Clinical performance of Rb-82 myocardial perfusion PET and Tc-99m-based SPECT in patients with extreme obesity.

BACKGROUND: We evaluated the performance of stress imaging with technetium-99m-labeled tetrofosmin single-photon emission computed tomography (SPECT) and rubidium-82 positron emission tomography (PET) in patients with extreme obesity, defined as body mass index ≥40 kg/m2. METHODS: We identified patients with extreme obesity who underwent angiography in our center and either stress SPECT or PET within the previous six months. Cohorts of patients with extreme obesity and a <5% pretest likelihood of CAD who underwent SPECT (N = 25) or PET (N = 25) were also included. RESULTS: In total, 108 patients who underwent SPECT (N = 57) or PET (N = 51) were identified. Scan interpretation was classified as definitely normal or abnormal in 83.3% of PET and 60.5% of SPECT scans, respectively (P < .01). PET demonstrated higher diagnostic accuracy and normalcy rate. PET was found to have higher specificity for the pooled cohort. Similar findings were observed using stenosis cut-offs of ≥50% and ≥70%. CONCLUSIONS: In patients with extreme obesity, PET enabled more definitive scan interpretation with less artifact compared to SPECT. PET provided higher diagnostic accuracy and specificity in the detection of obstructive coronary artery disease.

Lead-Specific Features Predisposing to the Development of Tricuspid Regurgitation After Endocardial Lead Implantation.

BACKGROUND: Endocardial lead in the right ventricle is recognized as a cause for tricuspid regurgitation (TR), but the mechanism remains elusive. We sought to evaluate lead-specific features on the development of TR after endocardial lead implantation. METHODS: This was a prospective single-center study. The patients underwent 2-dimensional echocardiograms before endocardial lead implantation and at follow-up visits at 4 to 6 weeks, 6 months, and 12 months. We assessed the position of the endocardial lead at the tricuspid annulus by 3-dimensional echocardiography, the tricuspid leaflet interference by the endocardial lead by both 2- and 3-dimensional echocardiography, and the degree of lead slack radiologically. Patient characteristics and lead-related factors were evaluated in the prediction of new or worse TR by univariable and multivariable analyses. RESULTS: New or increased TR was detected in 38 of 128 patients at the 12-month follow-up. The postero-septal commissure was the most common lead position, and tricuspid leaflet interference detected in 21 patients was associated with a noncommissural lead position. The implantation of an implantable cardioverter defibrillator lead was not associated with new TR compared with the implantation of a pacemaker lead. Tricuspid leaflet interference (P < 0.0001), but not lead position or lead slack, was the only lead-specific factor associated with the development of TR. CONCLUSION: After right ventricle endocardial lead implantation, leaflet interference determined by echocardiography, but not the nature of the lead, the lead position at the tricuspid annulus, and the radiological lead slack, predicted TR development at 1 year postimplantation.

CONTEXTE: Il est établi que la présence d'une sonde endocavitaire dans le ventricule droit est une cause de régurgitation tricuspide (RT), mais le mécanisme en cause n'est pas encore bien compris. Nous avons tenté d'évaluer la corrélation entre certaines caractéristiques des sondes et l'apparition d'une RT secondaire à l'implantation d'une sonde endocavitaire. MÉTHODOLOGIE: Il s'agit d'une étude prospective menée dans un seul centre. Une échocardiographie bidimensionnelle a été réalisée avant la mise en place d'une sonde endocavitaire, ainsi qu'aux visites de suivi menées 4 à 6 semaines, 6 mois et 12 mois après l'intervention. Nous avons évalué la position de la sonde endocavitaire par rapport à l'anneau tricuspidien par échocardiographie tridimensionnelle, l'interférence de la sonde avec la valve tricuspide par échocardiographie bidimensionnelle et tridimensionnelle, et le degré de liberté de mouvement de la sonde par radiographie. Les caractéristiques des patients et les facteurs liés à la sonde ont été pris en compte dans la prédiction du risque de RT nouvelle ou d'aggravation d'une RT existante au moyen d'analyses univariées et multivariées. RÉSULTATS: Une RT nouvelle ou aggravée a été détectée au suivi à 12 mois chez 38 des 128 patients. Dans la plupart des cas, la sonde se trouvait à la commissure postéroseptale; chez 21 patients, une interférence avec la valve tricuspide a été détectée alors que la sonde ne se trouvait pas à la commissure. La mise en place d'une sonde de défibrillateur implantable n'a pas été associée à l'apparition d'une RT, comparativement à l'implantation d'une sonde de stimulateur cardiaque. L'interférence avec la valve tricuspide (p < 0,0001) était le seul facteur lié à la sonde associé à l'apparition d'une RT; aucun lien n'a été établi avec la position et le degré de liberté de mouvement de la sonde. CONCLUSION: Après la mise en place d'une sonde endocavitaire dans le ventricule droit, l'interférence avec la valve tricuspide établie par échocardiographie permettait de prédire l'apparition d'une RT dans l'année suivant la mise en place de la sonde sans égard au type de sonde, à sa position par rapport à l'anneau tricuspidien ou à la liberté de mouvement détectée par radiographie.

