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1.
OBJECTIVE: The aim of the present study was to define a method to pre-determine the correct size of neo-sinuses of Valsalva in the reimplantation type of valve-sparing aortic operation. METHODS: The objective was achieved in three steps: (1) evaluation in the healthy population, of the normal size of sinuses of Valsalva expressed as the area surrounding fully opened aortic cusps, the so-called beyond leaflets area; (2) elaboration of a normogram by which, given a known annular diameter, it is possible to select the appropriate graft size to obtain a normal beyond leaflets area; (3) validation of the normogram by comparing, in a population of 20 patients undergoing a valve-sparing procedure, the predicted and observed beyond leaflets area. RESULTS: The following values for beyond leaflets area were observed: mean normal 320.6+/-120.6mm(2), mean predicted 355+/-63.2mm(2), mean observed 364.7+/-72.8mm(2).No significant differences were obtained for predicted versus observed values. Regression analysis showed a linear distribution with an r value of 0.95. CONCLUSIONS: We proposed a simplified approach for sizing of the neo-aortic root in the reimplantation type of valve-sparing aortic operation focussed on the size of sinuses of Valsalva. Our normogram showed to be reliable in anticipating beyond leaflets area. It can be helpful in avoiding the selection of an undersized or excessively oversized graft.  相似文献   

2.
Aortic incompetence in Marfan's syndrome results from distortion or dilatation of the sinuses of Valsalva, annuloaortic ectasia or a combination of these problems. Valve leaflets in these patients are macroscopically normal in spite of aortic insufficiency. Replacement of the ascending aorta, root and aortic valve with a composite graft was, for a long time, the treatment of choice for Marfan patients. Valve-preserving procedures (remodeling or reimplantation) provide the advantages of avoiding the shortcomings of standard surgical techniques, and maintaining the functional integrity of the left ventricular (LV) outflow tract, aortic root and ascending aorta. We developed a modified valve-sparing reimplantation technique for avoiding leaflet damage. This was achieved by leaving a 'cushion' of aortic wall (8--10 mm) that, sewn on the Dacron graft, works as a 'damper' and prevents leaflets injury during the systolic opening of the valve. For final judgment of this operative method long-term results are necessary.  相似文献   

3.
Aortic valve-sparing operations have provided very good clinical outcomes. However, the absence of the sinuses of Valsalva might limit valve durability. The Gelweave Valsalva prosthesis, which presents pre-fashioned neo-sinuses, has been designed in order to avoid early leaflets deterioration. We report our results in 63 patients who underwent valve-sparing operations (reimplantation technique) using the Gelweave Valsalva graft. The main indication was ascending aorta aneurysm or annuloaortic ectasia, with or without aortic insufficiency. The operation was performed also in cases of Marfan syndrome, Bicuspid Aortic Valve (BAV), and acute Type A dissection. In-hospital mortality was of 4.7%, and two thirds were acute Type A dissection patients (P=0.01). There were no late deaths. Three years freedom from grade 3-4 AI and freedom from late aortic valve replacement were 91.7+/-4.3% and 93.8+/-5.1%, respectively. Aortic valve-sparing operations show good results in patients electively operated for aortic root ectasia. Aortic cusps repair may lead to late failure. Even if the Gelweave Valsalva prosthesis is easy to implant and it also reproduces pseudosinuses, a long-term follow up is necessary to determine if this graft may reduce leaflets deterioration.  相似文献   

4.
We have used in‐body tissue architecture technology to develop an autologous valved conduit with intact sinuses of Valsalva (biovalve). In this study, we fabricated three different forms of biovalves and evaluated their function in vitro using a mock circulation model to determine the optimal biovalve form for aortic valve replacement. A cylindrical mold for biovalve organization was placed in a dorsal subcutaneous pouch of a goat, and the implant that was encapsulated with connective tissue was extracted 2 months later. The cylindrical mold was removed to obtain the biovalve (16 mm inside diameter) that consisted of pure connective tissue. The biovalve was connected to a pulsatile mock circulation system in the aortic valve position. The function of the three biovalves (biovalve A: normal leaflets with the sinuses of Valsalva; biovalve B: extended leaflets with the sinuses of Valsalva; biovalve C: extended leaflets without the sinuses of Valsalva) was examined under pulsatile flow conditions using saline. In addition, the mock circuit was operated continuously for 40 days to evaluate the durability of biovalve C. The regurgitation rate (expressed as a percent of the mean aortic flow rate during diastole) was 46% for biovalve A but only 3% for biovalves B and C. The durability test demonstrated that even after biovalve C pulsated more than four million times (heart rate, 70 bpm; mean flow rate, 5.0 L/min; mean aortic pressure, 92 mm Hg), stable continuous operation was possible without excessive reduction of the flow rate or bursting. The developed biovalve demonstrated good function and durability in this initial in vitro study.  相似文献   

