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At least 775 records · Page 43Linked to original sources
PubMed1999

Expanding the use of total mitral valve preservation in combination with implantation of the CarboMedics heart valve prosthesis.

BACKGROUND: Preservation of the mitral valve and subvalvular apparatus was introduced into the clinic in the early sixties, but for two decades the standard technique for mitral valve replacement included excision of both leaflets and their attached chordae tendineae. Lately, increased emphasis has again been placed on retention of the mitral subvalvular apparatus during valve replacement because of its role on left ventricular function. METHODS: We have preserved the valvular and subvalvular mitral apparatus, when possible, in connection with mitral valve replacement during the last seven years and the present investigation (partly prospective and partly retrospective) was done with the aim of making up the results of our mitral preservation technique. In the period between January 1990 and December 1995, 30% of the patients who underwent mitral valve replacement had complete retention of all mitral tissue. In 1996, the percentage had increased to 50, and during the first seven months of 1997, 70% of the patients had complete retention of all mitral tissue. Since January 1997, we have exclusively used the CarboMedics mitral heart valve prosthesis. A total of 56 patients were identified to have had a CarboMedics heart valve prosthesis implanted. There were 33 men and 23 women with a mean age of 63 years, range 23-77 years. Coronary bypass was a concomitant procedure in 22 patients. In seven patients, both the mitral and aortic valves were replaced. A severely altered valve with thickened and or calcified leaflets, stenotic leaflets, or shortened, retracted and thickened chordae tendineae were not a contraindication for the procedure. Calcified plaques were removed. Adhesion between anterior and posterior leaflets was treated with sharp dissection. Valve and subvalvular tissue were preserved. The leaflets were reefed within the valve-sutures and compressed between the sewing ring and the native annulus when implanting the valve prosthesis. Chordal tension on the ventricle was thereby maintained and the chordae pulled away from the valve effluent. Echocardiography with measurement of ejection-fraction was performed preoperatively during the postoperative course in case of cardiac problems and on a routine basis 1 month after surgery and at various intervals when the patient was seen in the outpatient clinic. Left ventricular outflow tract gradients were measured during the postoperative course in case of cardiac problems and routinely 1 month postsurgically. RESULTS: Five patients died in the postoperative period and one patient had transient neurological symptoms. In none of the patients was death or transient neurological symptoms a consequence of the retention of mitral leaflets with subvalvular apparatus. The remaining 51 patients were all alive at follow-up. Postoperative echocardiography demonstrated a preserved left ventricular function and a left ventricular outflow tract without obstruction. CONCLUSIONS: We find that the described technique in combination with implantation of a CarboMedics heart valve prosthesis is very useful even in patients with a severely altered valve, when preserving the mitral leaflets with subvalvular apparatus during valve replacement. The technique is without procedure related complications and preserves left ventricular function without obstructing the left ventricular outflow tract.

Adult↗
PubMed1999

Experimental studies on application of small-caliber vascular prosthesis produced by polyurethane.

It has been suggested that a microporous structure enhances fast and complete endothelialization. For long-term patency, antithrombogenicity and microporous structure are very important factors. In this paper, we have developed a new technique to give a micro-porous structure to small-caliber vascular prosthesis produced by polyurethane which has favorable antithrombogenecity. A mixed solution (tetrahydrofuran: dimethylformamide = 1:1) containing 13 wt% of segmented polyurethane and a variable amount of calcium carbonate (mean particle size of 8 mm in diameter) was dip-coated on a glass mandril of 3 mm and 6 mm in diameter and placed into distilled water for 24 hours. After the glass mandrill was removed, this polyurethane tube was placed into 1 mmol hydrochloric acid for 1 hour, and a microporous polyurethane vascular prosthesis of 20 mm in length was completed. These prostheses of 3 mm and 6 mm in diameter were implanted into the femoral and the carotid arteries, and the abdominal aorta of the dogs, respectively. Patency was recognized by arteriography and Duplex scanning and the removed grafts were inspected macro- and microscopically. Greater hydraulic permeability of this graft was obtained with an increase in the quantity of calcium carbonate mixed with polyurethane. In elasticity, this graft was more similar to the canine jugular vein than the polytetrafluoroethylene graft. Patency was observed 8 weeks after implantation on the arteriogram, and neointima was observed microscopically on the smooth and lustrous lumen. The new polyurethane vascular prosthesis we developed might provide a potential prosthesis for small-caliber vascular reconstruction.

