Acute Stanford Research Articles

Expression of matrix metalloproteinase-12 in aortic dissection.

BackgroundAortic dissection(AD) is an acute process of large blood vessels characterized by dangerous pathogenic conditions and high disability and high mortality. The pathogenesis of AD remains debated. Matrix metalloproteinase-12 (MMP-12) participates in many pathological processes such as abdominal aortic aneurysm, atherosclerosis, emphysema and cancer. However, this elastase has rarely been assessed in the presence of AD. The aim of the present study was to investigate the expression of MMP-12 in aortic tissue so as to offer a better understanding of the possible mechanisms of AD.MethodsThe protein expression levels of MMP-12 were analyzed and compared in aorta tissue and the blood serum samples by reverse transcription polymerase chain reaction(RT-PCR), Western blotting, immuno-histochemistry, fluorescence resonance energy transfer ( FRET ) activity assay and enzyme-linked immuno sorbent assay ( ELISA ), respectively. Ascending aorta tissue specimens were obtained from 12 patients with an acute Stanford A-dissection at the time of aortic replacement, and from 4 patients with coronary artery disease (CAD) undergoing coronary artery bypass surgery. Meanwhile, serum samples were harvested from 15 patients with an acute Stanford A-dissection and 10 healthy individuals who served as the control group.ResultsMMP-12 activity could be detected in both AD and CAD groups, but the level in the AD group was higher than those in the CAD group (P < 0.05). MMP-12 proteolysis existed in both serum samples of the AD and healthy groups, and the activity level in the AD group was clearly higher than in the healthy group (P < 0.05). For AD patients, MMP-12 activity in serum was higher than in the aorta wall (P < 0.05). MMP-12 activity in the aortic wall tissue can be inhibited by MMP inhibitor v (P < 0.05).ConclusionThe present study directly demonstrates that MMP-12 proteolytic activity exists within the aorta specimens and blood samples from aortic dissection patients. MMP-12 might be of potential relevance as a clinically diagnostic tool and therapeutic target in vascular injury and repair.

Application of Protective Stents in Endovascular Repair of Acute Complicated Stanford Type B Aortic Dissections

To describe the use of protective stents in the endovascular repair of acute complicated Stanford type B aortic dissections. From 2009 to 2011, 33 patients (27 men; mean age 47 years, range 31-73) with acute complicated Stanford type B aortic dissection underwent thoracic endovascular aortic repair (TEVAR) assisted by protective stents. In all cases, the proximal and distal landing zones differed in size by >5 mm, and the primary entry tear was in the proximal descending aorta. A bare self-expanding stent (protective stent) was deployed initially at the intended distal landing site of the primary stent-graft in the true lumen. The intention was that the bare stent would prevent excessive dilation of the distal end of the stent-graft in the vicinity of the entry tear, thus avoiding intimal rupture. Successful stent deployment and sealing of the entry tear was achieved in all patients. The median diameter and length of the protective bare stents was 20.3 mm (range 18-24) and 72.7 mm (range 60-80), respectively, while the corresponding dimensions of the covered stent-grafts were 32.8 mm (range 26-40) and 157.4 mm (range 120-200 mm), respectively. There was no stent twisting, migration, of rupture of the false or true lumen. Computed tomography 1 week postoperatively demonstrated closure of the primary entry tear with thrombosis of the false lumen in all cases. No patients were lost to follow-up, which has ranged from 3 months to 3 years. No late endoleaks or stent complications, such as angulation, dislodgment, persistent leaks, branch obstruction, or stent-graft migration, have been observed, and there has been no chronic progressive true or false lumen dilatation, recurrences, or deaths. Adjunctive use of a protective stent when treating acute Stanford type B aortic dissections in which the diameters of the proximal and distal landing zones differ by >5 mm is feasible and safe and provides good short-term outcomes.