5.
The absence of sinuses of Valsalva is postulated to perturb coronary flow patterns and to create abnormal leaflet stresses, which theoretically may limit the long-term durability of valve-sparing aortic root replacement with the original Tirone David-I reimplantation technique with a cylindrical tube graft. David developed the “T. David-V” procedure in 2001; it creates large billowing Dacron pseudosinuses while retaining the reimplantation concept. To illustrate a simple modification of the T. David-V technique, we describe a patient with Marfan's syndrome who underwent valve-sparing aortic root replacement with 1 large and 1 small graft to create pseudosinuses in the Dacron graft, to facilitate suturing the valve inside the graft, and to make the distal graft-to-aorta anastomosis a better size match.  相似文献   

6.
OBJECTIVE: Sparing the aortic valve has become a surgical option for patients who require repair of aortic root ectasia and have normal valve leaflets. Surgical approaches to valve sparing differ with regard to preservation of the native sinuses of Valsalva. The role of the sinuses and the importance of maintaining them remain controversial. METHODS: By using a time-resolved, 3-dimensional, phase-contrast magnetic resonance imaging technique, aortic root and aortic blood velocity data were acquired from 2 patients with Marfan syndrome 6 months after aortic valve-sparing surgery with straight Dacron grafts and contrasted with data from 6 normal volunteers. RESULTS: In normal aortas vortical blood flow became apparent in the individual sinuses after peak systole. The vortices filled the available space behind the valve leaflets and persisted until diastole, expanding and moving inward during aortic valve closure. In contrast, no vortices were observed in the postoperative patients with Marfan syndrome with negligible sinuses. CONCLUSIONS: Changes in supravalvular flow accompany loss of sinus architecture. Whether the presence, size, and velocity of supravalvular vortices affects the function or durability of the preserved aortic valve remains to be studied.  相似文献   

7.
The aim of this study is to evaluate distensibility of the aortic root and function of the aortic cusp after aortic root replacement using valve sparing procedure. Between October 1999 and August 2006, valve sparing aortic root replacements were performed in 39 patients who had annuloaortic ectasia (AAE) and aortic valve regurgitation. Reimplantation type of valve-sparing procedure was performed with a tube graft (n=12) or a Valsalva graft (n=27). Echocardiographic studies were performed six months after the operation comparing Valsalva graft (Group V, n=15), tube graft (Group T, n=5), and normal control (Group C, n=5). Percent changes in radius (PCR) of the aortic root were measured as indices of distensibility. Rapid valve opening velocity (RVOV/HR (mm/s/min)) and rapid valve closing velocity (RVCV/HR (mm/s/min)) of the aortic cusp were analyzed in each group. Root distensibility of sinus in Group T (1.9+/-1.1) was significantly smaller than Group C (7.2+/-1.8) (P=0.003). RVOV/HR in Group T was highest among the three groups (T: 48.2+/-6.2, V: 36.2+/-11.9, C: 33.7+/-9.6). RVCV/HR showed no difference among the three groups (T: 26.1+/-6.7, V: 40.7+/-16.6, C: 28.4+/-16.3). In conclusion, sinus distensibility of the Valsalva graft was well preserved and valve-opening characteristics with the Valsalva graft were identical to normal.  相似文献   

