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At least 451 records · Page 25Linked to original sources
PubMed2005

Feasibility of valve repair for regurgitant bicuspid aortic valves--an echocardiographic study.

BACKGROUND: There is increasing interest in the role of valve repair for patients with isolated severe aortic regurgitation. Those with bicuspid aortic valves are suggested as most suitable for repair. Morphologic features of these valves that suggest feasibility of repair are not well defined. METHODS: Perioperative echocardiograms on 132 consecutive patients (mean age 42 +/- 12 years; 94% male), with bicuspid valves and isolated aortic regurgitation undergoing surgery at our institution were reviewed. Seventy-five patients (57%) underwent successful valve repair. Repair was attempted but unsuccessful for another 8 patients (6 intraoperatively and 2 before discharge). RESULTS: Cusp prolapse was the most common primary mechanism of regurgitation (88 patients [67%]), with 81 patients having primarily eccentrically directed regurgitation. Echocardiographic examination of 72 (55%) had evidence of cusp thickening with 40 (30%) having cusp calcification. By multivariate analysis, an eccentric regurgitant jet direction (odds ratio = 14.3; 95% confidence interval [CI] = 3.4 to 59.6), lack of cusp thickening (odds ratio = 5.9 [1.7 to 20]), lack of cusp calcification (odds ratio = 4.2; [1.1 to 16.7]) and the absence of commissural thickening (odds ratio = 4.8 [1.3 to 16.7]) were independently associated with a greater likelihood of successful valve repair. Greater cusp thickening was the only factor associated with attempted but failed repair. CONCLUSIONS: Successful repair of regurgitant bicuspid aortic valves was more feasible for those patients with eccentric regurgitant jets, those without cusp or commissural thickening or cusp calcification. Recognition of these features may enhance patient selection and improve procedural outcomes with aortic valve repair.

Adult↗
PubMed1977

Radiopaque marker in the tilting disc of the Björk-Shiley heart valve. Evaluation of in vivo prosthetic valve function by cineradiography.

This paper describes a new, noninvasive method for evaluating the in vivo function of the Björk-Shiley tilting disc valve in the aortic, mitral, and tricuspid positions. The tilting disc was equipped with a ring-shaped radiopaque marker, which permits visualization of the motion of the disc by both cineradiographic and fluoroscopic studies. A beam direction corresponding to the axis of motion of the disc should be sought for calculation of the prosthetic opening angle, whereas prostehtic valve closure is demonstrated by a beam direction deviating 20 to 30 degrees from the valve ring plane. Complete opening to 60 degrees and closure of the prosthetic valve, indicating free motility of the tilting disc, were confirmed by cineradiograms. The error of estimation of the in vivo opening angle is small with deviations of less than 15 degrees from the ideal beam direction and negligible for opening angles approaching 60 degrees. Deviations in two planes simultaneously cause less error than deviation in one plane. The radiopaque marker was designed to detect mechanical valve failure owing to thrombotic obstruction. The incidence of this particular complication was 8.1 per 100 patient-years after aortic valve replacement without anticoagulation treatment. With anticoagulation, this incidence was zero after aortic and 2.5 after mitral valve replacement. In our clinical experience to date, which comprises over 1,250 implants, we have not encountered a single case of primary mechanical valve dysfunction. Our current program includes a change-over to the radiopaque tilting-disc model of the Björk-Shiley prosthesis, which was introduced at this clinic in March, 1975.

Aortic Valve↗
PubMed1996

The dual-switch valve. A new hydrostatic valve for the treatment of hydrocephalus.

