Early and mid–term results of the Shelhigh stentless bioprosthesis in patients with active infective endocarditis

Summary Aims This study investigated the early and mid–term results following valve replacement with the new Shelhigh^? stentless bioprosthesis made entirely of biological material in patients with active infective endocarditis (AIE). Material and methods Between 02/2000 and 12/2004, 164 patients (n = 122 men, mean age 59, 18–85 years) received implantation of an AIE Shelhigh^? stentless bioprosthesis in the aortic, mitral, tricuspid or pulmonary position. A total of 119 patients (72.6%) had native AIE and 45 (27.4%) prosthetic AIE. A large proportion of the patients reached the operating room in a condition of cardiac decompensation: 37 (22.6%) patients were intubated, 40 (24.4%) had protracted septic shock and 41 (25.0%) required intensive catecholamine treatment. Surgery was regarded as urgent in 94 patients (57.4%) and was performed as an emergency procedure in 70 (42.6%). The mean follow–up time is 1.5 ± 0.11 years (range, 5 months to 5.2 years). Echocardiographic follow–up examinations were performed early postoperatively and after 12 months. Results In terms of the operative indication, we found a highly significant difference in the survival rate between patients who were operated on urgently vs in an emergency. In patients who died within 30 days, the main cause of death was septic multiorgan failure (67.6%). Only three patients required reoperation due to reinfection of the Shelhigh^? bioprostheses; this represents a reinfection rate of 1.8% in relation to the whole cohort. The postoperative echocardiographic examinations showed the Shelhigh^? valves to have very good hemodynamics without relevant pressure gradients. Conclusion Our experience in the use of Shelhigh^? bioprostheses in patients with native and prosthetic endocarditis show the early and mid–term results, in particular the low reinfection rate and the good hemodynamics, to be comparable with the results achieved using homografts. Since these prostheses are readily available and their implantation straightforward, they are increasingly being used in patients with endocarditis. These promising results need to verified in the long term. This paper was presented at a lecture held at the 71^st annual meeting of the German Society for Cardiology, Mannheim, 31. March—2. April 2005. Disclosure Form: The following study discloses my relationship with any corporate sponsor that might relate in some way to the subject presented.     

Experimental staphylococcal endocarditis and aortitis

Summary The initial colonization, byStaphylococcus aureus, of the catheter damaged aortic valve and aorta of the rabbit, was examined by light and electron microscopy at 15 min, 3 h and 24 h post inoculation (PI). At 15 min PI, the majority of bacteria (80%) were located on the lateral surfaces of the thrombic vegetations while 20% were attached directly to the connective tissue of the aortic valve and aorta in areas where the endothelial lining was disrupted. By 3 h the bacteria on the thrombic vegetations were covered by fibrin. At this time, the bacteria both within the vegetations and on the surface of the vasculature were undergoing multiplication to form small groups. The precipitation of thrombus around the bacteria attached to the surface of the aorta to form microscopic infected vegetations had occurred by 24 h PI. The colonizing bacteria did not elicit any phagocytic response. The colonization of the cardiovasculature byStaph. aureus did not necessarily require pre-existing vegetations.     

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.     

Infective endocarditis in patients who have undergone transcatheter aortic valve implantation: a review

BackgroundTranscatheter aortic valve implantation (TAVI) has been approved for the treatment of severe aortic stenosis since 2008 and recent trials have shown that TAVI is at least non-inferior to surgical aortic valve replacement (SAVR) with regards to short-term efficacy and safety in patients across all surgical risk profiles. Prosthetic valve endocarditis of the transcatheter heart valve is a feared complication; data on the risk of infective endocarditis (IE) subsequent to TAVI are now gradually emerging.ObjectivesWe set forth to conduct a review of the incidence, diagnosis, microbial aetiologies, prevention, outcome and management of TAVI-IE.SourcesFrom the MEDLINE database we included a total of 12 observational studies and five studies of long-term results from randomized controlled trials.ContentThe incidence of TAVI-IE was reported to be between 0.7% and 3.0% per person-year. The most common microbes were reported to be enterococci, Staphylococcus aureus, streptococci and coagulase-negative staphylococci. International guidelines on prevention strategies of IE recommend good sanitary conditions including cutaneous care, good oral hygiene and good care of dialysis catheters. Antibiotic prophylaxis is recommended by guidelines prior to dental procedures in patients with TAVI; however, evidence is sparse. The majority of the patients included in this review with TAVI-IE had an indication for surgical intervention due to IE (50.0% or more); however, only a small subset of the patients underwent surgery (16.4% or less). The in-hospital mortality was around 25%, i.e. of the same order of magnitude as in prosthetic valve IE in general, but varied substantially between studies (from 11% to 64%).ImplicationsThe US Food and Drug Administration's approval of TAVI in patients at low surgical risk may change the characteristics of patients with TAVI, which may influence the incidence, management, and outcome of patients with TAVI-IE.     

