Time-related risk of the St. Jude Silzone heart valve.

OBJECTIVE: The St. Jude Medical Silzone heart valve had a silver-impregnated sewing ring designed to reduce the incidence of prosthetic valve endocarditis. Recruitment to the randomized AVERT study comparing Silzone valves with non-Silzone Control valves was stopped because of an increased risk of reoperation for paravalvular leak, but patient follow-up continues. Determining the time-related risk profile of the Silzone valve is important for helping physicians manage the approximately 28,000 patients currently alive with a Silzone valve. METHODS: Between 1998 and 2000, 403 Silzone and 404 Control patients were enrolled in AVERT. As of July 2005, there were 1819 Silzone and 1842 Control patient-years of follow-up (mean 4.5, median 5.1 years). Analysis emphasized the use and interpretation of hazard functions, since they are more meaningful than event-free percentages to currently surviving patients. To this end, instead of Cox regression, which estimates the hazard ratio, assuming it is constant over time, we employed primarily Aalen additive regression, which measures the hazard difference, and produces a plot of it over time. We assessed the risks of major paravalvular leak, endocarditis, bleeding and thrombo-embolism. RESULTS: The Silzone valve had a higher initial risk of major paravalvular leak than Control in the mitral (p=0.02) position, but not in the aortic (p=0.42) position. Analysis of this risk using additive regression, with all valve positions combined, showed that the initial risk due to Silzone lost statistical significance by 2 years and disappeared by 4 years after implant. In the mitral position, the Silzone valve had a higher initial risk of thrombo-embolism plus bleeding than Control; this risk also lost statistical significance by 2 years and subsided to zero by 4 years. The risks for death and endocarditis were similar for Slizone and Control valves. CONCLUSIONS: The additional risks of the Silzone valve, compared to Control, diminish over time and disappear by 4 years after implant. The minimum time after implant of the patients currently alive with Silzone is now well beyond 5 years; thus, these current patients now have a risk profile similar to that of patients with a standard St. Jude valve.     

Paravalvular leak and other events in silzone-coated mechanical heart valves: a report from AVERT

BACKGROUND: The Artificial Valve Endocarditis Reduction Trial (AVERT) was designed to compare endocarditis rates in Silzone versus conventional valves. Recruitment ended January 21, 2000, because of higher rates of paravalvular leakage in patients receiving the Silzone prosthesis. The present analysis determined late event rates that might be used in the management of approximately 36,000 patients who have received the Silzone prosthesis. METHODS: A total of 807 patients in 19 centers in North America and Europe were randomized. Mean age was 61+/-11 years; 41% were women. Operations included aortic valve replacement in 59%, mitral valve replacement in 32%, and aortic and mitral valve replacements in 9%; 41% had concomitant operations (26% coronary artery bypass grafting). RESULTS: Major paravalvular leakage (followed by repair, explant, or mortality) occurred in 18 of 403 patients receiving Silzone valves and 4 of 404 patients without Silzone valves (2-year event-free rates: 91.1% versus 98.9% conventional, p < 0.003). Similarly, 2-year freedom from any explant was lower in the Silzone arm (19 versus 2 events; 90.1% versus 99.4%, p = 0.0002). Rates of mortality and stroke were similar during follow-up. CONCLUSIONS: Continued follow-up of AVERT supports the conclusion that the Silzone prosthesis has increased risk of paravalvular leakage requiring reoperation. Overall survival is similar in the two groups.     

The St. Jude "Silzone" valve: midterm results in treatment of active endocarditis

BACKGROUND: The Silzone-coated St. Jude Medical valve (SJM "Silzone" valve), developed to reduce prosthetic valve endocarditis (PVE), was recalled by SJM due to a higher rate of paravalvular leaks. The aim of this study was to determine the efficacy of the SJM "Silzone" valve in avoiding PVE and to evaluate the frequency of paravalvular leaks, when the valve was used exclusively for active bacterial endocarditis. METHODS: From January 1998 to December 1999, the SJM "Silzone" valve was implanted in 40 consecutive patients with active endocarditis (20 aortic, 14 mitral, and 6 both valves). Late transesophageal echocardiography was performed in 87% of survivors, and transthoracic echocardiography in the remaining 13%. Follow-up was 100%. RESULTS: Hospital mortality was 17.5%. Early PVE occurred in 2 of 40 patients (5%). There were two late deaths without signs of recurrent PVE. A hemodynamic relevant paravalvular leak necessitating reoperation was seen in 2 patients within 6 months after operation. The rate of a minor paravalvular leak was 13% (4 of 31 patients). CONCLUSIONS: The SJM "Silzone" valve when implanted for active bacterial endocarditis does not give better results than other mechanical prostheses with regard to early recurrence of endocarditis. The rate of a hemodynamic relevant paravalvular leak requiring reoperation seems rather high during the early postoperative period, whereas the occurrence of minor paravalvular leaks is comparable with that of other mechanical prostheses. Routine observation, recommended for all patients with mechanical heart valves, is also sufficient for patients with the SJM "Silzone" valve.     