The currently available hydrocephalus valves are still far from perfect. Whereas the design principles of differential pressure valves and adjustable devices involve the danger of overdrainage, hydrostatic valves have a tendency to clog. The new dual-switch valve (DSV) avoids overdrainage-related problems such as subdural hygromas/hematomas or slit-like ventricles with the high risk of proximal catheter obstruction by means of two parallel chambers in a titanium casing: one for the the horizontal and the other for the vertical position. The control chamber for the horizontal position is closed by a gravity-activated tantalum ball as soon as the patient moves into an upright position. Now the drainage of CSF is directed into the appropriate controller for the erect position. Thus, the hydrostatic differential pressure between ventricles and peritoneal cavity is counterbalanced and the intraventricular pressure (IVP) remains within physiological values independently of the CSF flow and the position of the patient. To avoid the problem of clogging, the newly designed valve introduces large-area diaphragms to create extensive acting forces. The forces generated in this way are able to overcome sticking forces set up as a result of high protein content or cellular debris. By this mechanism the IVP is maintained in physiological ranges regardless of the CSF composition. The new valve has been investigated with a computer controlled test apparatus especially designed to simulate different positions of the body. The in vitro test results according to ASTM standards document a superior performance in comparison with other valves. When the new device was interposed in external drainage systems precision of its function was confirmed even in the presence of elevated protein content and high CSF flow. Simulation of the upright position of the patient allowed documentation of the valve's reliability in maintaining the IVP within physiological ranges. A clinical trial with implantation of the new dual-switch valve was started at the beginning of 1995; so far follow up has been short. Clinical and computer tomographic monitoring has provided evidence of the valve's capacity to avoid the problems of overdrainage and early clogging.

Adult↗
PubMed1989

[The nasal valve area: structure, function, clinical aspects and treatment. Sulsenti's technic for correction of valve deformities].

The nasal valve and nasal valve area are two entities which should not be confused. The nasal valve area is the narrowest portion of the nasal passage. It is bounded: medially by the septum; superiorly and laterally by the caudal margin of the upper lateral cartilage and its fibro-adipose attachment to the pyriform aperture ('empty triangle'); inferiorly by the floor of the pyriform aperture. The nasal valve, on the other hand, is the specific slit-like segment between the caudal margin of the upper lateral cartilage and the septum. From a physiological and surgical point of view, this distinction is fundamental. The nasal valve area is the site of the highest nasal resistance. Therefore, small deformities of the valve area may severely impair the dynamics of nasal air flow. Rhinomanometry and nasal endoscopy permit the best definition of valve pathophysiology. After having discussed the various surgical techniques reported in the literature, the authors present an original technique for the surgical correction of valvular deformities. It is completely performed through Cottle's hemitransfixion incision. The technique has several advantages: a) performance of only one incision, sufficient to visualize the entire nasal valve and cartilaginous vault, thus minimizing the risk of scar tissue formation; b) through the space thus created it is possible not only to correct the entire septum, but also to inspect and easily reach the structures constituting the nasal valve area; c) it is possible to use various types of grafts to support or reconstruct the valve area; d) it is possible to reach the key area as well as to do lateral osteotomies: all variations in shape and position of the nasal pyramid may be performed in order to normalize direction and pressures of nasal air flow: e) through the retrograde undermining of the lower lateral cartilages the resistance of the cul-de-sacs may be optimally adjusted; f) it is possible to change the shape, size and position of the nostrils as well as to properly correct the columella and naso-labial angle. The technique, therefore, permits maximum correction of valvular deformities with the concomitant functional modification of any abnormalities of the nasal pyramid.

Adult↗
PubMed1980

Orifice-view aortography in patients with congenitally deformed aortic valves: determination of aortic valve area.

Orifice-view aortography is a contrast cineaortographic technique that allows en face viewing of the aortic valve. In this projection the anatomic configuration of the aortic valve is identified, and it is possible to planimeterize the visualized aortic valve opening and accurately determine the orifice area. Fifteen individuals with congenitally deformed aortic valves with gradients ranging from trivial (< 10 mm Hg) to surgically significant (6E 60 mm Hg) were subjected to aortic orifice area measurement by orifice-view aortography, and the area was compared with the peak systolic gradient and valve area. The results yielded a cloe correlation with the aortic valve area index as measured hydraulically or, as in three instances, directly from the surgically excised specimen (r = 0.94). A satisfactory correlation was also shown with the valve area index and the peak aortic valve gradient (r = 0.85). These observations indicate that orifice-view aortography is an accurate method for the measurement of the aortic valve orifice and may be particularly useful when hydraulic measurements are unattainable or invalid.

Adolescent↗
PubMed2006

Using cardiac magnetic resonance tomography for assessment of aortic valve area in aortic valve stenosis.

