Laparoscopic aortic reinforcement and endovascular graft placement in swine: a new external wrap

OBJECTIVE: To evaluate the feasibility, safety, and histological response of laparoscopic external aortic wrap implantation in conjunction with an endovascular stent/stent-graft placement in the infrarenal aorta in a porcine model. METHODS: Seven swine underwent laparoscopic retroperitoneal placement of a custom-made Dacron fabric wrap placed around the infrarenal aorta to create a landing zone for an endovascularly placed aortic stent/stent-graft. RESULTS: Technical success was achieved in all animals without any major complications. Follow-up ranged from 1 to 4 weeks. At necropsy, the external wraps were well incorporated into the adventitia, and the stents/stent-grafts were well incorporated into the intima. Small patches of medial necrosis of the aortic wall were observed in one animal in the stent model and in two animals in the stent-graft model. There was no transmural necrosis observed. CONCLUSIONS This adjunct technique, an external wrap around the infrarenal aorta combined with endovascular grafting, is feasible and deserves further studies into how it may be used to facilitate endovascular repair of aortic aneurysms. CLINICAL RELEVANCE: We hypothesize that our new device could provide capability of altering the proximal neck morphology of abdominal aortic aneurysm and reinforcement to the aortic wall. This, in turn, could improve eligibility for endovascular aneurysm repair and prevent or treat type I endoleak and graft migration. Future investigations will involve evaluation of the long-term effect of the external aortic wrap on the integrity of the aortic wall in an animal model and testing the clinical usefulness of this new technique.     

Different hemodynamic stress of the ascending aorta wall in patients with bicuspid and tricuspid aortic valve

It is unclear whether ascending aorta dilation in patients with bicuspid aortic valve is caused by abnormal hemodynamics or by a common developmental defect of the aortic valve and aortic wall. We performed an echocardiographic study to examine the differences in hemodynamic stress at the ascending aorta in patients with bicuspid and tricuspid aortic valve. We studied prospectively 58 consecutive patients referred for preoperative echocardiographic examination with aortic valve stenosis and either bicuspid or tricuspid valve and an ascending aortic diameter of 相似文献   

Congenital bicuspid aortic valve disease with an aneurysm of the ascending aorta in adults: vertical reduction aortoplasty with distal external synthetic wrapping

In three adult patients with diseased congenital bicuspid aortic valves and aneurysms of the ascending aorta, we performed aortic valve replacements, and combined a proximal and middle vertical reduction aortoplasty with a distal external synthetic wrapping. During a mean follow-up of 23.3 months there is no evidence of compression of the innominate artery by the distal external synthetic wrap, and no redilatation of the ascending aorta.     

Redo operations for recurrent aneurysmal disease of the ascending aorta and transverse aortic arch

Sixty-seven operations were performed in 59 patients for aneurysmal disease occurring after previous operations involving the ascending aorta and transverse aortic arch. The initial aortic pathological condition included the following: fusiform aneurysm due to medial degenerative disease in 34 patients, 12 of whom had Marfan's syndrome; aortic dissection in a previously undilated aorta in 23; and aneurysm persisting or occurring after brachiocephalic bypass in 2. One of the latter had an aneurysm because of aortitis. Various operations initially performed did not completely treat the disease, and certain complications occurred spontaneously, including infection and dissection. The residual pathological condition led to the development of aortic insufficiency, aortic dissection, coronary artery insufficiency, and progressive aneurysmal dilatation. These complications were treated by composite valve graft replacement of the aortic valve and ascending aorta or the transverse aortic arch or both, simple aortic valve replacement, graft replacement of the ascending aorta or arch or both, and suture of false aneurysm with viable tissue wrap. Twenty patients (34%) had an aneurysm of the distal aorta. The entire aorta was replaced in 3, thoracoabdominal segments in 9, and the abdominal aorta in 1. Of the 59 patients, 49 (83%) were early survivors and 40 (68%) were alive on January 1, 1985. Principles of therapy that may have prevented the complications leading to reoperation include aneurysm replacement at the time of aortic valve replacement and coronary artery bypass; total replacement of the ascending aorta and aortic valve in patients with Marfan's syndrome; the same procedure or aortic valve replacement and separate graft replacement in patients with non-Marfan's medial degenerative disease; ascending aortic replacement in all patients with dissection combined with valve resuspension, aortic valve replacement, or composite valve graft depending on the involvement of the aortic sinuses and the presence of aortic insufficiency.     

