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PubMed1996

[Supraannular implantation of bioprosthetic valve for severe tricuspid valve regurgitation associated with atrial septal defect in an adult patient].

With an adult atrial septal defect, there was often regurgitation of the mitral and tricuspid valve due to volume overload in a long term period. Especially concerning tricuspid regurgitation, what can be done surgically has not yet been decided. For severe tricuspid regurgitation, some cases where tricuspid valve annuloplasty were performed have had exacerbation of tricuspid regurgitation. We experienced a case where tricuspid valve supraanular implantation without excision of native tricuspid valve (TVSI) was performed for severe tricuspid regurgitation associated with atrial septal defect, and improved. A 53-year-old female complained of dyspnea on exertion. An atrial septal defect was revealed being 4 cm in size, complicated with severe tricuspid regurgitation (IV), and 62 mmHg difference of pressure from the right atrium to right ventricle shown by a ultrasonography. Pulmonary artery pressure was 66/16 mmHg by cardiac catheter. Patch closure for ASD and TVSI for TR was performed on her, and amelioration of cardiac function was recognized.

Bioprosthesis↗
PubMed1996

Aortic valve replacement in patients 50 years old or younger with the St. Jude Medical valve: 14-year experience.

BACKGROUND AND AIMS OF THE STUDY: Ninety-one of 351 patients who received an aortic valve replacement (AVR) with the St. Jude Medical (SJM) valve at the Royal Melbourne Hospital between 1978 and 1990 were 50-year-old or younger. The results of these patients were retrospectively analyzed so that comparison may be made with the long term results of homograft AVR. MATERIAL AND METHODS: There were 75 males and 16 females. Mean age was 39 years (range 15-50 years). Valve pathologies were, congenital (32), degenerative (30), rheumatic (20), infective endocarditis (7). All patients had warfarin post-operatively. RESULTS: Follow up was complete with a total of 689 patients years, (range 34 months to 14.75 years, mean 7.6 years). There were two operative deaths (2.2%) and three late deaths (0.5 +/- 0.3%/patient-year) and two have undergone subsequent cardiac transplantation. Seventy-eight of 86 survivors (91%) are in NYHA functional Class I. At 10 years, actuarial survival was 94 +/- 2.9%, freedom from embolism was 96.4 +/- 2.4%, and from anticoagulant (AC) hemorrhage 89.4 +/- 6.5%. There were no structural failures; four cases paravalvular leaks were reported. Freedom from non-structural deterioration at 10 years was 95.3 +/- 2.3%. Freedom from reoperation was 95.6 +/- 3.2% at 10 years. Linearized rates (% per patient-year) were for embolism 0.6 +/- 0.5, AC hemorrhage 0.8 +/- 0.2, non-structural dysfunction 0.8 +/- 0.2 for endocarditis 0.4 +/- 0.5, and for reoperation 0.4 +/- 0.4. CONCLUSIONS: The SJM valve prosthesis has performed well in the aortic position in this younger group of patients up to 10 years.

Adolescent↗
PubMed1998

Impact of prosthesis-patient mismatch on hemodynamic and symptomatic status, morbidity and mortality after aortic valve replacement with a bioprosthetic heart valve.

BACKGROUND AND AIMS OF THE STUDY: Previous studies have shown that the effective orifice area of an aortic prosthetic valve may be too small in relation to the patient's body surface area, resulting in abnormally high gradients. The consequences of this condition, termed prosthesis-patient mismatch, have not been fully studied. The study objective was to determine if the condition has a detrimental effect on symptomatic and hemodynamic status, morbidity and mortality of patients undergoing aortic valve replacement. METHODS: A cohort of 392 patients was prospectively followed for up to seven years after implantation of a Medtronic Intact bioprosthesis. Doppler echocardiography was performed annually in 72 patients. Based on previous studies, presence of mismatch was defined as an indexed valve area < or = 0.85 cm2/m2. RESULTS: Mismatch was associated with less postoperative improvement of NYHA functional class (p < 0.009) independently of other predictors, such as age and preoperative functional class, but had no significant impact on patient survival (mismatch: 75 +/- 4%, no mismatch: 79 +/- 3%; p = 0.59) and valve-related morbidity up to seven years. Cardiac index was similar in patients with and without mismatch up to three years after operation but decreased significantly thereafter only in patients with mismatch (-0.54 +/- 0.32 versus -0.17 +/- 0.49 l/min/m2; p = 0.04). Likewise, the mean transprosthetic gradient, which was higher at one year after operation in patients with mismatch (22 +/- 8 versus 15 +/- 7 mmHg), increased significantly (+6 +/- 6 versus +1 +/- 1 mmHg; p = 0.008) only in this group during follow up. CONCLUSIONS: Patients with mismatch have less symptomatic improvement and worse hemodynamics that continue to deteriorate with time. However, medium-term prognosis (up to seven years) is relatively good. Further studies are necessary to determine the longer-term effects of mismatch on morbidity and mortality.