Molecular Imaging for the diagnosis of infective endocarditis: A systematic literature review and meta-analysis.

BACKGROUND: Infective endocarditis (IE) is a serious, potentially life-threatening condition. Currently, the modified Duke criteria is used to assist with the diagnosis of IE, but it can still remain difficult. Growing data supports the potential use of molecular imaging to assist in the diagnosis of IE. Our objective was to understand the potential utility of 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography-computed tomography (PET-CT), 67Ga citrate and radiolabeled white blood cell (WBC) scintigraphy in the diagnosis of IE. METHODS AND RESULTS: A systematic review of the literature and meta-analysis on the use of all 3 modalities in IE was conducted. The literature search identified 2753 articles. A total of 14 studies met the inclusion criteria (10 for 18F-FDG, 3 for WBC and 1 for both modalities). No 67Ga citrate study met the inclusion criteria. Pooled sensitivity of 18F-FDG studies with adequate cardiac preparation for the diagnosis of IE was 81% (95% CI, 73%-86%) and pooled specificity was 85% (95% CI, 78%-91%). There was good overall accuracy with an area under the curve (AUC) of 0.897. Pooled sensitivity of WBC for the diagnosis of IE was 86% (95% CI, 77%-92%) and pooled specificity was 97% (95% CI, 92%-99%). The overall accuracy of WBC was excellent with an AUC of 0.957. CONCLUSIONS: Both 18F-FDG and WBC have good sensitivity, specificity and accuracy for the diagnosis of IE. Both modalities are useful in the investigation of IE, and should be considered in cases where the diagnosis is uncertain.

Cardiac Computed Tomography: Before and After Cardiac Surgery.

Cardiac computed tomography angiography (CCTA) is a noninvasive imaging technique that has been rapidly adopted into clinical practice. Over the past decade, technological advances have improved CCTA accuracy, and there is an increasing amount of data supporting its prognostic value in the assessment of coronary artery disease. Recently, "appropriate use criteria" has been used as a tool to minimize inappropriate testing and reduce patient exposure to unnecessary risk and inconclusive studies. This review will summarize the appropriate uses of CCTA in patients before and after cardiac surgery. Although the most common indication for CCTA is assessment of patency of native coronary arteries, other potential perioperative uses (eg, assessment of congenital heart disease, valvular heart disease, pericardial disease, myocardial disease, cardiac anatomy, bypass grafts, aortic disease, and cardiac masses) will be reviewed.

Positron Emission Tomography and Single-Photon Emission Computed Tomography Imaging in the Diagnosis of Cardiac Implantable Electronic Device Infection: A Systematic Review and Meta-Analysis.

