Dominique Grisoli

Management of infective endocarditis: challenges and perspectives

Despite improvements in medical and surgical therapies, infective endocarditis is associated with poor prognosis and remains a therapeutic challenge. Many factors affect the outcome of this serious disease, including virulence of the microorganism, characteristics of the patients, presence of underlying disease, delays in diagnosis and treatment, surgical indications, and timing of surgery. We review the strengths and limitations of present therapeutic strategies and propose future directions for better management of endocarditis according to the most recent research. Novel perspectives on the management of endocarditis are emerging and offer hope for decreasing the rate of residual deaths by accelerating the process of diagnosis and risk stratification, reducing delays in starting antimicrobial therapy, rapid transfer of high-risk patients to specialised medico-surgical centres, development of new surgical methods, and close long-term follow-up.

Mobile Extracorporeal Membrane Oxygenation Unit Expands Cardiac Assist Surgical Programs

BACKGROUND Extracorporeal membrane oxygenation (ECMO) is an effective technique to provide emergency mechanical circulatory or respiratory assistance in critically ill patients. A Mobile Remote Cardiac Assist unit was created to implant ECMO in patients from outside our institution and bring them back in our intensive care unit for follow-up when stabilized. This study was undertaken to evaluate the feasibility and the preliminary results of this procedure. METHODS Between March 2006 and June 2008, 38 consecutive patients with acute cardiac or respiratory failure were implanted with percutaneous ECMO. The logistic concerns, indications, complications, and outcomes of these patients were analyzed. RESULTS There were no logistic or technical problems during the round trip or ECMO implantation. Mean distance from our intensive care unit was 68 km (1 to 230). Maximal time limit between the phone call and implantation was 90 minutes. The indications were fulminant myocarditis, pharmacologic suicide attempt, acute myocardial infarction, postpartum cardiopathy, end-stage cardiomyopathy, with left ventricular ejection fraction of 0.19 ± 0.05 (n = 32), or acute respiratory distress syndrome without cardiac failure (n = 6). Patients received a percutaneous venoarterial femoral ECMO with immediate reperfusion of the limb or venovenous ECMO for isolated lung failure. Seventeen patients (45%) were successfully weaned from ECMO after 9.4 ± 8.7 days. Four patients (11%) were transplanted. One patient was switched to a left ventricular assist device and was then successfully transplanted. Twenty-one patients (55%) survived to hospital discharge. CONCLUSIONS The Mobile Cardiac Assist unit allowed emergency implantation of ECMO support in remote institutions without any logistic or technical problems.

Infective Endocarditis: Prevention, Diagnosis, and Management

Infective endocarditis (IE) is among the most severe infectious disease, the prevention of which has not decreased its incidence. The age of patients and the rate of health care-associated IE have increased as a consequence of medical progress. The prevention strategies have been subjected to an important debate and nonspecific hygiene measures are now placed above the use of antibiotic prophylaxis. Indeed, the level of evidence of antibiotic prophylaxis efficiency is low and the indications of its prescription have been restricted in the recent international guidelines. In cases carrying a high suspicion of IE, efforts should be made to rapidly identify patients with a definite or highly probable diagnosis of IE and to find the causative pathogen to ensure that appropriate treatment, including urgent valvular surgery, begins promptly. Although echocardiography remains the main accurate imaging modality to identify endocardial lesions associated with IE, it can be negative or inconclusive especially in cases of prosthetic valve or other intracardiac devices. Recent studies demonstrated the diagnostic value of other imaging strategies including cardiac computed tomography (CT), positron emission tomography/CT, radiolabelled leukocyte single-photon emission CT/CT, and cerebral magnetic resonance imaging. Novel perspectives on the management of endocarditis are emerging and offer a hope for decreasing the rate of residual deaths by accelerating the processes of diagnosis, risk stratification, and instauration of antimicrobial therapy. Moreover, the rapid transfer of high-risk patients to specialized mediosurgical centres (IE team), the development of new surgical modalities, and close long-term follow-up are of crucial importance.