Animals↗
PubMed2000

[Penile prosthesis for erectile dysfunction--long-term follow-up].

Our armamentarium for the treatment of erectile dysfunction has recently been expanded by addition of Viagra and the MUSE. However, their long-term results are still unknown. The insertion of a penile prosthesis is invasive, expensive, and irreversible, but under optimal condition provides an acceptable, definitive solution for erectile dysfunction. We evaluated our long-term results with penile prosthesis insertion (PPI). From 1987-1998, 57 patients underwent PPI in our department. Mean age was 55 years and the common causes of erectile dysfunction were atherosclerotic disease (23), radical pelvic surgery (15), and diabetes mellitus (14). Semirigid prostheses were inserted in 12 and inflatable prostheses in 45, including 42 single-component and 3 multi-component prostheses. Recently we interviewed these patients by telephone, using a standard questionnaire. Those not satisfied with the surgical results (83% of the living patients) were examined in our clinic. Mean follow-up was 53 months. In 37 (84%) the prosthesis was mechanically functional (rates after 1, 5 and 10 years were 87.8%, 80%, and 75%, respectively). In only 2 (2.5%) had serious complications led to prosthesis removal. All mechanical failures had occurred in those with inflatable prostheses after a mean of 48.5 months (range 4-113). At the time of the survey 68% were sexually active and 64% were satisfied with the surgical result. We conclude that PPI is safe treatment for erectile dysfunction. Although the rate of mechanically functioning prostheses decreases with time, modern multi-component prostheses may lead to better mechanical results.

Adult↗
PubMed1964

REPLACEMENT OF THE AORTIC AND MITRAL VALVES USING THE STARR-EDWARDS BALL-VALVE PROSTHESIS: A REPORT OF 50 CASES.

The aortic and mitral valves were replaced in 50 patients at the University of Alberta Hospital using the Starr-Edwards ball-valve prosthesis. The basis of the selection of 20 patients for isolated aortic valve replacement and 27 for mitral valve replacement using this type of prosthesis is presented, and the techniques of insertion of the aortic and mitral valve are described in detail. Of the 27 patients in whom the mitral valve was replaced by the Starr-Edwards prosthesis six died within 30 days of surgery and two after discharge from hospital at two and a half and four months, respectively. Left atrial thrombosis was the cause of death in four of these patients. In 20 patients in whom the aortic valve was replaced, four died in hospital and two died more than 30 days after returning home. Three of these six patients died from bleeding-the result of the use of anticoagulants. The difficulty in assessing whether or not anticoagulants are needed following replacement by a Starr-Edwards prosthesis is considered. It is felt, in our present state of knowledge, that anticoagulants should be used following mitral valve replacement but are probably not essential following replacement of the aortic valve. Two patients survived replacement of both aortic and mitral valves and have been followed up 18 months and seven months, respectively.

Anticoagulants↗
PubMed2004

Two-stage revision hip arthroplasty for infection: comparison between the interim use of antibiotic-loaded cement beads and a spacer prosthesis.

BACKGROUND: A two-stage revision is a well-accepted method for the treatment of a deep infection of a hip with a joint implant. In the present study, the results associated with the interim use of antibiotic-loaded cement beads were compared with those associated with the interim use of an antibiotic-loaded cement prosthesis. METHODS: One hundred and twenty-eight consecutive patients who were managed with a two-stage revision hip arthroplasty for the treatment of an infection were followed clinically and radiographically for an average of 4.9 years. Cement beads were implanted following resection arthroplasty in the first seventy hips, and a custom cement prosthesis was implanted in the subsequent fifty-eight hips. RESULTS: There was no evidence of recurrent infection in 122 patients (95.3%); the infection-free rates in both groups were similar. The use of a spacer prosthesis was associated with a higher hip score, a shorter hospital stay, and better walking capacity in the interim period; a decreased operative time, less blood loss, and a lower transfusion requirement at the time of reimplantation; and fewer postoperative dislocations. CONCLUSIONS: The present study supports the safety and efficacy of the routine use of an antibiotic-loaded cement prosthesis in the interim between the stages of a two-stage revision procedure for the treatment of an infection at the site of a hip arthroplasty.