Treatment strategies for left subclavian artery during total arch replacement combined with stented elephant trunk implantation

One of the technical challenges in total arch replacement for type A aortic dissection is the left subclavian anastomosis and the descending aortic anastomosis. We present a technique that simplifies this surgery. A total of 33 consecutive patients (mean age, 48.0 ± 11.6 years) with acute Stanford type A aortic dissection who underwent a total arch replacement were included in this study. Instead of anastomosing the graft to the descending aorta distal to the left subclavian artery, we ligated the left subclavian artery and performed the distal aortic anastomosis between the left carotid artery and the left subclavian artery. The left subclavian artery is then revascularized with a side arm from our aortic graft through the first intercostal space to the left axillary artery. The descending aorta also is stented in an antegrade fashion under direct visualization. Both intraoperative and postoperative complications were then noted. All enrolled patients underwent total arch replacement performed using this newly introduced technique with a mortality rate of 18.2% (6/33). The causes of mortality were multiorgan failure (4 patients), renal failure (1 patient), and postoperative sepsis (1 patient). There was no intraoperative death and no anastomotic leak in our study cohort. Limb ischemia was observed in 4 patients, with all occurring in the lower limb. Postoperative delirium also was observed in 5 patients. The left subclavian artery bypass technique during total arch replacement for type A dissection is reliable and simplifies the surgery by bringing the descending aortic anastomosis more proximal and eliminating the difficult left subclavian artery anastomosis.

Acute Stanford B aortic intramural hematoma: early and midterm follow-ups and morphological changes of computed tomography

To summarize the clinical performances and analyze the morphological characters of acute Stanford B aortic intramural hematoma (IMH) on computed tomography (CT). From January 2010 to June 2012, a total of 28 IMH patients at General Hospital of People's Liberation Army were retrospectively reviewed. Among them, 18 patients were followed up with CT. The data of vessel wall maximum thickness (MT), aortic maximum outside diameter (OD) and aortic inner diameter (ID) at onset and 1 week, 1, 3, 6, 12 months post-onset. Statistical analysis was performed with paired t-test. No mortality occurred. Two patients received endovascular repair. According to the follow-ups of 18 IMH patients, MT was (12.1 ± 2.6) mm on CT. Hematoma disappeared in 44.4% patients at 6 months post-onset. Hematoma disappeared more in the patients with MT ≤ 10 mm than those with > 10 mm (85.7% vs 18.2%, P < 0.01). Hematoma disappeared in 13/15 patients (86.7%) at 12 months post-onset. OD decreased (7.3 ± 2.4) mm per year and (6.7 ± 3.5) and (0.6 ± 1.7) mm within the first 6 months and 6 months later respectively. OD increased (0.9 ± 0.5) mm after the disappearance of hematoma. ID increased (6.1 ± 2.3) mm per year and (4.7 ± 1.8) and (1.2 ± 1.0) mm within the first 6 months and 6 months later respectively. The early and midterm outcomes of IHM are satisfactory most of hematoma disappear 12 months after onset. Hematoma disappears more rapidly in the patients with MT ≤ 10 mm than those with > 10 mm. OD reduces and ID increases before the disappearance of hematoma, and both increase afterward. Aortic cavity has a trend of dilating continually.

PP-227 ACUTE ANTERIOR MYOCARDIAL INFARCTION DUE TO AN ACUTE AORTIC DISSECTION INVOLVING THE LEFT MAIN CORONARY ARTERY

We report a case of anterior myocardial infarction due to a Stanford type A aortic dissection involving the left main trunk of the coronary artery. Acute myocardial infarction due to extension of an acute Stanford type A aortic dissection is a rare but lethal situation. A 54-year-old man with a history of hypertension was referred to our hospital with a sudden onset of severe chest pain which started one hour earlier. The ECG showed extensive ST-segment elevation in the anterior and lateral leads suggesting acute anterior myocardial infarction (Figure 1a). On physical examination general health situation was moderate. His heart rate was 98 bpm and blood pressure was 100/70mmHg. First and second heart sound was normal. There was no additional heart sound or murmur. Emergent coronary angiography demonstrated an aortic dissection located at the sinus of Valsalva and ascending aorta. The false lumen originated from the sinus of Valsalva and involved the left main coronary artery. Total occlusion of the left main coronary artery with TIMI 0 flow was seen (Figure 1b). The patient was transferred for emergency surgery. Postoperatively, an intra-aortic balloon pump was inserted because of haemodynamic instability due to the left ventricular myocardial injury. The patient discharged 21 days after surgery in good health status. Acute myocardial infarction due to extension of an acute Stanford type A aortic dissection is a rare but lethal situation. Several case reports of a Stanford type A aortic dissection in combination with a myocardial infarction have been published. In almost all cases the right coronary artery was involved. In our case a spontaneous aortocoronary dissection involving the left Valsalva sinus and the ascending aorta with a history of hypertension is the most plausible cause.