Morphometric analysis of aortic media in patients with bicuspid and tricuspid aortic valve

BACKGROUND: Patients with bicuspid aortic valves tend to develop dilatation of the ascending aorta. The aim of this study was to analyze whether or not there is any histologic difference in the aortic media of patients with a bicuspid aortic valve or a tricuspid aortic valve. METHODS: A morphometric analysis of the wall of the ascending aorta was performed in 107 patients with bicuspid aortic valves undergoing aortic valve operations. The thickness of the elastic lamellae of the aortic media and the distances between the elastic lamellae were measured with the use of an image analysis system. The histologic specimens of the ascending aorta from 61 surgical patients with tricuspid aortic valve disease served as a control. RESULTS: The patients with bicuspid aortic valves had thinner elastic lamellae of the aortic media (2.71 +/- 0.23 microm) of the ascending aortic wall than the patients with tricuspid aortic valve disease (2.83 +/- 0.23 microm) (p = 0.006). The patients with bicuspid aortic valves also had greater distances between the elastic lamellae (27.21 +/- 8.69 microm) of the ascending aortic wall in comparison with the patients with tricuspid aortic valve disease (24.34 +/- 5.32 microm) (p = 0.033). There was no difference in the total thickness of the aortic media between the groups (p = 0.62). CONCLUSIONS: Patients with a bicuspid aortic valve had thinner elastic lamellae of the aortic media and greater distances between the elastic lamellae than patients with a tricuspid aortic valve.     

Immunohistochemical Abnormalities of Fibrillin in Cardiovascular Tissues in Marfan’s Syndrome

Background. Molecular defects in the glycoprotein fibrillin are believed to be responsible for impaired structural integrity of cardiovascular, skeletal, and ocular tissues in Marfan’s syndrome (MFS). Traditionally, excellent results have been achieved with the Bentall composite graft repair of aneurysms of the ascending aorta in MFS. However, because of the potential complications associated with prosthetic valves, there is growing interest in techniques that preserve the native aortic valve.Methods. Between May 1994 and February 1995, 15 patients with a history of concomitant or remote aortic root aneurysms or dissection underwent operation for valvular heart disease. Specimens of aortic valve, ascending aortic wall, and mitral valve were obtained specifically to observe differences in fibrillin content and architecture between patients with (n = 9) and without (n = 6) MFS. In addition, control specimens of aortic valve, aortic wall, and mitral valve were obtained from 4 patients with isolated valvular or coronary artery disease but no evidence of connective tissue disorders or other aortic pathologic conditions. Fibrillin immunostaining using indirect immunofluorescence was used. Specimens were coded and graded by a blinded observer to determine quantity, homogeneity, and fragmentation of fibrillin.Results. Observed fibrillin abnormalities in MFS and control patients were limited to the midportion (elastin-associated microfibrils) of the aortic valve, aortic wall, and mitral valve tissues. Fibrillin abnormalities of aortic valve, aortic wall, and mitral valve tissues were seen in all patients with MFS and were most severe in those older than 20 years. Similar fibrillin abnormalities of aortic valve and aortic wall specimens were observed in control patients more than 60 years old.Conclusions. Even in the setting of a normal-appearing aortic valve, the current rationale for widespread use of valve-sparing repairs of aortic root aneurysms in patients with MFS and patients older than 60 years should be carefully reexamined in light of these findings.(Ann Thorac Surg 1997;63:1012–17)     

Sixteen-year experience with aortic root replacement. Results of 172 operations.

