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At least 775 records · Page 43Linked to original sources
PubMed1991

Mitral valve repair in the extensively calcified mitral valve annulus.

Mitral valve replacement in patients with an extensively calcified mitral annulus is associated with an increased risk of ventricular rupture. Until now techniques of mitral valve repair have not been applied to patients with a heavily calcified mitral valve annulus. We present 12 patients who underwent extensive decalcification of the annulus with subsequent mitral valve repair between 1987 and 1990. Ages ranged from 11 to 78 years; 6 patients were in New York Heart Association functional class II, 4 were in class III, and 2 were in class IV. All patients had varying degrees of mitral insufficiency. There were no deaths, reoperations, or thromboembolic events. Postoperative echocardiography revealed minimal residual mitral insufficiency in only 2 of 12 patients. All patients are currently in New York Heart Association class I or II. We believe mitral valve repair can be done safely on patients with an extensively calcified mitral annulus, thus avoiding the risks of left ventricular rupture, thromboembolic events, and hemorrhagic complications associated with mitral valve replacement.

Adolescent↗
PubMed1995

Ball valve (Smeloff-Cutter) aortic valve replacement without anticoagulation.

BACKGROUND: Because of the difficulty of permanent anticoagulation in our young population, Smeloff-Cutter ball valves have been used since 1986 at our institution for aortic valve replacement in selected patients without permanent anticoagulation therapy. METHODS: The availability of a satisfactory follow-up system since July 1988 suggested a study of all 47 patients operated on since then and followed for a mean of 43.2 months (range, 16 to 78 months). Mean age was 26.3 years, 98% were in sinus rhythm, and 16 patients (34%) had concomitant mitral repair. RESULTS: There were no hospital deaths. Three patients were lost to follow-up at a mean of 27 months. Four late deaths occurred (8.5%), two of them sudden, with actuarial survival at 6 years of 91% +/- 4.3%. There were a total of five embolic events (2.9%/patient-year). For isolated aortic valve replacement only, with antiaggregant therapy (n = 29), the incidence was 0.9%/patient-year. For all patients receiving antiaggregant agents (n = 43), it was 3.02%/patient-year. There were no known cases of valve thrombosis. Reoperation was required in 5 patients. CONCLUSION: Aortic valve replacement with the Smeloff-Cutter ball valve might be a valid alternative for young patients unable to maintain regular anticoagulation.

Actuarial Analysis↗
PubMed1985

Experimental study of physiological pulsatile flow past valve prosthesis in a model of human aorta--II. Tilting disc valves and the effect of orientation.

In Part II of this two paper sequence, pulsatile flow development past a tilting disc valve in a model human aorta has been studied using quantitative laser Doppler techniques. The valve was mounted in three different orientations with respect to the aortic root in this study. Under pulsatile flow, the region of flow reversal induced near the wall of the minor flow orifice extends to more than one tissue annulus diameter downstream from the valve into the ascending aorta. In a plane perpendicular to the tilt axis, a bi-helical secondary flow is induced distal to the valve. This secondary flow is further compounded by the multiple curvatures in the aorta. Hence the valve orientation affects the velocity profiles as far downstream as the mid-arch region as well as in the brachio-cephalic arterial branch. In the mid-arch region, a flow reversal along the entire cross-section is observed in early diastole for all the three orientations of the disc valve.

Aorta↗
PubMed1997

Effects of dobutamine on aortic valve indexes in asymptomatic patients with bileaflet mechanical prostheses in the aortic valve position.

We investigated the effects of alternating transvalvular flow rate on Doppler-derived aortic valve resistance and valve area in asymptomatic patients with mechanical aortic valve replacement under dobutamine infusion. The Gorlin-derived aortic valve area and continuity equation-derived aortic valve area seem to be less flow dependent; valve resistance tends to be flow dependent.

Adrenergic beta-Agonists↗
PubMed2002

Serotonin mechanisms in heart valve disease I: serotonin-induced up-regulation of transforming growth factor-beta1 via G-protein signal transduction in aortic valve interstitial cells.