Marfan syndrome with antineutrophil cytoplasmic antibody-associated systemic vasculitis presenting as severe anaemia and haematuria after the Bentall procedure

One month previously, a 28-year old male underwent an emergency modified Bentall procedure because of Marfan syndrome with acute aortic dissection Stanford Class A. Computed tomography of the chest did not reveal severe graft stenosis of the anastomosis. To explore the cause of anaemia, renal dysfunction and macroscopic haematuria, the patient was tested for antineutrophil cytoplasmic antibody (ANCA)-associated systemic vasculitis (AASV). Antimyeloperoxidase antibodies (MPO)-ANCA and antiproteinase 3 antibodies (PR3)-ANCA were strongly positive. Corticosteroid therapy was applied, followed by cyclophosphamide and azathioprine. In response to treatment, the MPO-ANCA and PR3-ANCA levels gradually decreased, proteinuria was alleviated and haemoglobin levels returned to normal after 6 months. This is the first report to highlight haemolytic anaemia and AASV with Marfan syndrome after surgery for aortic dissection.

Application of Open Triple-Branched Aortic Arch Stent Graft for Acute Stanford Type A Aortic Dissection

Complete documentation is provided outlining a process for surgical treatment of the ascending aorta using open triple-branched aortic arch stent grafts to treat acute Stanford type A aortic dissection based on clinical observations. A total of 34 patients underwent replacement of the ascending aorta or aortic root in combination with open placement of a triple-branched stent graft. Mean cardiopulmonary bypass, mean myocardial ischemic, and selective cerebral perfusion times were 186 ± 38, 101 ± 27, and 39 ± 11 minutes, respectively. Two deaths occurred during hospitalization. Of the remaining patients, postoperative computed tomography angiography confirmed that all implanted stent grafts were fully opened; however, the dissected aorta and false lumen size showed evidence of reduced thickness. This applies mainly to those who need extensive surgical reconstruction of the thoracic aorta with acute Stanford type A aortic dissection, and it can reduce cardiopulmonary bypass complexities of the traditional surgeries and potential complication.

下肢虚血を合併した Stanford B 型急性大動脈解離に対する人工血管置換術後 MNMS の救命例

症例は52歳，男性．2011年9月，突然の胸背部痛と下肢の痺れを訴え当院に救急搬送された．CT検査でStanford B型急性大動脈解離と診断した．腎動脈以下の血栓化偽腔の圧排によって左総腸骨動脈の高度の狭小化を認めた．下肢の虚血解除を目的に緊急大腿動脈交叉（F-F）バイパス術を施行し左下肢の症状は消失した．しかし入院4日目に突然，両下肢の安静時痛およびチアノーゼが出現した．CT検査で血栓化偽腔の増大のために腎動脈下大動脈真腔が高度に狭小化していた．緊急開腹人工血管置換術を施行し，下肢血流の再還流をえた．術後血行再建後症候群（myonephropathic metabolic syndrome : MNMS）を併発し，急性腎不全に対して持続的血液濾過透析（CHDF）を行った．経過中に心室細動も発症し，術後管理に難渋したがその後，自尿を認め透析から離脱した．Ankle brachial pressure index（ABI）も改善し，入院34日目に麻痺なく独歩で退院した．

Aortic intramural hematoma after thrombolysis in a patient with acute massive pulmonary embolism

Aortic intramural hematoma after thrombolysis in a patient with acute massive pulmonary embolism