Pathologic analysis of 19 heart valves with silver-coated sewing rings

OBJECTIVE: The St. Jude Medical Silzone (Silzone) mechanical heart valve was voluntarily recalled (January 2000) due to an unusually high incidence of paravalvular leaks. We present the first series of human morphological data on the failure of these valves. METHODS: Nineteen Silzone valves were evaluated from the 176 Silzone valves implanted in 147 patients at our institution between 1997 and 1999. Explanted prostheses were fixed in 10% formalin, photographed, and X-rayed. Histological sections were collected from the sewing cuff, accompanying tissues, and thrombus. For comparison, six age-matched SJM-standard valves were similarly analyzed. RESULTS: Nineteen Silzone valves from 16 patients (10 male, six female, 52.0 +/- 15.2 years) were examined. Significantly more mitral (15/95) prostheses were removed than aortic (4/81) despite the nearly equal number implanted (p = 0.027). Fifteen of the Silzone valves (13/16 patients) were explanted in the early postoperative period (within six months of implantation), although collection continued for eight years after our institution stopped implanting them. The common indications for surgical explantation were paravalvular leak (8/12) and clinically suspected infective endocarditis (IE) (four patients, five valves). IE was not confirmed by histology or culture in any valve. The sewing cuffs of many Silzone valves showed large regions of pannus, granulation tissue, and purulent exudate. Polymorphonuclear leukocytes were more common in the sewing cuff of Silzone valves; however, the cellular infiltrate was superficial when compared to SJM-standard valves. CONCLUSION: This is the largest morphologically analyzed series of Silzone explants. It demonstrates a consistent pattern of atypical tissue incorporation into the silver-coated sewing ring particularly in the mitral position. Clinical and morphologic features of IE (sterile) are seen in the early postimplant period. Prosthesis-related problems were almost wholly seen at the mitral site, in our group. Our current data indicate that although early failure due to dehiscence and paravalvular leak is a problem, Silzone valves that "survive" past six months will likely function as well as the SJM-standard prosthesis.     

Repair of paravalvular leak after a third mitral valve replacement

This study reports on a 57-year-old woman who underwent a 3rd mitral valve replacement and presented with complaints of fatigue. Laboratory examination revealed severe hemolytic anemia, and trans-esophageal echocardiography revealed a paravalvular leak (PVL) around the prosthetic valve at the posterior trigone in the mitral position. PVL was regarded as the cause of hemolytic anemia. At surgery, a small tissue defect was detected around the calcified posterior trigone of the mitral annulus with no evidence of infective endocarditis. The mitral PVL was successfully repaired with suture closure of the annular defect. The postoperative course was uneventful: postoperative echocardiography revealed no evidence of PVL, and the hemolytic anemia subsided.     

Non infective severe aortic paravalvular leakage 7 years after surgery: the role of suture technique

We report a case of redo aortic prosthesis replacement for a severe paravalvular leak (PVL) in a man operated with continuous suture technique 7 years earlier. The severe aortic regurgitation was due to the rupture of the suture. In spite of operations to replace malfunctioning heart valves are common procedures and performed all over the world from more than 50 years, there is still an open debate about the most suitable suture technique. In this case report, we'll discuss if the suture technique has a role in preventing or leading complications as severe PVL.     

Repair of prosthetic mitral valve paravalvular leak using an off-pump transapical approach

Patients who present with significant paravalvular regurgitation after mitral valve replacement remain a difficult patient population and high-risk surgical candidates. We present 3 cases of transapical closure of mitral valve paravalvular leak (PVL) after mitral valve replacement using Amplatzer closure devices (AGA Medical Corp, Plymouth, MN). All 3 patients experienced decreased regurgitation at the site of the closure as well as symptomatic improvement in their heart failure.     

