Prosthetic valve endocarditis. A clinicopathological study of 31 cases

Prosthetic valve infective endocarditis was found in 31 out of 275 autopsies on patients with valvular prostheses. Mean postoperative survival was 332 days. Thirty patients had mechanical valves and only 1 had an infected tissue valve. The commonest pathogens were staphylococci, followed by Gram-negative bacilli and fungi. In all the patients with mechanical valves the infection was situated at the host-prosthesis sewing ring interface, and most also had vegetations on the prosthetic struts or cage. The infected tissue valve had vegetations on the prosthetic cusps only. Ring abscesses were present in one-third of cases and had destroyed the bundle of His in 1 patient. Clinically recognized pre-operative infective endocarditis was present in only 3 out of the 31 patients. Seven of the 31 patients died because of malfunction of the prosthesis, 10 died of systemic embolism, 4 of ruptured mycotic aneurysms, and the remaining 10 of other causes including myocardial failure, pyaemic abscesses and toxaemia.     

Intra-atrial implantation of mitral valve prosthesis in 2 patients with active infective endocarditis complicated by mitral annular destruction]

This is a report of two patients with extensive destruction of the mitral annulus due to active infective endocarditis. Patient 1 was a 66-year-old female and the patient 2 was a 59-year-old male. In both patients medical therapy had failed to control endocarditis and emergency mitral valve replacements were carried out. At the operation special surgical techniques were necessitated, since insertion of artificial valves in the annulus was impossible because of the lack of the annular tissue due to destruction and excision. On the posterior commissure side, mitral valve prosthesis were sutured to the left atrial wall just above the anatomical mitral ring. Furthermore, in patient 2, a bovine pericardium collar attached to the prosthetic valve was sutured to the left atrial wall to secure fixation of the prosthetic valve. The postoperative courses were uneventful in both patients. This technique seems to be useful in patients with mitral annular destruction.     

Bioprosthetic Versus Mechanical Valve Replacement in Patients with Infective Endocarditis

During the 5-year period, 1979-1984, at the Texas Heart Institute, 4,598 patients underwent cardiac valve replacement procedures of which 185 were for acute infective endocarditis. Staphylococcus and streptococcus accounted for 80% of the cases and congestive heart failure was a leading indication in 63%. The purpose of this article is to evaluate the recurrence of endocarditis dependent upon whether the patient had an Ionescu-Shiley bioprosthetic pericardial valve or a mechanical valve (St. Jude Medical). Actuarial freedom from both early and late reoperation was higher for prosthetic valves than bioprosthetic valve patients. We conclude that mechanical valves are the valves of choice in acute infective endocarditis which apparently is the results of less biologic tissue available for exposure to infection by the offending organisms.     

Infective endocarditis in a hancock bioprosthetic heart valve

Contemporary prosthetic heart valves (PHV) are a good mode of treatment of valvular heart disease. They last for an average of 5 to 10 years and bioprostheses fail due to the tissue degeneration. Infective endocarditis of the prosthetic valve is a relatively rare complication occurring in 0.5% to 1% of cases per year, and its late occurrence is even less common. Patients with PHV who undergo interventional or surgical procedures under adequate antibiotic coverage, infective endocarditis should not occur. We present a case of a 54-year-old woman who developed infective endocarditis on a porcine bioprosthesis, implanted 15 years earlier. The microorganism was Streptococcus viridans and the vegetations were surprisingly large and led to prosthesis obstruction.     

Emergency aortic valve replacement in active endocarditis with the Bj?rk-Shiley tilting disc valve prosthesis.

Because of severe and intractable heart failure in three patients with infective endocarditis, an emergency replacement of the aortic valve with a Bj?rk-Shiley prosthesis was carried out. Heart failure, which is the most common cause of death in infective endocarditis, was in these cases due to acute aortic regurgitation caused by perforation and other damage of the aortic valve. One patient died in the early postoperative period because of myocardial damage and respiratory insufficiency. The other two survived and are in relatively good condition after follow-up periods of 2 years and 6 months, respectively. The emergency replacement of incompetent valves may be a lifesaving procedure during the course of active endocarditis.     