During a 16-year interval ending in October 1990, 168 patients underwent 172 aortic root replacements. Thirty patients (18%) had Marfan syndrome. Annuloaortic ectasia (81 patients) and aortic dissection (63 patients) were the principal indications for operation. Twenty-seven patients (16%) had previous operations on the ascending aorta or aortic valve. The hospital mortality rate was 5% and the duration of cardiopulmonary bypass was the only significant independent predictor of early death (p = 0.017). Major modifications in technique were made in 1981, when the inclusion/wrap technique employing a composite graft (used in the first 105 procedures) was abandoned in favor of an open technique (used in 51 procedures), and in 1988, when aortic allografts and pulmonary autografts were introduced for selected conditions (reoperations, dissection, endocarditis, isolated aortic valve disease) in 16 patients. The mean duration of follow-up was 81 months. Forty-six patients were followed for more than 10 years. The actuarial survival rate was 61% at 7 years and 48% at 12 years. No significant difference in survival rate was observed between the patients with annuloaortic ectasia and aortic dissection, or between the inclusion/wrap and open techniques. However the frequency of pseudoaneurysm formation at suture lines and the frequency of reoperations on the ascending aorta and aortic valve were less with the open technique. The actuarial freedom from thromboembolism for the 152 patients with prosthetic valves was 82% at 12 years. One early and one late death occurred among the 16 patients with allograft or autograft root replacement. Anticoagulant therapy was not used in these patients and no thromboembolic episodes occurred in the follow-up period (mean, 7 months). The satisfactory results observed with extended follow-up support the continued use of the composite graft technique as the preferred method of treatment for patients with annuloaortic ectasia, persistent aneurysms of the sinuses of Valsalva following previous operations, and for patients with ascending aortic dissection who require aortic valve replacement. The availability of aortic root allografts and the perfection of techniques for safe implantation of the autologous pulmonary root into the aortic position have broadened the indications for aortic root replacement.     

Aortic shear stress in patients with bicuspid aortic valve with stenosis and insufficiency

Objectives

Bicuspid aortic valve, characterized by valve malformation and risk for aortopathy, displays profound alteration in systolic aortic outflow and wall shear stress distribution. The present study performed 4-dimensional flow magnetic resonance imaging in patients with bicuspid aortic valve with right-left cusp fusion, focusing on the impact of valve function on hemodynamic status within the ascending aorta.

Challenging corrective redo surgery in a patient presenting with severe aortic redilatation following an aortic root reduction aortoplasty with concomitant external wrapping

We report a case of severe long‐term failure of an aortic root reduction aortoplasty with external wrapping. The patient presented 13 years after the initial surgery with a large redilatation of the aortic root and major atrophy of the native aortic root wall inside the external wrap. This subsequently necessitated challenging corrective redo surgery with a Bentall procedure. This case highlights the potential long‐term risk of redilatation posed by using reduction aortoplasty with concomitant aortic external wrapping as a technique to treat largely aneurysmal aortic roots.     

A case of atypical aortic coarctation with mitral and aortic regurgitation and ascending aortic dilatation

A 67-year-old female presented with dyspnea on exertion as a chief complaint. Diagnosed as having severe mitral regurgitation, aortic regurgitation, dilatation of the ascending aorta and atypical coarctation due to aortitis syndrome, she underwent mitral valve replacement, aortic valve replacement, ascending aorta and hemiarch replacement and ascending aorta-abdominal aorta extraanatomical bypass in one stage. Pathologically, typical findings of aortitis syndrome were not observed in the wall of the ascending aorta and aortic valve, but cystic medionecrosis was noted in the wall of the ascending aorta. Follow-up observations are needed for the remaining aortic wall.     

Modification of the Bentall operation using the proximal double sewing technique without excision of leaflets

We present a report on reinforcement of the proximal anastomosis during the Bentall operation. The aortic wall was excised with a 5-mm remnant, and aortic valve leaflets were preserved. Interrupted horizontal mattress sutures (2-0 Polyestel) reinforced with pledgets were placed. The composite graft was placed at the intraannular position inside of the preserved leaflets. The aortic valve leaflets were then pasted to the sewing cuff with fibrin glue. A running suture with 4-0 monofilament was placed between the remnant of the aortic wall and the peripheral side of the sewing cuff wrapped with native aortic valve leaflets.     

Calcification resistance with aluminum-ethanol treated porcine aortic valve bioprostheses in juvenile sheep

