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1.
OBJECTIVES: The outcome of patients undergoing aortic valve replacement (AVR) may be affected by the influence of prosthesis-patient mismatch on left ventricular mass regression. However, due to the discrepancies in labeled valve size, size of sizer and actual valve dimension, it is difficult to compare different valve types. In order to perform an objective comparison, this study was designed to compare the hemodynamics of the Edwards Lifescience pericardial (ELP) and the Medtronic Mosaic porcine (MM) bioprosthesis between patients receiving the same valve size and between patients with the same aortic annulus diameter. METHODS: This prospective, randomized study was performed on 81 hospital survivors out of 86 patients undergoing AVR with either the ELP (n=39) or the MM (n=42) bioprosthesis. Intra-operative randomization was performed after the surgeon had excised the aortic valve, measured the size of the aortic annulus with three different sizers (ELP, MM and a set of metric sizers), and decided which size he would implant for either of the valve types. All valves were implanted in supra-annular position with the same implantation technique. Echocardiographic follow-up was performed early postoperatively and 6 months thereafter. RESULTS: In 12 (31%) of the patients receiving the ELP-valve, as compared to 3 (7.1%) of the patients receiving the MM-valve, the labeled valve size was smaller than the aortic annulus diameter (P<0.05). Early postoperatively, mean (17.4+/-3.1 vs 20.3+/-3.6 mmHg) and peak gradients (30.1+/-4.8 vs 37.6+/-9.6 mmHg) for the 21 mm ELP-valve were lower than for the 21 mm MM-valve (P<0.05). All other hemodynamic parameters did not show significant differences at any time point. When the same aortic annulus diameter was taken as a reference, there were no significant hemodynamic differences between either valve type at any time point, regardless of the valve size implanted. CONCLUSIONS: This study demonstrates that the hemodynamic performance of the ELP and the MM bioprosthesis are comparable when the same aortic annulus diameter is taken as a reference. The significant variabilities between different valve types with regard to labeled valve size, valve-sizer size and actual valve size have to be taken into account, when hemodynamic comparisons are performed.  相似文献   

2.
OBJECTIVES The recent introduction of transcatheter aortic heart valves into clinical practice has driven the need to develop methodologies to size such valves without access to the annulus in the manner hitherto possible with open heart surgery. To date, sizing has largely been done according to manufacturer-supplied guidelines based on transoesophageal echocardiography or multidetector computed tomography. We sought to examine how the diameter of the aortic valve annulus stretches under typical pressures encountered in normal and diseased states. In particular, we sought to measure how the area-derived diameter, Dcsa, i.e. the diameter derived from a cross-sectional area, varies with distending pressure. METHODS We conducted testing on 14 explanted pig hearts. Placing each heart in a 37°C bath, an EndoFLIP EF-325 catheter (Crospon, Galway, Ireland) was introduced into the aortic valve transapically. The catheter allows intra-balloon pressure and up to 16 area-derived diameters to be measured simultaneously, thus permitting the shape of a lumen to be observed. By dividing the minimum area-derived diameter by distending pressure, a measure of distensibility (mm/mmHg) could be determined. Once the balloon was centred, balloon pressure was ramped between 100 and 200?mmHg, and the area-derived diameter was calculated at each pressure. RESULTS Between 100 and 200?mmHg, the mean (SD) increase in diameter was found to be 3.0 (1.5) mm. Distensibility in the different hearts ranged from 0 to 0.05?mm/mmHg. In some cases, the diameter change over the pressure range was negligible, whereas in one case, the diameter change over the range was 5?mm. Whereas different nominal values of diameter are to be expected, a significant variation in the degree of distensibility was observed. CONCLUSIONS Distensibility of the aortic valve annulus is highly variable. Measurement of this parameter in addition to nominal annulus diameter may suggest occasions where a larger transcatheter aortic-valve implantation valve than would be suggested by annulus diameter measurement alone, could be deployed safely with an objective of reducing regurgitation where the annulus is sufficiently distensible.  相似文献   

