Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Valves”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 793 records · Page 44Linked to original sources
PubMed1990

[Post-operative evaluation of a 17 mm diameter Björk-Shiley Monostrut prosthesis for aortic valve replacement--pressure gradient and effective valve area].

A 17 mm diameter Björk-Shiley Monostrut prosthesis was implanted in a 64-year-old female for aortic valve replacement in a semi-emergency. This valve was one of the smallest valves which were available in Japan. The patient was admitted because of severe hemolytic anemia and heart failure. Echocardiography showed regurgitation and calcification of Ionescu-Shiley tissue valve which was implanted 5 years ago. The patient's body surface area was 1.2 m2. Because of narrow aortic annulus, we could barely implant a 17 mm diameter Björk-Shiley Monostrut prosthesis. The valve function was examined by Brockenbrough method. During catheterization, the heart rate was 85 b/min and cardiac index was 3.00 l/min/m2. In these hemodynamic conditions, simultaneous measurements of aortic and left ventricular pressures revealed only 9 mmHg mean systolic pressure gradient. Similarly, 20 mmHg of pressure gradient across the implanted valve was obtained by Gorlin's formula. We could calculate that the effective orifice area of a 17 mm diameter Björk-Shiley Monostrut prosthesis was 1.0 cm2. Postoperative echocardiography demonstrated 42 mmHg systolic pressure gradient across this prosthesis by Doppler techniques, and left ventricular wall thickness was not decreased. To best our knowledges, this was the first case in which post-operative evaluation such a small prosthesis was measured.

Aortic Valve↗
PubMed1988

Three-dimensional visualization of velocity profiles in the ascending aorta in humans. A comparative study among normal aortic valves, St. Jude Medical and Starr-Edwards Silastic Ball valves.

Blood velocities were recorded intraoperatively in the ascending aorta approximately 6 cm downstream of the aortic annulus in eight patients with normal aortic valves (prior to coronary bypass surgery) and in seven patients after implantation of a St. Jude Medical valve (4) or Starr-Edwards Silastic Ball valve (3) in the aortic position by means of constant temperature hot-film anemometry. The velocities were measured during 5-15 heart cycles at 41 predetermined measurement points almost evenly distributed in the cross sectional area. Velocity profiles were visualized three-dimensionally at 100 time intervals during one mean heart cycle. The standard deviation of velocities was correspondingly three-dimensionally visualized. For the patients with normal aortic valves the velocity profiles were generally flat but skew, with the highest velocity closer to the left vessel wall at the start of systole. During systole the skewness turned counter-clockwise with the highest velocities closer to the posterior, right and finally anterior vessel wall at the end of systole. In patients with an artificial heart valve in the aortic position the design of the valve was reflected on the contour of the profiles. The findings correspond well with model studies.

Adult↗
PubMedDate not supplied

Aortic valve replacement with a subcoronary ball valve--early experiments.

Between the years 1954 and 1958, the combined effort of a surgeon and an engineer allowed the development of some of the principles of aortic valve construction that proved clinically successful several years later. It was demonstrated for the first time that there was adequate room in the area of the sinuses of Valsalva below the coronary arteries for a prosthetic ball valve, and that such a ball valve did not obstruct flow. Aortic pulse tracings with such a ball valve in place were indistinguishable from those with the natural valve. Finally, the principle of the cloth sewing ring was utilized for suturing the valve in place.

Alabama↗
PubMed1984

[Plastic surgery of the mitral valve in mitral valve insufficiency - advantages of physiologic surgery].

Nine patients (mean age at the time of surgery 54.5 +/- 0.7 years), who had mitral valve reconstruction for mitral valve insufficiency were studied on an average of 15.0 +/- 7.5 months after the operation using technetium-99m-pertechnetate--or gold scintigraphy. The radionuclid ventriculograms were performed with the patient in RAO-position at rest and during mild exercise (50 watt). Looking at the results of the preoperatively performed heart catheterization with contrast ventriculography our datas showed a postoperative improved left ventricular function as well as a physiologic function of the mitral valve. Clinically the patients improved from class 3.6 to 1.6 (NYHA) on an average. The reconstructive mitral valve insufficiency is able to restore normal left ventricular function. The operation should be carried out on patients graded at class II (NYHA). Technetium-99m-pertechnetate scintigraphy (first pass technique) appears to be particularly suitable for evaluating left ventricular function and the function of the mitral valve after reconstructive mitral valve surgery.

