Analysis of valve motion after the reimplantation type of valve-sparing procedure (David I) with a new aortic root conduit

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.     

Comparison of distensibility of the aortic root and cusp motion after aortic root replacement with two reimplantation techniques: Valsalva graft versus tube graft

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.     

One-year appraisal of a new aortic root conduit with sinuses of Valsalva.

OBJECTIVES: We evaluate the clinical results 1 year after an anatomic reconstruction of the aortic root in which we used a specifically designed aortic root prosthesis that incorporates the sinuses of Valsalva. MATERIAL AND METHODS: The new aortic Dacron prosthesis has a proximal portion in the Dacron conduit that expands on implantation, creating pseudosinuses. During a 12-month period, 28 patients (mean age 59 +/- 14 years) underwent a Bentall operation (12 cases), a remodeling procedure (7 cases), and a reimplantation procedure (9 cases) with the use of a new aortic root conduit. All patients had aortic root aneurysm with an anatomically normal (for the valve-sparing procedure) or diseased aortic valve (for the Bentall operation). Five patients had aortic dissection and 5 had Marfan disease. The mean follow-up was 6 +/- 3 months. All patients underwent postoperative transesophageal and transthoracic echocardiographic studies. RESULTS: All patients survived and were in good clinical condition at the latest follow-up. Postoperative echocardiography showed a marked reduction in ventricular volumes in all patient groups (P <.0005). In the Bentall group the new prosthesis appeared to reduce the tension on the coronary ostial sutures. In patients undergoing both types of valve-sparing procedures a similar normal anatomy of the aortic root was reconstructed. In the reimplantation group the anulus was smaller than in the remodeling group (P =.01). Patients undergoing the reimplantation procedure had less bleeding and a lower incidence of residual valve insufficiency. CONCLUSIONS: The new aortic root prosthesis allowed the reconstruction of the aortic root anatomy in all types of surgical techniques with low postoperative morbidity.     

Coronary flow characteristics after a Bentall procedure with or without sinuses of Valsalva.

OBJECTIVES: The sinuses of Valsalva are known to contribute to the normal function of the aortic valve. Little is known about their role in promoting coronary artery blood flow. The aim of this study was to compare coronary artery flow characteristics among patients undergoing a Bentall operation by means of a conventional cylindrical Dacron conduit or with a new conduit with pseudosinuses of Valsalva or in patients retaining their natural sinuses of Valsalva after aortic valve and supracoronary ascending aorta replacement. METHODS: One year after a Bentall procedure with a standard cylindrical Dacron conduit (7 patients, group A) or with the new conduit (7 patients, group B), or after aortic valve and ascending aortic replacement (control group, 7 patients, group C) coronary flow velocity reserve and diastolic to systolic time integral ratio at baseline and after maximal hyperemia (with 40 microg of adenosine) were assessed by using a 0.014-in. Doppler guidewire positioned in the middle portion of the left anterior descending coronary artery. All patients were in NYHA class I, sinus rhythm and free of coronary disease. RESULTS: Arterial blood pressures and heart rate were comparable among groups. Intracoronary Doppler measurements did not show any significant difference in coronary vascular reserve between the three groups (3.6+/-0.4 vs 3.1+/-0.7 vs 3.7+/-0.5, P = 0.2). A greater diastolic component at baseline was present in group B patients (5.5+/-1.9 vs 3.5+/-0.9 in group A and 3.7+/-0.9 in group C, P = 0.024). After maximal hyperemia the diastolic component increased slightly in group A patients (8%) while both in groups B and C significantly decreased (-15 and -20%, respectively) (P = 0.017). CONCLUSIONS: The presence of pseudosinuses of Valsalva does not influence coronary flow reserve. After maximal coronary vasodilation the increase in the systolic component of coronary flow is more evident in the presence of sinuses or pseudosinuses of Valsalva, thus suggesting that coronary flow pattern may be affected by the presence of sinuses.     

Valve-preserving aortic replacement: does the additional repair of leaflet prolapse adversely affect the results?