3.
Aortic valve replacement was performed in 2 patients with severe aortic stenosis. They showed severe calcified valve and narrow aortic annulus. The aortic annulus was enlarged to 22 mm and 23 mm in diameter in each patient by the technique of Nicks. Then aortic valve replacement was performed with Medtronic-Hall valve (#21) which is supposed to get larger valve area than Bj?rk-Shiley valve. They had good operative course except a complication of complete AV block in the first patient. In this patient a DDD pacemaker was implanted 19 days after operation. Cardiac catheterization was performed 11 or 12 months after operation and good hemodynamics was obtained in both patients. The aortic mean pressure gradient was 6 and 5 mmHg at rest, and 9 and 13 mmHg during exercise on bicycle ergometer in each patient. The aortic valve area was 1.7 and 1.9 cm2, respectively. Body surface area in these patients was 1.29 and 1.36 m2. We concluded that in the small patients we could get a good result with Medtronic Hall valve (#21).  相似文献   

4.
Congenital bicuspid aortic stenosis is often an indication for aortic valve replacement in young adults and children. However, when the coronary ostia are exactly 180 degrees opposite each other, placing a trileaflet human allograft with freehand technique can be difficult. The described technique enlarges the left ventricular outflow tract beginning at the annulus level, using only allograft tissue. In addition to allowing placement of a larger allograft, this method rotates the coronary ostia toward each other, converting the aortic root to three-sinus anatomy.  相似文献   

5.
Accurate preoperative knowledge of the aortic annular diameter is a great value in determining the appropriate procedure for aortic valve stenosis. We have successfully used magnetic resonance imaging (MRI) to evaluate the size of the aortic annular diameter preoperatively. Between October 1997 and October 1998, 5 aortic valve replacements were performed in patients with aortic valve stenosis. MRI was performed preoperatively in all cases. All images were gated to the R-wave of the electrocardiogram. Images representing 5 mm slices were acquired in the plane which is parallel to the line through the center points of the aortic root and left ventricle outflow tract. The maximum diameter of the aortic annulus (D) was measured at the point just below the attachment of the aortic valve leaflets. This diameter was compared to the maximum diameter of the prosthetic valve sizer (D 1) which could be easily inserted into the aortic annulus intraoperatively, and to the diameter of the prosthetic valve (D 2) that ultimately was implanted. Twenty-five minutes were required to scan each patient. There were no complications related to scanning. Mean values were D = 23.4 mm, D 1 = 22.3 mm and D 2 = 21.4 mm. There was a significant correlation between D and D 1, and D 2 was approximately 2 mm smaller than D. MRI evaluation is an accurate, noninvasive method for determining the aortic annular diameter preoperatively. We highly recommend this method for measuring the aortic annular diameter in case of aortic valve stenosis as part of the preoperative evaluation.  相似文献   

6.
To avoid the problem of valve prosthesis/patient mismatch in the late postoperative period, we have adopted patch enlargement of the small aortic annulus in 33 patients having undergone aortic valve replacement since 1975, when the aortic annulus could not accept a large enough prosthesis. The mean age was 40 years, including 2 children aged 4. The technique of patch enlargement utilized was Nicks' method wherein the incision does not extend onto the mitral leaflet. In 31 adult patients, the aortic annulus before enlargement ranged in diameter from 18 to 24 mm with an average of 20.8 mm. After enlargement, the diameter of the annulus was 25.0 mm on average. In 2 children, the mean diameter of the annulus was enlarged from 16.5 mm to 20.5 mm. There were 2 early deaths in the initial series and 2 late deaths. Patch enlargement of the small aortic annulus is a simple, safe, and effective adjunct permitting the insertion of a valve one or two sizes larger than that which could be accommodated by the native annulus.  相似文献   

7.
Background. Extensive experience has accumulated with the use of aortic and pulmonary autografts for replacement of the aortic valve and the aortic root. Three general techniques for insertion have been used: subcoronary (free-hand) valve implantation, mini- or inclusion-root implantation, and aortic root replacement. Thirty-day mortality for elective operations with all of these techniques has not exceeded 5%. Thromboembolic episodes have been rare, and endocarditis has occurred infrequently. Early hemodynamic performance has been excellent, without significant gradients or valve regurgitation in the majority of patients.