Female↗
PubMed1983

[Evaluation of Hancock mitral valve by M-mode echocardiography. Clinical significance of the timing of closing and opening of the valve].

The valve function of a Hancock xenograft in the mitral position was evaluated by M-mode echocardiograms guided by the two-dimensional echocardiogram. From M-mode echocardiograms, the intervals from the second heart sound to mitral valve opening (II-MVo) and from the Q wave to mitral valve closure (Q-MVc) were measured in 24 patients with a Hancock xenograft, 16 with mitral stenosis (MS) and 20 normal controls. Twenty-four patients with a Hancock xenograft were divided into four groups according to the echocardiographic pattern of the xenograft. Fourteen with normal echocardiograms (I: N.P.), five with delayed opening of cusps from 20 to 90 msec (II: D.O.), three with a coarse fluttering of cusps in diastole (III: D.F.), and two with an obstructed prosthesis (IV: O.P.). The valve function of groups II and III was clinically normal. This suggests that a coarse fluttering of cusps and delayed opening of cusps do not always indicate malfunction of the Hancock xenograft. M-mode echocardiograms of group IV showed an increased thickening of cusps, multiple dense echoes between valve stents and a lack of a clear E point. The beat-to-beat variations of Q-MVc and II-MVo intervals showed no significant differences among patients with the Hancock xenograft, MS and normal controls. A small time-dependent variation of Q-MVc and II-MVo intervals observed in patients with the Hancock xenograft did not seem to interfere the reliable reproducibility of these intervals. In group I, II-MVo interval was 104 +/- 8 msec (mean +/- S.E.), which was significantly longer than that of normal controls (54.5 +/- 2.5 msec) (p less than 0.005). In groups II and III, II-MVo interval was almost equal to that of group I, but in two of group IV, this interval was 20 and 30 msec, respectively which was markedly shortened. Q-MVc intervals did not show significant differences among groups I, II, III and IV. There were significant differences in Q-MVc interval among patients with MS and the Hancock xenograft and normal controls. II-MVo interval of group I was inversely correlated with mean diastolic posterior wall velocity (MDPWV), stroke index (SI) and delta ejection time (ET), but significantly correlated with delta preejection period (PEP) and PEP/ET. However, there was no significant relationship between II-MVo interval and pulmonary capillary wedge pressure. This suggested that prolonged II-MVo interval reflects postoperative left ventricular dysfunction. In conclusion, to evaluate the function of a Hancock xenograft, echocardiograms of valve cusps and measurement of II-MVo interval have useful clinical significance.

Bioprosthesis↗
PubMed1981

Translocation of the aortic valve for prosthetic valve endocarditis.

Aortic prosthetic valve endocarditis is frequently associated with a perivalvular ring abscess which destroys the normal annulus, so that it is difficult to seat a new prosthesis. Between November, 1974, and January, 1980, we treated four patients with aortic prosthetic endocarditis by translocation of the aortic valve, closure of the native coronary artery ostia, and placement of saphenous vein bypass grafts to the coronary arteries. In each case operation was undertaken because of progressive congestive heart failure resulting from aortic regurgitation; two patients had systemic emboli, and two patients had uncontrolled infection. Infection was due to Enterococcus in three instances and to an unknown organism in one. Total ischemic times averaged 2 hours, 15 minutes; a 25 mm Dacron graft containing a porcine valve was used to replace the ascending aorta and aortic valve, and two or three saphenous vein grafts were placed to distal coronary arteries. One patient died 40 days postoperatively of renal failure and Pseudomonas pneumonia with an intact repair. The other three patients were hospital survivors, with one doing well until dying of chronic active hepatitis 12 months postoperatively. The other two patients are alive at 4 months and 18 months with satisfactory hemodynamic function and are free of infection. Translocation of the aortic valve for prosthetic valve endocarditis is a useful alternative when conventional replacement techniques cannot be utilized.

