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91.
Y. Misawa T. Saito H. Konishi S. Oki Y. Kaminishi K. Aizawa H. Takahashi O. Kamisawa M. Kato K. Fuse 《Journal of artificial organs》2002,5(3):0184-0187
We discuss the usefulness of the Cosgrove-Edwards ring from our early clinical results from 25 rings in 24 patients who underwent
mitral annuloplasty (MAP) or tricuspid annuloplasty (TAP) between June 1999 and December 2000. In the MAP group, the posterior
mitral annulus between the anterior and posterior fibrous trigones was reinforced with the prosthetic ring. In the TAP group,
the annuli of the anterior and posterior leaflets were splinted with the ring. The prosthetic ring was attached by pledgeted
U-sutures. Cardiologists performed echocardiography pre- and postoperatively. Thirteen of the 14 in the MAP group showed mitral
valve regurgitation of grade 0 or I. Six of the 11 in the TAP group showed tricuspid regurgitation of grade 0 or I, and 5
patients with regurgitation equal to or greater than grade II who remained in atrial fibrillation postoperatively recovered
without further clinical symptoms. No patient has required reoperation during a follow-up period of up to 2 years. Cosgrove-Edwards
ring-related complications, such as valve stenosis, ring detachment, and arrhythmia, have been not recognized in these patients.
In conclusion, for mitral and tricuspid annuloplasty, the Cosgrove-Edwards prosthetic ring showed excellent early clinical
results, particularly in patients maintained in sinus rhythm.
Received: November 5, 2001 / Accepted: May 30, 2002
Correspondence to:Y. Misawa 相似文献
92.
93.
目的 观测家猪心脏三尖瓣复合体 ,为家猪心脏研究和心脏移植积累资料。方法 甲醛固定的家猪心脏 35例 ,大体解剖并观测三尖瓣复合体。结果 家猪心脏三尖瓣复合体由瓣环、瓣膜、腱索和乳头肌构成 ,瓣环周长为 70 75± 8 4 5mm ,前瓣、后瓣、隔侧瓣、前隔连合、前后连合、后隔连合的高度分别为 14 5 8±2 6 4、14 16± 2 5 0、12 84± 2 37、6 2 9± 1 97、6 86± 1 0 1、6 5 1± 1 36mm。前隔连合、前后连合、后隔连合的宽度分别为 6 4 0± 1 5 4、6 78± 1 2 3、6 4 3± 1 4 6 ;前乳头肌起始 ,腱索附着于前瓣、后瓣和前后连合的条数分别为 3 0 0± 0 97、3 0 9± 1 0 9、2 4 4± 1 16 ;后乳肌起始 ,腱索附着于后瓣、隔侧瓣和后隔连合的条数分别为 2 6 0± 0 6 9、3 0 9± 1 6 3、1 14± 0 4 3。隔侧乳头肌起始 ,附着于前瓣、隔侧瓣、前隔连合的腱索条数分别为1 71± 0 6 7、2 37± 1 2 6、0 94± 0 4 2。结论 家猪心脏三尖瓣复合体中各结构与人类相似 ,但大小有一定差异。 相似文献
94.
Shigemitsu Iwai MD Kei Torikai MD Chris M. Coppin MD Yoshiki Sawa MD 《Journal of artificial organs》2007,10(1):29-35
Currently used bioprosthetic valves have several limitations such as calcification and functional deterioration, and revitalization
through cellular ingrowth is impossible. To overcome these obstacles, we have developed a minimally immunogenic tissue-engineered
valve that consists of an unfixed, decellularized porcine valve scaffold capable of being spontaneously revitalized in vivo
after implantation. Porcine aortic root tissue was decellularized using detergents such as sodium lauryl sulfate and Triton
X-100. The porcine valve was treated very gently and plenty of time was allowed for constituents to diffuse in and out of
the matrix. In a preliminary study, a piece of decellularized porcine valve tissue was implanted into the rat subdermal space
for 14 and 60 days and the structural integrity and calcification were evaluated. As an in vivo valve replacement model, the
decellularized porcine valve was implanted in the pulmonary valve position in dogs and functional and histological evaluation
was performed after 1, 2, and 6 months. Histological examination showed that the newly developed detergent treatment effectively
removed cellular debris from the porcine aortic tissue. Decellularized porcine valve tissue implanted subdermally in rats
showed minimal inflammatory cell infiltration and calcification. In the valve replacement model, spontaneous reendothelialization
and repopulation of the medial cells were observed within 2 months, and good valve function without regurgitation was observed
by echocardiography up to 6 months. The minimally immunogenic decellularized porcine valve proved effective in mitigating
postimplant calcification and provided a suitable matrix for revitalizing prostheses through in situ recellularization, cellular
ingrowth, and tissue remodeling. 相似文献
95.
