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.     

Matrix metalloproteinase expression in the ascending aorta and aortic valve

Extracellular matrix degradation and increased proteolytic enzyme (matrix metalloproteinase (MMP)) activity characterise abdominal aortic aneurysm formation. Post-stenotic dilatation of ascending aorta is associated with aortic stenosis and regurgitation, haemodynamically normal bicuspid aortic valve (BAV) and following AV replacement. We aimed to determine an association between ascending aortic pathology and abnormal AV, with particular reference to MMPs, and ascertain differences between BAV and tricuspid (TAV) AV. Subset of the study population (n=19) with a preoperative ascending aorta of >4 cm was analysed. Samples of ascending aorta and AV were obtained from 82 patients (TAV, n=54, BAV, n=28) undergoing surgery. Gene expression of MMP-1, -2, -9 and tissue inhibitor of metalloproteinase (TIMP)-1 and -2 was quantified by real-time RT-PCR. No significant difference was seen in gene expression level of MMPs, TIMPs and ratio of MMPs/TIMPs in ascending aorta and AV between patients with BAV and TAV. MMP-2/TIMP-1 in ascending aorta was greater in BAV, in the subset of patients with preoperative aortic dilatation (P<0.05). No difference exists in gene expression of MMPs in ascending aorta and AV between patients with BAV and TAV. However, patients with larger aortic diameters have increased MMP-2/TIMP-1. Modifying MMP expression may have a role in development of aneurysms.     

Histologic abnormalities of the ascending aorta and pulmonary trunk in patients with bicuspid aortic valve disease: clinical relevance to the ross procedure.

OBJECTIVE: Bicuspid aortic valve disease is often associated with dilation of the aortic root and ascending aorta. This study examines the histologic features of the ascending aorta and main pulmonary artery of patients with and without aortic valve disease. METHODS: Samples from ascending aorta and main pulmonary artery were obtained at the time of the operation from 20 patients with bicuspid aortic valve and 11 patients with tricuspid aortic valve disease. In addition, samples were also obtained from autopsy cases with normal aortic valve. The histologic changes were graded from 1 to 3 according to severity of degenerative changes. RESULTS: In the ascending aorta, the severity of cystic medial necrosis (P =.001), elastic fragmentation (P =.002), and changes in the smooth muscle cell orientation (P =.002) were significantly more severe in patients with bicuspid than in those with tricuspid aortic valve disease. In the pulmonary trunk specimens, those 3 histologic features were also significantly more severe in patients with bicuspid than those with tricuspid valves (P =.001, P =.01, and P =.04, respectively). Seventy-five percent of patients with bicuspid aortic valve disease had grade 3 degenerative changes, whereas only 14% of those patients with tricuspid aortic valve disease had similar degrees of degenerative changes. CONCLUSION: Patients with bicuspid aortic valve disease have more severe degenerative changes in the media of the ascending aorta and main pulmonary artery than patients with tricuspid aortic valve disease. These findings may explain root and ascending aortic dilation in patients with bicuspid aortic valve disease and pulmonary autograft dilation in certain patients after the Ross procedure.     

Matrix metalloproteinases in ascending aortic aneurysms: bicuspid versus trileaflet aortic valves

BACKGROUND: Abnormal matrix metalloproteinase (MMP) and tissue inhibitor of metalloproteinase (TIMP) expression contributes to the development of abdominal aortic aneurysms. Recent data suggest that MMP-2 and MMP-9 may also play a role in thoracic aortic disease. We sought to determine (1) whether ascending aortic aneurysms are associated with increased MMP expression and (2) whether aortic inflammation and MMP expression differ between patients with congenital bicuspid aortic valves (BAVs) and those with trileaflet aortic valves (TAVs). MATERIALS AND METHODS: Samples of ascending aortic aneurysms were obtained from 29 patients; 14 patients had BAVs and 15 had TAVs. Control ascending aorta was obtained from 14 organ donors or heart transplant recipients. Aortic histology and immunohistochemistry were performed to evaluate elastin degradation, inflammatory changes, and MMP-2 and MMP-9 expression. Aortic levels of MMP-2, MMP-9, TIMP-1, and TIMP-2 were measured using ELISA. RESULTS: Aneurysms in the TAV patients exhibited marked inflammation, high CD68 expression, diminished elastin content, increased MMP-9 expression, and normal MMP-2 levels. In contrast, BAV aneurysms were characterized by a relative lack of inflammation, preservation of elastin content, normal MMP-9 levels, and elevated MMP-2 expression. TIMP-1 and TIMP-2 levels were not significantly different among the three groups. CONCLUSIONS: Ascending aortic aneurysms exhibited increased MMP expression. The pattern of MMP expression and the degree of inflammation, however, differed between aneurysms associated with BAVs and those with TAVs. Variations in the molecular mechanisms underlying different types of thoracic aortic aneurysms warrant further investigation.     