Aged↗
PubMed1978

Long-term survival after single aortic or mitral valve replacement with the present model of Smeloff-Cutter valves.

Two hundred fourteen survivors of single aortic (AVR) or mitral valve replacement (MVR) were evaluated. The present model of the Smeloff-Cutter prosthesis was used in these patients, and the series was started in September, 1966, following the last structural change in the valve. Clinical follow-up ended in September, 1976. Bleeding, thromboembolism, and peristent left ventricular dysfunction were the major complications. Thromboembolism occurred at a rate of 0.13 percent per month of patient follow-up. Late deaths occurred in 19.2 percent of patients, half of these within the first year. Acturarial data indicated a 5 year survival rate of approximately 75 percent after both mitral and aortic replacements. Bleeding and thromboembolism were more frequent causes of death after mitral replacement. Myocardial function was of greatest importance in long-term survival after replacement of either valve. Variations in warfarin dosage significantly affected both bleeding and thromboembolic complications.

Anticoagulants↗
PubMed1996

Nasal valve suspension. An effective treatment for nasal valve collapse.

OBJECTIVE: To evaluate a new operative technique for treating nasal valve collapse for safety and effectiveness. DESIGN: A nonrandomized pilot study of patients with complaints of nasal airway obstruction, a positive Cottle maneuver, and clinical findings of nasal valve collapse. Follow-up ranged from 1 to 20 months. SETTING: Academic medical center, including a Veterans Affairs hospital. PATIENTS: Twelve men aged 38 to 73 years (mean age, 59.3 years). MAIN OUTCOME MEASURES: Subjective self-assessment scores for nasal airflow were collected on a 10-point scale. Anterior rhinomanometry, acoustic rhinometry, and photographic analysis provided objective data. INTERVENTION: The procedure involves accessing the orbital rim by a transconjunctival incision, then passing sutures from the nose to this incision where they may be affixed to the orbital rim. The collapsing tissue of the nasal valve is thus supported and collapse is prevented. RESULTS: All patients reported immediate subjective improvement in their symptoms of nasal obstruction; this was reflected in their self-assessment scores. The rhinomanometry showed reduced nasal resistance in 10 (83%) of 12 patients. The acoustic rhinometry showed an increase in minimum cross-sectional area in 2 (33%) of 6 patients, with the others remaining stable. The photographic analysis revealed mild widening of the mid-third of the nose in 6 of 12 patients, although this was not of concern to the patients. There were no major complications. CONCLUSION: Nasal valve suspension is a safe and effective procedure for treatment of nasal valve collapse.

Adult↗
PubMed1996

The anesthesia machine valve tester: a new device and method for evaluating the competence of unidirectional anesthetic valves.

OBJECTIVE: Current methods of determining anesthesia machine unidirectional valve (UDV) competence are time-consuming, ineffective, or carry the risk of transmitting infectious disease to the anesthetist or patient. New methods of testing these valves are needed. The purpose of this study was to determine the prevalence of incompetent UDVs at one institution by employing the Anesthesia Machine Valve Tester (AMVT), a new way to test anesthesia machine UDVs. METHODS: We tested each expiratory and inspiratory UDV on all anesthesia machines in functioning operating rooms at the Brigham and Women's Hospital. If a UDV was found to be incompetent, we cleaned and reseated it, and then tested it again with the AMVT. RESULTS: We found a 13% prevalence of UDV malfunction in our machines. Three of the 10 incompetent valves were repaired quickly by us and were made competent by either reseating the valve or by first cleaning and then reseating it. CONCLUSIONS: We found that the AMVT was able to detect UDV failure quickly with no risk to the tester or to the patient. We conclude that the AMVT can be used to check the UDV as recommended by the FDA anesthesia machine check-out protocol.

Anesthesia, Closed-Circuit↗
PubMed2003

Lower anticoagulation for mechanical heart valves: experience with the ATS bileaflet valve.