Adult↗
PubMed1995

[Re-replacement of Starr-Edwards mitral valve (model 6320) for prosthetic valve endocarditis 22 years after replacement].

The patient was a 43-year-old woman who had undergone mitral valve replacement with Starr-Edwards ball valve (model 6320) 22 years ago. Perivalvular mitral leakage due to prosthetic valve endocarditis and tricuspid regurgitation were found. She underwent re-replacement of the mitral valve. The operative findings revealed almost intact valvular function of the ball valve. As far as we know, 22 years is the longest follow-up for the Starr-Edwards ball valve which has maintained normal function.

Adult↗
PubMed1996

[Jaundice, anemia and mitral valve insufficiency following mitral valve reconstruction].

A 33-year-old man was admitted because of jaundice. Five months ago a reconstruction of the mitral valve was performed because of mitral valve insufficiency. There was a history of heroin dependence until three years ago. Laboratory tests showed normochromic normocytic anemia, increased nonconjugated serum bilirubin, decreased plasma haptoglobin, hemoglobinuria and hemosiderinuria. The peripheral blood smear contained numerous fragmented red cells, and the bone marrow showed a markedly increased erythropoiesis and absent iron stores. The clinical examination as well as echocardiography revealed severe mitral valve insufficiency; therefore, a mitral valve replacement was performed. Introperatively the mitral valve showed ruptured chordae tendineae of the posterior leaflet and a leaking stitch of the anterior leaflet. We diagnosed a macrovascular hemolytic anemia with subsequent mechanical injury and fragmentation of red cells on a dysfunctioning mitral valve.

Adult↗
PubMed1998

Optimisation of a stentless valve prosthesis based on an analytic parametric model of the aortic valve.

An analytical mathematical model of a stentless aortic valve has been implemented. The valve is characterised by a trileaflet geometry, cylindrical leaflets; the aortic root is schematised by a conical surface which includes the leaflet attachments. The model is defined through six geometric parameters: the base radius, the valve height, the commissure radius, the leaflet radial, circumferential and attachment line lengths. Five performance indexes have been used to optimise the valve geometry, namely: the systolic area, the leaflet circumferential stress in diastole, the leaflet bending strain in systole and two bending angles related to the rotation of the leaflets from the diastolic to the systolic configuration. The sensitivity analysis is carried out which can identify the influence of each geometric parameter on the performance indexes adopted for the optimum valve design. The analysis of the results provides the geometric configuration which optimises the overall function of the valve throughout the cardiac cycle.

Aortic Valve↗
PubMed1998

Aortic and mitral valve replacement in an 83-year-old female. 3 years follow-up of 16 mm bileaflet valve at the aortic position.

An 83-year-old female with aortic and mitral stenosis showed orthopnea. The aortic valve pressure gradient was 139 mmHg. The mitral valve orifice was 0.92-1.05 cm2 and the right ventricular pressure was 70 mmHg. The body surface area of the patient was 1.23 m2. Double valve replacement was performed with 16 mm CarboMedics pediatric bileaflet valve for the aortic position and 25 mm CarboMedics mitral valve for the mitral position. The patient leads a normal daily life with NYHA class II three years after surgery.

Aged↗
PubMed2000

Transesophageal echocardiographic (TEE) evaluation of the aortic valve, left ventricular outflow tract, and pulmonic valve.

The most important role of TEE in aortic valve disease is in the diagnosis of endocarditis and its complications. Examination of the annulus and subvalvular region is essential in any patient with possible aortic valve endocarditis. Assessment of the severity of aortic stenosis is a useful application of TEE when other data are either inconsistent or unavailable. TEE can provide a diagnosis of the origin of acute severe aortic insufficiency; this information may play a critical role in surgical planning. The diagnosis of a variety of aortic valve diseases can be made when TEE is performed to find an embolic source or to rule out dissection. In the case of mass lesions, such as papillary fibroelastomas and Libman-Sacks vegetations, the results of TEE carry major therapeutic implications. TEE offers generally excellent quality images of the LVOT and images of the RVOT and pulmonic valve that are superior to transthoracic echocardiography. The major clinical usefulness of TEE stems from its ability to identify pulmonic valve mass lesions and the causes of left and right ventricular outflow obstruction. TEE is also an important adjunct in the surgical management of left ventricular outflow obstruction.