Percutaneous valve‐in‐valve procedure and simultaneous paravalvular leak closure

Concern for early degeneration limits the use of bioprosthetic heart valves. A 77‐year‐old man who underwent surgical aortic valve replacement at age 70 for severe aortic stenosis (AoS) presented with premature bioprosthesis degeneration and AoS recurrence. Transthoracic echocardiography demonstrated severe AoS and aortic regurgitation, a 30% ejection fraction, and pulmonary hypertension. Transesophageal echocardiography revealed that the aortic regurgitation was due to a 5‐mm paravalvular leak (PVL). A high EuroScoreII excluded surgical treatment. Simultaneous transcatheter aortic valve replacement and PVL closure with an Occlutech PLD Square 5 Twist PVL closure device were performed with good results and improved clinical status.     

Preservation of aortic leaflets during rapid deployment valve implantation in patients with aortic insufficiency

Development of a new surgical technique for aortic valve replacement with the use of rapid deployment/sutureless valve: a leaflet preservation technique applying imbrication methods to pliable aortic leaflets. We aim to decrease the incidence of paravalvular leak by preserving aortic leaflets in patients with aortic insufficiency and large aortic annulus.     

人工心脏瓣膜瓣周漏34例临床分析

目的探讨人工心脏瓣膜置换术后瓣周漏的治疗经验。方法分析1993年1月至2005年6月诊治的34例瓣周漏患者的临床资料,其中主动脉瓣位6例,二尖瓣位28例。9例行内科保守治疗,25例因明显贫血和（或）心功能衰竭（心衰）及内科治疗效果不好行外科手术治疗。手术直接修补瓣周漏漏口14例,另10例重新换瓣。结果保守治疗者中,2例在住院期死亡,死因分别为感染性休克、心衰;7例患者随访6～72个月,2例因心衰而死亡,余5例生活良好,超声心动图检查显示漏口无明显变化,心脏各房室无增大,心功能Ⅱ级。手术治疗者中,术中死亡1例,术后死亡3例（12％）;生存的21例患者术后随访4～132个月,1例二尖瓣和1例主动脉瓣瓣周漏修补术后瓣周漏复发,21例均生活质量良好,心功能Ⅱ级。结论对瓣周漏引起症状不严重,对血流动力学影响不明显,心功能良好的患者,可行内科保守治疗,定期随访。对有明显贫血和（或）心功能减退者,应尽早手术治疗。     

Eleven years' experience with Carpentier-Edwards biological valves in relation to survival and complications

The Carpentier-Edwards porcine valve bioprosthesis was implanted in 299 patients (325 prostheses) from April 1976 to April 1982. The series consisted of aortic valve replacement in 150 patients, mitral valve replacement in 120, multiple valve replacement in 26, pulmonary valve replacement in 2 and tricuspid valve replacement in 1 patient. The postoperative follow-up was 100% complete. The total accumulated follow-up was 1956 patient-years. The early mortality was 6.4% (20 patients) and the late mortality was 22% (62 patients). Valve-related mortality was seen in 8 patients (2.7%): 1 paravalvular leak during the 1st 30 postoperative days and 7 late mortalities (1 endocarditis, 2 paravalvular leaks and 4 deaths during reoperation). Three operative deaths (1.5%) occurred. The overall patient survival including operative deaths was 78.5% +/- 5% at 5 years and 66% +/- 4% at 10 years. The incidence of the different complications were: thromboembolism in 5 patients (1.7%) with a risk of 0.3%, haemorrhage in 1 (0.3%) with a risk of 0.05%, endocarditis in 2 (0.7%) with a risk of 0.1%, and paravalvular leak in 11 patients (3.7%) with a risk of 0.6%. There was a high incidence of tissue failure during the last 6 years which occurred in 54 patients (18%) with a risk of 2.7%. Sixty-seven patients (22.5%) were reoperated upon during the 11 years with an annual risk of 3.4% and the main cause of reoperation was primary tissue failure. The Carpentier-Edwards biological valve was shown to be efficient during the first 5 years of implantation after which the incidence of tissue failure increased.(ABSTRACT TRUNCATED AT 250 WORDS)     

