgery, the maximum diameter of true lumen is significantly larger than preoperative [(21.34±4.83) mm VS (22.13±4.79) mm, p<0.05],3-6months after surgery, the maximum diameter of true lumen is significantly larger than preoperative[(21.14±5.01) mm VS (24.54±4.33) mm, p <0.05],1-3years after surgery, the maximum diameter of true lumen is significantly larger than preoperative[(18.41±2.84) mm VS (26.80±4.95) mm, p<0.05]. Patients’ descending aorta and false lumen diameter all showed a trend of decrease after stents had been implanted during surgery.Conclusion:1. Surgical is the first choice to treat Stanford type A aortic dissection.2. Hybrid Stanford compared with open surgery is more safe in the treatment of Stanford type A aortic dissection, and decrease the use of blood.3. TEVAR can can narrow false lumen and cause thrombosis in Stanford type A aortic dissection which involved descending aorta, short-term and mid-term outcome is favorable.