Methods and Results. Progressive aortic regurgitation has been observed with continued follow-up, and is the most important complication of both types of valves. Leaflet failure and technical problems are the major causes of reoperation for patients receiving aortic allografts. There is some evidence to suggest that the prevalence of these complications is lower with the root replacement technique than with the intraaortic implantation methods.

Conclusions. Reoperation for regurgitation of the neo-aortic valve is the major complication of the pulmonary autograft procedure. The incidence of reoperation appears to be lowest with the root replacement technique. Certain conditions (acute rheumatic fever, juvenile rheumatoid arthritis, systemic lupus, ankylosing spondylitis, Libman-Sachs endocarditis, and possibly a dilated aortic root) may be contraindications to the use of a pulmonary autograft. Reoperation on the pulmonary allograft that is used to replace the autograft may be necessary in up to 20% of patients at 20 years.  相似文献   


8.
Recent reports have shown that aortic valve replacement in elderly patients over 65 years with atherosclerotic aortic stenosis and a small aortic annulus is possible by using a small sized bioprosthesis (Carpentier-Edwards pericardial valve). Here we present out surgical technique. Firstly, the native calcified aortic valve was removed completely to gain total exposure of the surrounding aortic root and sinus of Valsalva like Bentall procedure. Secondly, a small sized bioprosthesis was implanted with intermittent noneverting mattress 2-0 sutures with spaghetti and small polytetrafluoroethylene (PTFE) felt. Aortic annulus is the dilated by inserting Hegar dilator sizing from 25 to 27 mm. Therefore, aortic valve replacement for small aortic annulus in intra- or supra-annular position should be easily accomplished. Good surgical results and hemodynamic state were achieved in 25 consecutive cases using this technique.  相似文献   

9.
D R Clarke 《The Annals of thoracic surgery》1991,52(3):669-73; discussion 673-5
The extended aortic root replacement technique is used for the surgical repair of left ventricular outflow tract obstruction complicated by concurrent hypoplastic aortic annulus, multiple levels of obstruction, or aortic insufficiency. Extended aortic root replacement incorporates the concepts of aortic root replacement and aortoventriculoplasty to create a comparatively simple procedure. Unique features of the technique include the implantation of an allograft, which makes the need for anticoagulation obsolete, and use of the donor mitral leaflet to enlarge the outflow tract. Since 1985, 32 patients in Denver have undergone placement of a cryopreserved aortic valve allograft as part of extended aortic root replacement. There were four hospital deaths (13%), and 1 child underwent cardiac transplantation 30 hours after operation. In 6 months to 4.8 years of follow-up, a 14-year-old boy with familial hyperlipidemia required coronary artery bypass grafting, and 3 children experienced allograft calcification with progressive insufficiency, which prompted allograft replacement. The other 23 patients are clinically well.  相似文献   

10.
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.  相似文献   

11.
Improvements in cryopreservation techniques have made possible excellent long-term results using aortic valve allografts. Few studies, however, have examined the echocardiographic characteristics of allograft aortic valves and postoperative valve function. Aortic allograft function was eveluated in 16 patients by intraoperative transoesophageal echocardiography, postoperative catheterization, and angiography. The mean(s.d.) coaptation zone length of the allograft leaflet was significantly greater (7.3(1.4) mm) than that of the normal aortic valve (3.2(0.8) mm) (P < 0.01). No regurgitation was noted in any patients with coaptation zone length of 7–11 mm (P < 0.01). The increment of the leaflet coaptation zone length did not produce a significant pressure gradient during exercise and appeared to be one of the important mechanisms for the prevention of postoperative aortic regurgitation, because commissural orientations may be distorted in the new aortic position. This finding is consistent with the report that allografts with the largest diameter implantable in the recipient annulus should be selected for use.  相似文献   

