An analysis of autopsy findings in 108 patients who died after valve replacement

The pathological findings and the causes of death were reviewed in 108 patients who had received 142 heart valve prostheses (52 mechanical and 90 bioprostheses) at the National Cardiovascular Center in Osaka, Japan, from 1977 to 1991. Rheumatic heart disease was the major underlying disease (60.2%), and the age distribution at death ranged from 21 to 80-year-old. Survival duration after the surgery extended from 0 day to 9 years. Thirty-three patients (30.6%) died of perioperative complications such as myocardial haemorrhage and damage, or from heart failure which had been evident prior to the operation, a cause of death which predominated in patients who died within 1 week of surgery (15/17; 88.2%). Thirty-eight patients (35.2%) died of prostheses-related problems such as prosthetic valve failure (cuspal tears and calcifying destruction of the xenograft), thromboembolism, and prosthetic valve endocarditis. Endocarditis was frequent in patients who had survived longer than 1 year (25/33; 75.8%). None of the patients died of prostheses-related problems within 1 week. Non-infectious valve failure was more common in patients with bioprostheses than in those with mechanical valves; thromboembolism showed the opposite association. Prosthetic valve infective endocarditis was nearly equal in frequency in both types of valve.     

Anatomic analysis of removed prosthetic heart valves: causes of failure of 33 mechanical valves and 58 bioprostheses, 1980 to 1983

The details of heart valve prosthesis-associated problems are not widely known. This study investigated the etiologies of the failures of 91 valves, 33 mechanical prostheses and 58 bioprostheses, obtained at reoperation (83) or autopsy (eight) at the Brigham and Women's Hospital during the 42-month period from mid- 1980 through 1983, one to 264 months (mean, 72 months) after valve replacement. Analysis was by gross, histologic, radiographic, and microbiologic examination, as well as review of clinical records. Overall causes of failure included paravalvular leak (15 per cent), thrombosis (7 per cent), tissue overgrowth (8 per cent), degeneration or mechanical failure (43 per cent), and endocarditis (19 per cent). Endocarditis and paravalvular leak were equally frequent with mechanical prostheses and bioprostheses. In addition, thrombosis (18 per cent), tissue overgrowth (21 per cent), and structural failure (12 per cent) were all important failure modes for mechanical prostheses. Sterile degeneration was the overwhelming cause of failure for bioprostheses, accounting for the failure of 35 of 58 (60 per cent) of those recovered. Sterile degeneration took several forms: calcification, with or without cuspal tears (27 cases, 47 per cent of bioprostheses; mean, 77 months, range, 44 to 108 months) and cuspal defects without calcification (eight cases, 14 per cent; mean, 59 months, range, eight to 122 months). In general, calcification increased with time after implantation, but the propensity for the mineralization of bioprostheses varied widely among patients. Four torn valves that had been in place for more than six years had radiographically undetectable calcific deposits. The results of this study indicate that paravalvular leak and endocarditis are frequent causes of failure for all valve types. No clear failure mode predominates with mechanical valve prostheses, although some designs have specific inherent limitations. In contrast, degeneration, especially that related to mineralization, is the most important cause of the late failure of contemporary bioprostheses.     

Corynebacterium jeikeium endocarditis: a systematic overview spanning four decades

Skin flora is an important source of microorganisms that cause infective endocarditis. While staphylococcal and beta-hemolytic streptococcal species are well-recognized components of skin flora that can cause infective endocarditis, other skin flora rarely produce endocardial infection. One species of Corynebacterium has received the most attention, Corynebacterium jeikeium. This bacterium, a gram-positive rod that is a strict aerobe, is known to cause mechanical prosthetic valve infection and vancomycin is generally required for treatment of this multidrug-resistant organism. Following treatment of an unusual case of bioprosthetic valve endocarditis due to C. jeikeium, a Medline search for English-language articles published from January 1966 to October 2004 was performed. Reports of C. jeikeium endocarditis cases with culture of either blood or cardiac surgery tissue samples positive for C. jeikeium and with clinical and echocardiographic findings of infective endocarditis were reviewed. Clinical data and results of diagnostic procedures were examined. All 38 patients with C. jeikeium endocarditis reported in the literature had at least one predisposing condition for the development of infective endocarditis. The majority of patients (74%) had involvement of a prosthetic heart valve. The mortality attributed to C. jeikeium endocarditis was 33% and was similar in patients who did and did not undergo valve replacement. This relatively high mortality rate mandates that clinicians be aware of this rare endocardial infection. C. jeikeium is a rare cause of endocarditis and it more commonly infects prosthetic valves. Careful scrutiny is required when C. jeikeium is isolated from a blood culture, particularly in patients with underlying prosthetic cardiac valves.     