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   

Evidence for an altered balance between matrix metalloproteinase-9 and its inhibitors in calcific aortic stenosis

BACKGROUND: Recently, aortic valve stenosis has been demonstrated to exhibit increased expression of certain matrix metalloproteinases (MMPs), and this has relevantly raised the question about possible interdependency between these and their tissue inhibitors. We sought to assess the expression of elastolytic MMPs and their inhibitors (TIMPs) in nonrheumatic aortic stenosis. METHODS: The study comprised 30 stenotic and six noncalcified human aortic valves. To measure the expression levels and the amount and molecular forms of gelatinases (MMP-2, MMP-9) and TIMPs (1, 2), in situ hybridization, gelatin zymography, and reverse zymography were carried out. Antielastin staining by a monoclonal BA-4 antibody was performed to investigate the changes of one of the main substrates of these MMPs, and to substantiate the nature of the putative MMP- synthesizing cell. The cases were also immunostained with an antibody to alpha-smooth muscle actin. Inflammatory cell characterization was managed by monoclonal mouse antibodies (UCHL-1, L26, and PGM-1). RESULTS: Compared with the controls, the calcific valves showed increased mRNA expression and activation of MMP-9, and this was associated with typical characteristics of valve disease. MMP-2 mRNA production was rare, but proMMP-2 protein was detected in all valves. In agreement with the interdependency between MMP-9 and its inhibitors, a suggestive imbalance came out in diseased valves. CONCLUSIONS: The disproportion between MMP-9 and its tissue inhibitors may favor a persistent MMP activation state within the calcific valve and likely contribute to the valvular remodeling process in the setting of developing aortic stenosis.     

Bicuspid aortic valve disease and pulmonary autograft root dilatation after the Ross procedure: a clinicopathologic study.

OBJECTIVE: Bicuspid aortic valve disease has been associated with histologic abnormalities of the aortic root. Recent reports have suggested similar alterations may exist in the pulmonary artery of patients with bicuspid aortic valve. The present study was undertaken to define the histologic condition of the aortic and pulmonary artery root in bicuspid aortic valve disease and the relationship with pulmonary autograft root dilatation after the Ross procedure. METHODS: In 17 patients undergoing aortic root replacement with the pulmonary autograft, biopsy specimens of the aortic root and pulmonary artery trunk were collected. Clinical and histologic findings of patients with bicuspid aortic valves were compared with those with tricuspid aortic valves. RESULTS: There were 9 patients (8 male, 1 female) with bicuspid aortic valve (group 1) and 8 (all male) with tricuspid aortic valve (group 2). Mean age was comparable (24.4 +/- 9.8 vs 23.6 +/- 10.8 years, P =.9). Aortic insufficiency as an indication for operation was more common in group 1 (9/9 vs 5/8, P =.007), whereas preoperative aortic root dilatation was equally prevalent (4/9 vs 1/8, P =.1). Prior aortic valve repair had been performed in 2 patients (1/9 vs 1/8, P =.9). Prevalence of cystic medionecrosis of the aortic wall was similar in the 2 groups (4/9 vs 3/8, P =.6). Cystic medionecrosis of the pulmonary artery trunk was found only in 1 patient with tricuspid aortic valve (0/9 vs 1/8, P =.3). During a mean follow-up of 26.5 +/- 12.2 months (32.1 +/- 12.7 vs 20.1 +/- 7.4 months, P =.04), prevalence of pulmonary autograft root dilatation (greater than 4.0 cm) was equally represented in patients with native bicuspid or tricuspid aortic valve (3/9 vs 2/8, P =.6). CONCLUSIONS: Histologic abnormalities of the pulmonary artery root are rare and equally prevalent in young patients with bicuspid and tricuspid aortic valves. On the contrary, root dilatation is relatively common late after autograft root replacement but appears unrelated to bicuspid aortic valve disease or to pre-existing degenerative changes of the pulmonary artery root.     

