Acute heart failure due to Q fever endocarditis

We report a case of Q fever endocarditis in a patient who presentedwith a slight pyrexia and acute cardiac failure due to aorticincompetence. The diagnosis was made by detecting high titresof serum IgG and IgA antibody against Coxiella burnetii phaseI antigens and confirmed by demonstrating C. burnetii on theexcised aortic valve using immunofluorescene and electron microscopy.Aortic valve replacement was followed by initially successfulantibiotic treatment for 15 months. Reappearance of Ig A anti-phaseI antibodies 5 months later suggested continued presence ofbacteria, although the patient's condition remained satisfactory.In endemic areas, such as rural southern France, Q fever endocarditisshould be considered when there is evidence of acute heart valvedamage but are few other features of infection.     

Not All Tetramer Binding CD8<Superscript>+</Superscript> T Cells Can Produce Cytokines and Chemokines Involved in the Effector Functions of Virus-Specific CD8<Superscript>+</Superscript> T Lymphocytes in HIV-1 Infected Children

In the pediatric human immunodeficiency virus type-1 (HIV-1) infection, the presence of cytotoxic T lymphocytes (CTL) is associated with a slow progression to AIDS. The secretion of cytokines by CTLs may be critical in the control of viral infection. We used the combination of cell surface and intracellular staining to study the functionality of tetramer binding CD8⁺ T cells recognizing two HIV-1 immunodominant epitopes, in peripheral blood mononuclear cells from HIV-1-infected children. A fraction of tetramer positive CD8⁺ T cells produce cytokines (IFN-, TNF-) or chemokines (CCL4, CCL5) after ex vivo stimulation with the cognate peptide. There was a negative correlation between the plasma viral load and the percentage of CD8⁺ Tetramer Gag⁺ T cells secreting IFN-. This is the first report in the context of pediatric HIV-1 infection showing that only a fraction of HIV-1-specific CD8⁺ T cells have the capacity to produce cytokines and chemokines implicated in their antiviral functions.     

Autoradiographic Analyses of Guinea Pig Airway Tissues Following Inhalation Exposure to 14C-Labeled Methyl Isocyanate

Through the use of radioactively labeled methyl isocyanate (MIC),the deposition, penetration, and clearance of this highly reactivecompound in the airway at the tissue and cellular levels havebeen directly examined. Guinea pigs were exposed to ¹⁴C-MICvapors at concentrations ranging from 0.38 to 15.2 ppm for periodsof 1–6 hr. Solubilization of tissues from these animalsshowed the airway tissues to have the highest level of radioactivity.In the nasal region, ¹⁴C deposition, as monitored by histoautoradiography,was limited to the epithelial layer, was related to dose, andwas dependent on the specific epithelial cell type. The squamousepithelium was minimally labeled on the surface and the labeldid not penetrate the cell layer. However, radioactivity wasdetected throughout the entire nasal respiratory epitheliallayer. The lack of nasal deposition in tracheotomized animalsdemonstrated that the ¹⁴C accumulation at this site was dueto the scrubbing action of the nasal region with no contributionfrom blood recirculation. Cellular localization in the tracheobronchialregion showed epithelial and subepithelial deposition in a dose-dependentmanner with accumulation of the label at the subepithelial region.Radioactivity penetrated to the level of the terminal bronchiolebut was not detected in the alveolar region. The persistenceof airway radioactivity over the 48-hr postexposure period monitoredsuggests the covalent modification of airway macromolecules.Despite its broad specificity and high reactivity, MIC undergoesselective reactions in the airways which are dependent on respiratoryregion and cell type.     

Percutaneous Epicardial Radiofrequency Ablation of Ventricular Arrhythmias After Failure of Endocardial Approach: A 9-Year Experience

Epicardial RF Ablation After Endocardial Approach.   Introduction: Management of recurrent ventricular tachycardia (VT) remains difficult. Neither medical treatments nor conventional endocardial radiofrequency (RF) ablation are efficient to prevent some recurrences. In these cases, a percutaneous pericardial approach may be required.
Methods: Among all the patients referred to our center between 1998 and 2007 for a VT ablation, 276 endocardial and 35 epicardial procedures were performed, the latter in case of failure of the conventional approach. We report in this study the efficacy and the safety of these 35 interventions analyzed retrospectively.
Results: Thirty-five epicardial procedures were attempted in 32 patients. An electric storm was present in 5 of 32 (16%) patients, with other individuals presenting with a recurrent VT despite drug therapy and a previous endocardial ablation. Pericardial space was reached in 28 of 32 patients by a xyphoidian puncture. An immediate success of RF on clinical VT was obtained in 22 of 29 (76%) cases. During a mean follow-up of 384 ± 405 days, only 9 patients (26%) experienced a recurrence of a sustained VT. One patient died from tamponade during the procedure despite surgical drainage. Other complications had no significant consequences.
Conclusion: Percutaneous epicardial puncture is feasible and relatively safe in patients with recurrent VT in whom conventional endocardial RF ablation failed. Epicardial RF ablation offers a high success rate in these challenging patients with only few severe complications. (J Cardiovasc Electrophysiol, Vol. 21, pp. 56–61, January 2010)     

Coronary Thrombo-Aspiration

Persistence of a thrombus after coronary angioplasty can be treated by transcatheter aspiration. This technique has been used in the right coronary artery of three patients. Coronary arteriography showed the occlusion of the proximal segment in two patients and a stenosis in one. In the two patients with an occlusion, there was no residual stenosis after balloon angioplasty, but a long thrombus remained: in the third patient, the thrombosis of the mid-segment of the right coronary artery was secondary to a spasm of the proximal and mid-segments. In all patients, the guiding catheter was gently advanced up to the thrombus that was aspirated with a syringe. The immediate result was excellent, and the control angiogram performed after a delay of 1 to 15 months showed the patency of the artery and the absence of residual stenosis.