Computed tomography with positron emission tomography is more useful in local than systemic infectious process related to cardiac implanted electrotherapy device: a prospective controlled multicenter diagnostic intervention PET-Guidance Trial.

Assess the diagnostic value of 18-F FDG PET/CT in cardiac implantable electronic devices (CIED) infections in facilitating diagnostic process and optimizing decision-making process.Study group (n = 21) patients with initial suspected diagnosis of CIED-related infection or fever of unknown origin and patients referred for device removal due to infection. Control group (n = 13) patients with implanted CIED, who underwent PET/CT due to other non-infectious indications and had no data for infectious process in follow-up.PET/CT scan showed pocket infection in 12 patients (including 1 in whom infection was not finally diagnosed-the examination was performed early after the implantation procedure-1.5 months), increased tracer uptake in intravascular lead part in 3 patients, and increased uptake in intracardiac part in 5 patients.We found that sensitivity, specificity, positive predictive value, and negative predictive value of the diagnosis made by PET/CT in generator pocket infection was 91.7%, 70%, 78.6%, 87.5% and in lead-dependent intracardiac infection 100%, 47.1%, 35.7%, 100% respectively. PET/CT scan enabled reclassification of diagnosis from possible to definite CIED-related infection in 6 out of 9 patients, and to excluded in 3 out of 9.Establishing diagnosis of device related infections may be challenging due to non-specific symptoms. Incorporation of PET/CT scan in the diagnostic schema can improve accuracy and timing of the diagnosis and help to assess the extent of infection. PET/CT is more useful in local than systemic infectious process related to cardiac implanted electrotherapy device.Trial registration Consent of the bioethics committee nr IK-NP.-0021-85/1465/14. Registration in the www.clinicaltrials.gov database: NCT02196753.

Advantages of exercise echocardiography in comparison to dobutamine echocardiography in the diagnosis of coronary artery disease in hypertensive subjects.

OBJECTIVE: The aim of the study was to compare the efficacy and safety of two stress echocardiography methods, exercise and dobutamine, in the diagnosis of coronary artery disease in hypertensive patients with angina. PATIENTS AND METHODS: A total of 197 treated hypertensive patients, age 53 +/- 9 years (65 women) with no history of myocardial infarction referred for coronary angiography were prospectively investigated with exercise electrocardiography (ECG), exercise and dobutamine echocardiography. RESULTS: Sensitivity of the exercise ECG, exercise echocardiography and dobutamine echocardiography did not differ (77%, 82% and 75%). Negative predictive value of exercise ECG was significantly lower than exercise echocardiography (64% vs 79%, P < 0.01). Specificity and positive predictive value of exercise ECG were markedly lower than exercise and dobutamine echocardiography (57%, 96%, 98% and 72%, 97%, 98%, P < 0.0001 for both stress echocardiography vs ECG). Specificity and sensitivity of diagnostic methods were not influenced by the presence of echocardiographic left ventricular hypertrophy. Dobutamine infusion in comparison to exercise was more often associated with substantial arterial blood pressure rise or fall (7% vs 2%, P < 0.05) and with simple ventricular ectopy (15,7% vs 6,1%, P < 0.05). CONCLUSIONS: In hypertensive patients with the symptoms of angina, both stress echo methods are significantly more specific than the exercise ECG test. Maximal exercise is associated with less frequent side effects than infusion of dobutamine, so exercise echocardiography may be preferred in the diagnosis of angina in hypertensive patients.

The Staphylococcus aureus lrgAB operon modulates murein hydrolase activity and penicillin tolerance.

Previous studies in our laboratory have shown that the Staphylococcus aureus LytSR two-component regulatory system affects murein hydrolase activity and autolysis. A LytSR-regulated dicistronic operon has also been identified and shown to encode two potential membrane-associated proteins, designated LrgA and LrgB, hypothesized to be involved in the control of murein hydrolase activity. In the present study, a lrgAB mutant strain was generated and analyzed to test this hypothesis. Zymographic and quantitative analysis of murein hydrolase activity revealed that the lrgAB mutant produced increased extracellular murein hydrolase activity compared to that of the wild-type strain. Complementation of the lrgAB defect by providing the lrgAB genes in trans restored the wild-type phenotype, indicating that these genes confer negative control on extracellular murein hydrolase activity. In addition to these effects, the influence of the lrgAB mutation on penicillin-induced lysis and killing was examined. These studies demonstrated that the lrgAB mutation enhanced penicillin-induced killing of cells approaching the stationary phase of growth, the time at which the lrgAB operon was shown to be maximally expressed. This effect of the lrgAB mutation on penicillin-induced killing was shown to be independent of cell lysis. In contrast, the lrgAB mutation did not affect penicillin-induced killing of cells growing in early-exponential phase, a time in which lrgAB expression was shown to be minimal. However, expression of the lrgAB operon in early-exponential-phase cells inhibited penicillin-induced killing, again independent of cell lysis. The data generated by this study suggest that penicillin-induced killing of S. aureus involves a novel regulator of murein hydrolase activity.

Real-time volumetric echocardiography: the technology and the possibilities.

The heart is a dynamic organ with complexities in its shape. As such, it places special demands on three-dimensional techniques for reconstruction. Real-time volumetric echocardiography, which is based on phased array and parallel processing principles to enhance line density within a scan volume, provides rapid image acquisition. We introduce the principle, potential clinical importance, current limitations, and future of volumetric imaging methods.

Resolution of an aortic mobile mass with anticoagulation without evidence of arterial embolism.

The prognostic significance of aortic mobile debris detected by transesophageal echocardiography (TEE) in patients without history of embolism has not been established. A mobile aortic arch mass was found by TEE in a 59-year-old man with coronary artery disease, and with rheumatic mitral valve disease, and with no embolic symptoms. The patient was anticoagulated for 6 weeks and the mass was no longer seen on repeated TEE. He had no embolic symptoms during 9 months of follow-up. Different therapeutic approaches to mobile aortic debris are discussed and anticoagulant treatment of asymptomatic cases is advocated.