Comparative Finite Element Model Analysis of Ascending Aortic Flow in Bicuspid and Tricuspid Aortic Valve

In bicuspid aortic valve (BAV) disease, the role of genetic and hemodynamic factors influencing ascending aortic pathology is controversial. To test the effect of BAV geometry on ascending aortic flow, a finite element analysis was undertaken. A surface model of aortic root and ascending aorta was obtained from magnetic resonance images of patients with BAV and tricuspid aortic valve using segmentation facilities of the image processing code Vascular Modeling Toolkit (developed at the Mario Negri Institute). Analytical models of bicuspid (antero‐posterior [AP], type 1 and latero‐lateral, type 2 commissures) and tricuspid orifices were mathematically defined and turned into a volumetric mesh of linear tetrahedra for computational fluid dynamics simulations. Numerical simulations were performed with the finite element code LifeV. Flow velocity fields were assessed for four levels: aortic annulus, sinus of Valsalva, sinotubular junction, and ascending aorta. Comparison of finite element analysis of bicuspid and tricuspid aortic valve showed different blood flow velocity pattern. Flow in bicuspid configurations showed asymmetrical distribution of velocity field toward the convexity of mid‐ascending aorta returning symmetrical in distal ascending aorta. On the contrary, tricuspid flow was symmetrical in each aortic segment. Comparing type 1 BAV with type 2 BAV, more pronounced recirculation zones were noticed in the latter. Finally, we found that in both BAV configurations, maximum wall shear stress is highly localized at the convex portion of the mid‐ascending aorta level. Comparison between models showed asymmetrical and higher flow velocity in bicuspid models, in particular in the AP configuration. Asymmetry was more pronounced at the aortic level known to be more exposed to aneurysm formation in bicuspid patients. This supports the hypothesis that hemodynamic factors may contribute to ascending aortic pathology in this subset of patients.     

Structural and biomolecular changes in aorta and pulmonary trunk of patients with aortic aneurysm and valve disease: implications for the Ross procedure.

OBJECTIVES: A higher incidence of pulmonary autograft dilatation is assumed in patients with ascending aortic dilatation and bicuspid aortic valve disease. To examine whether structural abnormalities are present in the ascending aorta as well as in the pulmonary trunk (PT) we specifically addressed molecular mechanisms and signalling pathways for aneurysm formation in ascending aortic aneurysms and PT of patients with different aortic valve pathology undergoing an extended Ross procedure. METHODS: Wall segments resected from aortic aneurysms (20 patients, 7 bicuspid aortic valves BAV, and 13 tricuspid aortic valves TAV) and from PTs were submitted to analysis of leukocyte infiltration (immunohistochemistry), smooth muscle cell (SMC) apoptosis (in situ end-labelling of DNA-fragments TUNEL), and expression of death-promoting proteins perforin, granzyme B, Fas/FasL (immunoblotting). RESULTS: Degenerative changes including rarefication and apoptosis of SMCs were significantly more severe in BAV than TAV disease (apoptotic index 9.2+/-3.2 vs. 11.9+/-6.2, P = 0.02). Immunohistochemistry confirmed presence and activation of death-promoting mediators in aneurysmal tissue whereas pulmonary tissue displayed only few apoptotic cells, occasional Fas+cells, rarely colocalized with FasL. By Western blot analysis extracts from BAV and TAV but not pulmonary artery wall contained appreciable amounts of perforin, granzyme B, and Fas/FasL. CONCLUSION: Aneurysm formation is associated with SMC apoptosis and local signal expression of activated cells in patients with bicuspid as well as TAV. The PT itself is not pathologically involved with only minor degenerative changes. Although the disease process in the aorta appeared to be more severe in patients with BAV, there was similarity of histological and molecular changes of the pulmonary artery wall in all patients. Dilation of the pulmonary autograft seems not to be the result of histopathological and biomolecular mechanisms in the PT.     

Matrix metalloproteinase activity in thoracic aortic aneurysms associated with bicuspid and tricuspid aortic valves