Surgical aspect of active infective endocarditis

Twenty patients with active infective endocarditis, 11 with native valve endocarditis (NVE) and 9 with prosthetic valve endocarditis (PVE), were treated surgically from 1975 through April 1987 at Kyushu University Hospital. The operative indications were congestive heart failure mainly due to massive aortic regurgitation in 18, periannular abscess in 6, major embolism in 5 and severe hemolysis in 3 patients. In the group of NVE, single aortic valve replacement was performed in 4 patients and multiple valve replacement in the remainder. One patient died early postoperatively from LOS. Two patients with recurrent infective endocarditis, which occurred within 60 days after previous prosthetic valve replacement, were operated subsequently as early PVE. All other patients became NYHA class I postoperatively except for one patient who died from thrombosed valve. In the group PVE, re-AVR was done in 3, re-MVR in five, double valve replacement in two and re-fixation of the prosthesis to the aortic annulus in one patient. Two patients with early PVE died from recurrent endocarditis late postoperatively. One of 7 patients with late PVE, who had suffered from myocardial and cerebral infarction before reoperation, died from multiple organ failure. There were 3 patients with perivalvular leakage due to late active PVE, whose preoperative signs of inflammation were negative or minimum. As recurrent perivalvular leakage due to persistent infective endocarditis might frequently occur in such cases, complete resection and debridement of infected foci should be emphasized.     

Multivalvular surgery for infective endocarditis.

The short and the long-term results of our experience with 25 consecutive patients who underwent multivalvular surgery for infective endocarditis are analysed. Preoperatively, 20/25 (80%) patients were in New York Heart Association (NYHA) stage III or IV, and 2/25 (8%) patients were in cardiogenic shock. All the diseased valves were replaced with mechanical bileaflet prosthesis except seven mitral valves and one tricuspid valve, which could be repaired. Major postoperative complications occurred in 3/25 (12%) patients: a fatal cerebral haemorrhage, a reversible cerebellar syndrome and an intractable heart failure, which required transplantation. During a mean follow-up of 4.7 years (range 6 months to 16.8 years), 7/25 (28%) patients suffered from valve-related complications: five bleedings (one died), one embolic event and one prosthetic valve thrombosis. The actuarial freedom of valve-related event at 10 years was 61.8 +/- 12.4%. There was no prosthetic endocarditis. At follow-up, 20/21 (95%) survivors were in NYHA stage I or II. Long-term outcome in our patient population operated on for multivalvular endocarditis, is satisfactory with no recurrent infection and excellent functional results.     

The TTK chitra heart valve—A single centre experience with midterm results

Background The Chitra TTK heart valve has been in use at G.K.N.M. Hospital, Coimbatore, as the valve of choice. Initially this valve was used as part of a multi-centric trial and later it was the valve of choice in our institution. Methods Between December 1992 and July 1998, a total of 152 Chitra valves were implanted and these form the basis of this study. There were 65 aortic and 64 mitral implants and the rest were double valves. Results There was one early death due to infective endocarditis. There were 7 late deaths, 3 in aortic group (mean interval after surgery being 18.6 months), 3 in mitral group (interval of 8.6 months) and 1 in double valve group (interval of 7 months). The cause of the late deaths included endocarditis in 2 patients and choked valve in 2 patients. In the rest, the cause of death could not be ascertained. The remaining 144 patients were followed up (a total of 622 patient years of follow-up) with clinical and echocardiographic evaluation. There were 11 patients (7.2%) with thrombo-embolic episodes, 5 of whom had major events and the rest were minor with a linearized rate of 1.8 percent patient year. Haemodynamic studies in postoperative patients were comparable to other prosthetic valves. The thrombo-embolism free survival was 82% at 5 years. The actuarial survival was 78% at 5 years. Conclusion The Chitra valve is comparable to other mechanical valves     

Medium-term results of aortic valve replacement with cryopreserved homograft valves: importance of a domestic homograft valve bank

There are advantages to using aortic homografts as aortic valve replacements (AVR), particularly in patients with complex infective endocarditis. To determine the importance of a domestic homograft valve bank, our 23 surgical cases of homograft-AVR were reviewed. Since 2000, the Tissue Bank of the National Cardiovascular Center has supplied 23 aortic homograft valves for the treatment of complex aortic valve endocarditis. Fourteen of 23 patients had prosthetic valve endocarditis and 20 patients had an aortic annular abscess. The early mortality rate was 17% (4 patients), in all of whom prosthetic valve replacement had been performed previously. No recurrent endocarditis and no recurrent aortic regurgitation were noted at medium-term follow-up. An aortic homograft valve is the conduit of choice in cases of infective endocarditis and the importance of a domestic homograft valve bank should be recognized.     