段階的に手術を施行した臓器虚血を伴った大動脈B型解離の1例

症例は60歳，男性．突然の右下肢痛と胸部苦悶感を主訴に前医受診．CTで下行大動脈から両側総腸骨動脈までのB型解離で腹腔動脈，上腸間膜動脈にも解離が及んでおり真腔は狭小化していたがエコー検査では明らかな血流低下は認めなかった．右総腸骨動脈は完全閉塞となっていた．緊急大腿動脈－大腿動脈バイパス術を施行し右下肢再潅流を果たした．術後abdominal anginaを発症し，下行大動脈は解離性動脈瘤を呈し拡大傾向を認めていた．そのため将来の下行大動脈瘤手術も考慮して上腸間膜動脈バイパスおよび右胃大網動脈バイパス術に加えて右腋窩動脈－大腿動脈バイパスを施行した．abdominal anginaは改善し一旦退院とした．退院約1カ月後，下行大動脈人工血管置換術を施行した．送血は大腿動脈－大腿動脈グラフトより行い頭部，腹部および下肢への送血に配慮した．術後経過は良好で術後20日目に軽快退院となった．

Hybrid total arch repair without deep hypothermic circulatory arrest for acute type A aortic dissection (R1)

To investigate the surgical outcomes of hybrid total arch repair without deep hypothermic circulatory arrest for patients with acute Stanford type A aortic dissection. Retrospective review of clinical data of patients with acute Stanford type A aortic dissection who underwent surgical repair at our institution between November 2009 and December 2011 identified 21 patients who underwent hybrid total arch repair without deep hypothermic circulatory arrest. The in-hospital and follow-up data were investigated. Postoperative serial computed tomography angiography was used to evaluate the fate of true and false lumen in arch and descending aorta. Mean follow-up was 13.8 months (range, 3 to 21 months). The 1- and 12-month survival rates (by Kaplan-Meier analysis) were 95.2% (95% confidence interval, 86.2%-100%) and 90.5% (95% confidence interval, 78.0%-100%), respectively. No endograft caudal migration occurred. One patient with type I endoleak was successfully resolved during operation. There was no late rupture or paraplegia. Hybrid total arch repair without deep hypothermic circulatory arrest offers a promising alternative to risk reduction of complications during the postoperative period and late adverse events resulting from false lumen enlargement in the arch and descending aorta.

Aortic dissection presenting as gait disturbance: a case report

Emergency medicine dogma traditionally teaches that aortic dissection presents as tearing chest pain, radiating to the back. This case report describes a 55-year-old woman presenting with a left homonymous hemianopsia and resultant gait disturbance. Initial head computed tomography demonstrated a right parietal infarct, and chest radiograph demonstrated a markedly widened mediastinum. Acute Stanford type A aortic dissection was subsequently confirmed. This report provides further evidence for atypical, painless presentations of aortic dissection. Given recent literature on the increasing prevalence of painless dissection, the disease entity should be included in the differential diagnosis for stroke, and a simple portable chest x-ray should always be obtained before administering thrombolytics.

Simplified surgical procedure of stented elephant trunk fenestration in acute Stanford type A aortic dissection

To study the technical feasibility of simplified total arch replacement via stented elephant trunk fenestration in the treatment of acute Stanford type A aortic dissection. A total of 42 consecutive patients with acute type A aortic dissection underwent total aortic arch replacement plus fenestrate stented elephant trunk implantation under hypothermic cardiopulmonary bypass and bilateral antegrade cerebral perfusion between August 2008 to February 2011. The aortic arch was accessed longitudinally. Transection of aortic arch was performed between left common carotid artery and left subclavian artery. A stented elephant trunk was inserted in descending aorta. Then the reconstruction of left subclavian artery was made by fenestration in stented elephant trunk. Finally 3-branched graft was used to complete the reconstruction of aortic arch. Operations were performed successfully. The mean cardiopulmonary bypass (CPB) time was (156 ± 42) min, mean aortic cross-clamp time (91 ± 18) min, mean circulatory arrest time (20 ± 5) min and mean antegrade cerebral perfusion (ACP) time (33 ± 7) min. No postoperative death occurred. The incidence of temporary neurological dysfunction was 4.8% (2/42). They underwent neither re-exploration for postoperative hemorrhage nor hoarseness due to recurrent nerve palsy. Left radial arterial pulses were palpable in all of them. None had sensory deficit and dyskinesia of left arm. All their angiographic findings showed complete patency of left subclavian artery. There was neither space nor blood flow around the stented elephant trunk. The false lumen of descending aorta around elephant trunk closed and obliterated in all cases. The above-mentioned technique of modified total aortic arch replacement provides a distinct operative field and may achieve simple but reliable anastomosis with less bleeding. Thus aortic arch replacement becomes easier and more effective.