Clinical disorders associated with increased serotonin [5-hydroxytryptamine (5-HT)] levels, such as carcinoid syndrome, and the use of serotonin agonists, such as fenfluoramine have been associated with a valvulopathy characterized by hyperplastic valvular and endocardial lesions with increased extracellular matrix. Furthermore, 5-HT has been demonstrated to up-regulate transforming growth factor (TGF)-beta in mesangial cells via G-protein signal transduction. We investigated the hypothesis that increased exposure of heart valve interstitial cells to 5-HT may result in increased TGF-beta1 expression and activity because of serotonin receptor-mediated signal transduction with activation of Galphaq, and subsequently up-regulation of phospholipase C. Thus, in the present study we performed a clinical-pathological investigation of retrieved carcinoid and normal valve cusps using immunohistochemical techniques to detect the presence of TGF-beta1 and other proteins associated with TGF-beta expression, including TGF-beta receptors I and II, latent TGF-beta-associated peptide (LAP), and alpha-smooth muscle actin. Carcinoid valve cusps demonstrated the unusual finding of widespread smooth muscle actin involving the interstitial cells in the periphery of carcinoid nodules; these same cells were also positive for LAP. Normal valve cusps were only focally positive for smooth muscle actin and LAP. In sheep aortic valve interstitial cell cultures 5-HT induced TGF-beta1 mRNA production and increased TGF-beta1 activity. 5-HT also increased collagen biosynthesis at the dosages studied. Furthermore, TGF-beta1 added to SAVIC cultures increased the production of sulfated glycan and hyaluronic acid. In addition, overexpression of Galphaq using an adenoviral expression vector for a constitutively active Galphaq mutant (Q209L-Galphaq) resulted in increased phospholipase C activity as well as up-regulation of TGF-beta expression and activity. These results strongly support the view that G-protein-related signal transduction is involved in 5-HT up-regulation of TGF-beta1. In conclusion, 5-HT-associated valve disease may be, in part, because of TGF-beta1 mechanisms.

Actins↗
PubMed2000

Percutaneous replacement of pulmonary valve in a right-ventricle to pulmonary-artery prosthetic conduit with valve dysfunction.

BACKGROUND: Valved conduits from the right ventricle to the pulmonary artery are frequently used in paediatric cardiac surgery. However, stenosis and insufficiency of the conduit usually occur in the follow-up and lead to reoperations. Conduit stenting can delay surgical replacement, but it aggravates pulmonary insufficiency. We developed an innovative system for percutaneous stent implantation combined with valve replacement. METHODS: A 12-year-old boy with stenosis and insufficiency of a prosthetic conduit from the right ventricle to the pulmonary artery underwent percutaneous implantation of a bovine jugular valve in the conduit. FINDINGS: Angiography, haemodynamic assessment, and echocardiography after the procedure showed no insufficiency of the implanted valve, and partial relief of the conduit stenosis. There were no complications after 1 month of follow-up, and the patient is presently in good physical condition. INTERPRETATION: We have shown that percutaneous valve replacement in the pulmonary position is possible. With further technical improvements, this new technique might also be used for valve replacement in other cardiac and non-cardiac positions.

Angiography↗
PubMed2003

Late outcomes of mitral valve repair for floppy valves: Implications for asymptomatic patients.

OBJECTIVES: We sought to evaluate the long-term results of mitral valve repair in patients with mitral regurgitation caused by floppy mitral valves and compare the outcomes of asymptomatic patients with those of symptomatic patients. METHODS: A retrospective review of 488 consecutive patients who had mitral valve repair for floppy mitral valve disclosed 199 patients who were asymptomatic or had minimal symptoms and 289 patients who were symptomatic at the time of the operation. Asymptomatic patients were younger, had better ventricular function, had a lower incidence of coronary artery disease, and had higher rates of atrial fibrillation than symptomatic patients. RESULTS: Survival at 15 years was 61% for all patients. Survival was 76% for asymptomatic patients, which was identical to that for the general population matched for age and sex, whereas the survival of symptomatic patients was 53% and significantly lower than that of the general population. Cox regression analyses validated by means of bootstrap methodology identified the following predictors of late death: age by increments of 5 years (risk ratio = 1.2), New York Heart Association functional classes 3 and 4 (risk ratio = 3.0), left ventricular ejection fraction of less than 40% (risk ratio = 2.7), preoperative stroke or transient ischemic attack (risk ratio = 3.1), previous cardiac operation (risk ratio = 4.6), and severe chronic obstructive pulmonary disease (risk ratio = 3.1). Freedom from reoperation at 15 years was 91%, and it was similar for asymptomatic and symptomatic patients. Freedom from mitral regurgitation of greater than 2+ at 15 years was 85% for all patients, 96% for asymptomatic patients, and 76% for symptomatic patients. CONCLUSIONS: This study supports the recommendation of surgical intervention in asymptomatic patients with mitral regurgitation caused by a floppy mitral valve if mitral valve repair is feasible and associated with low operative mortality and morbidity.