OBJECTIVE: Matrix metalloproteinases are endopeptidases that function in cell matrix turnover. Abnormal matrix metalloproteinase activity has been implicated in the formation of atherosclerotic abdominal aortic aneurysms. Recent studies suggest that abnormal matrix metalloproteinase activity may also be associated with the formation of atherosclerotic and nonatherosclerotic thoracic aortic aneurysms. Bicuspid aortic valves are associated with an intrinsic aortic pathology that predisposes to formation of proximal thoracic aneurysms while tricuspid aortic valves are not. The objective of this study was to compare the activities of matrix metalloproteinases and levels of their inhibitors in thoracic aneurysms of patients with bicuspid and tricuspid aortic valves. METHODS: Endogenous and total activity of matrix metalloproteinase-2 and matrix metalloproteinase-9 were measured in proximal nonatherosclerotic thoracic aortic aneurysms of 16 patients with bicuspid aortic valves and 12 patients with tricuspid aortic valves. Levels of tissue inhibitor metalloproteinase-1 and -2 were also measured. Results were standardized to total protein (mg). RESULTS: Total matrix metalloproteinase-2 activity was greater in aneurysms associated with bicuspid valves when compared with those from tricuspid valves (43 +/- 11 ng/mg vs 14 +/- 2 ng/mg, P =.02). Total matrix metalloproteinase-9 activity was also greater in aneurysms associated with bicuspid aortic valves (4.0 +/- 0.9 vs 1.5 +/- 0.3, P =.02). There was no meaningful difference between groups in levels of tissue inhibitor-1 and -2. CONCLUSION: The increased activity of matrix metalloproteinases in the walls of aneurysms associated with bicuspid aortic valves may partly explain the predilection to aneurysm formation in these patients.     

Vascular matrix remodeling in patients with bicuspid aortic valve malformations: implications for aortic dilatation

BACKGROUND: Patients with bicuspid aortic valve malformations are at an increased risk of aortic dilatation, aneurysm formation, and dissection. Vascular tissues with deficient fibrillin-1 microfibrils release matrix metalloproteinases, enzymes that weaken the vessel wall by degrading elastic matrix components. In bicuspid aortic valve disease a deficiency of fibrillin-1 and increased matrix metalloproteinase matrix degradation might result in aortic degeneration and dilatation. METHODS: Samples of the pulmonary artery and aorta were obtained from surgical patients with bicuspid aortic valves (n = 21) and tricuspid aortic valves (n = 16). RESULTS: Fibrillin-1 content was reduced in bicuspid aortic valve aortas compared with that seen in tricuspid aortic valve aortas (P =.001), whereas the associated matrix components, elastin and collagen, were unchanged (P =.51 and P =.21). Reductions of aortic fibrillin-1 content were independent of valve function and patient age. Compared with tricuspid aortic valve aorta, matrix metalloproteinase 2 activity was increased more than 2-fold in bicuspid aortic valve aortas (P =.04) and correlated positively with aortic diameter (r = 0.74, P =.05). Matrix metalloproteinase 9 activity was not significantly different. Fibrillin-1 content was also reduced in the pulmonary arteries of patients with bicuspid aortic valves (P =.06), suggesting a systemic deficiency of fibrillin-1. Promatrix metalloproteinase 2 was increased (P =.04), reflecting an increased production of matrix metalloproteinase 2 in these fibrillin-1-deficient tissues, whereas active matrix metalloproteinase 2 and matrix metalloproteinase 9 species were unchanged, and correspondingly, the pulmonary arteries were not dilated. CONCLUSIONS: Deficient fibrillin-1 content in the vasculature of patients with bicuspid aortic valves might trigger matrix metalloproteinase production, leading to matrix disruption and dilatation. This process of vascular matrix remodeling in patients with bicuspid aortic valves offers novel therapeutic targets to prevent the aortic degeneration and dilatation characteristic of this disease.     

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.     

Outcomes of aortic valve repair according to valve morphology and surgical techniques

OBJECTIVES The aim of this study was to assess the impact of aortic valve morphology and different surgical aortic valve repair techniques on long-term clinical outcomes. METHODS Between February 2003 and May 2010, 216 patients with aortic insufficiency underwent aortic valve repair in our institution. Ages ranged between 26 and 82 years (mean 53?±?15 years). Aortic valve dysfunctions, according to functional classification, were: type I in 55 patients (25.5%), type II in 126 (58.3%) and type III in 35 (16.2%). Sixty-six patients (27.7%) had a bicuspid valve. Aortic valve repair techniques included sub-commissural plasty in 138 patients, plication in 84, free-edge reinforcement in 80, resection of raphe plus re-suturing in 40 and the chordae technique in 52. Concomitant surgical procedures were CABG in 22 (10%) patients, mitral valve repair in 12 (5.5%), aortic valve-sparing re-implantation in 78 (36%) and ascending aorta replacement in 69 (32%). Mean follow-up was 42?±?16 months and was 100% complete. RESULTS There were six early deaths (2.7%). Overall late survival was 91.5% (18 late deaths). There were 15 (6.9%) late cardiac-related deaths. NYHA functional class was ≤II in all patients. At follow-up, 28 (14.5%) patients had recurrent aortic insufficiency?≥?grade II. The freedom from valve-related events was significantly different between bicuspid and tricuspid valve implantation (P?相似文献   

Patient-specific assessment of hemodynamics by computational fluid dynamics in patients with bicuspid aortopathy

Objective

Hemodynamics related to eccentric blood flow may factor into the development of bicuspid aortic valve aortopathy. We investigated wall shear stress distribution by means of magnetic resonance imaging–based computational fluid dynamics in patients with a bicuspid aortic valve.