OBJECTIVE: Valve-preserving aortic replacement has evolved into an accepted therapeutic option for aortic ectasia with morphologically intact leaflets. Some patients, however, exhibit additional leaflet prolapse. We compared the results of established valve-preserving techniques with those of the combination of valve-preserving aortic surgery and additional repair of leaflet prolapse. METHODS: Between October 1995 and March 2000, 99 patients underwent valve-preserving root replacement by means of root remodeling or valve reimplantation for acute dissection (n = 25), chronic dissection (n = 4), or aneurysm (n = 70). In group A (63 patients) either root remodeling (n = 49) or valve reimplantation (n = 14) was performed with a standard technique. In group B (36 patients) valvepreserving aortic replacement (remodeling, n = 31; reimplantation, n = 5) was combined with repair of leaflet prolapse in the presence of bicuspid (n = 24) or tricuspid (n = 12) valve anatomy. Additional replacement of the aortic arch was required more frequently in group A (group A, n = 43; group B, n = 14; P =.006); otherwise, the groups were comparable. RESULTS: Cardiopulmonary bypass (group A, 133 +/- 31 minutes; group B, 117 +/- 30 minutes; P =.006) and myocardial ischemia times (group A, 96 +/- 25 minutes; group B, 88 +/- 20 minutes; P =.05) were significantly longer in group A. Mortality was not significantly different between groups (group A, 4.8%; group B, 0%). One patient in each group underwent secondary valve replacement, and all other patients had stable valve function. Freedom from aortic regurgitation of grade 2 or greater after 48 months was 93.0% in both groups. CONCLUSION: Repair of leaflet prolapse in conjunction with valve-preserving root replacement leads to midterm results that are equal to those of valve-preserving root replacement for morphologically intact leaflets.     

Size and distensibility of the aortic root and aortic valve function after different techniques of the ross procedure

OBJECTIVES: In the Ross procedure, 3 different techniques are used for aortic valve replacement with the pulmonary autograft: freestanding root, inclusion, and subcoronary implantation. The objective of this study was to evaluate echocardiographically the influence of the particular operative technique on dimension, distensibility, and valve function. METHODS: Between February 1990 and August 1998, the Ross procedure was performed in 111 patients (mean age, 48.6 +/- 14.1 years; range, 15.2-70.6 years), with 1 early and 1 late death, 1 autograft replacement, and 1 patient lost to follow-up. The remaining patients underwent the freestanding root (n = 9 patients), inclusion (n = 14 patients), and subcoronary techniques (n = 84 patients). Echocardiography was performed at a mean follow-up of 26 +/- 21.3 months after operation and was compared with the echocardiographic findings of the control subjects (n = 10 subjects). Root sizes were measured at the level of the anulus, sinus, and supra-aortic ridge; the distensibility was calculated as pressure strain elastic modulus and percent change of radius. RESULTS: Size and distensibility of the aortic root were normal, except for a larger diameter at the sinus level in the root technique in comparison to the subcoronary technique (P <.05; maximum diameter, 41.3 +/- 8.6 mm vs 32.6 +/- 4.0 mm). Aortic valve function was comparable among groups with low pressure gradients and most patients with no or trace aortic insufficiency. CONCLUSIONS: The freestanding root, inclusion, and subcoronary techniques in the Ross procedure provide comparable excellent hemodynamics, normal root size, and distensibility, except for the enlarged sinus diameter in the freestanding root. These results may have some impact on the operative procedure and follow-up investigations.     

Mechanisms of aortic valve incompetence: finite-element modeling of Marfan syndrome.

OBJECTIVES: Progressive aortic root dilatation and an increased aortic root elastic modulus have been documented in persons with Marfan syndrome. To examine the effect of aortic root dilatation and increased elastic modulus on leaflet stress, strain, and coaptation, we used a finite-element model. METHODS: The normal model incorporated the geometry, tissue thickness, and anisotropic elastic moduli of normal human roots and valves. Four Marfan models were evaluated, in which the diameter of the aortic root was dilated by 5%, 15%, 30%, and 50%. Aortic root elastic modulus in the 4 Marfan models was doubled. Under diastolic pressure, regional stresses and strains were evaluated, and the percentage of leaflet coaptation was calculated. RESULTS: Root dilatation and stiffening significantly increased regional leaflet stress and strain compared with normal levels. Stress increases ranged from 80% to 360% and strain increases ranged from 60% to 200% in the 50% dilated Marfan model. Leaflet stresses and strains were disproportionately high at the attachment edge and coaptation area. Leaflet coaptation was decreased by approximately 20% in the 50% root dilatation model. CONCLUSIONS: Increasing root dilatation and root elastic modulus to simulate Marfan syndrome significantly increases leaflet stress and strain and reduces coaptation in an otherwise normal aortic valve. These alterations may influence the decision to use valve-sparing aortic root replacement procedures in patients with Marfan syndrome.     