Role of transthoracic echocardiography in the diagnosis of acute Stanford type A aortic dissection

stv.2012.0694 Auteur(s) : Amor Bouferrouk amorbouferrouk@yahoo.fr, Soraya Boutamine, Rachid Merghit, Aziz Trichine Hopital Benbaatouche Abdelali, service de cardiologie, BP61C, Nouvelle Ville Constantine, Algerie Tires a part : A. Bouferrouk La dissection de l’aorte est une pathologie potentiellement grave, avec une mortalite lourde atteignant 1-2 % par heure pendant les premieres 24 heures [1] : ainsi, le taux de mortalite avoisine les 50 % 48 heures apres le debut [...]

Modified Reposition of the JOTEC Prosthesis in the Frozen Elephant Trunk Procedure

We describe a procedure in which we inserted a modified JOTEC graft following a known complication in the case of a 78-year-old male patient who underwent surgery with the frozen elephant trunk technique for an acute Stanford type A aortic dissection.

ADSORB: A Prospective Randomised Study on the Efficacy of Endovascular Grafting vs. Best Medical Treatment in Uncomplicated Acute Dissection of the Descending Aorta

Many of the arterial lesions that vascular surgeons treat are on the decline, and those that currently are may soon be offered more effective drug therapy. In contrast, dissections of the aorta are increasing and are likely to represent a significant future workload and challenge for vascular surgeons. Traditionally acute Stanford type B dissections of the aorta were managed by a variety of specialists, often cardiologists. Vascular surgeons only became involved where peripheral ischaemia supervened. Dake demonstrated the feasibility of placing endovascular stentgrafts in to dissected aortas. 1 This approach appeared to offer an attractive alternative to traditional open surgical approaches for complicated aortic dissection which carried high rates of complications. 2 Consequently stent-grafts have been used increasingly in this group of patients. 3 Early efforts to reduce mortality from acute type B dissection demonstrated that effective blood pressure control in the early stages reduced mortality. Medical therapy did not necessarily prevent long-term aortic related complications. The INSTEAD Trial attempted to answer the question whether there was any benefit from placing a stent-graft in type B aortic dissection in the subacute phase (2e52 weeks). 4 There was no reduction in aortic related mortality 2 years after the initial dissection but preliminary data from INSTEAD suggests that stent-grafting might be protective in the longer term (5 years). The next question is whether there would be any additional benefit (or harm) from stenting patients within the first 2 weeks of their initial uncomplicated type B dissection? There remains scope for improvement in the 10% in-hospital mortality when treated with medical therapy. 5 It is possible that stenting might reduce mortality. However, concerns remain (due in part to a lack of data) that stenting within the first 2 weeks may be associated with significant risks even when the aortic dissection is uncomplicated. It is for these reasons that we have been following the development of the ADSORB trial keenly since its inception in 2002. Recruitmenthasbeenslow,suggestingalackofclinicalequipoiseand the change of power calculation is regrettable but seems realistic if the triallists are to complete their study. It is a pity that the trial will not have the power to demonstrate significant differences in the more robustclinicalendpoints (aortic relatedorall-causemortality). It is not clear whether the primary trial composite endpoint of a variety of aortic related events (false lumen thrombosis, aortic dilatation >5 mm, aortic rupture) at 1-year will be a clinically relevant one for patients. In the INSTEAD Trial 20% of patients managed non-operativelyachievedfalselumenthrombosis.Itisquite possible that this group of patients receiving early stent-grafting in the ADSORBtrialmightnotderiveanybenefitatall(andmaybeharmed).