BACKGROUND: The design of the bileaflet ATS (ATS Medical Inc., Minneapolis, USA) mechanical valve incorporates an open pivot at the hinge mechanism. Total washout of the blood at the pivot area was observed using 3-D computational fluid dynamics modelling. This phenomenon could make the valve less vulnerable to clot formation in patients without major thromboembolic risk factors. METHODS: From January 1993 to June 1999, 286 consecutive patients had the ATS valve inserted in the aortic position. Patients were divided into two groups. Group 1 comprised all patients in regular sinus rhythm with good left ventricular function (144 patients). Group 2 included patients in non-sinus rhythm and/or with large hypocontractile left ventricles (142 patients). The anticoagulation regime in group 1 was used to obtain an international normalised ratio (INR) between 1.5 and 2.5. This contrasts with our regular aim to maintain the INR strictly between 2.5 and 3.5 for all mechanical valves, as achieved in group 2. RESULTS: The follow-up period (99% completeness) ranged from 18 to 84 months. Survival (Kaplan-Meier) was 97 and 98% and 92 and 81% at 1 and 5 years in group 1 and group 2, respectively (P = 0.12). Log rank analysis failed to detect a statistical difference in thromboembolism or bleeding between both groups (P > 0.05). However, trends were in favour of group 1. Univariate analysis selected poor ventricular function and an 'erratic' INR value (P = 0.002) as risk factors for death. The sole independent risk factor for bleeding was the use of aspirin (P = 0.025). CONCLUSIONS: The excellent group 1 data and outcome encouraged us to continue our low intensive anticoagulation regime and perhaps should be regarded as a new concept for treatment of selected mechanical valve patients.

Journal Article↗
PubMed1999

A comparative study of the effects of a colorectal valve on the oro-anal transit time in patients with an augmented and valved rectum for urinary diversion.

OBJECTIVES: To evaluate the effect of the interposed colorectal valve on the flow of the proximal colonic contents to the rectum in patients with a valved urinary diversion to the rectum. PATIENTS AND METHODS: The oro-anal transit time (OATT) and segmental colonic transit time (SCTT) were estimated in two groups of 15 patients each (10 women and five men). In group 1, patients had a colorectal valve and in group 2 (control) they had no valve in the rectosigmoid area. The OATT and SCTT were evaluated using the 7-day method, whereby each patient swallowed 10 ring-shaped radio-opaque markers daily for 6 days, and a single abdominal radiograph was taken on day 7. The OATT and SCTT were then estimated as the number of retained markers divided by the daily dose of markers. RESULTS: The mean (sd) OATT was not significantly different (P=0.185), at 1.85 (1.21) days in group 1 and 2.49 (1.38) days in group 2. There were no sex differences in the values between the groups. The SCTT in the four areas of the colon again showed no significant differences within or between groups (P>0.05). CONCLUSION: Using a colorectal valve to functionally isolate the urinary rectal reservoir and thus reduce the high incidence of metabolic acidosis has no significant effect on intestinal transit times.

Adult↗
PubMed1990

Hand-made valved conduit with high-porosity knitted graft and glutaraldehyde-treated autologous pericardial trileaflet valve.

In 10 patients with various congenital heart defects requiring reconstruction of right ventricle to pulmonary artery continuity, a new hand-made valved conduit was introduced. To avoid late stenosis with peel formation of the graft, high-porosity Golaski knitted graft was chosen. The graft was sealed by fibrin glue, and autologous pericardium was treated with glutaraldehyde and used to construct a trileaflet valve inside the graft. This hand-made graft was pliable with good conformability. The valve function was found good in the intermediate follow-up in 8 patients. This composite valved conduit may be a good alternative to the xenograft valved conduit when allograft conduit is not available.

Bioprosthesis↗
PubMed2004

[Substitute valve at popliteal vein in treating deep venous valve insufficiency of lower extremities].

OBJECTIVE: To study the effectiveness of substitute valve at the popliteal vein in treatment of deep venous valve insufficiency of lower extremities. METHODS: From January 1996 to August 2002, 27 patients were diagnosed having deep venous valve insufficiency of lower extremities by color Doppler and radiography with an average disease course of 17.4 years. All 27 patients had varicose vein, 25 pain, 22 swelling, 25 pigmentation in ankle area and 19 chronic ulcerations. Two cases had been treated with great saphenous vein ligation and striping. Average vein pressure in resting position was (11.00 +/- 0.73) kPa, and the ambulatory venous pressure was (9.14 +/- 0.68) kPa. All patients were treated with substitute valve at the popliteal vein, and great saphenous vein ligation and stripping, some were treated with subfascial endoscopic perforating veins ablation. RESULTS: The average ambulatory venous pressure after operation was (5.94 +/- 0.82) kPa, were significantly different from that before operation(P < 0.01). The curative results were satisfactory, and all symptom and physical sign disappeared. After a mean follow-up period of 2-6 years, 21 cases had satisfactory results. CONCLUSION: Substitute valve at the popliteal vein have the value of widespread application.