Aged↗
PubMed1990

Balloon dilatation of the aortic valve in a pulsatile flow model: assessment of the mechanisms and the magnitude and duration of changes in valve area and gradient.

Eighteen stenotic aortic valves (17 removed at operation) mounted in a pulsatile flow duplicator were dilated with a balloon catheter. Sequential measurements showed that the valve area initially increased from a mean (SD) of 0.52 (0.16) to 0.78 (0.17) cm2. It was 0.73 (0.16) cm2 five minutes after dilatation and this was little changed at four weeks (0.70 (0.15) cm2). Initially the mean transvalvar gradient fell significantly from 54 (27) to 32 (8) mm Hg but increased to 35 (10) mm Hg at five minutes and to 40 (11) mm Hg at four weeks. In six valves stretching of the orifice was the only mechanism responsible for the changes while in the remainder there was tearing through commissures with a greater initial increase in area (0.31 v 0.18 cm2) and a smaller decrease in area at five minutes (0.03 v 0.08 cm2). Fractures of calcific deposits in non-commissural positions were seen in one valve only. This laboratory study of isolated aortic valves showed a significant but small increase in valve area after balloon dilatation, which was greater when commissural tearing had occurred. Recoil of the stretched orifice was complete at five minutes and there was little further change over the next four weeks.

Adult↗
PubMed1991

Reduced exercise capacity in patients with tricuspid regurgitation after successful mitral valve replacement for rheumatic mitral valve disease.

OBJECTIVE: To determine how severe tricuspid regurgitation influences exercise capacity and functional state in patients who have undergone successful mitral valve replacement for rheumatic mitral valve disease. DESIGN: 9 patients in whom clinically significant tricuspid regurgitation developed late after mitral valve replacement were compared with 9 patients with no clinical evidence of tricuspid regurgitation. The two groups were matched for preoperative clinical and haemodynamic variables. Patients were assessed by conventional echocardiography, Doppler echocardiography, and a maximal treadmill exercise test in which expired gas was monitored by mass spectrometry. SETTING: University Hospital of Wales, Cardiff. SUBJECTS: 18 patients who had been reviewed regularly since mitral valve replacement. MAIN OUTCOME MEASURE: Objective indices of exercise performance including exercise duration, maximal oxygen consumption, anaerobic threshold, and ventilatory response to exercise. RESULTS: Mitral valve prosthetic function was normal in all patients and estimated pulmonary artery systolic pressure and left ventricular function were similar in the two groups. Right ventricular diameter (median (range) 5.0 (4.3-5.6) v 3.7 (3.0-5.4) cm, p less than 0.01) and the incidence of paradoxical septal motion (9/9 v 3/9, p less than 0.01) were greater in the group with severe tricuspid regurgitation. Exercise performance--assessed by exercise duration (6.3 (5.0-10.7) v 12.7 (7.2-16.0) min, p less than 0.01), maximum oxygen consumption (11.2 (7.3-17.8) v 17.7 (11.8-21.4) ml min-1 kg-1, p less than 0.01), and anaerobic threshold (8.3 (4.6-11.4) v 0.7 (7.3-15.5) ml min-1 kg-1, p less than 0.05)--was significantly reduced in the group with severe tricuspid regurgitation. The ventilatory response to exercise was greater in patients with tricuspid regurgitation (minute ventilation at the same minute carbon dioxide production (41.0 (29.9-59.5) v 33.6 (26.8-39.3) l/min, p less than 0.01). CONCLUSIONS: Clinically significant tricuspid regurgitation may develop late after successful mitral valve replacement and in the absence of residual pulmonary hypertension, prosthetic dysfunction, or significant left ventricular impairment. Patients in whom severe tricuspid regurgitation developed had a considerable reduction in exercise capacity caused by an impaired cardiac output response to exercise and therefore experienced a poor functional outcome. The extent to which this was attributable to the tricuspid regurgitation itself or alternatively to the consequences of right ventricular dysfunction was not clear and requires further investigation.