Multi-valvular endocarditis

Objective   Seventy-seven cases of native valve infective endocarditis as determined by the Duke criteria, were reviewed to determine the incidence and clinical features of multi-valvular endocarditis.
Methods   Fourteen of 77 patients (18%) had multi-valvular endocarditis most commonly involving the mitral and aortic valves. Staphylococcus aureus (43%) and viridans streptococci (36%) were the most common organisms causing multi-valvular endocarditis.
Results   Definite or probable vegetations were found in 50% of the patients by two-dimensional transthoracic echocardiograph and/or transesophageal echocardiograph, and possible vegetations were detected in 21%. The overall mortality in our series was 21%; 29% underwent valve replacement and 50% were treated medically. The major complications of multi-valvular endocarditis were congestive heart failure (64%), acute renal failure (50%), embolic events (21%), and splenic abscess/infarcts (21%).
Conclusions   Our data suggests complications of multi-valvular endocarditis, compared with uni-valvular endocarditis are similar except for heart failure. Heart failure is statistically more common in multi-valvular endocarditis ( P 0.002).     

Infective endocarditis of bicuspid pulmonary valve

Infective endocarditis of the cardiac valves mainly involves the aortic mitral valves and less frequently the tricuspid valve. Isolated pulmonary valve involvement is extremely rare with few cases reported in literature. We present a case of a 34-year-old female who presented with sudden onset breathlessness and cardiac failure. A complete autopsy showed an uncommon congenital bicuspid pulmonary valve, which was also affected by infective endocarditis.     

Bioprosthetic heart valves: modes of failure

Valve replacement started in 1960, with the surgeon now having a significant variety of prosthetic heart valves from which to choose. These valves are broadly divided into mechanical heart valves (MHV) and bioprosthetic heart valves (BHV). Improvements in the performance and ease of usage of BHV without the need for anticoagulant therapy are among the desired features of BHV and hence the increasingly preferred choice over their mechanical counterparts. However, with increased use the post-implantation complications have become more apparent, and these include: calcification, cusp tears, pannus growth, infective endocarditis, valve thrombosis and other factors specific to valve type. In this review we describe these complications in order to bring awareness among surgeons, clinicians and pathologists. Diagnosis, treatment and preventive measures, if taken in a timely manner, can help reduce their impact and further enhance the quality of life of patients with prosthetic heart valves.     

Fluorescence in situ hybridization to improve the diagnosis of endocarditis: a pilot study

Infective endocarditis is a rare but life-threatening disease associated with high mortality. Early diagnosis of the causative microorganism is critical to patient outcome. However, conventional diagnostic methods are often unsatisfactory in achieving this goal. As a proof of concept, we applied fluorescence in situ hybridization (FISH) for detection and identification of bacteria in histological sections of heart valves. Biopsy specimens from 54 suspected endocarditis patients were obtained during valve surgery and analysed via FISH. Specimens were screened with a probe panel that identifies the most common bacteria implicated in endocarditis. Results were compared with those of culture-based diagnostics and clinical data. Discrepant results were subjected to comparative sequence analysis of PCR-amplified 16S rRNA genes. FISH detected bacteria in 26 of the 54 heart valves. FISH allowed successful diagnosis of infective endocarditis in five of 13 blood culture-negative cases and in 11 of 37 valve culture-negative cases, showing the bacteria within their histological context. This technique allows the simultaneous detection and identification of microorganisms at the species or genus level directly from heart valves and might be a valuable tool for diagnosis of endocarditis.     