Adult↗
PubMed1984

[Krupin's valve. Remarks on the surgery of glaucoma. Personal results apropos of 20 Krupin-Denver valves].

The literature concerning different kinds of draining implants used since the beginning of this century to increase the reliability of filtering operations to relieve glaucoma has been reviewed. The Krupin-Denver valve implant, which allows a filtration surgery with a pressure sensitive, unidirectional valve implant function drew the author's attention. This device consists in an open supramid tube sealed to a silastic tube ending with a slit valve which opens under a 11 to 14 mmHg intra ocular pressure. The supramid tube is inserted 1 to 4 mm long into the anterior chamber from the corneoscleral limbus, and the silastic tube is set under a scleral flap. Personal results are exposed from february 1981 to december 1983, 15 eyes have been treated (5 neovascular glaucomas, 5 glaucomas in aphakia, 4 congenital glaucomas and one chronic glaucoma). After mean follow up time of 13 months (1 to 34 months), the Krupin valve insertion controls the intraocular pressure in 14 eyes, without antiglaucoma medication in 5, and 7 cases are controlled with an additional local therapy, and further 2 cases with a general treatment. In the discussion, the improvements brought by this valve implant are studied facing the three great reasons of failure in the filtering operations as defined in 1980 by Molteno and Cairns: immediate post surgical hypotony, blockage of the internal end of the draining fistula, blockage of the external end of the draining fistula.

Adult↗
PubMed1996

Early primary valve ablation for posterior urethral valves.

Early diagnosis and the use of new pediatric endoscopic equipment have significantly improved the survival of infant boys with posterior urethral valves. The sequelae of urethral obstruction in these patients includes abnormalities in the urethra, bladder, ureters, and kidneys. The question remains of how best to treat all valve patients to maximize function of the entire urinary tract. Our experience with early valve ablation (EVA) suggests that the damaged bladder and upper tracts have a potential to heal if the obstruction is removed and the bladder is allowed to fill and empty cyclically in the first few months of life. One year after EVA, even patients with severe obstructive changes show return of normal bladder capacity and compliance, and resolution or improvement in reflux. Unfortunately, the renal insufficiency associated with valves often is secondary to primary renal dysplasia, with many patients progressing to renal failure and transplantation. Upper tract diversion has failed to improve long-term outcome in patients with renal dysplasia; furthermore, it jeopardizes the potential for bladder healing and normal bladder function. Therefore, even for patients with renal insufficiency, early primary ablation should be used as the definitive treatment for posterior urethral valves.

Follow-Up Studies↗
PubMed1997

Valve membrane adhesion as a cause of Ahmed glaucoma valve failure.

PURPOSE: The purpose of this study was to describe a possible mechanism of failure of the Ahmed glaucoma valve (AGV; New World Medical, Rancho Cucamonga, CA). METHOD: Two AGVS that failed to control intraocular pressure (IOP) were examined. In vivo examination consisted of unroofing the capsule surrounding the implant and injecting fluorescein-stained balanced salt solution into the tube. In one case the entire implant was removed and examined in vitro, and in the other case only the valve portion was removed. RESULT: No flow in either case extended beyond the valve. In both cases, the membrane valve system was found to be fused and could not be pulled apart. CONCLUSION: Failure of the AGV may occur due to adhesion of the valve membranes.

Anterior Chamber↗
PubMed2006

The 'Valve Racket': a new and different concept of atrioventricular valve repair.

OBJECTIVE: Mitral regurgitation due to prolapse of the mitral leaflets frequently compromises annuloplasty repair procedures. We present a new annuloplasty ring that overcomes this difficulty, preventing displacement of the leaflets into the atrium. METHODS: The 'Valve Racket' is a prosthetic ring transformed into a racket by means of handmade mesh using expanded polytetrafluoroethylene (ePTFE Gore-Tex). After transection of the marginal chordae tendineae, five sheep had the new racket implanted in the mitral (n = 3) and in the tricuspid position (n = 2). The surviving sheep underwent postoperative evaluation. RESULTS: After six months of operation, a standard transthoracic study showed competent valves without significant gradients and without residual valve regurgitation. The ring appeared encapsulated by a uniform fibrous tissue but the threads showed a completely denuded surface except in the zone proximal to the ring. Thrombi or calcification deposits in the ring, racket's mesh, or cardiac chamber were not observed. CONCLUSION: This initial experience confirmed the efficacy and simplicity of the technique.

Animals↗
PubMed2003

Isolation of intact aortic valve scaffolds for heart-valve bioprostheses: extracellular matrix structure, prevention from calcification, and cell repopulation features.