Aged↗
PubMed1983

Valve replacement for Ebstein's anomaly of the tricuspid valve. Early and long-term results of eight cases.

The role of valve replacement in the treatment of Ebstein's anomaly of the tricuspid valve remains controversial. Since 1965, eight patients with Ebstein's anomaly ranging in age from seven to 22 years of age (mean 13 years) have undergone tricuspid valve replacement (TVR) in our institution. Seven were in functional class 3 or 4 (NYHA), while one was in class 2, but had an increase in cardiac size. All of these eight patients showed moderate to severe cardiomegaly (cardiothoracic ratio: 54-75 percent). The valve was placed on the tricuspid annulus in seven of the eight cases, the exception being one case in which it was placed above the coronary sinus. Seven artificial prostheses (two Starr-Edwards, one Harken, one Kay-Shilley and three Wada-Cutter) and one porcine valve (Hancock) were used. There was one operative death in an early case due to postoperative complete heart block. Follow-up (range three to 18 years) of the other seven survival patients showed three late deaths; the first a pulmonary embolus 2.6 years after TVR; the second with congestive heart failure two years following the operation; and the third with arrhythmias five years after TVR. The remaining four patients are now in functional class 1 (three cases) and class 2 (one case). Valve replacement for Ebstein's anomaly can produce good clinical improvement and provide excellent long-term results.

Adolescent↗
PubMed1988

Preliminary results with an apico-aortic valved conduit (AAVC) using polyurethane and aortic allograft valves.

Stenosis of the left ventricular outflow tract is one of the most frequent congenital cardiac anomalies in dogs. The subvalvular stenosis is described as a ring of fibrous tissue located in the left ventricular outflow tract immediately below the aortic valve. The best method of surgical treatment in dogs seems to be relief of the aortic obstruction with a ventricular aortic prosthesis. A new trileaflet valve manufactured out of polyurethane has been developed. For the conduit a woven Dacron graft has been used. In 5 male dogs a valved conduit was implanted between the apex of the left ventricle and the aorta thoracica without using hypothermia and/or cardiopulmonary bypass. Four dogs survived the surgical procedure and showed no clinical symptoms postoperatively. Blood flow through the conduit was demonstrated postoperatively by angiocardiography for a maximum of 22 days, the longest surviving time being 8 weeks. Trials for the replacement of the artificial valve in the conduit by a canine aortic allograft valve are in progress. Studies were done with the cryopreservation of fresh aortic valves. Sterilization, cryoconservation, and storage methods for the allograft are described.

Animals↗
PubMed1980

Aortic valve replacement. A randomized study comparing the Björk-Shiley and Lillehei-Kaster disc valves. Transvalvular regurgitation and occurrence of paravalvular fistulas.

Three hundred patients were selected at random in order to compare the Björk-Shiley (B-S) and the Lillehei-Kaster (L-K) valves in the aortic position. The transvalvular regurgitation was evaluated by peroperative flow recordings in 97 cases. The leakage was found to be 7.6% and 7.5% of forward flow in the B-S and L-K valves, respectively. The regurgitant flow pattern, however, was different in the two groups, as leakage on closure was significantly larger in the L-K valves, and the leakage after closure of the disc was significantly larger in the B-S valves. Follow-up cine-aortography was carried out two years postoperatively in 91 patients. The contrast leakage through the valves was found to be minimal (Grade I) in about 90% in both groups. In one patient with a L-K valve no leakage could be demonstrated. In the remaining patients the leakage was moderate (Grade II). Paravalvular fistulas were demonstrated in three patients from each group. In one patient the paravalvular regurgitation was marked (Grade III), in the others moderate (Grade II). Cine-aortography was also carried out in a further 9 patients, in whom a paravalvular leakage was suspected according to clinical follow-up examinations. In four of these patients a paravalvular regurgitation was demonstrated. The leakage was moderate in two patients and severe (Grade IV) in another two, who were successfully re-operated on.