Reduction in incidence of Q fever endocarditis: 27 years of experience of a national reference center

OBJECTIVES We conducted an observational study to evaluate the impact of our antibioprophylaxis protocols implemented in 2000, on the incidence of Q fever endocarditis diagnosed in our French reference center between 1985 and 2011. METHODS Endocarditis was diagnosed according to modified Duke Criteria, serological and PCR results. Our prophylaxis recommendations consist of a systematic echocardiography and an antibioprophylaxis in patients with acute Q fever and risk factors for developing endocarditis. RESULTS Over the last 27 years, we diagnosed 4231 acute Q fever and 818 endocarditis. Despite a significantly increased number of acute Q fever diagnoses and the use of systematic PCR testing of valves allowing serendipitous Q fever endocarditis diagnoses, we observed a decline of Q fever endocarditis. The number of cases has decreased from 316, which represents 18% of newly diagnosed cases of Q fever between 1998 and 2004, to 225, which corresponds to 11% of the cases diagnosed between 2005 and 2011. CONCLUSION We believe that this decrease was a result of our strategies for prophylaxis. If this assumption is true, we may have prevented more than 150 cases of Q fever endocarditis in France over the past 10 years.

Treatment of Staphylococcus aureus endocarditis with high doses of trimethoprim/sulfamethoxazole and clindamycin—Preliminary report

Infective endocarditis (IE) is still experiencing a high mortality ate even though this rate has been reduced in successive stages hanks to more focused antibiotics and increased indications for ardiac surgery, as is being confirmed in recent studies [1]. Recently, ollowing early surgery the mortality rate at Aix-Marseille Univerité (Marseille, France) fell to 10% [1]. However, a new increase n the number of deaths in our centre appears to be related to ssues of time management and organisation in surgical treatment nd, second, to the increase in the number of septic shocks related o Staphylococcus aureus [2]. In fact, the early (≤3 months) fatalty rate went from 9% (from 2000 to 2006) to 12% (from 2007 P = 0.075. ‡ P < 0.001.

Persistence of DNA in a Cured Patient and Positive Culture in Cases with Low Antibody Levels Bring into Question Diagnosis of Q Fever Endocarditis

ABSTRACT We evaluated the performance of tools for diagnosing Q fever cardiovascular infection. We retrospectively analyzed 162 cardiovascular samples from 125 patients who were tested serologically by immunofluorescence, quantitative PCR (qPCR), 16S rRNA gene amplification, culture, and immunohistochemistry, and we assessed the viability of Coxiella burnetii by measuring the transcription of the 16S rRNA gene. The qPCR technique was significantly more sensitive than 16S rRNA gene amplification (P < 0.0001), cell culture (P = 0.0002), and immunohistochemistry (P < 0.0001). The sensitivity of these techniques was reduced when applied to patients who had been previously treated. The severity of infection appears to be correlated with phase I IgG levels. We report for the first time 4 cases of endocarditis with positive qPCR and/or culture assay result from patients with a low phase I IgG (IgG I) titer (<800), and we have identified the longest (16 years) persistence of DNA described in a heart valve from a patient cured after being previously treated for endocarditis. The active transcription of the 16S rRNA gene was found in 19/59 tested samples, with a positive predictive value of 100% for a positive culture. In conclusion, the diagnosis of Q fever cardiovascular infection should not be excluded in patients with low titers of phase I IgG when they present with valvulopathy. We recommend testing cardiovascular samples using 3 or 4 different biopsy sections by qPCR evaluation for patients with IgG I titers of ≥200.

Rapid Deployment of Aortic Bioprosthesis in Elderly Patients With Small Aortic Annulus

BACKGROUND Aortic valve replacement in elderly patients with a small aortic annulus remains challenging. Patient-prosthesis mismatch (PPM) should be prevented without impacting operative mortality. Hemodynamic benefits resulting from rapid-deployment aortic valve replacement with the Edwards Intuity bioprosthesis for this indication were evaluated. METHODS Elective patients with severe aortic stenosis who required an Edwards Intuity bioprosthesis, size 19 mm and 21 mm, were prospectively included between July 2012 and July 2014. Transthoracic echocardiography was performed preoperatively and at 1-month follow-up. RESULTS Sixty-six consecutive patients (mean age, 78 ± 6.4 years; 54.5% women) were included. The Intuity 19 mm was inserted in 29 patients, and the Intuity 21 mm was inserted in 37 patients. No deaths or aortic annulus ruptures occurred. Mean aortic cross-clamp time was 42.7 ± 18.2 minutes. At the 1-month follow-up, mean New York Heart Association classification was 1.6 ± 0.5 versus 2.2 ± 0.8 (p < 0.001). The mean gradient decreased from 59 ± 17.6 mm Hg to 13.7 ± 4.4 mm Hg (p < 0.001). Mean indexed effective orifice area was 0.77 ± 0.17 cm(2)/m(2) for the Intuity 19 mm and 1.01 ± 0.32 cm(2)/m(2) for the Intuity 21 mm. Twenty-one patients (32%) had a moderate PPM (indexed effective orifice area < 0.85 cm(2)/m(2)), and 10 patients (15%) had a severe PPM (indexed effective orifice area < 0.65 cm(2)/m(2)). The mean gradient was 15.1 ± 3.5 mm Hg and 16.9 ± 4.9 mm Hg in the moderate PPM group and severe PPM group, respectively (p = 0.3). The left ventricular mass index dramatically decreased from 153.2 ± 32.7 g/m(2) to 118.4 ± 20.2 g/m(2) (p < 0.001), and only 1 patient (1.5%) had a periprosthetic regurgitation greater than 1. CONCLUSIONS Regarding the low rate of severe PPM and the early regression of left ventricular mass, these preliminary studies indicate the potential benefit of the Intuity bioprosthesis in patients with a small aortic annulus. Midterm results should be evaluated.

