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In canine experiments, venous patency and valvular competence were evaluated following transposition of a valve-containing vein segment, with an without a distal arteriovenous (AV) fistula. The effects of distal fistula size on valvular function were also examined. Autogenous valve-containing venous segment grafts were placed in the femoral position. With no adjuncts, 90% of the grafts showed either occlusion, severe extrinsic narrowing, or intraluminal filling defects on early venograms, although 75% of valves were eventually competent at death. Veins that had undergone thrombosis and recanalization were routinely incompetent. With a distal AV fistula, all veins remained patent and 86% demonstrated valve competence. With both an AV fistula and dextran 40, all veins remained patent and all valves were component. Separately, graded size of AV fistulas did not result in loss of valve competence. Following venous segment transposition, continuous venous patency appears necessary for eventual valvular function, and this is enhanced by both a distal AV fistula and dextran.
OBJECTIVE: To explore the symptoms, radiological findings and outcome after valve ablation in patients who present late with posterior urethral valves (PUV) and who typically have mild forms of the disease with often minimal upper tract changes; these patients frequently escape detection by ultrasonography in utero and the diagnosis may be delayed to as late as adolescence. PATIENTS AND METHODS: The charts of 70 boys (mean age 7.46 years, range 2-14) diagnosed late with PUV and treated with value ablation were retrospectively reviewed. Before ablation, history of voiding habits, voiding frequency, presence of enuresis, dysuria and the incidence of gross haematuria was recorded. Findings of a physical examination, laboratory testing (urine analysis and serum creatinine levels), ultrasonography and voiding cysto-urethrography (VCUG) were noted. After valve ablation, a review included a detailed voiding history and re-examination of abnormal variables including an assessment of enuresis, voiding frequency and ultrasonography. The mean (range) follow-up was 25 (1-78) months. One patient was lost after his first follow-up visit, but data were included to that time. RESULTS: The most common presenting symptom was voiding dysfunction; 47 (67%) presented with nocturnal enuresis, 42 (60%) with urinary frequency and 12 (17%) with a history of urinary tract infection. On physical examination 12 (17%) had mild age-corrected hypertension. Microhaematuria was present in 21 (30%) but all patients had normal serum creatinine levels. Ultrasonography showed hydronephrosis in 33 (47%) and a postvoid residual volume in 57 (81%). On VCUG, 52 (79%) patients had clear evidence of PUV, 22 (31%) bladder trabeculation, 11 (16%) vesico-ureteric reflux and eight (11%) diverticula. On cystoscopy, 67 (96%) patients presented with the classic sail-shaped PUV and three a ring-shaped valve. After surgical ablation of the valve most patients dramatically improved; 31 of 42 (74%) had resolution of urinary frequency, 24 of 33 (73%) of diurnal enuresis and 17 of 47 (38%) nocturnal enuresis. Of 57 patients, 39 (68%) established good bladder emptying. Of 33 affected, 20 (60%) had some reduction of hydronephrosis but 63% continued to have some symptoms of voiding dysfunction. CONCLUSION: PUV should be considered in boys presenting with voiding dysfunction. After valve ablation most patients improve dramatically. Despite surgery, enuresis, urinary frequency and poor bladder emptying persisted in some and required further treatment. The continued bladder dysfunction suggested that irreversible urinary tract damage may have occurred. Even in this apparently mildly affected group, long-term follow-up is essential.
The authors refer to findings concerning the valve systems of deep veins and the great saphenous, obtained by application of the Echo-Color-Doppler and endoscopic method. The authors noted that healthy valve structures tended to turn downwards as the loading pressure increased, subsequently returning to a normal morphological and functional state. Slow motion study also stressed the presence of apparently active valve movements, including participation by the vein wall. The term "parieto-valvular functional unit" could be used. The authors suggest the existence of a form of transitory functional valve prolapse responsible for the origin of valve insufficiency, also functional. The healthy valve could thus cede to high pressure, also avoiding any structural damage.
Replacement of the mitral valve through a standard vertical left atriotomy in patients requiring both aortic and mitral valve replacement can be very difficult. This is especially true in patients who have undergone previous median sternotomy. Replacement of the mitral valve through the aortic root after excision of the aortic valve is described in two case reports. This is a convenient approach when traditional exposure of the mitral valve is impractical in patients requiring double valve replacement.