Aortic Valve↗
PubMed1999

The quality of life after aortic valve replacement with homografts or prosthetic valves.

BACKGROUND AND AIM OF THE STUDY: The study aim was to evaluate the quality of life in patients after homograft or prosthetic aortic valve implantation. Evaluation was based on clinical and echocardiographic examinations, and on analysis of data from patient questionnaires. METHODS: Patients undergoing either homograft (HV, n = 220) or prosthetic (PV, n = 220) aortic valve replacement were investigated. The patients groups were similar in age, sex, follow up period, risk factors and type of heart defect, and did not demonstrate any dysfunction of the replacement valve. RESULTS: During both pre- and postoperative periods, no significant inter-group differences were identified with regard to the occurrence of retrosternal pain, dyspnea, palpitation, fear reaction and circulatory efficiency based on NYHA classification, and self-evaluation of physical activity assessed by patient questionnaires. The majority of patients in both groups noticed on increase in their quality of life and physical activity. The reduced sexual activity (50%) and fear reaction (30%) in both groups did not correlate with their improved sense of well-being. Up to 14.6% of PV patients did not accept the implanted valve, and 65 (29.5%) would have preferred an HV, despite the need for reoperation. Following surgery, 21% of HV patients resumed work, compared with only 7.7% of PV patients. The frequency of claims for disability pension after surgery did not correlate with the considerate clinical and subjective improvement. CONCLUSIONS: In patients receiving either homograft or prosthetic valves, the subjective evaluation of life quality is comparable with the clinical evaluation, though the homograft valve was better accepted than its prosthetic counterpart.

Adult↗
PubMed1999

An exceedingly low operative mortality given by stentless autologous, homologous, and heterologous aortic valves for aortic valve replacement.

Homologous, autologous, and heterologous stentless valves were implanted into 663 patients undergoing aortic valve replacement by standard conventional methods. An exceedingly low mortality rate was achieved for the whole series, with the last consecutive 311 patients experiencing zero mortality. This analysis encompasses the hospitals' total experiences with these three stentless valves and examines only the low and zero mortalities. The three stentless valves were the aortic allograft used as a root replacement in 374 patients (mean age 43 years, 8.8% for active endocarditis), the pulmonary autograft used as a root replacement (22 patients, mean age 34 years) and the Cryolife O'Brien Model 300 stentless composite porcine glutaraldehyde-preserved aortic xenograft (267 patients, mean age 73 years, 16% 80 years or older, 55% concomitant procedures). Overall mortality rate was 1.1%. The seven deaths were essentially non-valve- and non-procedure-related. Of the last consecutive 311 patients, the mortality rate has been zero (166 allografts, 22 autografts, and 123 stentless xenografts). As a result of a careful, planned introduction of each valve and good experience and training in implant techniques, this low mortality and consecutive zero mortality suggest a "modern-day gold standard."

Adolescent↗
PubMed2000

[Valve replacement in severe aortic regurgitation following valve sparing operation with David's technique].

The aortic valve sparing operation is of great interest in the treatment of severe aortic insufficiency caused by annulus enlargement in aortic annuloectasia. If valve leaflets are normal, and we want to prevent complications derived from valve prosthesis and chronic anticoagulation, techniques like David s for valve preserving surgery will be performed. Although long-term results of these techniques are usually good, in some cases, like in the one we are dealing with here fibrosis is produced in the native valve, which evolves into a severe aortic insufficiency needing reoperation. We hereby describe the time related events of aortic valve deterioration, when the reintervention was indicated, and how the surgery was performed.