Acute endocarditis treated with radical debridement and implantation of mechanical or stented bioprosthetic devices

BACKGROUND: Operation for active infective endocarditis carries high mortality and morbidity rates, especially when the annulus is involved. Overall the literature favors the use of autograft and homograft valves because of better resistance to infection. In our clinic during the last 5 years we used an aggressive surgical approach to infective endocarditis in combination with implantation of mechanical or stented bioprosthetic devices. METHODS: From 1994 to 1999, 50 adults with aortic and/or mitral valve endocarditis underwent valve replacement. The median age of the 36 men and 14 women was 58 years (range, 17 to 78 years). All patients had active endocarditis at the time of operation. Native valve endocarditis was present in 48 patients and prosthetic valve endocarditis was present in 2 patients. The aortic valve was affected in 24 patients, the mitral valve in 21 patients, and both the aortic and mitral valves in 5 patients. Two of the patients with mitral endocarditis also had infection of the tricuspid valve. Annular destruction was present in 24 patients (48%). The patients were treated with radical excision of all infected tissue. The annular defects were closed, if possible, with direct sutures. Otherwise, a reconstruction was performed. Follow-up was 100% complete with a median follow-up period of 45 months (range, 6 to 66 months). RESULTS: The procedures were performed without lethal bleeding complications. Early mortality was 12% and the actuarial survival at follow-up was 80%. In none of the patients who died was death related to the prosthetic valve or recurrence of the endocarditis. Only 1 patient (2%) developed recurrence of the infective endocarditis and was reoperated with a Ross procedure. Three and a half years later the patient developed severe valve insufficiency of the autograft and was operated again with implantation of a mechanical device. CONCLUSIONS: Native and prosthetic valve endocarditis can be treated successfully with aggressive surgical debridement and implantation of mechanical or stented bioprosthetic devices with a low risk of recurrent endocarditis.     

Bacteremia,Endocarditis, and the Hancock Valve

Among 373 patients with porcine xenografts, there were 27 instances of exposure of the xenograft to bloodstream or endocardial infection in 22 patients. Nine patients underwent 10 separate insertions of xenografts for active infective endocarditis. There were no early infections or valve failures. Three patients returned with a late prosthetic valve endocarditis (PVE) due to a new infection. There were 6 instances of bacteremia early after xenograft valve insertion with no early infection, no valve dysfunction, and 1 instance of late PVE. Eleven patients had PVE on a porcine xenograft. Blood cultures in the 10 patients treated with antibiotics promptly became negative. There were 3 valve-related deaths: 2 from valve incompetence and 1 from mitral and aortic xenograft stenosis. Our experience suggests that the Hancock porcine xenograft is: (1) as resistant to infection as are rigid prostheses in active infective endocarditis; (2) resistant to early postoperative bacteremias; and (3) easier to sterilize than rigid prostheses and more durable than other tissue valves in the face of PVE.     

Annular reconstruction for mitral valve replacement in a destroyed or calcified mitral annulus

Mitral valve replacement in the presence of severe annular calcification and an infectious lesion may be complicated by atrioventricular rupture, left circumflex coronary artery injury, and recurrence of infective endocarditis. Confronted with these circumstances, we have developed a technique of annular reconstruction for mitral valve replacement. The prosthetic valve is made by enlarging the circumference of the sewing ring with a Dacron collar. The collar can be sutured to the left atrial wall above the mitral annulus. This technique has been employed in five patients: three had extensive annular calcification, and two had acute valve endocarditis with destruction of mitral annulus. In all cases, the circumferential or partial annular reconstruction permitted secure implantation of the prosthetic valve. The one postoperative death was related to hemodialysis due to chronic renal failure. There were no other fatalities during the postoperative course, and the valves functioned normally. Our results suggest that this technique can be performed in high operative risk patients when mitral valve replacement is impossible using conventional techniques.     

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.     

Clinical evaluation of treatment for prosthetic valve endocarditis and analysis of factors affecting outcome of surgical therapy]

We analyzed the outcome for 18 patients with prosthetic valve endocarditis (PVE) treated between 1965 and 1990, 17 of whom had undergone valve replacement with mechanical prosthetic valves and one of whom had a bioprosthesis. Two patients developed infection within 60 days after surgery, and 16 thereafter. Fifteen patients received combined medical and surgical therapy and three medical therapy. In 14 patients, surgery had been performed during active infection. Mortality rate of those who had received combined medical and surgical therapy was 27%, and that of those who had received medical therapy was 67%. At operation, para-annular abscess was around the mitral prosthesis was found in three patients and around the aortic prosthesis in eight. Seven patients required reoperation for postoperative paravalvular leakage, in six, para-annular abscess had been found at the operation for PVE, and in one para-annular abscess had been noted. One patient who had undergone reoperation had developed reinfection after the first surgery and died due to multiple organ failure after the second operation (Danielson's translocation technique). In one patient who had complete loss of supporting tissue because of severe para-annular abscess, we had performed aortic valve replacement by implanting the aortic valve prosthesis into the left ventricle with Dacron felt-supported sutures placed in the mitral annulus and the muscles of the left ventricular outflow tract. This patient showed no postoperative infection or no paravalvular leakage.(ABSTRACT TRUNCATED AT 250 WORDS)     