Valve-sparing aortic root replacement in bicuspid aortic valves: a reasonable option?

OBJECTIVES: Aortic dilatation occurs in many patients with bicuspid aortic valves. We have added root replacement using the remodeling technique originally designed for tricuspid aortic valves to bicuspid aortic valve repair for treatment of the dilated root. We compared the results of remodeling in bicuspid aortic valves with those in tricuspid aortic valves. METHODS: From October 1995 through January 2004, 60 patients underwent root remodeling for bicuspid aortic valves (group A), and 130 patients underwent root remodeling for tricuspid aortic valves (group B). Correction of cusp prolapse was more often performed in group A (group A, 50/60; group B, 47/130; P < .0001). Transthoracic echocardiography was performed at 1 week, 6 and 12 months, and every year thereafter. Cumulative follow-up was 527 patient-years (mean, 2.9 +/- 2 years). RESULTS: No patient died in group A. Hospital mortality in group B was 5% (5/100; 95% confidence interval,1.6%-11.3%) after elective operations and 10% (3/30; 95% confidence interval, 2.1%-26.5%) after emergency operations. Mean systolic gradients were identical at 1 year (group A, 4.8 +/- 2.1 mm Hg; group B, 4.0 +/- 2 mm Hg) and 5 years (group A, 4.5 +/- 2.3 mm Hg; group B, 3.9 +/- 2.2 mm Hg). Freedom from aortic regurgitation of grade 2 or higher at 5 years was 96% in group A and 83% in group B ( P = .07), and freedom from reoperation at 5 years was 98% in group A and 98% in group B ( P = .73). CONCLUSIONS: Valve-sparing aortic replacement with root remodeling can be applied to aortic dilatation and a regurgitant bicuspid aortic valve. Hemodynamic function and valve stability of a repaired bicuspid aortic valve are comparable with those seen in cases of tricuspid anatomy.     

Reoperation due to failure of a Freestyle bioprosthesis

We report re-do aortic valve and ascending aorta replacements by using the valve-on-valve technique for primary tissue failure of a Freestyle bioprosthesis. A 74-year-old male, who had had a 25 mm Freestyle bioprosthetic valve implanted by the sub-coronary method 5 years previously for aortic valve regurgitation due to congenital bicuspid valve, was referred to our hospital for dyspnea and palpitation. He presented with heart failure secondary to aortic regurgitation due to primary tissue failure, and computed tomography demonstrated an enlarged ascending aorta (5 cm in diameter). The operative findings revealed that the Freestyle bioprosthetic valve had a leaflet tear at the left coronary cusp. We replaced the degenerated Freestyle bioprosthesis with a 19 mm Mosaic aortic bioprosthesis by using the valve-on-valve technique, and ascending aorta replacement was performed simultaneously. This technique can be useful for re-do surgery for degenerated stentless valves to avoid potential risks of complete excision of the bioprosthesis.     

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.     

Should the ascending aorta be replaced more frequently in patients with bicuspid aortic valve disease?