Calcified aortic valve stenosis (AS) is the most common valvular disease in the elderly population and constitutes a significant health and socioeconomic problem. Doppler echocardiography is the recommended diagnostic tool for the initial evaluation of AS. Transvalvular pressure gradients and aortic valve area have been used as quantitative parameters for grading the severity of AS, but the latter one is less susceptible to changes in flow dynamics and therefore considered the more independent and reliable parameter. The aortic valve area can be assessed directly by transesophageal echocardiography (TEE), which reflects the anatomic or geometric orifice area, or it can be calculated noninvasively by transthoracic echocardiography (TTE) using the continuity equation, or, invasively, by cardiac catheterization (CC) using the Gorlin formula, both reflecting the effective orifice area. Assessment of aortic valve area by TTE can be limited in some patients due to inadequate acoustic window. Similarly, TEE as a semi-invasive technique is not well tolerated by some patients and the planimetry is limited in patients with heavily calcified aortic valve leaflets. CC is an invasive procedure associated with a substantial risk of cerebral embolism and the Gorlin formula has been shown to be susceptible to changes in flow dynamics. Cardiac magnetic resonance tomography (CMR) is a new imaging technique capable of imaging the aortic valve with high resolution and has recently been used for assessment of the aortic valve area in AS. This review focuses on the feasibility of CMR for the assessment of aortic valve area in AS compared to current standard techniques and discusses some of the typical pitfalls and the sources for the discrepant results observed between the different techniques for assessment of the aortic valve area.

Aortic Valve↗
PubMedDate not supplied

Aortic valve morphology definition with transthoracic combined with transesophageal echocardiography in a population with high prevalence of bicuspid aortic valve.

OBJECTIVE: To assess the utility of transthoracic echocardiography (TTE) with second harmonic combined with transesophageal echocardiography (TEE) in defining aortic valve morphology in a subset of patients with a high prevalence of bicuspid aortic valve. METHODS AND MATERIALS: Patients (n = 174) with dilated aortic root were consecutively evaluated using, initially, TTE. The aortic valve structure was assigned as tricuspid, bicuspid or undefined. In those assigned as bicuspid or undefined, TEE was performed. Other factors that could affect valve morphology assignment were recorded and evaluated in multivariate analysis. RESULTS: TTE was able to characterise 89% of the tricuspid valves and 56% of the bicuspid. Bicuspid structure was the only variable that, in the multivariate analysis, was related to the inability to definitively assign aortic valve morphology (OR = 0.13). TEE was performed in 59 patients and the morphology was definitively assigned in 56 of them (95%). TEE diagnosed 15 bicuspid valves in addition to confirming the 17 identified by TTE. Overall, using TTE combined with TEE we were able to correctly assign valvular morphology in 98% of patients. CONCLUSION: In a subset of patients with a high prevalence of bicuspid aortic valve, combination of TTE and TEE should be considered to define aortic valve morphology. TEE identifies an important number of patients with BAV.

Aortic Valve↗
PubMed1991

Aortic valve replacement with omniscience and omnicarbon valves.

Clinical results achieved in 100 cases of aortic valve replacement with the Omniscience (O-S) valve during the period from 1980 to 1985 as well as 100 cases of aortic valve replacement with the Omnicarbon (O-C) valve during the period from 1985 to 1989 were studied. Concomitant surgical procedures including mitral valve replacement were performed in 63 patients in the O-S group and 67 patients in the O-C group. Cumulative follow-up in the two groups was carried out for a total of 559 and 273 patient-years, respectively. The overall 4-year actuarial survival rate was 82% +/- 3.8% in the O-S group and 89.5% +/- 3.2% in the O-C group, the corresponding rates for patients undergoing isolated aortic valve replacement being 82.9% +/- 4.2% in the O-S group and 91.9% +/- 3.5% in the O-C group. The overall 4-year actuarial event-free rate with respect to thromboembolic complications was 88.8% +/- 3.3% in the O-S group and 94.4% +/- 2.8% in the O-C group, as compared with the corresponding rates of 89.2% +/- 3.6% in the O-S group and 95.9% +/- 2.8% in the O-C group for patients undergoing isolated aortic valve replacement. The overall rate of valve-related complications, including thromboembolism, anticoagulant-related hemorrhage, perivalvular leak, infection, and structural failure, was 78.8% +/- 4.2% in the O-S group and 89.3% +/- 3.5% in the O-C group (p less than 0.05), and for isolated aortic valve replacement, 79.7% +/- 4.5% in the O-S group and 89.6% +/- 4.1% in the O-C group.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1995

Tissue engineering heart valves: valve leaflet replacement study in a lamb model.