Immediate and long-term results of valve replacement for native and prosthetic valve endocarditis

BACKGROUND: The objective of the present study was to compare current results of prosthetic valve replacement following acute infective native valve endocarditis (NVE) with that of prosthetic valve endocarditis (PVE). Prosthetic valve replacement is often necessary for acute infective endocarditis. Although valve repair and homografts have been associated with excellent outcome, homograft availability and the importance of valvular destruction often dictate prosthetic valve replacement in patients with acute bacterial endocarditis. METHODS: A retrospective analysis of the experience with prosthetic valve replacement following acute NVE and PVE between 1988 and 1998 was performed at the Montreal Heart Institute. RESULTS: Seventy-seven patients (57 men and 20 women, mean age 48 +/- 16 years) with acute infective endocarditis underwent valve replacement. Fifty patients had NVE and 27 had PVE. Four patients (8%) with NVE died within 30 days of operation and there were no hospital deaths in patients with PVE. Survival at 1, 5, and 7 years averaged 80% +/- 6%, 76% +/- 6%, and 76% +/- 6% for NVE and 70% +/- 9%, 59% +/- 10%, and 55% +/- 10% for PVE, respectively (p = 0.15). Reoperation-free survival at 1, 5, and 7 years averaged 80% +/- 6%, 76% +/- 6%, and 76% +/- 6% for NVE and 45% +/- 10%, 40% +/- 10%, and 36% +/- 9% for PVE (p = 0.003). Five-year survival for NVE averaged 75% +/- 9% following aortic valve replacement and 79% +/- 9% following mitral valve replacement. Five-year survival for PVE averaged 66% +/- 12% following aortic valve replacement and 43% +/- 19% following mitral valve replacement (p = 0.75). Nine patients underwent reoperation during follow-up: indications were prosthesis infection in 4 patients (3 mitral, 1 aortic), dehiscence of mitral prosthesis in 3, and dehiscence of aortic prosthesis in 2. CONCLUSIONS: Prosthetic valve replacement for NVE resulted in good long-term patient survival with a minimal risk of reoperation compared with patients who underwent valve replacement for PVE. In patients with PVE, those who needed reoperation had recurrent endocarditis or noninfectious periprosthetic dehiscence.     

Early surgery for active infective endocarditis.

OBJECTIVE: The timing of surgery for active infective endocarditis remains controversial. In this report, we have reviewed 26 patients who underwent surgery for active infective native-valve endocarditis between April 1992 and December 1998. PATIENTS AND METHOD: There were 19 male and 7 female patients (mean age 45 years). The aortic valve was involved in 8 patients, the mitral valve in 6 patients, tricuspid valve in 2 patients, both aortic and mitral valves in 7 patients, both aortic and tricuspid valve in 2 patients, and both mitral and tricuspid valve in one patient. The most common microorganisms were streptococcal species. Preoperative high New York Heart Association functional class (III and IV) was presented in 20 patients (77%). Progressive heart failure and the echocardiographic findings of vegetation (larger than 1 cm) were the main operative indications. Emergency or urgent surgery was required in 18 patients (70%). All patients underwent valve replacement, involving 25 mechanical prosthesis and 8 bioprosthesis. RESULTS: The operative mortality was 7.8% (n = 2). In the two patients who died, the infection had extended to the deep cardiac tissue and to the cerebral artery. The mean follow-up of the 24 survivors was 33 months (range from 6 to 82 months). There was no late death and no recurrence of infective endocarditis. CONCLUSION: In case of active infective endocarditis, early surgical intervention is recommended in patients with rapidly progressive cardiac deterioration or vegetation seen on echocardiography.     