BACKGROUND: Calcification of glutaraldehyde fixed bioprosthetic heart valve replacements frequently leads to the clinical failure of these devices. Previous research by our group has demonstrated that ethanol pretreatment prevents bioprosthetic cusp calcification, but not aortic wall calcification. We have also shown that aluminum chloride pretreatment prevents bioprosthetic aortic wall calcification. This study evaluated the combined use of aluminum and ethanol to prevent both bioprosthetic porcine aortic valve cusp and aortic wall calcification in rat subcutaneous implants, and the juvenile sheep mitral valve replacement model. METHODS: Glutaraldehyde fixed cusps and aortic wall samples were pretreated sequentially first with aluminum chloride (AlCl3) followed by ethanol pretreatment. These samples were then implanted subdermally in rats with explants at 21 and 63 days. Stent mounted bioprostheses were prepared either sequentially as previously described or differentially with AlCl3 exposure restricted to the aortic wall followed by ethanol pretreatment. Mitral valve replacements were carried out in juvenile sheep with elective retrievals at 90 days. RESULTS: Rat subdermal explants demonstrated that sequential exposure to AlCl3 and ethanol completely inhibited bioprosthetic cusp and aortic wall calcification compared with controls. However the sheep results were markedly different. The differential sheep explant group exhibited very low levels of cusp and wall calcium. The glutaraldehyde group exhibited little cusp calcification, but prominent aortic wall calcification. All sheep in the two groups previously described lived to term without evidence of valvular dysfunction. In contrast, animals in the sequential group exhibited increased levels of cusp calcification. None of the animals in this group survived to term. Pathologic analysis of the valves in the sequential group determined that valve failure was caused by calcification and stenosis of the aortic cusps. CONCLUSIONS: The results clearly demonstrate that a combination of aluminum and ethanol reduced aortic wall calcification and prevented cuspal calcification. Furthermore, this study demonstrates that exclusion of aluminum from the cusp eliminated the cuspal calcification seen when aluminum and ethanol treatments were administered in a sequential manner.     

Aortic dissection late after aortic valve replacement

We experienced 3 cases of an aortic dissection occurring late after an aortic valve replacement, and sucessfully treated by an aortic root replacement. An aortic dissection involving the ascending aorta can develop late after an aortic valve replacement, and such an occurrence is associated with a high mortality and morbidity. The development of effective surgical strategies at the initial aortic valve surgery, strict control of blood pressure after aortic valve replacement, serial evaluations of aortic size, and the prophylactic replacement of the ascending aorta for patients with aortic dilatation after aortic valve replacement, all play clinically important roles in preventing an aortic dissection after aortic valve replacement. When an aortic dissection occurs in patients with a previous aortic valve replacement, an aortic root replacement should be performed in order to avoid leaving the fragile diseased aortic wall including the sinus of Valsalva.     

Resection and end-to-end anastomosis for ascending aortic aneurysms associated with a bicuspid valve: case reports

Ascending aortic aneurysms associated with a bicuspid valve are generally treated by replacement with a tubular graft because the aortic wall is claimed to be genetically pathological. We describe 9 cases in which patients with an ascending aortic aneurysm and an associated diseased bicuspid valve underwent aneurysmal resection and end-to-end anastomosis. This technique permitted us to remove the entire aneurysmal wall, avoiding graft interposition.     

Cause of degenerative disease of the trileaflet aortic valve: review of subject and presentation of a new theory

Risk factors for both atherosclerotic aortic wall disease and degenerative disease of the trileaflet aortic valve are very similar if not identical. This correlation grows even stronger as the person advances in years. Because of this, it is the prevailing view that sclerosis of the trileaflet aortic valve, unless previously affected by septic or rheumatic endocarditis, is a disease similar in origin to sclerosis of the aortic wall, ie, degenerative aortic valve disease is arteriosclerosis of the aortic valve. Our studies challenge these views. The aortic valve is a functional assembly composed of the three cusps, corresponding sinuses, and the sino-tubular junction, characterized not only by morphologic features but also by its functional properties, which together create an environment that is optimal for distribution of diastolic pressure load and assures proper and timely valve opening and closure. Our more recent experiments also demonstrate that loss of aortic wall compliance at the level of the sinuses leads to significant stress-overload on the aortic leaflets and it is likely to start a chain of events, which begins with minor changes in their microstructure, then continues in more evident sclerosis, and finally ends in gross distortion or calcification of the cusps. The loss of the "pull-and-release" process may also play a part in disintegration of bioprosthetic valves and in degeneration of native aortic valves encased in noncompliant prostheses.     

Congenital aortic valve anomaly. Aortic regurgitation with left coronary artery isolation.

A case is reported of aortic regurgitation resulting from a congenitally abnormal aortic valve. The left coronary cusp of the valve was small and adhered to the aortic wall, so that there was insufficient valve tissue to maintain diastolic valve competence. In addition, this rudimentary cusp completely occluded the left coronary ostium. The patient was treated successfully by valve replacement.     