BACKGROUND: The use of cardiac implantable electronic devices (CIED) is increasing, and their associated infections result in significant morbidity and mortality. The introduction of better cardiac imaging techniques could be useful for diagnosing this condition and guiding therapy. Our objective was to systematically assess the diagnostic accuracy of Fluor-18-fluorodeoxyglucose positron emission tomography and computed tomography, labeled leukocyte scintigraphy (LS), and Gallium-67 citrate scintigraphy for the diagnosis of CIED infection. METHODS AND RESULTS: A systematic review of the literature and meta-analysis on the use of all 3 modalities in CIED infection were conducted. Pooled sensitivity, specificity, and summary receiver operating characteristic curves of each imaging modalities were determined. The literature search identified 2493 articles. A total of 13 articles (11 studies for 18F-FDG PET-CT and 2 for LS), met the inclusion criteria. No studies for 67Ga citrate scintigraphy met the inclusion criteria. The pooled sensitivity of 18F-FDG PET-CT for the diagnosis of CIED infection was 87% (95% CI, 82%-91%) and pooled specificity was 94% (95% CI, 88%-98%). The summary receiver operating characteristic curve analysis demonstrated good overall accuracy, with an area under the curve of 0.935. There were insufficient data to do a meta-analysis for LS, but both studies reported sensitivity above 90% and specificity of 100%. CONCLUSIONS: Both 18F-FDG PET-CT and LS yield high sensitivity, specificity, and accuracy, and thus seem to be useful for the diagnosis of CIED infection, based on robust data for 18F-FDG PET-CT but limited data for LS. When available,18F-FDG PET-CT may be preferred.

Endovascular cooling catheter related thrombosis in patients undergoing therapeutic hypothermia for out of hospital cardiac arrest.

BACKGROUND: Therapeutic hypothermia improves neurologic outcome and survival in patients following out-of-hospital cardiac arrest (OHCA). Endovascular cooling devices are commonly used to rapidly achieve and maintain hypothermia. The use of these devices may be associated with catheter related thrombosis. The objective of this study was to determine the risk of catheter related thrombosis associated with the use of an endovascular cooling catheter in patients referred for therapeutic hypothermia following OHCA. METHODS AND RESULTS: We conducted a retrospective cohort study on consecutive patients, referred for therapeutic hypothermia following OHCA, between February 2012 and May 2013. Of 80 patients initially treated with therapeutic hypothermia, 61 completed the cooling protocol using an endovascular cooling device. The primary outcome was catheter related thrombosis defined as evidence of thrombus in the inferior vena cava, deep vein thrombosis or pulmonary embolism during the index hospitalization. We further evaluated the incidence of the primary outcome between patients on dose adjusted intravenous unfractionated heparin compared to those on a subcutaneous prophylactic regimen alone. Catheter related thrombosis was observed in 9/61 (14.7%), with nine events in the prophylaxis group compared to none in the full dose unfractionated heparin group (22.0% vs. 0.0%, p=0.02). CONCLUSIONS: The use of endovascular catheters for induction of therapeutic hypothermia is associated with a high rate of catheter related thrombosis. This risk appears to be abrogated with dose adjusted unfractionated heparin infusion.

A study of heart rate variablity tests and lipid profile in postmenopausal women.

This study was designed to test the hypothesis of alteration of cardiovascular autonomic functions in healthy postmenopausal women and relation of lipid metabolism. Sixty postmenopausal women without any gross systemic disease were selected. The parameters recorded were, Valsalva ratio, heart rate variation with deep breath test, heart rate response to postural change (30:15 R-R interval ratio) and lipid profile. Significant differences in all test results were noticed among the premenopausal and postmenopausal groups. Thirty-seven subjects in postmenopusal group were found to have abnormal autonomic functions while 23 had normal autonomic functions. Results of heart rate variability tests showed significant decrease in values of Valsalva ratio, deep breath test, and 30:15 R-R interval ratio in subjects having abnormal autonomic functions. Results of lipid profile showed significant increase in values of total cholesterol (TC), low density lipoprotein (LDL), triglyceride (TG), cholesterol/ high density lipoprotein (HDL) ratio and insignificant decrease in HDL values in subjects having abnormal autonomic functions. The findings showed that the changes in sex hormone levels, after menopause may alter the autonomic nervous system response and lipid metabolism. It was found that postmenopausal women who had significantly decreased values of heart rate variability tests also had significant increase in values of TC, LDL, TG, cholesterol/HDL ratio and insignificant decrease in values of HDL, suggesting that dyslipidaemia may be an important factor for development of autonomic dysfunction.

