16S rDNA PCR for the aetiological diagnosis of culture-negative infective endocarditis.

INTRODUCTION: Culture-negative infective endocarditis (IE) accounts for 7-31% of all cases. Metagenomics has contributed to improving the aetiological diagnosis of IE patients undergoing valve surgery. We assessed the impact of 16S ribosomal DNA gene polymerase chain reaction (16S rDNA PCR) in the aetiological diagnosis of culture-negative IE. METHODS: Between January 2016 and January 2020, clinical data from culture-negative IE patients were reviewed retrospectively. Identification of bacteria was performed using 16S rDNA PCR in heart valve specimens. RESULTS: 36 out of 313 patients (12%) with culture-negative IE had their valve tissue specimens submitted for 16S rDNA PCR. 16S rDNA PCR detected and identified bacterial nucleic acid in heart valve tissue significantly more frequently compared to valve culture alone 25(70%) vs 5(12%); p < 0.05. Mean age was 57 years (SD 18) and 80% were male. Native and aortic valve were involved in 76% and 52% of cases, respectively. Streptococcus spp. (n 15) were the most commonly detected organisms, followed by bacteria of the HACEK group (Haemophilus parainfluenzae 2, Aggregatibacter actinomycetemcomitans 1), nutritionally variant streptococci (Abiotrophia defectiva 2), and one each of Staphylococcus aureus, Corynebacterium pseudodiphtheriticum, Helcococcus kunzii, Neisseria gonorrhoeae, Tropheryma whipplei. CONCLUSION: 16S rDNA PCR may be a useful diagnostic tool for the identification of the causative organism in culture-negative IE. Efforts towards a shorter turnaround time for results should be consider and further studies assessing the clinical impact of this technique in culture-negative IE are needed.

Diagnostic value of 18F-FDG PET/CT in infective endocarditis.

INTRODUCTION: 18F-fluorodeoxyglucose positron emission tomography (18F-FDG-PET/CT) is not routinely recommended for the diagnosis of infective endocarditis (IE) due to the lack of clinical impact. MATERIALS AND METHODS: Between January 2016 and January 2020, clinical data from patients with a possible diagnosis of IE were reviewed retrospectively to evaluate the value of 18F-FDG-PET/CT in the diagnosis of IE. 18F-FDG PET/CT scan was performed as an additional diagnostic tool in possible IE when echocardiography was inconclusive or in patients with definite IE to identify extracardiac complications. Cases were classified according to modified Duke criteria as rejected, definite or possible. RESULTS: 313 patients with suspected IE were included. 72 (23%) patients underwent 18F-FDG PET/CT. 18F-FDG PET/CT resulted in a reclassification of Duke criteria in 29/72 (40%) patients, from "possible" to "definite" (n, 10) and to "rejected" (n, 19). Patients who benefited from a Duke criteria reclassification following 18F-FDG PET/CT were more frequently classified as possible IE at inclusion or had a non-conclusive baseline echocardiography (100% vs 58%; p 0.001) and had more likely a prosthetic metallic valve replacement (59% vs 21%; p 0.001). Abnormal perivalvular uptake was identified in 46 patients (71% prosthetic vs 50% native; p 0.118). 18F-FDG PET/CT identified extracardiac uptake consistent with septic emboli in 14/72 (19%) patients. In addition, extracardiac uptake indicative of an alternative diagnosis was identified in 5 patients (2% prosthetic vs 17% native; p 0.039). CONCLUSION: The use of 18F-FDG-PET/CT has shown to be useful in the diagnosis of IE, particularly in prosthetic IE and may provide additional value in the detection of septic emboli and/or the identification of an alternative diagnosis different from IE.

Time-trend analyses of bleeding and mortality after primary percutaneous coronary intervention during out of working hours versus in-working hours: an observational study of 11 466 patients.

BACKGROUND: Primary percutaneous coronary intervention (PPCI) is the treatment of choice for ST-segment-elevation myocardial infarction. Resources are limited during out of working hours (OWH). Whether PPCI outside working hours is associated with worse outcomes and whether outcomes have improved over time are unknown. METHODS AND RESULTS: We analyzed 11 466 patients undergoing PPCI between 2004 and 2011 at all 8 tertiary cardiac centers in London, United Kingdom. We defined working hours as 9 am to 5 pm (Monday to Friday). We analyzed in-hospital bleeding and all-cause mortality ≤3 years, comparing OWH versus in-working hours. A total of 7494 patients (65.3%) were treated during OWH. Multivariable analyses demonstrated that PPCI during OWH was not a predictor for bleeding (odds ratio, 1.47; 95% confidence interval [CI], 0.97-2.24; P=0.071) or 3-year mortality (hazard ratio, 1.11; 95% CI, 0.94-1.32; P=0.20). This was confirmed in propensity-matched analyses. Time-stratified analyses demonstrated that PPCI during OWH was a predictor for bleeding (odds ratio, 2.00; 95% CI, 1.06-3.80; P=0.034) and 3-year mortality during 2005 to 2008 (hazard ratio, 1.23; 95% CI, 1.00-1.50; P=0.050), but this association was lost during 2009 to 2011. During 2005 to 2008, transradial access was predominantly used during in-working hours and PPCI during OWH was predictive of reduced transradial access use (odds ratio, 0.83; 95% CI, 0.71-0.98; P=0.033), but this association was lost during 2009 to 2011. CONCLUSIONS: In this study of unselected patients with ST-segment-elevation myocardial infarction, PPCI during OWH versus in-working hours had comparable bleeding and mortality. Time-stratified analyses demonstrated a reduction in adjusted bleeding and mortality during OWH over time. This may reflect the improved service provision, but the increased adoption of transradial access during OWH may also be contributory.

Complications of transcatheter aortic valve implantation: avoidance and management.

Transcatheter aortic valve implantation (TAVI) has taken the world of cardiovascular therapies by storm. The possibility of implanting aortic valves without recourse to sternotomy or cardiopulmonary bypass has been embraced by cardiologists, surgeons and patients alike as a revolution in management. First performed in 2002 by Alain Cribier, the technique has exploded into common use during the last three years, such that over 20,000 implants have now been undertaken worldwide. This article discusses complications of TAVI, their avoidance and management.