Results of surgery for aortic root aneurysm in patients with Marfan syndrome

OBJECTIVES: This study was undertaken to examine the long-term results of surgery for aortic root aneurysm in patients with Marfan syndrome. METHODS: Forty-four patients underwent aortic root replacement and 61 underwent aortic valve-sparing operations for aortic root aneurysm. Patients who underwent aortic root replacement had more severe symptoms, worse left ventricular function, more severe aortic insufficiency, and larger aortic root aneurysms than did patients who had aortic valve-sparing operations. Two types of valve-sparing operations were performed: reimplantation of the aortic valve in 39 patients and remodeling of the aortic root in 22 patients. Echocardiography was performed annually during follow-up. The mean follow-ups were 75 +/- 54 months for the aortic root replacement group and 49 +/- 38 months for the aortic valve-sparing group. RESULTS: There were 1 early death and 7 late deaths; 6 deaths were in the aortic root replacement group and 2 were in the aortic valve-sparing group. Survivals at 10 years were 87% in the aortic root replacement group and 96% in the aortic valve-sparing group (P =.3). Freedoms from reoperation at 10 years were 75% in the root replacement group and 100% in the valve-sparing group (P =.1). Freedoms from valve-related mortality and morbidity were 65% after root replacement and 100% after valve-sparing operation (P =.02). Freedom from aortic insufficiency greater than 2+ after aortic valve-sparing operations was 75% at 10 years and was similar for both types of valve-sparing operations; however, the diameters of the aortic annulus and neoaortic sinuses increased only after the remodeling procedure. CONCLUSIONS: This study suggests that aortic valve-sparing operations provide similar survival but lower rates of valve-related complications than aortic root replacement for patients with Marfan syndrome. Reimplantation of the aortic valve may be more appropriate than remodeling of the aortic root to prevent dilation of the aortic annulus, and for this reason we now use only this technique to treat patients with Marfan syndrome.     

Aortic valve-sparing operations in patients with aneurysms of the aortic root or ascending aorta

BACKGROUND: Aortic valve-sparing operations are an alternative to aortic root replacement in patients with aortic root aneurysms, or aortic valve replacement and supracoronary replacement of the ascending aorta in patients with ascending aorta aneurysms and dilated sinotubular junctions with consequent aortic insufficiency. METHODS: From 1988 to 2001, 230 patients underwent aortic valve-sparing operations for aortic root aneurysms (151 patients) or ascending aortic aneurysms with aortic insufficiency (79 patients). Two types of aortic valve-sparing operations were performed in patients with aortic root aneurysms: reimplantation of the aortic valve and remodeling of the aortic root. Mean follow-up was 3.8 +/- 2.8 years. RESULTS: Patients with aortic root aneurysms were younger, had less severe aortic insufficiency, less extensive vascular disease, and better left ventricular function than patients with ascending aorta aneurysms. The 8-year survival was 83% +/- 5% for the first group and 36% +/- 14% for the second. The freedom from aortic valve reoperation at 8 years was 99% +/- 1% for the first group and 97% +/- 2% for the second. In patients who had aortic root aneurysms, 3 developed severe aortic insufficiency (AI), and 15 developed moderate AI, for an 8-year freedom from significant AI of 67% +/- 7%. But freedom from AI was 90% +/- 3% after the technique of reimplantation, and 55% +/- 6% after the technique of remodeling (p = 0.02). In patients with ascending aortic aneurysms, the freedom from AI greater than 2+ at 8 years was 67% +/- 11%. CONCLUSIONS: The long-term results of aortic valve sparing for aortic root aneurysms are excellent, and reimplantation of the aortic valve may provide a more stable repair of the aortic valve than remodeling of the aortic root.     