Adult↗
PubMed2001

Silzone-coated St. Jude medical valve: a safe valve.

Careful follow up studies in patients receiving a Silzone-coated St. Jude Medical valve (67 aortic valves, 36 mitral valves, nine double valves) did not support the fear of a high risk of perivalvular leak and embolism rate. Freedom from perivalvular risk at 12 and 24 months follow up was 98.5+/-1.5% and 100% for the aortic and mitral valves, respectively. Freedom from any thromboembolic event was 96.6+/-2.4% at 12 and 24 months follow up in the aortic group, and 97+/-3% at 12 and 24 months in the mitral group. The risk of bleeding (92.2+/-3.8% at 12 and 24 months in the aortic group; 85.5+/-6.0% in the mitral group) illustrated the risk of mechanical valve implantation in an elderly population.

Actuarial Analysis↗
PubMed1992

[A case of ascending aortic dissection after aortic valve replacement in congenital bicuspid aortic valve].

Congenital bicuspid aortic valve is a risk factor of aortic dissection, but the case is rare in Japan. Several reports described ascending aortic aneurysm after aortic valve replacement. In these reports, most of aneurysms were false aneurysm, but the cases of ascending aortic dissection were rare. In this case, dissecting aneurysm of the ascending aorta occurred 4 years after aortic valve replacement, which was performed with mechanical prosthesis because of infective endocarditis, and it was repaired successfully by the modified Cabrol's method. This case was congenital bicuspid aortic valve, and had already been complicated with moderate aortic dilatation in the ascending aorta. In patients of congenital bicuspid aortic valve with aortic dilatation, consideration of complete replacement of the ascending aorta with aortic valve replacement is important.

Adult↗
PubMed1992

Ventricular arrhythmias in aortic valve disease before and after aortic valve replacement.

In order to evaluate the effect of aortic valve replacement on the incidence of ventricular arrhythmias in patients with aortic valve disease, 24-hour ambulatory electrocardiographic recordings were obtained before surgery in 96 patients without coronary artery disease (aortic stenosis n = 50, combined aortic stenosis and regurgitation n = 19 and aortic regurgitation n = 27). Following aortic valve replacement, repeat recordings were obtained after 13 +/- 4 days and 18 +/- 7 months. Ventricular arrhythmias were in all cases classified according to Lown and were compared with clinical, echocardiographic and hemodynamic data. Preoperatively, ventricular premature beats were observed in 85 patients (89%) and were frequent (greater than 30 ventricular premature beats/hour) in 20 (21%). Multiformity was found in 27 (28%), couplets in 18 (19%) and ventricular tachycardia in 11 (11.5%). The occurrence of ventricular arrhythmias was not related to the type or severity of valve lesions. Patients with severe ventricular arrhythmias (Lown class 3 or 4: 37%) had a greater thickness of their interventricular septum 13.9 +/- 2.5 mm, vs 11.7 +/- 2.6 (p less than 0.05); a higher LV mass 176 +/- 34 g/m2, vs 134 +/- 39 (p less than 0.05) and a lower left ventricular ejection fraction 47 +/- 12%, vs 57 +/- 11, (p less than 0.01). Two weeks postoperatively, the incidence and severity of ventricular arrhythmias had increased: ventricular premature beats were noted in 92% and were severe in 50%. No correlation was found between ventricular arrhythmias and preoperative or operative data. Eighteen months after surgery, ventricular premature beats were still observed in 81% of patients but remained frequent in 7% only. Severe ventricular arrhythmias were noted in 27%. Patients with severe ventricular arrhythmias had at the time of this late recording a lower radionuclide left ventricular ejection fraction 57 +/- 14%, vs 73 +/- 9 (p less than 0.02) and a higher enddiastolic diameter 63 +/- 15 mm, vs 48 +/- 7, (p less than 0.01). This study indicates that ventricular arrhythmias are common in patients with aortic valve disease. The severity of arrhythmias is influenced by the LV consequences of valve lesion both pre- and late postoperatively. The frequency and severity of ventricular arrhythmias increase early after surgery and do not correlate with preoperative or operative data.

Adult↗