The CarboMedics prosthetic heart valve: experience with 180 implants

At Jichi Medical School Hospital, three types of mechanical prosthetic valves (CarboMedics, Omnicarbon, Bicarbon) were used without randomization from 1991 to 2000. A retrospective study of valve replacements done between June 1991 and November 2000 utilizing 180 CarboMedics valves in 145 patients who had not previously undergone prosthetic valve replacement or aortic root and/or arch replacement was conducted to evaluate midterm patient outcomes to assess the future continuous use of CarboMedics valves. Women made up 47.6% of the patients and the mean age was 57.5 years (range 12–80 years). Preoperative New York Heart Association functional class was III or IV in 92.4% (134/145) of patients. Mean follow-up of 4.5 years (range 0–10.0 years) was 95.9% complete, with a total of 628 patient-years (PY). Early (within 30 postoperative days) mortality was 5.5% (8 of 145): 3 from hemorrhage, 3 from nonvalve-related heart failure, 1 from infection, and 1 from arrhythmia. There were 16 late deaths (2.54%/PY): 1 from hemorrhage, 4 from unknown causes/sudden death, 4 from nonvalve-related heart failure, and 7 from other noncardiac causes. A total of 121 patients (83.0%) were alive at the last follow-up, done in November 2000. The linearized death rate was 3.82%/year (including 1.11%/year for valve-related deaths). Linearized death rates from various causes were: bleeding, 0.96%/year; thromboembolism, 1.11%/year; thrombosis, 0.39%/year; perivalvular leak, 0.96%/year; endocarditis, 0%/year; hemolysis, 0%/year; and reoperation, 0.63%/year. No structural valve failure was observed. Comparative early mortality rates of valve replacement without aortic root replacement or arch replacement, excluding repeat valve replacement operations, in our institute, were 3.5% (12/307) for all valve types used contemporaneously, 2.6% (2/76) for Omnicarbon valves, and 2.3% (2/86) for Bicarbon valves. Although the CarboMedics valve had a rather high mortality rate of 5.5% (8/145) compared with the total early mortality rate of 3.5%, the low incidence of valve-related complications might support the continued use of the CarboMedics valve for valve replacement.     

心脏人工机械瓣相关并发症外科治疗初步经验

目的　总结 15例心脏人工机械瓣相关并发症外科治疗初步经验。方法　本组 15例患者中 ,男 7例 ,女 8例 ,年龄 315 9岁 ,平均 (4 5 .5± 8.0 )岁。术前均明确诊断 ,人工机械瓣心内膜炎 4例 ,单纯主动脉瓣周漏 4例 ,单纯二尖瓣周漏 4例 ,单纯主动脉瓣并二尖瓣周漏 2例 ,二尖瓣栓塞 1例。肺水肿 10例 ,充血性心力衰竭 6例。再次手术距首次手术时间间隔 1个月至 72个月 ,平均 (2 1.9± 18.2 )个月。本组在全麻中度低温体外循环下行再次主动脉瓣替换术 4例 ,再次二尖瓣替换术 2例 ,主动脉瓣周漏修补术 2例 ,二尖瓣周漏修补术 5例 ,主动脉瓣和二尖瓣周漏修补术 2例。同期手术包括主动脉右心室交通残余漏修补术 1例 ,三尖瓣成形术 4例 ,主动脉瓣替换术 1例 ,冠状动脉旁路移植术 1例。结果　手术死亡 5例 (33.3% )。术后低心排、多脏器功能衰竭 (3例 )为死亡主要原因。 1例为劈胸骨时损伤主动脉大出血 ,术后深昏迷死亡 ,中毒性休克死亡 1例。存活 10例 ,随访 ,死亡 1例为再次主动脉瓣替换术后半年瓣膜栓塞 ,余 9例心功能明显改善。结论　人工机械瓣膜病外科治疗值得 ,但手术危险性较高     