12.
BACKGROUND: The purpose of this study was to determine whether significant regression of left ventricular hypertrophy is seen after implantation of small sizes (19 to 23 mm) of the Carpentier-Edwards (CE) pericardial valve, a stented pericardial valve. METHODS: Echocardiograms and electrocardiograms (ECGs) were performed at least 1 year after surgery (mean 18 months) in patients with 19-, 21-, and 23-mm CE pericardial aortic valves and compared with preoperative echocardiograms and ECGs. RESULTS: A total of 41 patients, mean age 79 +/- 9 years (range 46 to 93 years), were studied, including 7 19-mm, 22 21-mm, and 12 23-mm patients. The mean postoperative gradient was 22 +/- 7 mm Hg for 19-mm valves, 18 +/- 5 mm Hg for 21-mm valves, and 16 +/- 4 mm Hg for 23-mm valves. The postoperative valve areas were 1.1 +/- 0.3 cm2 for the 19-mm, 1.3 +/- 0.3 cm2 for the 21-mm, and 1.5 +/- 0.4 cm2 for the 23-mm valves. Left ventricular end diastolic diameter, end systolic diameter, septal thickness, and posterior wall thickness all decreased significantly (p <0.05) postoperatively. The proportion of patients with significant left ventricular hypertrophy on ECG decreased from 63% to 47% (p = 0.001). Left ventricular mass decreased significantly by echocardiography from 265 g preoperatively to 208 g postoperatively (p = 0.004). Left ventricular mass decreased for each valve size, and the greatest absolute reduction in mass occurred in the 19-mm valve recipients. CONCLUSIONS: Implantation of the 19-, 21-, and 23-mm CE pericardial valves results in significant reductions in left ventricular mass. These findings suggest that stented pericardial valves can be used in the small aortic root without the need for aortic root enlargement procedures.  相似文献   

13.
One hundred twenty-nine consecutive patients underwent isolated aortic valve replacement with the Hancock porcine xenograft between July, 1974, and December, 1976. The hospital mortality rate was 3.9 percent. No patient was treated with anticoagulants, and valve-related complications were extremely rare. The smaller prosthetic sizes (19 and 21 mm. stent diameter) should be used with extreme caution, and the 19 mm. prosthesis should probably never be used in the audult patient. Two methods of managing the small aortic root are emphasized: one to avoid using the smaller prosthetic size in adults and the other to alter greatly the root size in children who have a hypoplastic aortic annulus. Acceptable calculated orifice sizes and left ventricular--aortic (LV-Ao) pressure gradients may be obtained with the 23 mm. or larger prostheses. Actuarial survival curves show 92 percent of patients alive and well at 24 months' follow-up.  相似文献   

14.
Between February, 1983 and August, 1987, twelve children, aged from 2 years to 16 years, underwent aortic valve replacement associated with enlargement of aortic annulus successfully. According to the form of the left ventricular outflow tract obstruction, enlargement of aortic annulus was performed by Konno procedure in eight cases, by Nicks procedure in three cases and by Manouguian procedure in one case. In Manouguian procedure, mitral valve replacement associated with enlargement of mitral annulus was carried out simultaneously. In Konno and Manouguian procedures, the diameter of aortic annulus was enlarged from 180% to 200% compared with the original annular size, whereas in Nicks procedure, the diameter was enlarged around up to 110%. St. Jude Medical valve, of which size ranged from 21mm to 25mm, was employed in these procedures. All these children survived operation, and the post-operative follow up period ranged from 1 month to 55 months. There was one late death eleven months after Konno procedure because of respiratory failure resulting from pulmonary hypertension which persisted postoperatively. The remaining eleven children are surviving well after procedure. These results suggest that aortic valve replacement associated with enlargement of aortic annulus is an acceptable procedure in children with small aortic annulus or sub-aortic stenosis.  相似文献   