Adult↗
PubMed1990

Dislocation of a posterior stabilized total knee prosthesis. A report of two cases.

Posterior stabilized knee prostheses have been recommended for knees with posterior cruciate deficiency, as well as for knees with prior patellectomy. Two cases are presented in which a complete dislocation of a Kinematic II Stabilizer prosthesis occurred after primary knee arthroplasty. The mechanism of dislocation was a varus or valgus stress while the knee was flexed. This previously unreported complication of dislocation after primary knee arthroplasty with a posterior stabilized knee prosthesis was, we believe, due, in part, to the design of this prosthesis, which provides little mediolateral stability in flexion, in combination with a mild degree of laxity of the collateral ligaments. This complication could be prevented by use of a prosthesis with greater inherent mediolateral stability.

Aged↗
PubMed1986

[Aseptic loosening of a total hip prosthesis].

Detachment of a total hip prosthesis, whether or not it is cemented, presents as an abnormal mobility between the implant and the bone. Mechanical pain, which may be continuous from the time of the operation or which may appear after a variable pain free period, is the usual presenting symptom. Clinical examination may induce the pain by forced rotation, by a shaking maneuver or by traction-impaction of the lower limb. The most suggestive signs of detachment of the prosthesis are the inability to extend the limb and the instability of weight-bearing on one foot. At this stage, the findings of radiological and laboratory investigations are able to characterise the type of detachment and its septic or aseptic nature. Two clinical situations can be defined on the basis of this survey: the diagnosis of detachment is obvious due to rupture or fracture of the prosthesis, of the cement or of the bone, by displacement of the prosthetic elements or by the destruction of the bone in contact with the prosthetic elements; the diagnosis may be suspected and can be confirmed by careful comparative analysis with the initial films or by further investigations: dynamic tests, scintigraphy, arthrography under traction and possibly coxonar. There are a number of causes of detachment: poor positioning, incorrect conception or design of the prosthesis, poor bony support and host reaction to the implant.(ABSTRACT TRUNCATED AT 250 WORDS)

Hip Fractures↗
PubMed1994

Revision total hip arthroplasty in the deficient femur with a proximal load-bearing prosthesis.

The proximal femur is frequently structurally deficient in revision hip arthroplasty, and makes obtaining prosthesis stability more difficult. Between 1984 and 1990, 174 patients were treated with revision total hip arthroplasty, performed by a standardized surgical technique, using cortical onlay strut allografts to restore the structural integrity of the femur, and a calcar replacement proximally porous-coated femoral prosthesis, composed of titanium alloy. The grafts united 98% of the time, and showed evidence of revascularization, and in some cases, complete incorporation. To date, six have been revised for femoral failure. Successful reconstruction of the deficient femur after failed total hip arthroplasty is dependent on several factors: the revision prosthesis must be stable, the deficient femoral bone stock must be augmented, and load must be transferred to the proximal femur so that the future proximal femoral resorption is minimized. The host femur and allograft will respond physiologically to load bearing, and the graft increases bone quantity and quality. The prosthesis must be supported primarily on host bone; the graft may enhance prosthetic support, but can never be used for primary prosthetic support when using uncemented revision prostheses.

Aged↗
PubMed1996

[Long-term results over 20 years of aortic valve replacement with the standard Björk-Shiley prosthesis].