BACKGROUND: Valve replacements using either bioprosthetic or mechanical valves have the disadvantage that these structures are unable to grow, repair, or remodel and are both thrombogenic and susceptible to infection. These characteristics have significantly limited their durability and longevity. In an attempt to begin to overcome these shortcomings, we have tested the feasibility of constructing heart valve leaflets in lambs by seeding a synthetic polyglycolic acid fiber matrix in vitro with fibroblasts and endothelial cells. METHODS: Mixed cell populations of endothelial cells and fibroblasts were isolated from explanted ovine arteries. Endothelial cells were selectively labeled with an acetylated low-density lipoprotein marker and separated from the fibroblasts using a fluorescent activated cell sorter. A synthetic biodegradable scaffold constructed from polyglycolic acid fibers was seeded with fibroblasts, which grew to form a tissue-like sheet. This tissue was subsequently seeded with endothelial cells, which formed a cellular monolayer coating around the leaflet. Using these constructs, autologous (n = 3) and allogenic (n = 4) tissue engineered leaflets were implanted in 7 animals. In each animal the right posterior leaflet of the pulmonary valve was resected and replaced with an engineered valve leaflet. RESULTS: All animals survived the procedure. Postoperative echocardiography demonstrated no evidence of stenosis and trivial pulmonary regurgitation in the autografts and moderate regurgitation in the allogenic valves. Collagen analysis of the constructs showed development of an extracellular matrix. Histologic evaluation of the constructs demonstrated appropriate cellular architecture. CONCLUSIONS: This preliminary experiment showed that a tissue engineered valve leaflet constructed from its cellular components can function in the pulmonary valve position. Tissue engineering of a heart valve leaflet is feasible, and these preliminary studies suggest that autograft tissue will probably be superior to allogenic tissue.

Animals↗
PubMed1982

In vitro closing behaviour of Björk-Shiley, St Jude and Hancock heart valve prostheses in relation to the in vivo recorded aortic valve closure.

To compare prosthetic valve behaviour with that of the natural aortic valve, experiments were performed in vitro as well as in vivo. In a mock circulation system, cinematographic high-speed recordings of the valvular behaviour were made for Björk-Shiley, St Jude and Hancock heart valve prostheses. Simultaneously with the film recording, the aortic flow and the left ventricular and aortic pressures were measured. The closing behaviour of the natural aortic valve was recorded in in vivo experiments following the same measuring technique. Comparison of the film frames with the aortic flow signal revealed that the mechanical prostheses mainly close due to the back flow in the early phase of diastole; they close only for 5% of their cross-sectional area during systolic ejection. The Hancock bioprosthesis closes already for 45% during the flow deceleration phase of systole, which is however significantly less than the corresponding closure of the aortic valve as recorded in vivo (74%). The change in fluid viscosity from 3.10(-3) Ns/m2 to 1.10(-3) Ns/m2 does not affect the closing behaviour of the mechanical prostheses. Reducing the peak value of systolic aortic flow by a factor two decreases the cross-sectional area of the prosthetic valves at peak systole. When the natural aortic valve closing mechanism is applied to a disc-valve prosthesis, a partial (30%) systolic valve closure is found.

Animals↗
PubMed2005

Three-dimensional in vivo characterization of calcification in native valves and in Freestyle versus homograft aortic valves.