Application of triple-branched stent graft for Stanford type A aortic dissection: potential risks

A new surgical technique named triple-branched stent graft was developed and reported to have excellent clinical results for Stanford type A aortic dissection. However, we found some potential risks, in our experience, of this technique. We compared this technique with total arch replacement combined with stented elephant trunk implantation in patients with acute Stanford type A dissection. Thirty-eight patients with acute Stanford type A aortic dissection underwent surgical treatment from January to November 2010. These patients were divided into two groups: patients with total arch replacement combined with stented elephant trunk implantation (Group A, n = 22) and those with ascending aorta replacement combined with open placement of triple-branched stent graft (Group B, n = 16). In-hospital mortality was not different in the two groups (9.1 and 6.25%, respectively). Cardiopulmonary bypass, aortic cross-clamp, circulation arrest, selective cerebral perfusion and low-body arrest times were shorter in Group B. Mechanical ventilation support, duration of intensive care unit (ICU) stay and hospitalization time were not different in the two groups. The incidence of postoperative stent graft-related complications was significantly higher in Group B. Actuarial survival rates and freedom from reoperation during the follow-up did not differ in the two groups. The triple-branched stent graft technique truly has some advantages in simplifying the procedure and reducing the surgical time. However, this technique has some potential risks such as postoperative stent graft shifting or kinking, which may cause occlusion, aortic disruption and malperfusion syndrome. Long-term follow-up and further multicentre clinical trials are necessary to verify their use in this setting and the design of the grafts and surgical procedure should be further refined to reduce the incidence of stent graft complications.

Acute Aortic Dissection Associated with Cystic Medial Necrosis of Unknown Etiology

A 61-year-old man without a Marfan-like phenotype was admitted to the hospital because of acute Stanford type A aortic dissection. The patient underwent surgical repair with total arch replacement. Histological examination of the excised aorta showed a connective tissue abnormality, which could have contributed to the development of aortic dissection. The cause of the connective tissue abnormality could not be determined through physical examination. Recently, however, many novel gene mutations have been found to be related to aortic diseases that do not always produce physical signs and symptoms. In this case, unknown causes of connective tissue abnormalities might be existed.

Circumferential Dissection of the Ascending Aorta ^|^ldquo;Intimo-Intimal Intussusception^|^rdquo;

We describe a rare case of acute Stanford type A dissection with "intimo-intimal intussusception." A 38-year-old male with sudden back pain and unconsciousness was admitted to the hospital. A computed tomography (CT) scan revealed the presence of an intimal flap in the aortic root and the aortic arch, absence of an intimal flap in the ascending aorta along with dilatation and occlusion of the brachiocephalic artery. Surgical treatment consisted of ascending aorta replacement under circulatory arrest. During the operation, complete circumferential detachment of the intima at the level of the sinotubular junction with an inverted flap intruding into the brachiocephalic artery was visualized. The surgery was successful with an uneventful postoperative recovery.

Modified total arch replacement plus stented elephant trunk implantation in acute type A aortic dissection: open single-branched stent graft placement

To explore the feasibility of open single-branched stent graft placement for simplified total arch replacement in acute Stanford type A aortic dissection. Between June 2008 and September 2009, 23 patients with acute Stanford type A aortic dissection underwent total arch replacement plus open single-branched stent graft placement. When core nasopharyngeal temperature dropped to 68 H, the perfusion to lower body was discontinued. Left common carotid artery was transected at its ostium and its proximal stump closed. The arch was transected at a predetermined line between innominate artery and left common carotid artery. Through a transverse incision, the main stent graft of single-branched stent graft was inserted into true lumen of descending aorta. And the side arm stent graft was positioned into left subclavian artery. The transected stump of arch was reconstructed by inner proximal stent-free Dacron tube of main graft and outer Teflon felt. Subsequently continuous anastomosis was made to a 3-branched Dacron tube graft. Open single-branched stent graft placement was technically successful in all patients. The mean cardiopulmonary bypass time, aortic cross-clamp time, lower body arrest time and selective cerebral perfusion time were (161 ± 32), (97 ± 20), (21 ± 4) and (31 ± 6) min respectively. All patients were discharged from hospital without any complication. Their computed tomographic scans at 3 months postoperatively showed that all stent grafts were fully opened and not kinked. There was neither space nor blood flow surrounding the single-branched stent graft. The false lumen of descending aorta around stent graft closed with thrombus in all cases. Open single-branched stent graft placement is a new effective technique for simplified total arch replacement in acute type A aortic dissection. With this technique, the left subclavian artery anastomosis and distal aortic anastomosis at descending aorta can be avoided.