Between January 1971 and December 1978, 865 standard Björk-Shiley prostheses (spheric or conic carbon disc) were implanted in the Department of Thoracic and Cardiovascular Surgery of the University Hospital of Rennes. Three hundred and fifty seven consecutive patients who underwent isolated aortic valve replacement were included in the study : 246 men (69%) and 111 women (31%) with an average age of 57.5 years (range : 24-80 years). One hundred and sixty eight patients (48%) were in NYHA Class II. 141 (39%) in Class III and 48 (13%) in Class IV. The valvular disease was stenotic in 304 cases (85%) and regurgitant in 53 cases (15%). The hospital mortality was 35 (9.8%). The main causes of death were cardiac (23 cases, 66%). The long-term results contain 322 survivors of surgery (mean follow-up 12 years, follow-up rate 99%, representing 3726 patient-years). The actuarial survival (including hospital mortality) was 76% at 5 years. 61% at 10 years, 47% at 15 years and 26% at 20 years. The average age of the survivors at present is 71 years and 95% are NYHA classes I or II. The causes of the 171 late fatalities were cardiac in 49 cases (1.3% per patient-year). Death was related to the prosthesis in 32 cases (0.8% per patient-year) : 3 endocarditis, 17 bleeding complications, 12 systemic emboli. Deaths were extracardiac in 58 cases (1.5% per patient-year). Prosthesis-related complications were : 9 paravalvular leaks (0.2% per patient-year), 3 dysfunctions (0.1% per patient-year). 24 haemorrhages (0.6% per patient-year), 5 thromboembolic episodes (0.1% per patient-year). 5 endocarditis (0.1% per patient-year). No structural abnormalities of the prostheses were observed. The authors confirm the reliability of the standard Björk-Shiley valve prosthesis in the aortic position and the value of the aortic valve replacement by a mechanical prosthesis even at very long term.

Actuarial Analysis↗
PubMed1975

Voice rehabilitation after laryngectomy. Results with the use of a hypopharyngeal prosthesis.

The Northwestern voice prosthesis for laryngectomees is described. The prosthesis contains no vibrator but activates vibration of the patient's pharyngeal or upper esophageal tissue by transporting air from the tracheostoma to a fistula in the upper neck, well away from major blood vessels. The prosthesis fits directly onto the laryngectomy tube and allows the patient to breathe, speak, and cough without any manual adjustments. The important advantage of this prosthesis is the fistula location. It can be placed at the time of original surgery and is also workable in patients who have had radiation and extensive radical surgery with total reconstruction of their gullet. The prosthesis can be used by primary total laryngectomees while learning esophageal speech or installed in those who are unable to use the electronic larynx or to learn esophageal speech. Four case studies are presented.

Adult↗
PubMed1997

Prevention of abdominal compartment syndrome by absorbable mesh prosthesis closure.

OBJECTIVE: To determine whether prevention of the abdominal compartment syndrome after celiotomy for trauma justifies the use of absorbable mesh prosthesis closure in severely injured patients. DESIGN: Retrospective analysis of case series from July 1, 1989, to July 31, 1996. SETTING: University-based level I trauma center. PATIENTS: Seventy-three consecutive trauma patients requiring celiotomy who received absorbable mesh prosthesis closure and 73 control patients matched for injury severity and trauma type who received celiotomy without a mesh prosthesis closure. INTERVENTIONS: Absorbable mesh prosthesis closure was used in cases of excessive fascial tension, abdominal compartment syndrome, necrotizing fasciitis, traumatic defect, or planned reoperation. MAIN OUTCOME MEASURES: Demographics, Injury Severity Score, Abdominal Trauma Index, highest abdominal Abbreviated Injury Scale score, number of abdominal/pelvic injuries, highest head Abbreviated Injury Scale score, shock, indication for mesh closure, complications, number of operations and time required for closure, days in the intensive care unit, length of stay, and mortality were determined. The highest abdominal Abbreviated Injury Scale score was multiplied by the number of abdominal/pelvic injuries to calculate the abdominal pelvic trauma score. RESULTS: Group 1 consisted of 47 patients who received mesh at initial celiotomy, and group 2, 26 patients who received mesh at a subsequent celiotomy. These 2 groups were statistically similar in demographics, injury severity, and mortality. However, group 2 had a significantly higher incidence of postoperative abdominal compartment syndrome (35% vs 0%), necrotizing fasciitis (39% vs 0%), intra-abdominal abscess/peritonitis (35% vs 4%), and enterocutaneous fistula (23% vs 11%) compared with group 1 (P < .001). Group 1 patients with preoperative abdominal compartment syndrome had more abdominal/ pelvic injuries and higher abdominal trauma index than matched controls (P < .05). There was a trend toward higher abdominal pelvic trauma score in patients who developed abdominal compartment syndrome. The Pearson coefficient of correlation between the abdominal trauma index and the more easily calculated abdominal pelvic trauma score was 0.91 (P < .001). CONCLUSION: The use of absorbable mesh prosthesis closure in severely injured patients undergoing celiotomy was effective in treating and preventing the abdominal compartment syndrome.