Extracellular matrix (ECM) scaffolds isolated from valvulated conduits can be useful in developing durable bioprostheses by tissue engineering provided that anatomical shape, architecture, and mechanical properties are preserved. As evidenced by SEM, intact scaffolds were derived from porcine aortic valves by the combined use of Triton X-100 and cholate (TRI-COL) or N-cetylpyridinium (CPC) and subsequent nucleic acid removal by nuclease. Both treatments were effective in removing most cells and all the cytomembranes, with preservation of (1) endothelium basal membranes, (2) ECM texture, including the D-periodical interaction of small proteoglycans with normally D-banded collagen fibrils, and (3) mechanical properties of the treated valves. Ultrastructural features agreed with DNA, hexosamine, and uronic acid biochemical estimations. Calcification potential, assessed by a 6-week rat subdermal model, was significantly reduced by TRI-COL/nuclease treatment. This was not true for CPC only, despite better proteoglycan preservation, suggesting that nucleic acids also are involved in calcification onset. Human fibroblasts, used to repopulate TRI-COL samples, formed mono- or multilayers on surfaces, and groups of cells also were scattered within the valve leaflet framework. A biocompatible scaffolds of this kind holds promise for production of durable valve bioprostheses that will be able to undergo probable turnover and/or remodeling by repopulating recipient cells.

Animals↗
PubMed2006

Left coronary ostial obstruction after aortic valve replacement with a supra-annular aortic valve.

We report a rare case of left coronary ostial obstruction after aortic valve replacement with a Top Hat supra-annular aortic valve, which was diagnosed with intraoperative transesophageal echocardiography and successfully treated with an unplanned coronary bypass. The patient was a 76-year-old woman (height 143 cm, weight 44 kg) with aortic stenosis and regurgitation. A 19-mm Top Hat valve was implanted in the supra-annular position because of a small aortic annulus. There was a possibility that the high profile of this prosthesis might block the left coronary ostium. There may be a problem with the use of this prosthesis in patients with small and rigid aortic roots with little compliance. Although the Top Hat valve has a great advantage for small aortic annuli, care in its use should be taken due to possible interference with the coronary ostia.

Aged↗
PubMed1984

Late (5 to 132 months) clinical and hemodynamic results after either tricuspid valve replacement or anuloplasty for Ebstein's anomaly of the tricuspid valve.

Late clinical and hemodynamic observations are described in 6 patients who had either tricuspid valve anuloplasty (TVA) (2 patients) or tricuspid valve replacement (TVR) (4 patients) 5 to 132 months earlier for Ebstein's anomaly of the tricuspid valve unassociated with right ventricular outflow obstruction. Of the 6 patients, 4 had improved postoperatively by 1 New York Heart Association functional class and 2 had improved by 2 functional classes. The cardiothoracic ratio decreased 5 to 12 months after either TVR or TVA in all 6 patients (from a mean of 0.72 to 0.62). Repeat cardiac catheterization 5 to 12 months after TVA or TVR disclosed that the right atrial mean pressure had increased from a median of 4.0 to 10.5 mm Hg (p = 0.05); the right ventricular peak systolic pressure had increased from 19.0 to 31.5 mm Hg (p = 0.02); the right ventricular end-diastolic pressure had increased from 5.0 to 9.0 mm Hg (p = 0.05); the systemic arterial peak systolic pressure had increased from 115 to 123 mm Hg (p = 0.03); and the cardiac index had increased (in all 4 patients in whom both pre- and postoperative values were available) from 1.7 to 2.9 liters/min/m2 (p = 0.06). Thus, the tricuspid valve operations in our 6 patients with Ebstein's anomaly were associated with a decrease in symptoms of cardiac dysfunction, a decrease in cardiac size, an increase in cardiac index and an increase in right ventricular and right atrial pressures. The elevation of the right atrial pressures postoperatively may have resulted from increased right ventricular filling pressures, persistent tricuspid regurgitation or bioprosthetic stenosis.

Adolescent↗
PubMed1990

Valvular heart disease, infected valves and prosthetic heart valves.

The major causes of systemic embolism from valvular heart disease (mitral, aortic and mitral valve prolapse), prosthetic valves (both mechanical and tissue valves) and infected valves (endocarditis) are reviewed from the standpoint of their incidence and complications. Recommendations for therapy with anticoagulants or other antithrombotic therapy are set forth following the guidelines recently provided by the Second American College of Chest Physicians Conference on Antithrombotic Therapy. Adherence to these recommendations can significantly decrease the risk of systemic embolism in patients with these valvular heart problems.

Embolism↗