8.
The aortic root has a unique 3-dimensional configuration and the distinctive function of supporting the aortic valve and blood vessels. The sinuses of Valsalva are crucial to create appropriate eddy currents that are important in initiating and coordinating aortic valve closure and promoting coronary artery blood flow. Most aneurysms in the aortic root are associated with degenerative changes in the elastic media rather than atherosclerosis. Valve-sparing root repair has become widely accepted, although the Bentall procedure remains the gold standard. Because reimplantation using the Valsalva graft allows root geometry to be retained and theoretically and practically prevents recurrent aortic valve regurgitation, it is considered the most reliable and preferred technique among various valve-sparing aortic root repair procedures.  相似文献   

9.
BACKGROUND: The durability of aortic valve-sparing procedures is negatively affected by increased leaflet stress in the absence of normally shaped sinuses of Valsalva. We compared valve motion after remodeling procedures using a standard conduit and a specifically designed aortic root conduit. METHODS: Echocardiographic studies of the aortic valve dynamics were performed in 14 patients after remodeling of the aortic root (7 standard conduits, group A; 7 new conduits, group B) and in 7 controls (group C). Opening and closing leaflet velocities and percent of slow closing leaflet displacement were measured. Root distensibility and the pressure strain of the elastic modulus were measured at all root levels. RESULTS: Root distensibility and the pressure strain of the elastic modulus were different in group A and B only at the sinuses (p < 0.001). Opening and closing leaflet velocities were not different among groups. Slow closing leaflet displacement was markedly more evident in group B patients (24.2%+/-1.9% versus 2.5%+/-1.9% in group A, p < 0.001) and similar to controls (22.1%+/-7.9%). CONCLUSIONS: The new conduit guarantees dynamic features of the aortic valve leaflets superior to those obtained with standard conduits and more similar to normal subjects.  相似文献   

10.
Sinotubular junction reconstruction in reimplantation type of valve-sparing aortic procedure can present some problem when a Valsalva graft is used. Since in the Valsalva graft the sinotubular junction height is predetermined, correct matching with native commissures height can be difficult. We propose a method by which it is possible to create a new sinotubular junction in Valsalva graft without altering its original configuration.  相似文献   

11.
Typically, a sinus of Valsalva aneurysm with severe aortic incompetence is repaired with patch closure and aortic valve replacement. Here, we describe a very rare case of a giant nonruptured right Valsalva aneurysm, combined with severe aortic incompetence, treated with a valve-sparing aortic root replacement. During surgery we noted that the lengths of the free margin of the cusps and annuli were not uniform. As a result, we placed the first layer of sutures for the Valsalva graft in the same ratio as the annuli. It is difficult to preserve the geometry of the aortic annulus and position the commissures in the graft. One surgical tip for valve-sparing aortic root replacement for a sinus of Valsalva aneurysm with severe aortic incompetence is to suture the commissures inside the graft in the same ratio as the length of the cusp free margins.  相似文献   

12.
BACKGROUND: The reimplantation type of valve-sparing procedure does not allow proper reconstruction of the sinuses of Valsalva. We assessed the valve motion after a reimplantation type (David I) of valve-sparing procedure using a new Dacron conduit that incorporates sinuses of Valsalva. METHODS: Nine consecutive patients undergoing an aortic valve-sparing procedure using the new conduit were studied using two-dimensional transesophageal echocardiography shortly (2 +/- 1 months) after operation to determine root distensibility, expressed as percent change in radius and as pressure strain of the elastic modulus. Next, monodimensional view was used to assess valve motion in its various phases (rapid valve opening velocity, slow closing leaflet displacement, rapid valve closing velocity, maximal leaflet displacement, and leaflet displacement before valve closure). Seven healthy individuals served as control subjects. RESULTS: Root distensibility was reduced at the level of the annulus and sinotubular junction but was similar to control subjects at the level of the sinuses (percent change in radius, 4.1% +/- 0.8% versus 4.5% +/- 1.2%; pressure strain of the elastic modulus, 1,286 +/- 674 g/cm2 versus 1,195 +/- 628 g/cm2). Rapid valve opening (69 +/- 34.4 cm/s versus 51 +/- 11.9 cm/s) and closing (47.6 +/- 16 cm/s versus 36.4 +/- 9 cm/s) velocity as well as slow closing leaflet displacement (24% +/- 4.7% versus 22.1% +/- 7.9%), maximal leaflet displacement (20.1 +/- 4 mm versus 22.7 +/- 1.9 mm), and leaflet displacement before valve closure (15.2 +/- 3 mm versus 17.6 +/- 0.8 mm) were similar to control subjects. CONCLUSIONS: The new aortic root conduit used in a reimplantation type of valve-sparing procedure allows the anatomic reconstruction of the aortic root with leaflet motion similar to that of normal subjects.  相似文献   