Abdomen↗
PubMedDate not supplied

Secondary tracheoesophageal puncture: factors predictive of voice quality and prosthesis use.

OBJECTIVE: To identify factors predicting prosthesis use and final speech quality in patients undergoing secondary tracheoesophageal puncture (TEP) for voice restoration alter laryngectomy. METHODS: We undertook a retrospective study of 168 patients who underwent secondary TEP at the Cleveland Clinic between June 1980 and October 1993. Factors examined were: patient demographics, extent of initial surgery, method of pharyngeal preparation, history of irradiation, insufflation test results, pharyngeal stricture, and concurrent medical conditions. Univariate and multivariate statistical analyses were performed to identify predictive factors. RESULTS: At last evaluation, 73.8% (124) of the patients were still using the prosthesis. Quality of speech was the only predictor of prosthesis use (p < .001). Phonation on the first day was achieved in 90% (151) of patients. Speech result improved significantly over the first 6 months (p < .001). Univariate analysis found that the need for reconstruction at laryngectomy (p = .04), the presence of pharyngeal stricture (p = .001), and continued prosthetic use (p < .001) were associated with the speech result. There was no significant advantage to the lack of approximation of the pharyngeal constrictors (p = .31). Stepwise logistic regression showed that only the absence of pharyngeal stricture was associated with a better-quality voice (p = .001). CONCLUSION: Tracheoesophageal puncture is a reliable method for restoring voice after laryngectomy. Prosthesis use decreases with time, and good voice quality is the only predictor of continued prosthesis use. In this series the absence of pharyngeal stricture was the only significant predictor of good to excellent speech.

Adult↗
PubMed1984

Randomized prospective trial of the Angelchik anti-reflux prosthesis.

Fifty-two patients with reflux oesophagitis resistant to medical treatment were randomized at operation to receive either the Angelchik prosthesis or a fundoplication. All patients were assessed postoperatively by a physician unaware of the nature of the operation. Forty-two patients have been followed up for 1-2 years; ten patients for 3-9 months. Ninety-six per cent of the Angelchik patients had satisfactory or excellent results compared with 81 per cent with a fundoplication. There were no failures to control reflux with the Angelchik prosthesis whereas 6 patients (23 per cent) of the fundoplication group have persisting reflux. Operating times for insertion of the prosthesis averaged a little over half that recorded for fundoplication. Complication rates were similar. The results of the trial encourage the use of the prosthesis in patients with gastro-oesophageal reflux, where medical treatment has failed. The prosthesis should not be used if the gut is opened during operation either inadvertently or deliberately, as in making a suture line or anastomosis, because of the risk of sepsis.

Clinical Trials as Topic↗
PubMed1985

Prospective study of the Angelchik anti-reflux prosthesis.

Fifty patients with medically refractory gastro-oesophageal reflux were treated by the insertion of an Angelchik anti-reflux prosthesis. All patients had a pre-operative upper gastrointestinal endoscopy, 32 were investigated with 15 h overnight oesophageal pH studies combined with oesophageal bile sampling and 20 underwent oesophageal manometric studies. At pre-operative endoscopy 45 patients had evidence of oesophagitis and the 5 who did not had pathological reflux demonstrated on overnight pH testing. Postoperatively the main clinical problem was dysphagia which appeared to settle with time but left one-third of patients with mild dysphagia at the end of 12 months. A further 12 per cent had residual moderate to severe dysphagia which required the removal of the prosthesis in five patients (10 per cent). In only one patient was the dysphagia due to prosthetic migration and this was the first patient in the series. Subsequently, we have had no problems with prosthetic migration, disruption, or erosion into the oesophagus. The overnight pH studies confirmed the efficacy of the prosthesis in preventing reflux which correlated with symptomatic improvement. We conclude that, while the Angelchik anti-reflux prosthesis is an effective device, it has a disturbingly high incidence of postoperative dysphagia though this appears to settle with time, leaving around 10 per cent of patients with severe dysphagia which will necessitate removal of the prosthesis and one-third with mild dysphagia which may settle with the further passage of time.