Jagdish Butany Manmeet S. Ahluwalia Craig Munroe Cristina Fayet Christina Ahn Patrick Blit Charis Kepron Roberto J. Cusimano Richard L. Leask 《Cardiovascular pathology》2003,12(6):322-344
Mechanical heart value prostheses have been in use since the 1950s. Many prostheses have been used for a while and then discontinued. Today, there are a large number and variety of prostheses in use and an even larger variety that are in place in patients. These may be explanted at any time for a number of reasons. It is essential for the practicing pathologist to be able to identify the prosthesis and be aware of some of its reported complications and modes of failure. This article, and a second one on bioprosthetic heart valves, is designed as a ready reference guide to heart valve prostheses, their important identifying features, their common complications, and modes of failure. It should help in the accurate identification of explanted prosthetic valves and more definitive reports. This accuracy of identification as well as tracking of abnormalities noted will, we hope, permit the identification of new failure modes and the recording of causes of failure of new (or even modified) prosthetic heart valves. 相似文献
96.
A case with tumorous deformity of the posterior mitral valve leaflet after spontaneous chordal rupture in a child is described. A partial rupture in the chordae tendineae of the posterior mitral leaflet was found by echocardiography in a 9-year-old Japanese boy. Tumorous bulging was gradually developed in the leaflet and was surgically excised 5 years later. Multiple nodular tumors were found on the atrial surface of the posterior mitral leaflet. Histological examination revealed that the tumorous bulging consisted of myxomatous materials in which collagen fibrils and very fine elastic fibers were distributed loosely and irregularly. Normal-looking endothelial cells covered the luminal surface of the bulging lesion. Vimentin-positive spindle-shaped mesenchymal cells were scattered in the bulge area. The labeling index of proliferating cell nuclear antigen (PCNA) in these cells was 29.3%. These spindle cells were positive for matrix metalloproteinase (MMP)-1 in the entire bulge area. The cells and matrix were positive for MMP-2 and tissue inhibitor of MMP (TIMP)-1 in the basal area of bulging, but were weakly positive or negative at the surface area. Reactivity for TIMP-2 in the cells in the bulge area was obviously weaker than that in the cells at the spongiosa of the anterior mitral leaflet, which was obtained from the patient at the valve replacement operation 9 months after the initial operation. These findings indicated that the tumorous deformity of the mitral valve was formed by the overgrowth of valve tissue under the stimulation of mitral regurgitation in this child, and the imbalance of MMP and TIMP might play an important role in the bulge formation. 相似文献
97.
David W. Barbara William D. Edwards Heidi M. Connolly Joseph A. Dearani 《Cardiovascular pathology》2008,17(3):166-171
BACKGROUND: Ebstein's anomaly has been described extensively in autopsy material. However, there have been no large surgical pathology series of this malformation. OBJECTIVE: To review clinical and surgical pathologic features of a large number of cases of Ebstein's anomaly from a single institution. METHODS: Review of medical histories, surgical reports, and surgical pathology reports at the Mayo Clinic (2000-2005). RESULTS: Among 104 patients, the mean age was 31 years (2 months-79 years), and 57% were female. Common ECG abnormalities included right bundle branch block (58%), first-degree heart block (31%), preexcitation (18%), and nonspecific intraventricular conduction delay/block (15%). Moreover, 74% had inter-atrial communication, 13% mitral valve prolapse, and 5% bicuspid aortic valve. Clinically, all had tricuspid regurgitation (severe in 74%), and 17% of anterior leaflets were fenestrated. No tricuspid valve was calcified. Surgically, tricuspid tissue was removed during replacement in 99% and repair in 1%. The anterior tricuspid leaflet was resected in 98%, and its length was 0.81-9.3 cm/m2 body surface area (mean, 3.3). Characteristically, leaflets were large and had irregular shapes and numerous short cordal or direct myocardial insertions. One tricuspid valve had two papillary fibroelastomas. None had clinical or pathologic evidence of active or healed endocarditis. CONCLUSIONS: Among patients with Ebstein's malformation, tricuspid valve tissue almost exclusively was removed during valve replacement and represented the anterior leaflet. Valve tissue was generally large, irregularly shaped, and associated with insertion of short cords or myocardial stumps. Interestingly, although appreciably deformed, Ebstein valves were not associated with infective endocarditis. 相似文献
98.