The CarboMedics®"Top Hat" Supraannular Prosthesis in the Small Aortic Root

Twenty-three patients, 11 men and 12 women, with a mean age of 64 (range, 34 to 78) underwent aortic valve replacement (AVR) with a CarboMedics®“Top Hat” supraannular prosthesis between March 1993 and August 1994. The top hat supraannular prosthesis, a standard bileaflet valve with the cuff transferred to the valve inflow level, allowed implantation of 21-mm, 23-mm, and 25-mm valves, where a standard 19-mm or 21-mm valve would have usually been placed. One patient who had been in preoperative cardiogenic shock died in the perioperative period. Another had an intraoperative cerebral embolism with permanent impairment. Follow-up on 22 of 23 patients over a mean period of 9 months revealed mean Doppler gradients of 18 ± 6 mmHg, 15 ± 2.8 mmHg, and 11 mmHg, for the 21-mm, 23-mm, and 25-mm valves, respectively. Functional improvement was noted, with 17 patients in New York Heart Association (NYHA) Class I and 6 in NYHA Class II, postoperatively, compared with 0 in Class I, 9 in Class II, 10 in Class III, and 4 in Class IV, preoperatively. One patient showed reduced postoperative ventricular function with fractional shortening below 25%. Pandiastolic regurgitation intrinsic to the valve graded as slight was noted in all patients. Other postoperative complications included one patient with anticoagulant-related gastrointestinal bleeding and one other with prosthetic valve endocarditis successfully treated with antibiotics. The CarboMedics® top hat valve allows a gain in prosthesis size of 2 mm to 4 mm in the aortic position over standard prostheses, resulting in favorable postoperative hemodynamics.     

Heart valve operations in patients with active infective endocarditis

Sixty-two consecutive patients underwent heart valve operation for active infective endocarditis. There were 42 men and 20 women whose mean age was 49 years (range, 21 to 79 years). The infection was in the aortic valve in 37 patients, the mitral valve in 18, the aortic and mitral valves in 5, and the tricuspid valve in 2. Twenty-four patients had prosthetic valve endocarditis. Staphylococcus and Streptococcus were responsible for 86% of the infections. Annular abscess was encountered in 33 patients. Complex valve procedures involving reconstruction of the left ventricular inflow or outflow tract or both were performed in 31 patients. There were three operative deaths (4.8%). Predictors of operative mortality were prosthetic valve endocarditis, preoperative shock, and annular abscess. Patients were followed for 1 month to 130 months (mean follow-up, 43 months). Only 1 patient required reoperation for persistent infection. There were ten late deaths. Most survivors (96%) are currently in New York Heart Association class I or II. The 5-year actuarial survival was 79% +/- 7%. These data demonstrate excellent results in patients with native valve endocarditis, and support the premise that patients with prosthetic valve endocarditis should have early surgical intervention.     

Prosthetic valve endocarditis. The case for prompt surgical management

Clinical and morphologic features are described in 27 patients with prosthetic valve endocarditis. The interval from valve replacement to onset of symptoms of prosthetic valve endocarditis was less than 2 months in 10 patients, longer than 2 months but less than 6 months in seven patients, and longer than 6 months in 10 patients. The most frequent infecting organism was Staphylococcus (11 patients). In nearly all patients, infection spread behind the site of attachment of the valve prosthesis and resulted in valve ring abscesses. Twenty-three of the 28 infected prostheses were partially or almost completely detached, and in 15 patients the infection destroyed the entire valve anulus, burrowing to adjacent structures in six. Despite prolonged bactericidal antibiotic therapy, bacterial cultures of prosthetic valves removed at operation or autopsy were positive in 14 patients. Standard valve replacement was attempted in nine patients. All were hospital survivors, but two of these patients evidenced rapid postoperative valve dehiscence and required a complex surgical procedure at reoperation. The 14 other surgically treated patients had almost complete destruction of the annular root, and surgical repair was achieved by complex surgical techniques. There were five postoperative deaths, but nine patients survived with no further evidence of infection (mean follow-up 34 months). All patients with early prosthetic valve endocarditis who recovered underwent this type of operative technique. Total exclusion of the infected annular root, as described, may offer in patients with extensive endocarditic lesions the only possibility to eradicate the infection and to reduce the mortality.     

Candida parapsilosis tricuspid native valve endocarditis: 3-year follow-up after surgical treatment

In non-addicted patients, several states such as alcoholism, previous valvular heart disease or prosthetic valve replacement, immunodeficiency states, prolonged intravenous hyperalimentation, permanent pacemakers, and some congenital heart diseases can provide the predisposing factors for tricuspid valve endocarditis. It is an extremely rare occurrence in patients with normal native cardiac valves. In this report, we present a case of a 67-year-old woman with tricuspid native valve endocarditis related to Candida parapsilosis which is a very rare cause of infective endocarditis and carries a high mortality risk. An operation was indicated for the patient due to persistent enlarging vegetation on tricuspid valve, severe tricuspid regurgitation, septic pulmonary emboli and finally uncompensated respiratory and heart failure. She underwent tricuspid valve replacement with bioprothesis three years ago and now she is in a satisfactory condition without any medical treatment.