Continuous-suture technique in aortic valve replacement

From April 2000 to April 2003 total 103 patients underwent aortic valve replacement and some concomitant cardiac procedures including mitral valve replacement in our hospital. According to the suture technique used in aortic valve replacement, the patients were divided into two groups: group A, 42 patients, the continuous suture technique with some modifications was used; group B, 61 patients, the conventional interrupted suture technique was used. There were no statistical differences between the two groups in age, sex, bodyweight, valve lesion, concomitant cardiac procedure and early mortality. But there were significant differences ([<0.001 approximately 0.012) in aortic cross-clamp time (AOCT) and cardiopulmonary bypass time (CPBT) between the two groups with less time for the group A patients. During a follow-up from 1 to 35 months, in group B, one patient developed perivalvular leak. The incidence of perivalvular leak was 1.7% (1/59). Three patients developed prosthetic bacterial endocarditis, the incidence of which was 5.0% (3/59). All the patients in group A recovered satisfactorily without suture technique or prosthesis associated complications. The modified technique was introduced and illustrated with diagrams, and the reasons for the advantages of the technique over the conventional interrupted suture technique were discussed.     

Intravalvular implantation technique for aortic valve replacement in aortitis syndrome

BACKGROUND: Paravalvular leakage is one of the most serious complications of aortic valve replacement in patients with aortitis syndrome. The purpose of this study was to compare the effectiveness of the intravalvular implantation technique in preventing paravalvular leakage with that of the conventional technique. METHODS: Since 1982, 14 patients with aortic regurgitation caused by aortitis syndrome have undergone aortic valve replacement at our institute. An intravalvular implantation technique was applied in 7 of the 14 patients. The technique consists of suturing a prosthetic valve to the aortic annulus and sandwiching the leaflets between exogenous felt pledgets and the inflamed aortic annulus. RESULTS: Paravalvular leakage occurred in 3 of 7 patients in the conventionally treated group and in none of 7 in the intravalvular implantation group. CONCLUSIONS: The intravalvular implantation technique is effective in preventing paravalvular leakage in patients with aortitis syndrome.     

Techniques for Management of the Calcified Mitral Annulus

Mitral annulus calcification is most often associated with myxomatous degeneration of the mitral valve. It is characterized by a horseshoe-shaped area of mitral annulus calcification that extends into the ventricular cavity to varying degrees. Standard suture techniques may be associated with fracture of the calcification and subsequent paravalvular leak. Seventeen patients aged 54 to 85 (mean 68.1) had mitral valve replacement using four techniques: suture through calcified annulus (3); decalcification (6); onlay patch (5); and drill technique (3). There were no hospital deaths, and one 81-year-old patient with associated coronary artery disease and ascending aortic calcification succumbed to a cerebrovascular accident three months postoperatively. The remaining patients are living and active with functional improvement. Follow-up has ranged from seven months to seven years with a mean of 4.0 years. One patient has hemodynamically insignificant mitral regurgitation after use of an onlay patch technique. No one technique could be singled out as clearly advantageous over the others from this series of patients.     

Technical modification of aortic valve replacement in aortitis syndrome —Report of a case—

In patients who have aortitis syndrome associated with aortic regurgitation, aortic valve replacement (AVR) is frequently complicated by perivalvular leakage (PVL). A 47-year-old male with aortitis syndrome and severe aortic regurgitation was treated by AVR, modified in such a way as to prevent PVL. The aortic cusps were not resected and were placed between Teflon pledgets and the aortic annulus. We believe that this technique is useful for preventing PVL in patients with aortitis syndrome in which the aortic annulus is severely inflammed.     

Technical modification of aortic valve replacement in aortitis syndrome--report of a case

In patients who have aortitis syndrome associated with aortic regurgitation, aortic valve replacement (AVR) is frequently complicated by perivalvular leakage (PVL). A 47-year-old male with aortitis syndrome and severe aortic regurgitation was treated by AVR, modified in such a way as to prevent PVL. The aortic cusps were not resected and were placed between Teflon pledgets and the aortic annulus. We believe that this technique is useful for preventing PVL in patients with aortitis syndrome in which the aortic annulus is severely inflammed.     

Mitral valve repair by Alfieri''s technique does not limit exercise tolerance more than Carpentier''s correction