OBJECTIVE: This article describes a novel interactive method for quantitative evaluation of calcium deposits in the aortic valve by means of electron beam tomography data fusion technique. METHODS: The technique relied on the use of hierarchic 3-dimensional free-form volume registration with fast global optimization between normally acquired and contrast-enhanced electron beam tomographic volume. A total of 66 contrast-enhanced electron beam tomographic scans of the aortic root were performed in 27 patients, 10 with native aortic valve disease (group A) and 17 from a prospective randomized trial of aortic root replacement (group B, 9 Freestyle grafts [Medtronic, Inc, Minneapolis, Minn] and 8 homografts). To validate the in vivo electron beam tomographic measurements, 5 patients from group A underwent electron beam tomographic scans before the operation and then had their own valves, explanted at the time of surgery, analyzed for calcium quantification by ex vivo electron beam tomography. RESULTS: In group A, the mean (+/- SE) calcification score was 6560 +/- 2388, which correlated with peak gradients measured at echocardiography ( r = 0.93, P = .02). In group B, the mean (+/- SE) calcification score was 168 +/- 27, showing a tendency toward a lower calcification for Freestyle valves than for homografts at 2 years after implantation ( P = .052). A mean variability of 6% was found between in vivo electron beam tomographic scores of calcification and those measured on valve specimens after explantation. CONCLUSION: We describe a novel method to characterize the degree and location of calcification in both native valves and postoperative valve implants. The technique may be useful in the management of patients with aortic valve disease and has potential as a screening tool for high-risk patients to diagnose early valve calcification and possibly institute corrective measures.

Aged↗
PubMed1977

Echocardiographic spectrum of mitral valve motion in children with and without mitral valve prolapse: the nature of false positive diagnosis.

To examine problems in echocardiographic diagnosis of mitral valve prolapse, multiple crystal cross-sectional echocardiography and single crystal recordings derived from the multiple crystal array were used to study 45 clinically normal children aged 3 to 15 years (Group A), 26 children aged 2 to 10 years with known mitral valve prolapse (Group B), 12 children with a catheterization-proved large left to right shunt at the ventricular level (Group C) and 8 children with catheterization-proved left ventricular outflow tract obstruction (Group D). Children in Groups A and B were not studied hemodynamically. Children in Groups C and D had no evidence of mitral valve prolapse on angiography and were studied echocardiographically to determine the effect of changes in ventricular shape on the patterns of mitral valve motion. In the real time cross-sectional studies, normal patients demonstrated a spectrum of mitral valve motion in which the bodies of the anterior and posterior leaflets became slightly horizontal with systolic ejection. The mitral apparatus assumed a curvilinear funnel shape. Arching of the leaflets into a horizontal configuration was more striking in the presence of either left ventricular dilatation in left to right shunt or involvement of the anterior mitral anulus in subaortic stenosis (two patients) and was associated with false positive M mode tracings suggesting mitral valve prolapse. This latter configuration was easily differentiated from the superior motion of the body of the leaflets in true prolapse. Studies of single crystal M mode recordings derived form the cross-sectional array in known locations from six normal patients revealed M mode patterns of pseudoprolapse in tracings derived from the leaflet body and patterns of normal motion at the free edge. In contrast, superior-posterior prolapse visualized in cross-sectional studies in patients with the click-murmur syndrome was associated with abnormal M mode recordings from all parts of the leaflet, including the free edge, although the abnormalities were most striking in tracings derived from the leaflet body. The M mode echocardiographic findings of mitral valve prolapse in both normal patients and patients with the click-murmur syndrome were dependent upon transducer angulation and the portion of the valve examined. The critical differentiation of the spectrum of normal valve motion from prolapse requires careful evaluation of echoes from the free edge of the leaflet where the posterior and anterior leaflet echoes coapt in early systole.

Adolescent↗
PubMed1998

Regression of left ventricular hypertrophy after aortic valve replacement for aortic stenosis with different valve substitutes.