15.
From April, 1999 to November, 1999, 8 patients underwent the aortic valve replacement using Medtronic Freestyle aortic root bioprosthesis. Mean age was 67.8 years old. Aortic valve etiology was as follows, AS: 1 case, AR: 2 cases, ASR: 3 cases, IE: 1 case, mechanical valve malfunction due to subvalvular pannus: 1 case. The implanted valve size was 25: 2 cases, 23: 3 cases, 21: 1 cases, 19: 2 cases. Surgical technique was subcoronary: 7 cases, full-root: 1 case. Post-op 2D-echo revealed tribial aortic valve incompetence in two cases because of size discrepancy between the aortic annulus and the ascending aorta. Pacemaker implantation was needed in 1 case because of the complete A-V block. In comparison with 5 cases of aortic valve replacement with Hancock II performed in same period, there were no significant differences about the implanted valve size and mean systolic pressure gradient, but the effective orifice area in Freestyle cases was significantly larger than Hancock II cases.  相似文献   

16.
Objective This is a retrospective analysis of 94 patients who underwent aortic valve replacement for predominant aortic stenosis between January 1998 and December 2004. Patients and Methods Age ranged from 16 to 70 years (mean 43.2±13.2 years). 73 were male (77.7%). Etiology was rheumatic in 71 (75.5%) and degenerative in 23 (24.5%) patients. On transthoracic echocardiography, the diameter of the aortic annulus ranged from 19 mm to 36mm (mean 28.5±3.0 mm) and the peak systolic gradients ranged from 54 mm to 174 mm of Hg (mean of 109.8±28.8 mmHg). Aortic regurgitation was absent or mild in 76 patients (80.8%) and moderate in rest. A mechanical valve was implanted in 66 patients (70.2%) and a tissue valve in 28 patients (29.8%). Valves of size 23 mm or more were implanted in 75 patients (80%). A valve of 25 mm or larger was implanted in 55 patients (54.3%). Results There were no early deaths. Two patients required permanent pacemaker implantation for complete heart block in the immediate postoperative period. Prosthetic valve thrombosis in one patient was relieved by thrombolysis. Anticoagulant related hemorrhage was seen in two patients. One patient underwent homograft aortic valve replacement for prosthetic valve endocarditis nine months after surgery. Conclusion Isolated aortic valve replacement in patients with predominant aortic stenosis can be performed safely by implanting an adequately large sized prosthesis, without root enlargement in a large majority of patients.  相似文献   

17.
BACKGROUND: Paravalvular leakage is one of the most serious complications of aortic valve replacement in patients with aortitis syndrome. The purpose of this study was to compare the effectiveness of the intravalvular implantation technique in preventing paravalvular leakage with that of the conventional technique. METHODS: Since 1982, 14 patients with aortic regurgitation caused by aortitis syndrome have undergone aortic valve replacement at our institute. An intravalvular implantation technique was applied in 7 of the 14 patients. The technique consists of suturing a prosthetic valve to the aortic annulus and sandwiching the leaflets between exogenous felt pledgets and the inflamed aortic annulus. RESULTS: Paravalvular leakage occurred in 3 of 7 patients in the conventionally treated group and in none of 7 in the intravalvular implantation group. CONCLUSIONS: The intravalvular implantation technique is effective in preventing paravalvular leakage in patients with aortitis syndrome.  相似文献   