Aortic prosthetic ring annuloplasty: a useful adjunct to a standardized aortic valve-sparing procedure?

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.     

Replacement of the aortic root for acute prosthetic valve endocarditis: prosthetic composite versus aortic allograft root replacement

OBJECTIVE: Aortic root replacement for prosthetic aortic valve endocarditis with accompanying destruction of the aortic root is a well-established surgical intervention. However, there is still no consensus whether prosthetic material or allogeneic material should be used. Here we report on our experience with prosthetic composite and aortic allograft root replacement in such patients during a 10-year interval. METHODS: From 1991 through 2001, 29 patients with prosthetic aortic valve endocarditis combined with aortic root destruction underwent reoperation at our institution. Sixteen patients received aortic root replacement with a cryopreserved aortic root allograft (group A) and 13 with a prosthetic composite graft (group B). The interval between the initial operation and reoperation was 29 months (range, 5-168 months) in group A and 55 months (range, 7-248 months) in group B. RESULTS: Hospital mortality was 18.5% (n = 5 patients, 3 in group A and 2 in group B). Median follow-up was 21 months (range, 1-48 months) for group A and 34 months (range, 1-152 months) for group B (P >.2). Survival at 1 and 5 years was 81% +/- 10% and 81% +/- 10% in group A and 85% +/- 10% and 85% +/- 10% in group B, respectively. No patient underwent reoperation for recurrent prosthetic aortic valve endocarditis. CONCLUSIONS: Our results indicate that excellent long-term results can be achieved regardless of the material used for aortic root replacement in patients with prosthetic aortic valve endocarditis.     

In vitro evaluation of a new aortic valved conduit

BackgroundThis study examined whether the presence of a sinus of Valsalva equivalent in the KONECT RESILIA aortic valved conduit (Edwards Lifesciences, Irvine, Calif) improves valve hemodynamics, kinematics, and performance.MethodsA 28-mm KONECT RESILIA aortic valved conduit was used to create an in vitro flow test model, and the same aortic valved conduit model without a sinus section was used as a control. Particle image velocimetry and hydrodynamic characterization experiments were conducted in the vicinity of the valves in a validated left-heart simulator at 3 cardiac output levels. In addition, leaflet kinematics of the valves were determined through en face high-speed imaging.ResultsThe KONECT RESILIA aortic valved conduit model exhibited lower mean and peak transvalvular pressure gradients than the control model at all 3 cardiac outputs. In addition, its leaflets opened more fully than did those of the valved conduit without the sinuses, yielding greater effective and geometric orifice areas. It was found that the presence of the sinuses not only facilitated the development of larger and more stable vortices at the initial stages of the cardiac cycle but also helped to maintain these vortices during the late stages of the cardiac cycle, leading to smoother valve closure.ConclusionsThe KONECT RESILIA aortic valved conduit reproduces the bulged section of the aortic root corresponding to the sinuses of Valsalva. With this Valsalva-type conduit, larger orifice areas were observed, improving valve hemodynamics that may enhance performance.     

Midterm results after aortic valve-sparing operation

OBJECTIVES: We have conducted aortic valve-sparing operation for patients having aortic root dilatation and almost normal aortic valve leaflets since August 1998, and here report midterm results. METHODS: Patients with dilated aortic annulus or Marfan's syndrome were treated with reimplantation, and the remaining patients with remodeling. Either 24 or 26 mm graft was selected based on aortic annular diameter and leaflet size. Aortic valve competence was assessed regularly with echocardiography. RESULTS: Five patients (age: 29 +/- 13 yr), including 4 with Marfan's syndrome, had undergone reimplantation, and 3 (age: 46 +/- 18 yr) remodeling by December 2000. Mean follow-up was 18 (range: 10-32) months, and no postoperative death has occurred and no reintervention has been required thus far. All the patients in the remodeling group showed only a small pressure gradient through the aortic valve and decreased left ventricular diameter. Two in the reimplantation group showed a pressure gradient exceeding 20 mmHg. Two Marfan's syndrome patients in the reimplantation group showed slightly increased diastolic left ventricular diameter and 3 slightly increased systolic left ventricular diameter. Although aortic regurgitation had diminished in all patients by discharge, moderate aortic regurgitation recurred in 1 non-Marfan's syndrome patient in the reimplantation group because of degenerated aortic valve. CONCLUSION: Although postoperative aortic valve function was not perfect in all patients undergoing reimplantation, midterm results after aortic valve-sparing operation were generally satisfactory. Proper selection of patients, procedures, and graft size was thought to be important to ensure a favorable surgical outcome.     