Actuarial curves and linearized rates of occurrence are statistical functions that traditionally have been used to evaluate freedom from, or incidence of, valve-related events that occur as a result of aortic valve replacement (AVR); however, the instantaneous risk of an event can be more precisely pinpointed by the use of a time-related hazard function. This function was used to analyze 240 cases involving patients who underwent AVR with the Ionescu-Shiley bovine pericardial valve. Follow-up was for 10 years. The period from 60 to 70 months after implantation was apparently critical, since specific and cumulative events (intrinsic tissue failure, thromboembolism, prosthetic valve endocarditis, cumulated events, and death due to valve-related events) peaked during this period. We suspect important degenerative bioprosthetic changes take place during this period and are the cause, in part, for this pattern. In an effort to reduce the incidence of thromboembolism, close observation, and probably antiplatelet drug administration, should be initiated 60 months after implantation of this valve.
Some patients have increased resistance in the nasal valve area that is static and does not collapse. Anterior rhinomanometry is unable to document nasal valve disorders in these instances. A simple stent was devised to open the nasal valve area during anterior mask rhinomanometry. Three groups of subjects were studied with and without the stent. These groups were 1) patients with anatomic findings of nasal valve obstruction, 2) normal control subjects, and 3) normal control subjects with artificially created midseptal nasal obstructions. At peak inspiration the median decrease in resistance with the stent in place when compared to nonstented values was 0.91 Pa.cm-3.s-1 for group 1, 0.27 Pa.cm-3.s-1 for group 2, and 0.25 Pa.cm-3.s-1 for group 3. Comparisons using the nonparametric Wilcoxon test had a significance level of p less than .001. An easily fashioned, well-tolerated nasal valve stent can be readily incorporated in anterior mask rhinomanometry technique. With use of the stent, nasal valve obstruction can be accurately diagnosed and quantitated.
PURPOSE: We believe that primary valve ablation with observation is the preferred management for posterior urethral valves. However, debate continues as to the role of high diversion. We examined the long-term outcome of a large series of patients treated with primary valve ablation, and compared it to the outcome of high diversion and vesicostomy. MATERIALS AND METHODS: We reviewed the records of 100 patients treated with primary valve ablation (74%), vesicostomy (13%) or high diversion (9%) before 1985. Median followup was 11.2 years. RESULTS: Overall 13% of our patients had end stage renal disease by age 15 years. Three patients initially treated with valve ablation and 3 initially treated with vesicostomy later underwent high diversion but none benefited from the secondary procedure. Four patients initially treated with valve ablation subsequently underwent vesicostomy but only 1 benefited. Bladder storage capacity was well preserved. Diurnal urinary continence developed in 46% of patients at age 10 years and only 1 remained incontinent after age 20 years. One patient with diversion who awaits transplantation had a small contracted bladder. Recent urodynamic studies in 10 cases of delayed urinary continence have not shown decreased bladder compliance or capacity. Kaplan-Meier analysis of outcomes of the different treatments indicated no statistical difference in patient age at end stage renal disease development. However, comparing the number of surgical procedures in the different treatment groups revealed a significant increase in the amount of surgery in infants with diversion. Our results were equivalent to those of the best published series, many of which strongly advocate high diversion. CONCLUSIONS: By avoiding diversion in most cases bladder function is preserved and the need for bladder augmentation is decreased.
Surgical replacement of cardiac valves evolved significantly since its first use. Evolution of techniques and valves used was driven by the frequent complications encountered with surgically implanted valves. Transcatheter implantation of valves is a new technique which continues to be under investigation and promises to perform a task with less risk and potentially better outcome. In addition, new techniques are being developed to address minimizing mitral regurgitation. Progress in transcatheter valve implantation and catheter mitral annuloplasty is reviewed in this article.
Despite enormous progress concerning material and design, patients with artificial heart valves still face a considerable risk of serious complications (e. g. hemorrhage, thromboemboli, redos) which sum up to 5-20% within the first 10 postoperative years depending on type and position of the implanted prosthetic valve. Nowadays technical defects of mechanical valves are negligible and relevant complications are most frequently the consequence of inappropriate oral anticoagulation therapy. To avoid these complications a strict control of both the anticoagulation therapy and the functional integrity of the prosthetic valve is mandatory. Therefore with the aim of risk minimization the patient should be enabled to cooperate by means of methods which are easy to handle in his everyday environment. We present a reliable method for early detection of prosthetic valve dysfunction which can be applied daily with minimal effort by the patient himself.