Aortic Valve↗
PubMed2005

[Valve replacement with the Omnicarbon valve prosthesis. A 10-year follow-up].

OBJECTIVE: We retrospectively examined the outcomes of 264 patients who underwent consecutive Omnicarbon valve implantation surgery between April 1985 and May 1995. METHODS: At the time of surgery, patients who received this mechanical prosthesis averaged 57+/-11 years of age. Omnicarbon valves were placed in the aortic position in 36% of the cases, in the mitral position in 44%, and in both positions in 20%. Follow-up was carefully performed, with most patients undergoing physical examination at our clinic. While taking the case history, cardiac physicians specifically questioned the patient about valve-related complications. RESULTS: Accumulated total patient-years is 1291, with a mean follow-up time of 5.4 years. Survival at 10 years is 79.4+/-3.9%, including all causes of death and early mortality. Complications recorded during the 11-year study include: thromboembolism (0.1%), hemorrhage (0.4%), endocarditis (0.2%), and nonstructural failure (1.2%). No hemolytic anemia, valve thrombosis, or structural failure was detected during this long-term experience. Functional capability of these patients was subjectively assessed by the NYHA classification system. With follow-up time averaging over 5 years, 97% of our Omnicarbon valve patients are in NYHA I or II. CONCLUSION: The Omnicarbon mechanical prosthesis provides a good clinical performance for up to 10 years in both the aortic and mitral positions. Results indicated a low incidence of thromboembolism and of hemorrhagic complications.

Adult↗
PubMed2006

[Clinical outcome of aortic valve replacement with 19-mm prosthetic valve in elderly patients].

From 1979 to June 2005, 90 patients aged 65 or older underwent aortic valve replacement with 19-mm prosthetic valve. They were 84 women and 6 men, with a mean age of 74. The mean body surface area was 1.35 m2. Bioprosthetic valves were implanted in 77 patients (85.6%). In-hospital mortality was 2.2% (2 of 90). There were 13 late deaths. New York Heart Association (NYHA) functional class improved to class I in most of survivors. Survival rates for 5 and 10 years were 84.9 and 71.2%, respectively. The outcome of aortic valve replacement with 19-mm prosthetic valve in elderly patients was excellent.

Aged↗
PubMed1983

[Aortic and tricuspid valve involvement caused by myxoid degeneration associated with a severe mitral prolapse. Apropos of 2 patients undergoing a double valve replacement].

Idiopathic mitral valve prolapse due to severe myxoid degeneration may be associated with aortic and/or tricuspid valve disease of the same aetiology. These localisations, which usually give rise few symptoms, can be detected by echocardiography. Sometimes, however, they may give rise to serious valvular regurgitation requiring surgical correction at each diseased valve. The authors report two cases of "floppy" mitral valve prolapse, the first requiring mitral and tricuspid, and the second, mitral and aortic, valve replacement. These cases underline the value of especially by echocardiography, in view of their serious complications.

Adult↗
PubMed1980

[Rheumatic cardiopathy in childhood. Epidemiological aspects, and differential diagnostic problems as compared with congenital bicuspid aortic valve and mitral valve prolapse].

A decrease in severity of rheumatic fever, in the number of recurrences of the disease, a relative decrease in prevalence of rheumatic heart disease compared to other forms of heart disease are well documented or suggested by the data collected in the last decades. The reasons of the decline are uncertain. Prevalence surveys in more recent years indicate that, while at one time almost all valvular heart disease was considered to be rheumatic in origin, current data suggest that a significant proportion of damaged valves may be attributed to congenital defects or to acquired disease of other etiologies. Bicuspid aortic valve and mitral valve prolapse deserve special mention. The main clinical and echocardiographic features of bicuspid aortic valve and mitral valve prolapse are discussed.

Adolescent↗
PubMed1994

[A case of perforated mitral valve aneurysm following aortic valve replacement associated with infective endocarditis].