Surgical technique for aortic regurgitation attributable to Behcet's disease: modified aortic valve replacement with reinforcement of the aortic wall

Aortic regurgitation is a severe cardiovascular complication of Behcet's disease, resulting in high mortality rates within the Asian population. Standard surgical interventions have resulted in poor results in the long term. We herein report on a modified aortic valve replacement technique coupled with reinforcement of the aortic wall. During this procedure, Teflon felts and continuous mattress stitches were used to reinforce the aortic wall in order to prevent prosthetic valve detachment and formation of an aortic pseudoaneurysm. Postoperative examinations revealed that this procedure had satisfactory mid-term results.     

External aortic wrap for repair of type 1 endoleak

INTRODUCTION

Type 1 endoleak is a rare complication after endovascular abdominal aortic aneurysm repair (EVAR) with a reported frequency up to 2.88%. It is a major risk factor for aneurysmal enlargement and rupture.

PRESENTATION OF CASE

We present a case of a 68 year old gentleman who was found to have a proximal type 1 endoleak with loss of graft wall apposition on routine surveillance imaging post-EVAR. An initial attempt at endovascular repair was unsuccessful. Given the patient''s multiple medical co-morbidities, which precluded the possibility of conventional graft explantation and open repair, we performed a novel surgical technique which did not require aortic cross-clamping. A double-layered Dacron wrap was secured around the infra-renal aorta with Prolene sutures, effectively hoisting the posterior bulge to allow wall to graft apposition and excluding the endoleak. Post-operative CT angiogram showed resolution of the endoleak and a stable sac size.

DISCUSSION

Several anatomical factors need to be considered when this technique is proposed including aortic neck angulation, position of lumbar arteries and peri-aortic venous anatomy. While an external wrap technique has been investigated sporadically for vascular aneurysms, to our knowledge there is only one similar case in the literature.

CONCLUSION

Provided certain anatomical features are present, an external aortic wrap is a useful and successful option to manage type 1 endoleak in high-risk patients who are unsuitable for aortic clamping.     

Size reduction ascending aortoplasty: is it dead or alive?

OBJECTIVE: Reduction ascending aortoplasty is a controversial procedure. Some believe that it can be appropriately applied when the anatomic features are favorable. Others suggest that it should be restricted to those patients who are at unacceptably high risk for more radical procedures, and there are also those who believe that reduction ascending aortoplasty should not be applied at all. The purpose of the article is to draw conclusions on the applicability of reduction ascending aortoplasty in modern cardiovascular surgery. METHODS: The issue was examined in the mirror of the authors' own experiences, by review and scrutiny of the literature available on the subject, and by conducting an extensive survey of the profession. RESULTS: We found that given proper indications (ie, poststenotic dilatations of <6 cm in diameter, absence of cystic medial necrosis, and a technique that decreases aortic diameter to <3.5 cm), nonreinforced reduction ascending aortoplasty performed concomitantly with aortic valve replacement appears to be a simple and safe procedure, with low morbidity and mortality and rare late complications. External reinforcement might extend the scope of indication for reduction ascending aortoplasty to ascending aortic aneurysms associated with aortic regurgitation and to those with primary structural aortic wall disease with comparable results. Experience also has shown that late complications might be further reduced by means of proper proximal anchoring and extending the wrap past the origin of the innominate artery. CONCLUSIONS: We conclude that reduction ascending aortoplasty is certainly alive. Although it does not appear to be an extremely popular operation, about half of the surgeons who responded believe it to be justified. Regardless of which modality is used, lifetime monitoring of ascending aortic size is essential and so advised. Because of recent sporadic reports of "under-the-wrap" aortic wall atrophy and rupture, the issue of reinforcement of reduction ascending aortoplasty requires continued re-evaluation.     

A technique of aortic annulus enlargement with a Freestyle stentless bioprosthesis

We describe our surgical technique to manage a small aortic annulus during aortic valve replacement. Starting with the posterior annular enlargement incision described by Manouguian, a stentless porcine aortic root, with excision of the left and right porcine coronary segments and conservation of the mural wall (Freestyle MS design, Medtronic, Minneapolis, MN ), was used. The Freestyle bioprosthesis enlarges the aortic annulus using a direct suture of the valve on the enlarged annulus, and the aorta is closed by a direct suture of the mural wall of the bioprosthesis. Therefore, the aortic annulus enlargement is made only using the aortic bioprosthesis, without other material.