Computational simulations of the aortic valve validated by imaging data: evaluation of valve-sparing techniques

The goal of this study has been to develop a numerical model of the aortic valve, to validate it with in-vivo data and to computationally evaluate the effect of two types of aortic valve-sparing reconstructions on valve dynamics and hemodynamics. A model of the native aortic valve and two models of the valve after surgical reconstruction (reimplantation with a straight conduit and remodeling with a shaped conduit) were created. These models were transferred to a finite element analysis software where the interaction between valve structures and blood was taken into account in a dynamic manner. Leaflet and blood dynamics, as well as tissue compliance and stresses were evaluated. Leaflet dynamics and blood velocities were also assessed by magnetic resonance imaging in 15 healthy volunteers. Computational results in the native valve model correlated closely with the in-vivo imaging data. The creation of neo-sinuses was shown to restore leaflet opening and closing dynamics. Loss of compliance at the commissures led to altered stress distribution patterns. Preservation of sinus geometry was an important factor in end systolic vortex formation. This is the first study to have incorporated the effect of blood flow in the numerical evaluation of aortic reconstructions using a computational model validated by in-vivo data. Differences in valve dynamics after surgical reconstruction reported in this computational study match trends previously reported in other in-vivo studies. Numerical models such as this one can serve as increasingly sophisticated tools in the study of aortic valve pathologies and in the optimization of new surgical reconstruction techniques.     

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.     

Further insights into normal aortic valve function: role of a compliant aortic root on leaflet opening and valve orifice area

BACKGROUND: This study aims to find the fundamental differences in the mechanism of opening and closing of a normal aortic valve and a valve with a stiff root, using a dynamic finite element model. METHODS: A dynamic, finite element model with time varying pressure was used in this study. Shell elements with linear elastic properties for the leaflet and root were used. Two different cases were analyzed: (1) normal leaflets inside a compliant root, and (2) normal leaflets inside a stiff root. RESULTS: A compliant aortic root contributes substantially to the smooth and symmetrical leaflet opening with minimal gradients. In contrast, the leaflet opening inside a stiff root is delayed, asymmetric, and wrinkled. However, this wrinkling is not associated with increased leaflet stresses. In compliant roots, the effective valve orifice area can substantially increase because of increased root pressure and transvalvular gradients. In stiff roots this effect is strikingly absent. CONCLUSIONS: A compliant aortic root contributes substantially to smooth and symmetrical leaflet opening with minimal gradients. The compliance also contributes much to the ability of the normal aortic valve to increase its effective valve orifice in response to physiologic demands of exercise. This effect is strikingly absent in stiff roots.     

主动脉根部外科解剖及其与毗邻结构关系

目的：测量主动脉根部不同高度的口径大小，并观察主动脉窦与邻近结构的关系。方法：用30例正常成人甲醛固定心脏标本，测量主动脉根部不同高度的口径和主动脉瓣的大小，观察主动脉窦与邻近结构的关系。结果：（1）主动脉窦中部（Sinus)＞主动脉窦管结合部上1cm(STJ1)＞主动脉窦管结合处（STJ0）＞主动脉瓣环基底（Base）。经方差分析检验，P＜0．05，说明主动脉根部4个高度口径大小的差别具统计学意义。（2）主动脉瓣的瓣高、瓣附着缘长和瓣游离缘长的测量结果显示。（3）二尖瓣前瓣中轴线与主动脉窦的关系显示，二尖瓣前瓣中轴线86．6％位于左冠状动脉窦与无冠状动脉窦之间。（4）右心房主动脉隆凸与主动脉窦的关系显示，右心房主动脉隆凸由无冠状动脉窦形成者占73．3％，由无冠状动脉窦和右冠状动脉窦共同形成者占26．7％。（5）左、右肺动脉瓣交界点与主动脉窦的关系显示，左、右肺动脉瓣交界点对向左、右冠状动脉窦之间者占80％。结论：测量结果有助于心外科手术的开展。     

Aortic root reconstruction with preservation of native aortic valve and sinuses in aortic root dilatation with aortic regurgitation.