13.
A 35 year-old male with Marfan's syndrome was referred with a fortuitous echographic finding of an abdominal aorta flap. Transthoracic echocardiography showed moderate aortic regurgitation and an aneurysm in the sinus of Valsalva. Computed tomography demonstrated an aneurysm in the sinus of Valsalva 60 mm in size and a DeBakey type IIIb dissection extending from the left subclavian artery to the right common iliac artery. An aortic valve-sparing operation (reimplantation), total aortic arch replacement and the elephant trunk method were used in this patient. An aortic valve-sparing operation is preferable because the patient is young, and has no need for anticoagulant therapy after surgery. The extent of the aortic reconstruction, including the intact aortic arch, was appropriate to prohibit future dilatation of the aortic arch and retrograde dissection from a DeBakey type IIIb dissection. (Jpn J Thorac Cardiovasc Surg 2005;53: 657–660)  相似文献   

14.
BACKGROUND: High reoperation rates after supracommissural tube graft replacement for acute type A dissection due to sinus of Valsalva dilation have been reported. Valve-sparing operations focusing on the replacement of the sinus of Valsalva are an appealing alternative. The applicability of these techniques in acute type A dissection remains debatable and results are limited. METHODS: From 1992 to 1998, 20 patients with acute type A dissection received a valve-sparing aortic root replacement. Two different types of aortic valve-sparing operations were performed: the remodeling technique in 11 patients and the reimplantation technique in 9 patients. Patients were followed for 26 +/- 18 months. Echocardiographic studies were performed every 6 months. RESULTS: There were 2 early postoperative deaths and no late death, no reoperation, and no thromboembolic events. The latest echocardiographic studies of the 18 survivors showed a competent valve in 12 and a trivial aortic valve insufficiency in 6 patients. The mean aortic valve pressure gradient was 4.3 +/- 1.3 mm Hg. CONCLUSIONS: These midterm results support the surgical strategy of valve-sparing aortic root replacement in patients with acute type A dissection.  相似文献   

15.
A 55-year-old female noticed worsening exertional dyspnoea for two years. She was born with cleft palate and profound deafness. Significant physical findings included dysmorphism with micrognathia and acrocephaly and congenital deafness. Transthoracic echocardiogram revealed aneurysms involving the right and the non-coronary sinuses of Valsalva. Despite that, the native aortic valve retained preserved geometry. Computed tomography (CT)-scan demonstrated multiple aneurysms arising from all three sinuses of Valsalva. This displaced the right ventricle (RV) caudally and indented the RV outflow tract. A valve-sparing root reimplantation was planned. However, intraoperatively the root aneurysms were found to be very extensive such that no healthy tissue remained along the insertion lines of the aortic valve leaflets. The aortic annulus was not dilated (2 cm) and the left ventricular outlow tract was not involved in the disease process. Consequently, despite the presence of macroscopically normal leaflets and relatively undisturbed annular geometry, we were unable to reimplant the native aortic valve and proceeded to a modified Bentall procedure. Histologically, significant medial degeneration with loss of elastin and muscle was identified in the aortic sinus wall. Similar changes were also found affecting the native leaflets coupled with increased fibrous thickening.  相似文献   

16.
A 35 year-old male with Marfan's syndrome was referred with a fortuitous echographic finding of an abdominal aorta flap. Transthoracic echocardiography showed moderate aortic regurgitation and an aneurysm in the sinus of Valsalva. Computed tomography demonstrated an aneurysm in the sinus of Valsalva 60 mm in size and a DeBakey type IIIb dissection extending from the left subclavian artery to the right common iliac artery. An aortic valve-sparing operation (reimplantation), total aortic arch replacement and the elephant trunk method were used in this patient. An aortic valve-sparing operation is preferable because the patient is young, and has no need for anticoagulant therapy after surgery. The extent of the aortic reconstruction, including the intact aortic arch, was appropriate to prohibit future dilatation of the aortic arch and retrograde dissection from a DeBakey type IIIb dissection.  相似文献   

