Herpes encephalitis in an elderly immunocompetent lady – A case report

Herpes zoster encephalitis is a rare complication of varicella zoster virus infection. As its clinical presentation is usually non-specific, it often goes unrecognized. Advent of polymerase chain reaction test for detecting viral particles in the cerebrospinal fluid has enabled rapid and accurate diagnosis

Early vs. deferred catheter ablation of ventricular tachycardia in patients of ischaemic substrate: systematic review and meta-analysis of clinical outcomes

Aims: Ventricular tachycardia (VT) ablation has been shown to reduce the recurrence of VT episodes, but the timing of performing VT ablation (early; at the time of implantable cardioverter defibrillator implantation) or (deferred: after the patient has received ICD shocks) remains controversial. The objective is to conduct a systematic review and meta-analysis of published data from randomized controlled trials (RCTs) in patients with ischaemic cardiomyopathy (ICM) with the aim of comparing outcome of VT ablation stratified by procedural timing. Methods and results: We conducted a meta-analysis of seven landmark RCTs which included patients with ICM who were either at a high risk of VT or experienced VT/ICD shocks. The primary outcome of VT recurrence was compared according to the timing of performing VT ablation (early vs. deferred). In addition, we also compared the secondary outcome of cardiac mortality. Following a comprehensive search strategy, a total of seven RCTs were included within the final analysis. Based on a pooled analysis, early VT ablation was associated with a significant reduction in the primary outcome [pooled odds ratio (OR) of 0.72, 95% confidence interval (CI): 0.55–0.95, P 30% vs. those with LVEF 30% amongst this ICM cohort

Radiofrequency cardiac ablation with catheters placed on opposing sides of the ventricular wall: Computer modelling comparing bipolar and unipolar modes

Purpose: The aim of this study was to compare the efficacy of bipolar (BM) vs. unipolar (UM) mode of radiofrequency ablation (RFA) in terms of creating transmural lesions across the interventricular septum (IVS) and ventricular free wall (VFW). Materials and methods: We built computational models to study the temperature distributions and lesion dimensions created by BM and UM on IVS and VFW during RFA. Two different UM types were considered: sequential (SeUM) and simultaneous (SiUM). The effect of ventricular wall thickness, catheter misalignment, epicardial fat, and presence of air in the epicardial space were also studied. Results: Regarding IVS ablation, BM created transmural and symmetrical lesions for wall thicknesses up to 15 mm. SeUM and SiUM were not able to create transmural lesions with IVS thicknesses >= 12.5 and 15 mm, respectively. Lesions were asymmetrical only with SeUM. For VFW ablation, BM also created transmural lesions for wall thicknesses up to 15 mm. However, with SeUM and SiUM transmurality was obtained for VFW thicknesses <= 7.5 and 12.5 mm, respectively. With the three modes, VFW lesions were always asymmetrical. In the scenario with air or a fat tissue layer on the epicardial side, only SiUM was capable of creating transmural lesions. Overall, BM was superior to UM in IVS and VFW ablation when the catheters were not aligned. Conclusions: Our findings suggest that BM is more effective than UM in achieving transmurality across both ventricular sites, except in the situation of the epicardial catheter tip surrounded by air or placed over a fat tissue layer.This work received financial support from the Spanish 'Plan Nacional de I+D+I del Ministerio de Ciencia e Innovacion' (TEC2011-27133-C02-01), and from the Universitat Politecnica de Valencia (PAID-06-11 Ref. 1988). A. Gonzalez-Suarez is the recipient of a Grant VaLi+D (ACIF/2011/194) from the Generalitat Valenciana, Spain. 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