Value of CMR in quantification of paravalvular aortic regurgitation after TAVI.

AIMS To assess the value of cardiac magnetic resonance (CMR) using phase-contrast velocity mapping for paravalvular aortic regurgitation (PAR) quantification. METHODS AND RESULTS All patients undergoing transcatheter aortic valve implantation (TAVI) in our centre between November 2012 and August 2013, without CMR-contraindication were included. PAR severity was assessed 5 days after TAVI using: transthoracic echocardiography (TTE) and CMR [regurgitant volume (RV), regurgitant fraction (RF)]. Aortic regurgitation (AR) index was obtained during TAVI. Thirty of 51 patients who underwent TAVI were included (COREVALVE, n = 10; or EDWARDS SAPIEN XT, n = 20). At TTE, PAR was mild in 22, moderate in 3, and severe in 5 patients. Reliable phase-contrast images were acquired at the sino-tubular junction for SAPIEN and at the tubular portion of the ascending aorta for COREVALVE. The reproducibility of CMR was high (coefficient of correlation = 0.99 for intra- and inter-operator variability). At CMR, RV, and RF were significantly (P < 0.0005) correlated with AR severity at TTE, with mean RF values at 9.2 ± 7.6% in mild, 20.3 ± 4.2% in moderate, and 46.8 ± 10.8% in severe PAR. A cut-off value of RF < 14% at CMR accurately discriminated mild from moderate/severe (sensitivity: 100%, specificity: 82%). The mean AR index was 29.4 ± 6 for mild and 13.8 ± 5 for moderate/severe PAR. Three patients had a RF > 14% and a low AR index <25 despite a mild PAR at TTE, suggesting an underestimation at TTE. CONCLUSION CMR is a reproducible, accurate, and reliable method to assess PAR severity. CMR may allow correcting an underestimation at TTE when AR index is doubtful.

A deadly aversion to pork.

Unite de Recherche sur les Maladies Infectieuses et Tropicales Emergentes, Faculte de Medecine, Universite de la Mediterranee, Marseille, France (Prof P-E Fournier MD, H Lepidi MD, Prof D Raoult MD); Pole de Maladies Infectieuses (Prof P-E Fournier MD, J-P Casalta MD, Prof D Raoult MD), Service de Cardiologie (F Thuny MD, Prof G Habib MD), Laboratoire d’Anatomo-Pathologie (H Lepidi MD), Service de Chirurgie Cardiaque (D Grisoli MD), and Service de Medecine Interne (Prof P-J Weiller MD), Hopital de la Timone, Marseille, France; and Laboratoire d’Immunologie, Hopital de la Conception, Marseille, France (J Vitte MD)

DNA Persistence and Relapses Questions on the Treatment Strategies of Enterococcus Infections of Prosthetic Valves

We used amplification of the 16S rRNA gene followed by sequencing to evaluate the persistence of bacterial DNA in explanted heart valve tissue as part of the routine work of a clinical microbiology laboratory, and we analyzed the role of this persistence in the relapses observed in our center. We enrolled 286 patients treated for infective endocarditis (IE) who had valve replacement surgery and were diagnosed according to the modified Duke’s criteria described by Li et al. from a total of 579 IE cases treated in our center. The patients were grouped based on the infecting bacteria, and we considered the 4 most common bacterial genus associated with IE separately (144 were caused by Streptococcus spp., 52 by Enterococcus spp., 58 by Staphylococcus aureus and 32 by coagulase-negative Staphylococcus). Based on our cohort, the risk of relapse in patients with enterococcal prosthetic valve infections treated with antibiotics alone was 11%. Bacterial DNA is cleared over time, but this might be a very slow process, especially with Enterococcus spp. Based on a comprehensive review of the literature performed on Medline, most reports still advise combined treatment with penicillin and an aminoglycoside for as long as 4–6 weeks, but there has been no consensus for the treatment of enterococcal infection of prostheses in IE patients.