OBJECTIVE: The optimal diameter at which replacement of the ascending aorta should be performed in patients with bicuspid aortic valve disease is not known. METHODS: We reviewed all patients with bicuspid aortic valves undergoing aortic valve replacement at our institution from 1979 through 1993 (n = 201). Patients undergoing concomitant replacement of the ascending aorta were excluded. RESULTS: Follow-up was obtained on 98% of patients and was 10.3 +/- 3.8 (mean +/- SD) years. The average patient age was 56 +/- 15 years, and 76% were male. The ascending aorta was normal (<4.0 cm) in 115 (57%) patients, mildly dilated (4.0-4.4 cm) in 64 (32%) patients, and moderately dilated (4.5-4.9 cm) in 22 (11%) patients. All patients with bicuspid aortic valves with marked dilation (>5.0 cm) underwent replacement of the ascending aorta and were therefore excluded. Fifteen-year survival was 67%. During follow-up, 44 patients required reoperation, predominantly for aortic valve prosthesis failure. Twenty-two patients had long-term complications related to the ascending aorta: 18 required an operative procedure to replace the ascending aorta (for aortic aneurysm), 1 had aortic dissection, and 3 experienced sudden cardiac death. Fifteen-year freedom from ascending aorta-related complications was 86%, 81%, and 43% in patients with an aortic diameter of less than 4.0 cm, 4.0 to 4.4 cm, and 4.5 to 4.9 cm, respectively ( P < .001). CONCLUSIONS: Patients undergoing operations for bicuspid aortic valve disease should be considered for concomitant replacement of the ascending aorta if the diameter is 4.5 cm or greater.     

Surgery of the dilated aortic root and ascending aorta in pediatric patients: techniques and results.

OBJECTIVE: Dilatation of the aortic root is a well-known cardiovascular manifestation in children and adult patients with connective tissue disease (e.g. Marfan syndrome). Dilatation of the ascending aorta is extremely rare and may be associated with bicuspid aortic valve. This report evaluates the incidence of dilatative aortic root and ascending aortic pathology in patients younger than 18 years and analyzes the results obtained after repair and replacement strategies. METHODS: Between 1/1995 and 12/2002, a total of 752 operations on the thoracic aorta were performed in adult and pediatric patients. We present our experience with a group of 26 patients <18 years of age, who required isolated surgery of the aortic root and/or ascending aorta because of a dilatative lesion. Fifteen patients had isolated aortic root dilatation (13 of them suffered from Marfan syndrome), eight patients presented with an idiopathic dilatation of the ascending aorta and three patients had dilatation in association with a bicuspid aortic valve. Mean age was 10 +/- 4.8 years (4-18 years). Repair of the aortic root with preservation of the aortic valve (Yacoub, David or selective sinus repair) was performed in nine patients, replacement using a homograft was performed in five patients, composite graft with mechanical prosthesis in two patients, with biological prosthesis in one patient and Ross operation was performed in one case. Isolated supracoronary graft replacement was performed in eight patients. RESULTS: Two patients died during hospitalization: a 10-year old girl developed respiratory failure on the 2nd postoperative day and autopsy revealed Ehlers-Danlos syndrome with a massive intrapulmonary emphysema. A 14-year-old Marfan patient with severely depressed preoperative LV function died from low cardiac output following composite-graft, mitral and tricuspid valve repair. One patient required aortic valve replacement 7 days after an aortic valve sparing root repair. There was no additional perioperative morbidity. In the long-term, two patients died from rupture of the thoracic aorta, both following minor non-cardiovascular surgical procedures. Both had normal sized descending and abdominal aorta. CONCLUSION: Repair of the aortic root and/or ascending aorta in children and adolescent patients can be performed with acceptable early and late results. While the presence of severe comorbidity may adversely affect early outcome, long-term survival was mainly determined by rupture of the descending aorta.     

Pericardial patch augmentation for repair of incompetent bicuspid aortic valves at midterm

Objective: Reoperation rates after repair of bicuspid aortic valves are higher than for mitral valve reconstruction. Satisfactory results have been reported for patch augmentation for tricuspid aortic valves. We have applied this technique for the repair of bicuspid aortic valves. Methods: Autologous pericardium is sutured to the free edge of the prolapsing bicuspid leaflet. A large coaptation surface is created and competence of the bicuspid valve is achieved. Forty patients underwent reconstruction of their bicuspid aortic valves by pericardial patch augmentation. Patients were followed up at regular intervals by echocardiography in yearly intervals. Results: There were no perioperative deaths. One year postoperatively, one patient died due to endocarditis. Seven patients (17.5%) had aortic regurgitation grade I, and the other 33 patients had non or trivial aortic regurgitation at discharge. At 4.2 ± 3.1 years postoperatively, only four patients (10%) had aortic regurgitation grade I. There were no cases of progression of regurgitation. Planimetric effective orifice areas ranged above 2 cm². Mean aortic gradients dropped from 8.2 ± 4.8 mmHg at discharge to 3.8 ± 3 at four years and the mean height of coaptation surface from 14.7 ± 2 mm to 12.3 ± 4, respectively. Conclusions: The pericardial patch augmentation technique increases coaptation surface, and thus provides reliable early and midterm competence of reconstructed bicuspid aortic valves.