BACKGROUND: The improvement of quality of life gains increasing importance for the judgement of operative techniques. Besides the commonly used mechanical substitutes or bioprostheses for aortic valve replacement, the interest in the Ross procedure is growing. The aim of the study was to compare the quality of life after the Ross procedure with that after mechanical aortic valve replacement with two different anticoagulation regimes (self-management or conventional therapy). METHODS AND RESULTS: Clinical, echocardiographic and quality of life investigations (SF-36) were performed in patients with mechanical aortic valve replacement and self-management of anticoagulation (group A, n = 20) or conventional anticoagulation therapy (group B, n = 20) and in patients after the Ross procedure (group C, n = 20). The mean ages were 59.5 +/- 9.2 (group A), 61.2 +/- 8.1 (group B) and 59.3 +/- 9 years (group C). Significantly lower values of quality of life (SF-36) were observed in group B compared with group A (5 of 9 subtests) and with group C (6 of 9 subtests) and also in the physical and mental health sum scales. CONCLUSION: In this study the quality of life in patients after the Ross procedure and similarly after mechanical valve replacement and self-management of anticoagulation is superior to the quality of life after mechanical valve replacement and conventional anticoagulation.
The purpose of this study was to determine what influence various combinations of mechanical and bioprosthetic valves in the aortic, mitral, and tricuspid positions had on late morbidity and mortality of 40 hospital survivors of triple-valve replacement. At operation the patients ranged in age from 27 to 69 years; 73% were women. The mean postoperative follow-up interval was 8.3 years, with a total follow-up of 331 years (100% complete). At 12 months after operation, functional class decreased from 3.3 to 1.6 (p < 0.05), cardiac index increased from 2.0 to 2.6 L.min-1 x m-2 (p < 0.05), and pulmonary artery pressures decreased from 59/27 to 40/17 mm Hg (p < 0.05). There were no differences in preoperative variables between groups. Actuarial survival for the 40 patients (exclusive of 30-day or in-hospital mortality, which was 31%) was 78% and 74% at 5 and 10 years. At the same milestones, freedom from reoperation was 96% and 54%, freedom from combined thromboembolism and anticoagulant-related hemorrhage was 68% and 56%, and freedom from all late valve-related morbidity and mortality was 64% and 25%. Comparison of the patients with two or more mechanical prostheses with the patients having two or more bioprostheses indicated no significant differences in actuarial freedom from late death, thromboembolic events, or anticoagulant-related hemorrhage. However the actuarial freedom from reoperation in the groups with two or more mechanical valves was lower than that of the groups with two or more bioprosthetic valves (0/10 versus 13/30; p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
OBJECTIVES: This prospective, blinded transesophageal echocardiographic study was performed to determine the relative contributions of leaflet redundancy and overlap versus intrinsic tissue thickening as mechanisms for the apparent increase in diastolic thickness of the mitral valve. BACKGROUND: Increased diastolic thickness of the mitral valve has been identified as an echocardiographic feature that predicts subsequent adverse sequelae in patients with mitral valve prolapse (MVP). METHODS: Eleven patients with clinical and transthoracic echocardiographic evidence of MVP and 11 age-matched control subjects underwent protocol transesophageal echocardiography to image the mitral valve in two orthogonal planes and to measure its thickness in systole and diastole. RESULTS: Maximal diastolic width of the slack, unloaded anterior leaflet was significantly greater in patients with MVP than in control subjects (mean +/- SD: 0.64 +/- 0.20 cm vs. 0.30 +/- 0.04 cm, p < 0.001). Similarly, diastolic posterior leaflet width was greater in patients with MVP (0.67 +/- 0.39 cm vs. 0.31 +/- 0.06 cm, p < 0.01). In contrast, minimal systolic width of the distended pressure-loaded mitral valve was not significantly different between patients with MVP and control subjects for either the anterior (0.22 +/- 0.05 cm vs. 0.20 +/- 0.04 cm, p = NS) or the posterior (0.25 +/- 0.07 cm vs. 0.24 +/- 0.05 cm, p = NS) leaflets. The percent change in leaflet width from diastole to systole (% delta W), an index of the contribution of dynamic factors (e.g., leaflet redundancy and overlap) to the apparent increase in diastolic leaflet thickness, was significantly greater in patients with MVP than in control subjects for both the anterior (% delta W 62 +/- 13% vs. 34 +/- 16%, p < 0.001) and the posterior (% delta W 54 +/- 19% vs. 22 +/- 21%, p < 0.005) leaflets. CONCLUSIONS: The apparent increase in diastolic mitral leaflet thickness in patients with MVP versus control subjects is largely attributable to dynamic factors such as leaflet redundancy, overlap and deformation. During diastole, when the mitral leaflets are slack and unstressed, the leaflets appear markedly thickened in patients with MVP. In contrast, during systole, when developed intraventricular pressure distends the leaflets, causing them to stretch and balloon into the left atrium, the intrinsic tissue thickness is much less than that measured in diastole. These findings have important implications for the morphologic criteria used to diagnose MVP and the potential pathophysiologic mechanisms for adverse sequelae in this syndrome.