BACKGROUND: We assessed the results of a modified technique for aortic root reconstruction including preservation of the native aortic valve and sinuses. METHODS: A modified technique for reconstruction of the aortic root was devised in which the native aortic sinuses are preserved and remodeled, the diameter of the sinotubular junction is reduced, the ventriculoaortic junction is reinforced with a Dacron prosthesis, and the coronary ostia are reimplanted. Since January 1995, this modified operative technique was performed in 13 patients with a mean age of 54 +/- 21 years. The median grade of aortic regurgitation was 3; in 10 patients it was caused by dilatation of the sinotubular junction, and 3 had additional annuloaortic ectasia. RESULTS: The aortic crossclamping time was 61 +/- 18 minutes. In-hospital mortality was 2 of 13 (15. 3%) patients, both deaths being related to complications of aortic dissection. In 1 patient aortic regurgitation increased to grade 3, necessitating aortic valve replacement. At a mean follow-up of 2.1 years, the remaining 10 patients had stable aortic valve function with a median grade of regurgitation of 1. The mean New York Heart Association functional class was 1.2. CONCLUSIONS: Aortic root reconstruction with preservation of the native aortic valve and sinuses allows symmetric reconstruction of the aortic sinuses and adaptation of the diameters of the sinotubular and ventriculoaortic junctions, thus optimizing aortic valve function. Moreover, it prevents contact of the aortic valve leaflets with the Dacron graft, which may enhance the durability of the repair.     

Surgical treatment for aortic periannular abscess/pseudoaneurysm caused by infective endocarditis

Delayed diagnosis or surgery sometimes causes more extensive destruction of aortic periannular abscess, or pseudoaneurysm, resulting in left ventricular–aortic discontinuity, particularly in patients with prosthetic valve endocarditis. The condition complicates the surgical procedures and causes worsening of short- and long-term outcomes. In-hospital mortality in patients with prosthetic valve endocarditis has been reported to be as high as 15–20 %, even at leading hospitals in the world. Contemporary modes of surgery for periannular abscess/pseudoaneurysm involve drainage of the cavity, radical debridement of necrotic tissue, annular reconstruction of the destroyed annulus, and root replacement using an optimal conduit. Radical debridement is of primary importance and is the universally accepted procedure, which frequently requires annular reconstruction using a pericardial patch. Conventional aortic valve replacement using a mechanical or stented biological valve, aortic valve replacement with translocation, aortic root replacement using an allograft, pulmonary autograft (Ross procedure), stentless biological valve, or a composite graft are conduits of choice. All things considered, allograft is believed to be the best conduit for a destroyed annulus because of better fit and its resistance to infection; however, recent reports have failed to confirm the superiority of allograft over other conduits in terms of long-term survival and freedom from reoperation/recurrence of infection. Short- and long-term outcomes have been studies for every type of conduit, but the selection of conduits for aortic root replacement is still controversial.     

Half-leaflet suspension with a thin Gore-Tex suture for aortic leaflet prolapse

The treatment of aortic root dilatation accompanied by a leaking valve requires a multimodal approach involving root reimplantation or remodeling with tailoring of the sinotubular junction or valvular apparatus, or both. We report a patient with annuloaortic ectasia with a leaking valve that was successfully treated by performing aortic valve repair and root reimplantation. The operation was performed by placing a thin Gore-Tex CV7 suture (W. L. Gore and Assoc, Flagstaff, AZ) halfway along the prolapsed right coronary leaflet to suspend the leaflet. By using this surgical technique, we easily repaired the prolapsed leaflet by meticulously adjusting the length of the edge of the diseased leaflet.