Autopsy-determined causes of death following heart valve replacement

The pathological findings and the principal cause of death were reviewed in 275 patients with 345 heart valve prostheses. Rheumatic fever necessitated valve replacement in 73% of these patients. Tissue valves bore significantly fewer and scantier thrombi than did the mechanical prostheses. Patients with these two groups of valves showed no significant difference with regard to the incidence of infarction of systemic organs. Patients with prostheses showed infarcts of the spleen, brain, and heart more often than did nonoperated controls with valvular disease. Among the mechanical valves, patients with Starr-Edwards valves showed the highest incidence of fatal thromboembolism. Prosthesis-related problems formed the biggest single cause of death in the 275 patients with valve prostheses. The mechanical valve group, which formed 82% of the total, had prosthesis-related problems as the prime cause of death; in the tissue valve group this complication ranked third in importance after unknown causes and diseases unrelated to valve surgery. Analysis of the valve-related causes of death showed that thrombosis and infection of the prosthesis were more important in the mechanical valves, whereas structural failure was more common with the tissue valves. Prosthesis-related fatal complications were present in 13% of the patients who died within 30 days postoperatively and in 61% of those who died later.     

Paecilomyces javanicus endocarditis of native and prosthetic aortic valve

A 41-year-old diabetic woman developed endocarditis of the aortic valve caused by Paecilomyces javanicus six years after insertion of a porcine mitral valve heterograft. The patient died shortly after aortic valve replacement. Autopsy revealed vegetations of the aortic heterograft, valve ring abscess and ascending aortitis due to Paecilomyces. There was no involvement of the mitral valve heterograft. Lesions due to mycotic emboli were found in the kidneys, spleen, and brain. Cultures of the surgically removed aortic valve and of the kidney at autopsy produced rapid growth of P. javanicus. The gross and microscopic pathologic and cultural characteristics of this organism are described with a review of the literature. Previously reported cases of Paecilomyces endocarditis occurred only in prosthetic heart valves. This is the first known report of P. javanicus endocarditis of a native valve and its prosthetic heart valve heterograft.     

Infective endocarditis in Greece: a changing profile. Epidemiological, microbiological and therapeutic data

The epidemiology, and clinical and microbiological spectrum, of infective endocarditis (IE) in Greece was analysed in a prospective 4-year study in a tertiary hospital and a heart surgery centre in Athens. In total, 101 cases of IE (71 men, 30 women, aged 54.4 +/- 17.1 years) were studied, with a follow-up period of 3 months. Seventy-seven cases were definite and 24 possible; 59 involved native valves (native valve endocarditis; NVE), 31 prosthetic valves (prosthetic valve endocarditis; PVE), of which nine were early and 22 late, and 11 permanent pacemakers (pacemaker endocarditis; PME). There was a predominant involvement of aortic (48/101) and mitral (40/101) valves. Seven patients had rheumatic valvular disease, two had mitral valve prolapse, and eight had a previous history of IE. Thirteen and six patients had undergone dental and endoscopic procedures, respectively. In 13 patients, intravenous catheters were used within the 3 months before diagnosis of IE. There were three intravenous drug users among the patients. Staphylococcus aureus was the most important pathogen, isolated in 22% of cases, followed by viridans streptococci (19%) and coagulase-negative staphylococci (16%). Enterococcus spp. were responsible for 3%, HACEK group for 2%, and fungi for 6% of cases. Viridans streptococci were the leading cause of NVE (29%), Staphylococcus epidermidis of PVE (16%), and S. aureus of PME (54.5%). Six of 22 S. aureus and ten of 16 S. epidermidis isolates were methicillin-resistant. Surgical intervention, including total pacemaker removal, was performed in 51.5% of patients. Overall mortality was 16%, but was 29% with PVE, and was significantly higher with medical than with combined surgical and medical therapy (24.5% vs. 8%). Compared with previous studies, there were changing trends in the epidemiology, microbiology, treatment and prognosis of IE in Greece.     

Ionescu-Shiley bovine pericardial bioprostheses. Histologic and ultrastructural studies.

Studies were done on the structural changes that develop in Ionescu-Shiley valves that are used as replacement heart valves for 4 to 8 years. These changes were compared with those found in similarly used porcine aortic valve (PAV) bioprostheses. A variety of morphologic differences were observed between bovine pericardial valve (BPV) and PAV bioprostheses after orthotopic implantation including: primary tissue failure associated with the use of an alignment suture, thickening of valve leaflet, leaflet tissue delamination, leaflet calcification, and dystrophic alterations of collagen. These findings indicate that valve design criteria directly influence the durability of pericardial valves. However, other factors unique to pericardial tissue also affect the durability and performance of BPVs. These factors include the inability of pericardial tissue to accommodate dynamic stresses; the extensive insudation of plasma proteins and lipids; and the inability to reduce leaflet calcification using agents that effectively mitigate calcification in PAV bioprostheses.     