Adult↗
PubMed1982

[Silicone anti-reflux prosthesis--an artificial fundoplication?].

Of all anti-reflux operations fundoplication has proved the most effective method in experimental and clinical examinations [3, 5, 9, 12, 13]. In 1979 Angelchik reported a silicon prosthesis as an anti-reflux barrier which proved effective in examinations on patients. An explanation for these results is still missing [1]. Our examinations in dogs show that: 1. anti-reflux prosthesis is an effective anti-reflux barrier in dogs after circular myectomy; 2. silicon prosthesis proved to be equally as effective as fundoplication with regard to reflux prevention; 3. the mechanism of action is a mechanical one. The difference between silicon prosthesis and fundoplication is, that the fundoplication represents a 'ring' around the LES, which is elastic and is subject to the same regulations as the LES, and that it can relax in a swallowing reflex manner. In the silicon prosthesis the 'ring-formation' is only mechanical.

Animals↗
PubMed1994

Reconstruction of an iliac crest defect with a bioactive ceramic prosthesis.

Between June 1987 and December 1990, an iliac crest prosthesis made of bioactive apatite- and wollastonite-containing glass ceramic (A-W.GC) was used in 60 patients for the reconstruction of the iliac crest defect after harvesting autogenous tricortical iliac bone graft. The clinical results of this prosthesis were satisfactory. No patients felt spontaneous pain in the reconstructed area, and 93% of the patients had no tenderness there. In the radiological evaluation at the final follow-up, no apparent "radiolucent clear zone" was detected at the prosthesis-iliac bone junction in 98% of the patients. Excellent new bone formation between the prosthesis and the iliac crest was also noticed in 96% of the patients. The A-W.GC iliac crest prosthesis was beneficial for reconstruction of the iliac crest defect.

Adolescent↗
PubMed1984

Mentor inflatable penile prosthesis. Preliminary clinical results in 30 patients.

The Mentor inflatable penile prosthesis was designed to decrease the incidence of mechanical failures associated with the Scott inflatable penile prosthesis. The penile cylinders of the Mentor prosthesis are manufactured from Bioflex polyurethane, a new polymer which is more durable and less elastic than silicone. The Mentor prosthesis also has a connector system which employs plastic clamps rather than suture ties to fix tubings to connectors. The new prosthesis has been implanted in 30 patients with organic impotency. These patients have been followed for an average of 7.7 (5-12) months. All patients achieved a satisfactory cosmetic and functional result from the procedure.

Aged↗
PubMed1996

Effect of phosphatidylcholine on the process of peritoneal adhesion following implantation of a polypropylene mesh prosthesis.

The postimplantation peritoneal adhesions formed with some biomaterials continue to represent a serious problem when these biomaterials are placed in contact with the organs of the abdominal cavity. The objective was to test the effects of phosphatidylcholine (PC) in the attempt to modulate the adhesive process, thus improving the biomaterial/visceral peritoneum interface. We have carried out an experimental study using the New Zealand white rabbit, implanting a 7 x 5 cm2 polypropylene prosthesis into the anterior abdominal wall in such a way that it replaced all the tissue layers and was in contact with the intestinal loops. Three study groups were established: group I (control), in which only implantation of the biomaterial was performed; group II, in which the prosthesis was pretreated with a solution of PC; and group III, in which the implants were treated as in group II and the animals underwent intraperitoneal administration of 10 ml of the same solution. The animals were killed on postimplantation day 14. The total surface of the prosthesis occupied by adhesions was measured and light and scanning electron microscopy were performed to analyse the healing process. In comparison with the controls, groups II and III did not present significant differences with respect to the resistance or extension of the adhesions. The microscopic results showed a rapid formation of disorderly and well-vascularised scar tissue enveloping the entire prosthesis. Thus, PC was unable to modulate the process of adhesion formation between the prosthesis and the organs of the abdominal cavity; nor did it induce changes in the cells of sufficient importance to alter the results of the healing process in the presence of this biomaterial.

Animals↗