Impairment of human cell-based vasculogenesis in rats by hypercholesterolemia-induced endothelial dysfunction and rescue with L-arginine supplementation.

OBJECTIVE: Clinical efficacy of cardiac cell therapy may be compromised by its target population, patients with endothelial dysfunction. In vivo inhibition by endothelial dysfunction has been demonstrated for protein angiogenesis but remains unclear for cell therapy. We examined whether hypercholesterolemia inhibits vasculogenic effects of transplanted human circulating progenitor cells in ischemic tissue and whether L-arginine, a nitric oxide donor, might prevent impairment. METHODS: Athymic rats were fed either normal (group A) or high-cholesterol diets, the latter without (group B) or with (group C) oral L-arginine supplementation. Two weeks later, these rats underwent left femoral artery ligation followed by injection of 2 x 10(6) human circulating progenitor cells into left hind-limb muscle. A fourth group (group D) received supplemented high-cholesterol diets but no cells. RESULTS: Group B had biochemical evidence of endothelial dysfunction and reduced tissue endothelial nitric oxide synthase expression, whereas group A levels were the same as in group C. By 21 postoperative days, left hind-limb perfusion had recovered fully in groups A and C, partially in D, and not at all in B (38% lower than group A, P < or = .004). Lower arteriolar densities were found in groups and B and D than in groups A and C (P < or = .02). Engrafted human cell numbers were equivalent in all cell-transplanted groups after 3 weeks. CONCLUSIONS: Endothelial dysfunction inhibited effects of cell therapy, specifically vasculogenesis, suggesting a role for substrate modification to overcome this inhibition. Involved mechanisms appear related to use of cells but not engraftment and require further investigation.

Genito-urinary fistulae--an evaluation.

A total number of 39 cases of genito-urinary fistulae were managed during the period January, 2001 to August, 2006 in the department of obstetrics and gynaecology, Burdwan Medical College, Burdwan. All patients were evaluated clinically and investigations done accordingly. The incidence of genito-urinary fistula was 0.74% of all gynaecological operations. Out of 39 cases, 23 were primipara, 41.02% were in the age group 20-30 years. In 20 cases the site was at midvaginal region. Prolonged and obstructed labour constituted the major aetiology in 25 cases. Surgery was contemplated in 34 cases. Thirty cases had successful operation after primary surgery, 3 cases had successful repair after second attempt. Only one case needed third attempt. Urethral catheter was required in 15 cases. Proper training of the care providers, more vigilant intrapartum care and timely referral are the important factors to minimise the distressing disorder.

Enterovirus 70 binds to different glycoconjugates containing alpha2,3-linked sialic acid on different cell lines.

Enterovirus 70 (EV70), the causative agent of acute hemorrhagic conjunctivitis, exhibits a restricted tropism for conjunctival and corneal cells in vivo but infects a wide spectrum of mammalian cells in culture. Previously, we demonstrated that human CD55 is a receptor for EV70 on HeLa cells but that EV70 also binds to sialic acid-containing receptors on a variety of other human cell lines. Virus recognition of sialic acid attached to underlying glycans by a particular glycosidic linkage may contribute to host range, tissue tropism, and pathogenesis. Therefore, we tested the possibility that EV70 binds to alpha2,3-linked sialic acid, like other viruses associated with ocular infections. Through the use of linkage-specific sialidases, sialyltransferases, and lectins, we show that EV70 recognizes alpha2,3-linked sialic acid on human corneal epithelial cells and on U-937 cells. Virus attachment to both cell lines is CD55 independent and sensitive to benzyl N-acetyl-alpha-D-galactosaminide, an inhibitor of O-linked glycosylation. Virus binding to corneal cells, but not U-937 cells, is inhibited by proteinase K, but not by phosphatidylinositol-specific phospholipase C treatment. These results are consistent with the idea that a major EV70 receptor on corneal epithelial cells is an O-glycosylated, non-glycosyl phosphatidylinositol-anchored membrane glycoprotein containing alpha2,3-linked sialic acid, while sialylated receptors on U-937 cells are not proteinaceous.