Ten years of infective endocarditis: a clinicopathologic study

The records of 46 patients with infective endocarditis diagnosed either clinically or post-mortem were analyzed. Twenty-six patients were over 60 years of age. S. aureus was the predominant organism, almost exclusively found in patients with acute endocarditis. Thirty-six patients had pre-existing heart disease, the most common being non-rheumatic valvular calcification and congenital defects. Two thirds of the patients, especially those with aortic valve regurgitation, developed new or progressive heart failure. A correct clinical diagnosis was established in only 30 patients. Twenty-three patients died, the mortality being 71% in acute and 32% in subacute disease. Only one of eight patients with prosthetic valve infection died. Four patients required urgent valve replacement. Early surgical intervention should be considered in patients with uncontrolled heart failure.     

Mycobacterium fortuitum prosthetic valve endocarditis: a case for the pathogenetic role of biofilms

BackgroundProsthetic valve endocarditis presents unique challenges for both diagnosis and treatment. A potential role of biofilm has been hypothesized in the pathogenesis of these infections.MethodsA patient with infective endocarditis involving a stentless (Freestyle) porcine prosthetic aortic valve with annular abscess and paravalvular leak 8 months after implantation is reported.ResultsThe infected valve did not show vegetations or perforations, but histiocytic inflammation was seen along the endocardial surfaces of the valve. Auramine–rhodamine staining revealed many acid-fast organisms associated with the inflammation. There was also an acellular matrix material with ultrastructural features of biofilm. Blood cultures grew Mycobacterium fortuitum, a biofilm-associated microbe.ConclusionsThe role of biofilm in prosthetic valve endocarditis is discussed. The importance of microscopy for prosthetic valves, even when no vegetations are present, is highlighted along with correlation of pathologic findings with culture results.     

Artificial valves “up to date” in Japan

We have many choices when selecting artificial valves for valve replacement surgery. It is necessary to know the characteristics of the various prosthetic valves to make an appropriate decision for each valvular heart disease patient. In this review paper, we describe the features and benefits of the artificial valves available in Japan. Standard and new generation bioprostheses and mechanical prostheses are reviewed. The new technology of the catheter-delivery heart valve is also mentioned in this paper.     

Unusual course of infective endocarditis: acute renal failure progressing to chronic renal failure

Infective endocarditis is an infection of the endocardium that usually involves the valves and adjacent structures. The classical fever of unknown origin presentation represents a minority of infective endocarditis. The presented case was a 21-yearold young lady presenting with acute renal failure and fever to the emergency room. Cardiac auscultation revealed a soft S1 and 4/6 apical holosystolic murmur extended to axilla. Echocardiography showed mobile fresh vegetation under the mitral posterior leaflet. She was diagnosed as having infective endocarditis. Hemodialysis was started with antimicrobial therapy. However, because of the presence of severe mitral regurgitation with left ventricle dilatation and large mobile vegetation, mitral prosthetic mechanical valve replacement was performed. Although treated with antibiotics combined with surgery, renal functions were deteriorated and progressed to chronic renal failure.     

Isolated pulmonary valve replacement: analysis of 27 years of experience

The aim of this study was to investigate the longterm results of isolated pulmonary valve replacement using xenobioprostheses or mechanical valves. Twenty-four cases of isolated pulmonary valve replacement carried out at Kyushu University Hospital between 1977 and 2004 were reviewed. Those undergoing Rastelli's operation were excluded from this study. Bioprostheses were used in 18 patients and mechanical valves in 6. There were no operative deaths. Two patients with mechanical valves needed repeat pulmonary valve replacement due to thrombosed valves. The patients with bioprostheses had no need of repeat replacement postoperatively. The cardiothoracic ratio significantly improved from 60.3% preoperatively to 55.4% postoperatively (P < 0.05), and the New York Heart Association (NYHA) class significantly improved from 2.0 preoperatively to 1.1 postoperatively (P < 0.05). The actuarial survival rate at 15 years was 92.3%. The valve-related event-free ratio at 15 years was 85.7% in the bioprosthesis group and 66.7% in the mechanical valve group, with no significant difference. Isolated pulmonary valve replacement with bioprostheses or mechanical valves can be safely done and showed satisfactory long-term results. The mechanical valve group demonstrated a high ratio of thrombosed valves. A bioprosthesis is recommended for pulmonary valve replacement if a homograft is not available.     