17.
OBJECTIVE: Endovascular repair of abdominal aortic aneurysm (AAA) is complicated by the potential for stent graft migration over time. Factors including the type of fixation, initial proximal fixation length, and dilation and elongation of the infrarenal aortic neck may contribute to device migration. We sought to determine when device migration is a real phenomenon with actual device movement that compromises aneurysm exclusion. METHODS: Computed tomographic (CT) scans and computer reconstructions of all patients undergoing endovascular AAA repair with a passive fixation device at our institution from June 1996 to October 2004 were retrospectively reviewed. The distance from the distal renal artery to the proximal end of the stent graft at the time of initial deployment was determined for each patient. Migration was defined as a distance increase greater than 5 mm in the follow-up period; proximal fixation length, aortic neck enlargement and elongation, and neck angle were then measured. Data were further analyzed with respect to AAA growth, development of endoleak, AAA rupture, and the need for reintervention. RESULTS: A total of 308 patients with endovascular AAA repairs using a passive fixation device had complete postoperative imaging data sets; 48 patients (15.6%) with stent graft migration of 5 mm or more were identified, and 25 (8.1%) of these had a migration of 10 mm or more. Seventeen (35.4%) of 48 migration patients had a total loss of the proximal seal zone (loss patients); their average migration distance was 17.7 +/- 12.0 mm, with a mean neck shortening of 13.6 +/- 14.2 mm, and the average proximal fixation length loss was 14.0 +/- 7.6 mm. Those 31 patients with an intact proximal seal zone (nonloss patients) showed an average migration of 9.4 +/- 3.7 mm, with a mean neck lengthening of 9.6 +/- 8.4 mm and an average proximal fixation length change of 0.7 +/- 8.0 mm. Univariate analysis demonstrated significant differences between the loss and nonloss patients in follow-up duration (65.9 +/- 20.4 months vs 45.9 +/- 26.4 months; P = .01), neck dilatation at the distal renal artery (4.6 +/- 4.5 mm vs 1.8 +/- 1.9 mm; P = .026), stent graft migration distance (17.7 +/- 12.0 mm vs 9.4 +/- 3.7 mm; P = .001), change in aortic neck length (-13.6 +/- 14.2 mm vs 9.6 +/- 8.4 mm; P < .0001), change in proximal fixation length (-14.0 +/- 7.6 mm vs 0.7 +/- 8.0 mm; P < .0001), change in AAA size (1.8 +/- 7.1 mm vs -3.6 +/- 9.7 mm; P = .033), and use of a stiff body stent graft (47.1% vs 19.4%; P = .043). However, only change in aortic neck length was statistically significant on multivariate analysis (odds ratio, 0.75; 95% confidence interval, 0.591-0.961; P = .022). There were no differences between the loss and nonloss patients in time to migration discovery, initial AAA size, initial aortic neck diameter or length, initial device oversizing, initial neck angle, neck angle increase, type II endoleak, or AAA rupture. Eight of the 17 loss patients have been treated with proximal aortic cuffs; the remainder have refused reintervention, died of unrelated causes, or elected to have open repair. CONCLUSIONS: Postoperative elongation of the infrarenal aortic neck may create the radiographic perception of migration without necessarily causing a loss of proximal stent graft fixation. Patients with a total loss of the proximal seal zone actually have infrarenal aortic neck shortening, with a degree of neck dilatation beyond initial device oversizing that may compromise proximal fixation length. Conversely, those with an intact proximal seal zone demonstrate aortic neck elongation equivalent to migration, with no loss of proximal fixation length; these patients have a benign natural history without intervention. Thus, aortic neck dilatation beyond oversizing, aortic neck shortening, and loss of proximal fixation length are more clinically relevant predictors of proximal stent graft failure than simple migration distance.  相似文献   

18.
Aortic valve-sparing root reconstructive surgery has been widely adopted to improve the patient's quality of life. We experienced a patient who required reoperation for progressive aortic regurgitation 17 months after the initial operation of valve-sparing root reconstruction with the reimplantation method in acute aortic dissection. In this study, we were concerned with valve durability because of the absence of sinuses of Valsalva in the new aortic root and the need for careful follow-up after this procedure.  相似文献   