Aortic valve-sparing procedures demonstrate excellent valvular function at midterm. Recently authors have reported acceptable early results with aortic valve-sparing procedures on patients with regurgitant bicuspid valves. We report the case of a novel procedure to preserve bicuspid valves with a calcified raphe and root dilatation. This procedure includes raphe excision, pericardial patch elongation, free edge leaflet reinforcement, and a root reimplantation valve-sparing procedure.
BACKGROUND: Several studies have compared left venticular mass (LVM) regression and hemodynamic data for stentless versus stented aortic bioprostheses with conflicting results. The major limitations of these studies are their small sample size and short-term follow-up. We therefore compared midterm LVM regression, hemodynamic data, and survival in a large population of tissue aortic valve replacement (AVR) patients. METHODS: All patients undergoing tissue AVR at our institution between 1998 and 2001 were included (n = 737). Patients were divided into two groups according to type of bioprosthetic implanted: stentless patients (total n = 310) (Toronto SPV [St Jude Medical, St Paul, MN], n = 146 and Freestyle [Medtronic, Minneapolis, MN], n = 164) and stented patients (total n = 427) (Perimount [Edwards Life Sciences Inc, Irvine, CA], n = 291 and Mosaic [Medtronic], n = 136). RESULTS: The two groups of patients had similar preoperative transvalvular gradients and LVM index (130 +/- 47 vs 130 +/- 42 g/m2 for stentless versus stented valves, respectively). Predischarge echos revealed that stentless patients had significantly lower mean transvalvular gradients (11 +/- 5 vs 15 +/- 6 mm Hg, p < 0.001) and larger effective orifice areas (1.32 +/- 0.52 vs 1.22 +/- 0.48 cm2, p = 0.01). Follow-up echocardiograms were obtained in 99% of surviving patients 28 +/- 22 (range, 0-79) months postoperatively. Stentless patients had significantly lower LVM index during follow-up (100 +/- 32 vs 107 +/- 32 g/m2, p = 0.005) and stentless valves were an independent predictor of LVM regression. Furthermore, a higher proportion of stented patients had residual LV hypertrophy during follow-up (28% vs 18%, p = 0.001). Stentless valves were associated with improved midterm survival by univariate analysis, but not by multivariable analysis. CONCLUSIONS: Midterm follow-up in a large number of patients reveals that stentless bioprostheses are hemodynamically superior to stented valves.
PURPOSE: In a recent study our group established an acute animal model of percutaneous pulmonary valve replacement using self-expanding nitinol stents. The present study was performed to evaluate these valved stents over a 3-month period. DESCRIPTION: Bovine jugular xenografts were sutured into nitinol stents. Transfemoral implantation in the pulmonary position using a modified commercially available application device (with a 22-French outer diameter) was evaluated in 9 sheep. EVALUATION: Two sheep died shortly after successful valved stent implantation due to internal venous hemorrhage. Another 1 sheep died 2.5 months after the procedure due to vegetations on the neovalve leading to subtotal stenosis. All other animals survived the 3-month study time (n = 6). An orthotopic pulmonary valved stent position was achieved in 4 animals and a supravalvular position in 1. During the deployment procedure, rhythm disturbances occurred in all animals, and mean arterial blood pressure dropped from 83.9 +/- 26.0 mm Hg to 68.3 +/- 22.3 mm Hg (p = 0.006) (n = 5). The peak-to-peak transvalvular gradient was 5.1 +/- 4.0 mm Hg initially (n = 5), and 3.6 +/- 1.6 mm Hg at follow-up (n = 5). Three-month angiographic and echocardiographic follow-up confirmed competent neovalves without paravalvular leakages. CONCLUSIONS: After 3 months of implantation, percutaneously implanted memory nitinol valved stents demonstrated good function in the sheep.
We describe a patient with Cornelia de Lange syndrome (CdLS) and a severely calcified bicuspid aortic valve. Cornelia de Lange syndrome is characterized by altered Notch signaling, and recent studies have provided a link between Notch signaling and heart valve development and calcific bicuspid aortic valve disease. In this case report, we propose that altered Notch signaling in CdLS may be causally linked to the calcific bicuspid aortic valve disease in these patients. Patients with CdLS should undergo routine echocardiographic examination for possible congenital cardiac defects including bicuspid aortic valve.