Objective: The main goal of this study was to evaluate if the edge-to-edge mitral repair could be a limiting factor for exercise tolerance and to compare these results to those of classical techniques. Methods: Between 2000 and 2002, 54 consecutive patients were operated on for mitral valve regurgitation (MR). Twenty-five patients were operated with Alfieri's technique (group A) and 29 patients with Carpentier's technique (group C). The mean age was 63.9 years in group A and 63.8 years in group C (p = 0.98). After a mean follow-up of 16.2 ± 12 months, survivor patients were seen at the outpatient clinic, by the same physician for a clinical evaluation, an echocardiogram at rest and at peak exercise, and received a cardiorespiratory exercise testing with maximal oxygen uptake (VO₂ max) recording. Results: Clinical status improved with 0% of the patients in class NYHA III or IV in either group postoperatively versus 77% preoperatively. There was no significant MR in 80% of cases in group A versus 89.6% in group C (p = 0.54). The mean mitral valve area was 2.5 and 2.9 cm² in groups A and C, respectively (p = 0.018). The mitral gradient at rest was 3.8 and 3.3 mmHg (p = 0.31) and the mitral gradient at peak exercise was 8.5 and 9.7 mmHg (p = 0.22) in groups A and C, respectively. Cardiorespiratory exercise testing showed a mean VO₂ max of 73.7 ± 15% of normal value in group A versus 79.6 ± 13.1% in group C (p = 0.18). Conclusion: Alfieri's technique has the same efficiency on improvement of MR and clinical status than classical repair. Despite a higher restriction of mitral valve area at rest in group A, gradient and mean VO₂ max at peak exercise were similar in both groups.     

The “Annular Sandwich”: A Simple Method of Reinforcing a Friable Mitral Valve Annulus

In 6 patients undergoing prosthetic mitral valve replacement a ring of Teflon felt, instead of conventional Teflon pledgets, was used because of concern about seating a new prosthesis in a disrupted friable mitral valve annulus. The technique avoided the potential risk of pledget loss in the event of suture breakage and, in these patients, prevented postoperative paraprosthetic mitral valve regurgitation.     

Intermediate-term results with 1,019 carbomedics aortic valves

BACKGROUND: A retrospective study was conducted to evaluate the intermediate-term outcome in patients with the Carbomedics aortic valve prosthesis. METHODS: The study included 1,019 primary valve replacements between 1989 and 1997. Seventy-two percent of patients were men; mean (standard deviation) age was 61 (10) years. The preoperative New York Heart Association functional class was III or IV in 70% of patients. Follow-up at 9 years was 99.6% complete, comprising 2,730 patient-years (mean, 2.7 years). RESULTS: Patient survival, including operative deaths, was 80% at 7 years. The linearized death rate was 2.9%/year. Statistically significant risk factors for mortality were diabetes, pure valve insufficiency, advanced age at operation, and advanced preoperative functional class. Linearized rates were thrombosis, 0.1%/year; thromboembolism, 1.0%/year; hemorrhage, 1.7%/year; endocarditis, 0.1%/year; paravalvular leak, 0.1%/year; reoperation, 0.1%/year; and all events, 3.0%/year. The 7-year estimates of freedom from complications were thrombosis, 99%; thromboembolism, 93%; hemorrhage, 89%; endocarditis, 99%; paravalvular leak, 99.7%; reoperation, 99%; and all events, 82%. No structural valve failure was observed. CONCLUSIONS: The low incidence of valve-related complications favors the continued use of the Carbomedics valve in the aortic position.     

Predictors and treatment of persistent air leaks

Background. Air leaks prolong hospital stay.

Methods. A prospective algorithm was applied to patients. If patients were ready for discharge but still had an air leak, a Heimlich valve was placed and they were discharged. If the leak was still present after 2 weeks, the tube was clamped for a day and removed.

Results. There were 669 patients. Factors that predicted a persistent air leak were FEV_1% of less than 79% (p = 0.006), history of steroid use (p = 0.002), male gender (p = 0.05), and having a lobectomy (p = 0.01). Types of air leaks on day 1 that eventually required a Heimlich valve were expiratory leaks (p = 0.02), leaks that were an expiratory 4 or more (p < 0.0001), and the presence of a pneumothorax concomitant with an air leak (p < 0.0001). Thirty-three patients were placed on a Heimlich valve, and 6 patients had a pneumothorax or subcutaneous emphysema develop; all patients had an expiratory 5 leak or larger (p < 0.0001). Thirty-three patients went home on a valve. Seventeen patients had leaks that resolved by 1 week, 6 by 2 weeks, and the remaining 9 had their tubes removed without problems.

Conclusions. Steroid use, male gender, a large leak, a leak with a pneumothorax, and having a lobectomy are all risk factors for a persistent leak. Discharge on a Heimlich valve is safe and effective for patients with a persistent leak unless the leak is an expiratory 5 or more. Once home on a valve, most air leaks will seal in 2 weeks; if not, chest tubes can be safely removed regardless of the size of the leak or the presence of a pneumothorax.