封堵器植入后感染性心内膜炎的初步认识及诊治进展

经导管封堵术主要用于治疗先天性心脏病间隔缺损,也用于其他心内或心外异常分流,如瓣膜置换术后瓣周漏。封堵器植入后感染性心内膜炎(IE)非常罕见,资料较完整者仅有18例报道,但是一旦发生则非常严重,随着经皮封堵装置临床应用的日益广泛,该类并发症须引起足够重视,甚至对封堵术前、术中及术后预防性应用抗生素方案也可能需要重新评价。本文对封堵器植入后IE的初步认识及诊治进展进行综述。     

Association of Bartonella spp bacteremia with Chagas cardiomyopathy,endocarditis and arrythmias in patients from South America

Infection with Bartonella spp may cause cardiac arrhythmias, myocarditis and endocarditis in humans. The aim of the present study was to evaluate a possible association between Bartonella spp bacteremia and endocarditis, arrhythmia and Chagas cardiomyopathy in patients from Brazil and Argentina. We screened for the presence of bacterial 16S rRNA in human blood by PCR using oligonucleotides to amplify a 185-bp bacterial DNA fragment. Blood samples were taken from four groups of subjects in Brazil and Argentina: i) control patients without clinical disease, ii) patients with negative blood-culture endocarditis, iii) patients with arrhythmias, and iv) patients with chronic Chagas cardiomyopathy. PCR products were analyzed on 1.5% agarose gel to visualize the 185-bp fragment and then sequenced to confirm the identity of DNA. Sixty of 148 patients (40.5%) with cardiac disease and 1 of 56 subjects (1.8%) from the control group presented positive PCR amplification for Bartonella spp, suggesting a positive association of the bacteria with these diseases. Separate analysis of the four groups showed that the risk of a Brazilian patient with endocarditis being infected with Bartonella was 22 times higher than in the controls. In arrhythmic patients, the prevalence of infection was 45 times higher when compared to the same controls and 40 times higher for patients with Chagas cardiomyopathy. To the best of our knowledge this is the first report of the association between Bartonella spp bacteremia and Chagas disease. The present data may be useful for epidemiological and prevention studies in Brazil and Argentina.     

Changing spectrum of infective endocarditis in India: An 11-year experience from an academic hospital in North India

ObjectiveSeveral studies have demonstrated a shift in the spectrum of infective endocarditis (IE) in the developed world. We aimed to investigate whether demographic and microbiologic characteristics of IE have changed in India.DesignA retrospective analysis of patients with in north India between 2010 and 2020.MethodsThe clinical and laboratory profiles of 199 IE admitted to an academic hospital patients who met the modified Duke criteria for definite IE were analysed.ResultsThe mean age was 34 years, and 84% were males. The main predisposing conditions were injection drug use (IDU) (n = 71, 35.7%), congenital heart disease (n = 46, 21.6%), rheumatic heart disease (n = 25, 12.5%), and prosthetic device (n = 19, 9.5%). 17.1% of patients developed IE without identified predispositions. Among 64.3% culture-positive cases, the most prevalent causative pathogens were Staphylococcus aureus (46.1%), viridans streptococci (7.0%), enterococci (6.0%), coagulase-negative staphylococci (5.5%), gram negative bacilli (5.5%), polymicrobial (5.5%), and Candida (1.0%). The tricuspid (30.3%), mitral (25.6%), and aortic (21.6%) valves were the most common sites of infection, and 60.3% had large vegetations (>10 mm). Systemic embolization occurred in 55.3% of patients at presentation. Cardiac surgery was required for 13.1%. In-hospital mortality was 17.1% and was associated with prosthetic devices (p-value, 0.001), baseline leucocytosis (p-value, 0.036) or acute kidney injury (p-value, 0.001), and a microbial etiology of gram negative bacilli or enterococci (p-value, 0.005).ConclusionIDU is now the most important predisposition for IE in India, and S. aureus has become the leading cause of native valve endocarditis with or without IDU.