Surgical pathology and etiology of 278 surgically removed mitral valves with pure regurgitation in Thailand.

INTRODUCTION: There are multiple causes of mitral regurgitation. Its etiology includes floppy valve, postinflammatory disease, infective endocarditis, and other disorders. Recently, there has been an increased tendency to remove only portions of the mitral valve, causing difficulty in the determination of etiology. Our objective was to study the pathology and etiology of mitral regurgitation from surgically removed specimens. METHODS: Native mitral valve specimens surgically excised due to mitral insufficiency were examined. Etiology was determined according to macroscopic, microscopic, clinical, and operative findings. RESULTS: Among 278 mitral valve specimens, 43% were classified as floppy valve, 31% as postinflammatory disease (presumably associated with rheumatic fever), 12% as infective endocarditis, and 14% as miscellaneous group. In floppy valves, diffuse myxoid change and chordal rupture were the main findings. In postinflammatory disease, moderate neovascularization and chronic inflammatory cell infiltration were most commonly found. Aschoff bodies were found in two cases. In infective endocarditis, gram-positive cocci were found in 70% of cases. In the miscellaneous group, three cases were related to Marfan syndrome and one case was related to papillary muscle necrosis. In comparison with postinflammatory disease, the posterior leaflet in the floppy valve had a significantly longer basal free-edge length, a more frequent chordal rupture, and an higher mean age of patients. Among completely and partially excised specimens with postinflammatory disease, there were no significant differences in microscopic findings. CONCLUSION: The three most common etiologies in mitral regurgitation were floppy valve, postinflammatory disease, and infective endocarditis. Macroscopic, microscopic, clinical, and operative findings are important in the evaluation of etiology, especially in partially excised specimens.     

Cardiobacterium hominis endocarditis: two cases and a review of the literature

Cardiobacterium hominis, a member of the HACEK group (Haemophilus parainfluenzae, Haemophilus aphrophilus, and Haemophilus paraphrophilus, Actinobacillus actinomycetemcomitans, C. hominis, Eikenella corrodens, and Kingella species), is a rare cause of endocarditis. There are 61 reported cases of C. hominis infective endocarditis in the English-language literature, 15 of which involved prosthetic valve endocarditis. There is one reported case of C. hominis after upper endoscopy and none reported after colonoscopy. Presented here are two cases of C. hominis prosthetic valve endocarditis following colonoscopy and a review of the microbiological and clinical features of C. hominis endocarditis. Patients with C. hominis infection have a long duration of symptoms preceding diagnosis (138±128 days). The most common symptoms were fever (74%), fatigue/malaise (53%), weight loss/anorexia (40%), night sweats (24%), and arthralgia/myalgia (21%). The most common risk factors were pre-existing cardiac disease (61%), the presence of a prosthetic valve (28%), and history of rheumatic fever (20%). Of the 61 cases reviewed here, the aortic valve was infected in 24 (39%) and the mitral valve in 19 (31%) patients. The average duration of blood culture incubation before growth was detected was 6.3 days (range, 2–21 days). Complications were congestive heart failure (40%), central nervous system (CNS) emboli (21%), arrhythmia (16%), and mycotic aneurysm (9%). C. hominis is almost always susceptible to β-lactam antibiotics. Ceftriaxone is recommended by the recently published American Heart Association guidelines. The prognosis of C. hominis native valve and prosthetic valve endocarditis is favorable. The cure rate among 60 patients reviewed was 93% (56/60). For prosthetic valve endocarditis, the cure rate was 16/17 (94%). Valve replacement was required in 27 (45%) cases.