Toshinosuke Akutsu Ryota Imai Jun Saito Tomoyuki Suzuki 《Journal of artificial organs》2008,11(2):67-74
The Jyros (JR) valve and the newer On-X and MIRA valves, all installed antianatomically, were compared with the St. Jude Medical (SJM) valve in the mitral position to study the effects of valve design differences on the down-stream flow field and the associated valve closing sound. The dynamic particle image velocimetry method utilizing a high-speed video flow visualization technique was used to map the velocity field, and wavelet analysis of the sound was used to find the correlation between the ventricular flow field and the valve closing sound. Based on the experimental data, the following general conclusions can be made. In the velocity field directly below the mitral valve, where the distinct characteristic differences of the valve designs will be evident, twin symmetrical circulations were observed due to the divergent nature of the flow generated by the two inclined half-disks with the valve installed in the anti-anatomical orientation; the SJM, the On-X, and the MIRA valves generated a centrally downward circulation that opposed the valve leaflet closing movement, and resulted in relatively loud valve closing sounds. 相似文献
99.
Dynamic particle image velocimetry (PIV) was applied to the study of the flow field associated with prosthetic heart valves.
The results were compared with those of laser Doppler anemometry (LDA). Anatomically and antianatomically oriented Jyros (JR)
and St. Jude Medical (SJM) valves were compared in the mitral position to study the effects of valve design on the downstream
flow field. The experimental program used a dynamic PIV system utilizing high-speed, high-resolution video to map the true
time-resolved velocity field inside the simulated ventricle. This system was complemented by a study using the more traditional
LDA system for comparison. Based on the experimental data, the following general conclusions can be made. High-resolution
dynamic PIV can capture true chronological changes in the velocity and turbulence fields. It also produces very detailed velocity
and turbulence information comparable to the LDA results. In the vertical measuring plane that passes both the center of the
aortic and mitral valves (A-A section), the two valves (the SJM and the JR) show distinct circulatory flow patterns when the
valve is installed in the antianatomical orientation. Small differences in valve design can generate noticeable differences,
particularly during the accelerating flow phase. The SJM valve maintains a relatively high velocity through the central orifice;
the curved leaflets of the JR valve generate higher velocities with a divergent flow during the accelerating and peak flow
phases. In the velocity field directly below the mitral valve and normal to the previous measuring plane (B-B section), where
characteristic differences in valve design will be visible, symmetrical twin circulations were observed because of the divergent
nature of the flow generated by the two inclined half-disks installed in the antianatomical orientation. The SJM valve, with
a central downward flow near the valve, is contrasted with the JR valve, which has a peripheral downward circulation with
higher, turbulent stresses. 相似文献
100.
Gerola LR Wafae N Vieira MC Juliano Y Smith R Prates JC 《Surgical and radiologic anatomy : SRA》2001,23(3):149-153
We performed an anatomic study of the right atrioventricular valve in children under one year of age using a conservative method of dissection of the heart valve. The main aspects studied were the number of cusps and their morphometric characteristics, such as the width of the base and the depth of the cusps. Other parameters studied were the number of papillary muscles, number of tendinous cords, and diameter of the fibrous ring and the last one were divided in three regions, anterior, posterior and septal for localization of cusps. Our results showed that the number of cusps varied from two to four. Three cusps was the commonest finding and the fourth cusp, if present, was classified as anterolateral in location. The anterior and septal cusps had bases bigger than those of the posterior and anterolateral cusps; the septal cusp was deeper than the others; and the number of tendinous cords was greater for the anterior and septal cusps than for the posterior and anterolateral cusps. In addition, the posterior region showed great variability: in 35.7% it was occupied by undeveloped valve tissue and the posterior valve in these cases was located anteriorly. 相似文献