19.
OBJECTIVE: Dilation of aortic annulus, sinuses of Valsalva, and sinotubular junction (STJ) diameters are the characteristic lesions of aortic root aneurysm. The remodeling technique reduces STJ diameter and creates three neosinuses of Valsalva. Alternatively, the reimplantation technique reduces both annulus and STJ diameters to the detriment of aortic root dynamics. Although the remodeling technique is recognized as the most physiological valve-sparing procedure, aortic annulus dilation may jeopardize its results. A standardized approach that combines an external subvalvular aortic prosthetic ring annuloplasty with the remodeling technique is suggested. METHODS: Eighty-three patients underwent an elective aortic root remodeling procedure, either isolated (group 1, n=34) or combined with an external subvalvular aortic prosthetic ring annuloplasty (group 2, n=49). Preoperative aortic regurgitation was 1.59+/-1.1 (group 1) and 1.97+/-1.3 (group 2) (NS). The aortic annulus was more dilated in group 2 than in group 1 (27+/-2.77 mm vs 26.4+/-2.3 mm, p<0.01). Residual aortic regurgitation > or =grade II was the conversion criteria for aortic valve replacement. RESULTS: Operative mortality was 3.6% (n=3). Intraoperative conversion for valve replacement was 32.7% in group 1 (n=11) versus 4.2% in group 2 (n=2) (p<0.001). In group 1, preoperative annulus diameter was larger for converted than for valve-spared patients (27.6+/-1.7 mm vs 25.2+/-1.5 mm, p<0.02). In group 2, implanted aortic ring significantly reduced annulus diameter (20.6+/-1.8 mm) without significant aortic valve gradient (8.3+/-3 mmHg). Follow-up was 17.2+/-13.4 months (group 1) and 10.41+/-7.95 months (group 2). Reoperation for recurrent aortic regurgitation was 13% in group 1 (n=3) versus 4.2% in group 2 (n=2). Echocardiographic follow-up found residual aortic regurgitation < or =grade I in 17 patients in group 1 (90%) versus 43 patients in group 2 (95.5%) and of grade II in two patients in group 1 (10%) and two patients in group 2 (4.5%). CONCLUSION: The addition of external aortic prosthetic ring annuloplasty improves the remodeling technique's operative reproducibility and short-term results. Therefore, its use as a systematical adjunct to the remodeling procedure is suggested. However, further long-term evaluation comparing this valve-sparing procedure to composite graft replacement should define the best surgical strategy for aortic root aneurysm.  相似文献   

20.
OBJECTIVE: Most patients with annuloaortic ectasia are young. They are at risk for complications related to a lifetime of anticoagulation when composite grafts containing mechanical valves are used for reconstruction. The majority of patients have near normal valve cusps. Valve-preserving techniques have been developed to maintain valve function and avoid anticoagulation. The eddy currents occurring within the sinuses of Valsalva in the natural aortic root have been shown to be important in the smooth, gradual, and gentle closure of the valve. Compliance of the sinuses is important in reducing stress in the leaflets. A novel ascending aortic prosthesis with "built in" compliant sinuses (Robicsek-Thubrikar graft) was developed for clinical aortic root replacement. METHODS: Woven Dacron tubes were used to make the prostheses. Three precisely measured square pieces were cut to make the expandable, individual sinuses. Sewing the individual neo-sinuses to a scalloped end of the Dacron tube graft created the neo-sinotubular junction and sinotubular ridge. Five patients with annuloaortic ectasia underwent valve-preserving aortic root reconstruction. RESULTS: All intraoperative transesophageal echocardiographic images after the valve-preserving procedure showed a normal appearing root with 10% radial expansion of each sinus in systole. The space between the cusps and neo-sinus wall in systole was normal. No patient has more than mild aortic regurgitation. CONCLUSIONS: Valve-preserving aortic root reconstruction with a novel Dacron prosthesis with compliant "built in" sinuses re-establishes normal aortic root geometry with near normal valve motion. This may enhance the durability of the valve-preserving operation.  相似文献   

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