A case of perforated mitral valve aneurysm following aortic valve replacement associated with infective endocarditis was reported. The patient was a 29-year-old man, who was suffering from high fever, Osler's nodules and headache. A brain abscess was recognized in a computed tomography and 3rd grade aortic regurgitation was recognized in echocardiogram and aortography. Hematological studies suggested the inflammation and gram-positive cocci was incubated from his arterial blood. Then infective endocarditis with aortic regurgitation was diagnosed. AVR was performed following 8 weeks treatment with antibiotics, when he had negative CRP and his blood culture. After the operation, he was received the intravenous antibiotic therapy for 6 weeks and oral antibiotic drugs was given following his hospital discharge. At 6 months after AVR, mitral valve aneurysm was recognized in his echocardiogram. At 30 months after AVR, the perforation of it was revealed and mitral valve replacement was performed with his negative blood culture. The patient was discharged 28th day after MVR. There has been no active inflammation from his first hospital discharge and following days, the mitral valve aneurysm and the perforation was caused by weakened tissue of the anterior mitral leaflet due to sibilant inflammatory change.

Adult↗
PubMed2000

Differences in left ventricular response between rheumatic and myxomatous mitral valve disease following mitral valve replacement.

OBJECTIVE: We studied whether differences exist between hearts having rheumatic mitral valves and those having myxomatous mitral valves, in functional, geometrical, and mass changes in the left ventricle after mitral valve replacement. METHODS: Patients who underwent mitral valve replacement without preservation of annular-papillary continuity for pure mitral incompetence were classified into rheumatic and myxomatous based on valvular histopathology. Echographic data measured before surgery was compared to that about 3 weeks after surgery. RESULTS: In the rheumatic group, ejection fraction decreased from 57.5 +/- 10.8 to 47.7 +/- 12.0, indexed left ventricular internal dimension in systole (mm/m2) from 24.7 +/- 6.8 to 20.7 +/- 6.2 (P = 0.0001), and left ventricular mass index (g/m2) from 205 +/- 55 to 138 +/- 54 (P = 0.0002). In the myxomatous group, ejection fraction decreased from 60.4 +/- 11.6 to 39.7 +/- 14.5 (P = 0.0001), indexed left ventricular internal dimension in systole from 24.2 +/- 5.6 to 23.1 +/- 5.5, and left ventricular mass index from 195 +/- 83 to 111 +/- 72 (P = 0.0004). Mean wall thickness index and relative wall thickness showed significant differences between the two groups postoperatively but no significant difference preoperatively. CONCLUSION: Hearts dilated due to chronic mitral incompetence respond differently after valvular replacement with total chordal excision depending on whether a rheumatic or myxomatous mitral valve is involved.

Chordae Tendineae↗
PubMed1993

Allograft replacement of the aortic valve versus the miniroot and valve.

Between February 1986 and April 1992, 27 patients ranging in age from 8 to 65 years (median, 18 years) underwent allograft replacement of the aortic valve with one death (operative mortality, 3.7%). The indications for operation were aortic regurgitation in 14 patients, aortic stenosis in 7, aortic stenosis/regurgitation in 4, and endocarditis in 2. Associated lesions included annuloectasia in 4 patients (1 with Marfan's syndrome), sinus of Valsalva aneurysm in 3, coronary artery disease in 4, and ventricular septal defect in 2. The freehand technique was used in 12 patients and the miniroot replacement in 15 patients. The postoperative transvalvular gradient was 17 mm Hg in freehand valves and 7 mm Hg in the miniroot valves. Initial postoperative study showed no or trivial aortic regurgitation in all 26 survivors except 1 freehand patient who had mild aortic regurgitation. At late study up to 6 years postoperatively all 10 of our available freehand patients showed progressive regurgitation, and it was severe in 4 patients. By contrast only half of the miniroot patients showed progressive regurgitation, and in none was it severe. Allograft replacement of the aortic valve can be done in children and adults with low mortality rate, short hospital stay, and excellent early function. Subsequent follow-up studies suggest that the miniroot replacements are superior to the freehand valves with lower transvalvular gradients, less valvular regurgitation, and delayed progression of valvular regurgitation.

Adolescent↗