OBJECTIVE: Stentless biologic aortic valves are less obstructive than stented biologic or mechanical valves. Their superior hemodynamic performances are expected to reflect in better regression of left ventricular hypertrophy. We compared the regression of left ventricular hypertrophy in 3 groups of patients undergoing aortic valve replacement for severe aortic stenosis. Group I (10 patients) received stentless biologic aortic valves, group II (10 patients) received stented biologic aortic valves, and group III (10 patients) received bileaflet mechanical aortic valves. METHODS: Echocardiographic evaluations were performed before the operation and after 1 year, and the results were compared with those of a control group. Left ventricular diameters and function, left ventricular wall thickness, and left ventricular mass were assessed by echocardiography. RESULTS: Group I patients had a significantly lower maximum and mean transprosthetic gradient than the other valve groups (P = .001). One year after operation there was a significant reduction in left ventricular mass for all patient groups (P < .01), but mass did not reach normal values (P = .05). Although the rate of regression in the interventricular septum and posterior wall thickness differed slightly among groups, their values at follow-up were comparable and still higher than control values (P = .002). The ratio between interventricular septum and posterior wall and the ratio between wall thickness and chamber radius did not change significantly at follow-up. CONCLUSIONS: Because the number of patients was relatively small, we could not use left ventricular mass regression after I year to distinguish among patients undergoing aortic valve replacement for aortic stenosis by means of valve prostheses with different hemodynamic performances.

Aged↗
PubMed1998

Cardiac valve endothelial cells: relevance in the long-term function of biologic valve prostheses.

OBJECTIVE: For reasons that are still unclear, biologic heart valve prostheses undergo degeneration after implantation. We studied the possible role of the immune system in this process. METHODS: We examined the expression of immunologically relevant molecules by human cardiac valve endothelium in situ and in vitro and studied re-endothelialization of implanted allogeneic and xenogeneic valvular surfaces using explanted bioprostheses and valves obtained from donor hearts at cardiac retransplantation. RESULTS: We demonstrate that human cardiac valve endothelial cells express molecules capable of initiating immune responses and might therefore play a role in the degeneration of viable cardiac valve prostheses. Also, we show evidence of re-endothelialization on the surfaces of xenografts and allografts but not on valves obtained from previously transplanted hearts. CONCLUSION: Inasmuch as valves from previously transplanted hearts seem to be free from degeneration, we conclude that reduction of the immunogenicity of allograft valve prostheses by HLA matching or immunosuppressive treatment might further improve long-term results after allograft valve replacement.

Antigens, CD↗
PubMed2000

Adhesion molecules in nonrheumatic aortic valve disease: endothelial expression, serum levels and effects of valve replacement.

OBJECTIVES: We studied the expression of intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1) and endothelial selectin (E-selectin) on aortic valve endothelium in patients undergoing valve replacement. We also assessed the relation between serum levels and endothelial expression and also the changes in serum levels following surgery. BACKGROUND: Nonrheumatic aortic valve disease is believed to be a degenerative condition. Increased tissue and soluble adhesion molecule levels are described in inflammatory conditions. METHODS: Aortic valves from 22 surgical (16 bicuspid, 6 tricuspid) and 6 autopsy (4 normal, 2 thickened) cases were studied by immunohistochemistry. Soluble adhesion molecules were measured in peripheral blood preoperatively, and at 6 and 18 months postoperatively, and compared with controls. RESULTS: The majority of the surgically removed tricuspid and bicuspid valves expressed adhesion molecules (E-selectin, 75% and 100%; ICAM-1, 75% and 80%; VCAM-1, 69% and 60%, respectively). The normal postmortem valves did not express these, while the diseased ones did. Endothelial expression of E-selectin correlated strongly with serum levels (r = 0.695, p = 0.004). Soluble E-selectin levels were significantly higher at baseline compared with controls (p = 0.017) and fell significantly at 18 months postoperatively (p = 0.005). CONCLUSIONS: Adhesion molecule expression on diseased valves supports an inflammatory component in "degenerative" aortic valve disease. The diseased valves may be the main source of elevated soluble E-selectin in this condition as blood levels correlate with endothelial expression and blood levels fall at 18 months postoperatively.

Aged↗
PubMed1998

[Aortic valve insufficiency in aneurysms of the ascending aorta: functional results following valve-sparing reconstruction].