18.
Aortic valve replacement in adult patients with small aortic annuli   总被引:6,自引:0,他引:6  
Fifty-five patients with small aortic annuli underwent valve replacement either isolated or combined with other procedures. Patch enlargement of the aortic annulus in the area of the noncoronary sinus was used in 32 patients. The width of the patch was calculated by multiplying the desired increase in diameter by pi and adding 8 mm for suturing. The remaining 23 patients had aortic valve replacement with a prosthesis larger than the aortic annulus. The prosthesis was sutured in a supraannular position in the area corresponding to the noncoronary sinus. This slightly tilted position does not compromise function of Carpentier-Edwards or Bj?rk-Shiley prostheses. Prosthetic gradients ranged from 0 to 18 mm Hg (9.2 +/- 3.9 mm Hg) in patients with patch enlargement of the aortic annulus and from 0 to 22 mm Hg (7.2 +/- 5.8 mm Hg) in patients with supraannular aortic prostheses. Although these techniques allow for insertion of prosthetic valves only one and two sizes larger than the aortic annulus, they appear to be satisfactory in most adult patients with a small aortic annulus.  相似文献   

19.
We report transcatheter aortic valve implantation (TAVI) for pure aortic valve insufficiency in a patient with an otherwise normal aortic valve and a long-term left ventricular assist device (LVAD). An oversized 29-mm Edwards SAPIEN valve (Edwards Lifesciences, Irvine, CA) was implanted in the 21-mm native aortic valve annulus. Despite the complete absence of aortic calcifications, the prosthesis remained stably anchored inside the annulus. The reported experience demonstrates that TAVI is feasible even in patients with pure aortic valve regurgitation and can be a reasonable option in patients with aortic regurgitation after LVAD implantation.  相似文献   

20.
BACKGROUND: The aim of this study was to determine the durability of aortic valve preservation and root reconstruction in type A aortic dissection with involvement of the aortic root. METHODS: From November 1976 to February 1999, 246 patients underwent surgical treatment for acute type A aortic dissection at our institution. In 121 patients (49%), all with acute type A dissection and aortic root involvement, the aortic valve was preserved and one or more of the sinuses of Valsalva were reconstructed. The mean age of this group was 59 +/- 11 years and 70 (58%) were men. Thirty patients (25%) were operated in cardiogenic shock. Criteria for aortic root reconstruction were technical feasibility and surgeon preference. Techniques used for reconstruction were valve resuspension in all patients and additional reinforcement of the aortic root with Teflon (L.R. Bard, Tempe, AZ) felt (n = 21), gelatin-resorcinol-formaldehyde-glue (GRF-glue, Fii, Saint-Just-Malmont, France) (n = 103), or fibrinous glue (Tissu-col, Immuno AG, Vienna, Austria) (n = 5). Mean follow-up was 43.5 +/- 46 months. RESULTS: The operative mortality was 21.5% (n = 26). Actuarial survival was 72% +/- 4%, 64% +/- 5%, and 53% +/- 6% at 1, 5, and 10 years, respectively. Median aortic regurgitation in patients with retained native aortic valve at follow-up was 1+. All root reoperations included aortic valve replacement (n = 12). Freedom from aortic root reoperation was 95% +/- 2% at 1 year, 89% +/- 4% at 5 years, and 69% +/- 9% at 10 years. The incidence of aortic root reoperation was 23%, 11%, and 40%, respectively, when Teflon felt, GRF-glue, and fibrinous glue were used for root reconstruction. Multivariate Cox proportional hazard analysis revealed the use of fibrinous glue (RR = 8.7; p = 0.03) as well as the presence of an aortic valve annulus more than 27 mm (RR = 4.2; p = 0.04) as independent risk factors for aortic root reoperation. CONCLUSIONS: Aortic valve preservation in acute type A dissection provides relatively durable results. The use of fibrinous glue for root reconstruction seems to compromise the long-term durability of the repair compared with Teflon felt and GRF-glue. A dilated aortic annulus requires a more extensive root procedure.  相似文献   

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