BACKGROUND AND OBJECTIVE: Changes in geometry of the aortic root, especially a dilatation of the sinotubular junction, are the major causes of aortic valve regurgitation in ascending aortic aneurysm. In valves without structural defect, a valve sparing aortic root reconstruction may be a therapeutic option. Aim of this study was the assessment of functional results, in the early postoperative, and during follow-up, in a large patient cohort from one centre. PATIENTS AND METHODS: Between July 1993 and March 1998, a total of 48 valve sparing operations were performed at Hannover Medical School. Mean age of patients (34 males, 14 females) was 47.4 +/- 19 years. In a prospective design clinical, and echocardiographic examinations were performed pre-, intra and early postoperatively as well as 3.6 and then every 12 months during follow-up. Structural valve changes, systolic pressure gradients as well as the degree of diastolic regurgitation were evaluated. RESULTS: Aortic root reconstruction was successful in all patients; none died perioperatively. Extension of the underlying disease to the aortic arch was present in eleven, acute and chronic dissection of the ascending aorta (type A) in two and three patients, respectively. Echocardiographic follow-up over a mean period of 25.1 +/- 18.3 months (cumulatively 1204 months) revealed stable valve function in 41 patients without (n = 30) or with a minimal (n = 11) regurgitation. In three patients moderate valve regurgitation (grade 2) was observed, three patients (6.3%) had to be reoperated because of a progressive valve failure. Thromboembolic or bleeding complications were not observed. CONCLUSIONS: Valve sparing aortic root reconstruction is a promising alternative to the composite replacement of the ascending aorta. Low perioperative morbidity and mortality rates as well as favourable functional results were demonstrated. Long-term anticoagulation can be avoided. Long-term follow-up will be necessary to assess the definitive role of this new surgical approach.

Adult↗
PubMed2006

Role of human valve interstitial cells in valve calcification and their response to atorvastatin.

BACKGROUND: Calcific aortic valve stenosis is a common disease in the elderly and is characterized by progressive calcification and fibrous thickening of the valve, but the cellular and molecular mechanisms are not fully understood. We hypothesized that human valve interstitial cells (ICs) are able to differentiate into osteoblast-like cells through the influence of defined mediators and that this process can be modulated pharmacologically. METHODS AND RESULTS: To test this hypothesis, we treated primary cultures of human aortic valve ICs with osteogenic media, bone morphogenic proteins ([BMPs] BMP-2, BMP-4, and BMP-7), and tissue growth factor-beta ([TGF-beta] TGF-beta1 and TGF-beta3) for 21 days. These mediators induced osteoblast differentiation of valve ICs by significantly increasing the activity and expression of alkaline phosphatase ([ALP] P<0.001). A cytokine protein array revealed that atorvastatin treatment (100 micromol/L) of human valve ICs caused a downregulation in levels of expression of BMP-2, BMP-6, TGF-beta1, and TGF-beta3 after 24 hours. In addition, human valve ICs treated with atorvastatin in the presence of osteogenic media showed a significant reduction in ALP activity in comparison to cells treated with osteogenic media only (P=<0.001). This was further confirmed with immunocytochemical staining of valve ICs, whereby atorvastatin markedly reduced the expression of ALP and osteocalcin induced by osteogenic media in comparison to untreated cells. CONCLUSIONS: These findings suggest that human valve ICs are capable of osteoblastic differentiation, by potential mediators which can be pharmacologically targeted by atorvastatin.

Aged↗
PubMed1983

Biochemical analysis and electron microscopy of human mitral valve collagen in patients with various etiologies of mitral valve diseases.

Biochemical analyses and electron microscopy of mitral valve collagen were carried out in 29 patients with various mitral valve diseases. They were divided into 3 groups: (1) rheumatic heart disease (15 patients), (2) isolated rupture of chordae tendineae (8 patients), and (3) floppy mitral valve (6 patients). Normal mitral valves obtained at necropsy from 6 patients who died from extracardiac causes were used for control observations. Results of the electrophoretic analysis of the collagen of normal and diseased valves showed that all valves contained collagen types I, III, and AB collagen with similar electrophoretic patterns. Electron microscopic observations and comparisons of the segment-long-spacing crystallites of each type of collagen revealed similar band patterns, irrespective of the normal or diseased valves sources. It is concluded that the composition and primary molecular structure of mitral valve collagen are usually not altered in a wide variety of disease processes affecting the mitral valve.

Adolescent↗