Non-invasive three-dimensional electrical activation mapping to predict cardiac resynchronization therapy response: site of latest left ventricular activation relative to pacing site.

AIMS: Pacing remote from the latest electrically activated site (LEAS) in the left ventricle (LV) may diminish response to cardiac resynchronization therapy (CRT). We tested whether proximity of LV pacing site (LVPS) to LEAS, determined by non-invasive three-dimensional electrical activation mapping [electrocardiographic Imaging (ECGI)], increased likelihood of CRT response. METHODS AND RESULTS: Consecutive CRT patients underwent ECGI and chest/heart computed tomography 6-24 months of post-implant. Latest electrically activated site and the distance to LVPS (dp) were assessed. Left ventricular end-systolic volume (LVESV) reduction of ≥15% at clinical follow-up defined response. Logistic regression probabilistically modelled non-response; variables included demographics, heart failure classification, left bundle branch block (LBBB), ischaemic heart disease (IHD), atrial fibrillation, QRS duration, baseline ejection fraction (EF) and LVESV, comorbidities, use of CRT optimization algorithm, angiotensin-converting enzyme inhibitor(ACE)/angiotensin-receptor blocker (ARB), beta-blocker, diuretics, and dp. Of 111 studied patients [64 ± 11 years, EF 28 ± 6%, implant duration 12 ± 5 months (mean ± SD), 98% had LBBB, 38% IHD], 67% responded at 10 ± 3 months post CRT-implant. Latest electrically activated sites were outside the mid-to-basal lateral segments in 35% of the patients. dp was 42 ± 23 mm [31 ± 14 mm for responders vs. 63 ± 24 mm non-responders (P < 0.001)]. Longer dp and the lack of use of CRT optimization algorithm were the only independent predictors of non-response [area under the curve (AUC) 0.906]. dp of 47 mm delineated responders and non-responders (AUC 0.931). CONCLUSION: The distance between LV pacing site and latest electrical activation is a strong independent predictor for CRT response. Non-invasive electrical evaluation to characterize intrinsic activation and guide LV lead deployment may improve CRT efficacy.

Distribution of varicella-zoster virus (VZV) wild-type genotypes in northern and southern Europe: evidence for high conservation of circulating genotypes.

Phylogenetic analysis of 19 complete VZV genomic sequences resolves wild-type strains into 5 genotypes (E1, E2, J, M1, and M2). Complete sequences for M3 and M4 strains are unavailable, but targeted analyses of representative strains suggest they are stable, circulating VZV genotypes. Sequence analysis of VZV isolates identified both shared and specific markers for every genotype and validated a unified VZV genotyping strategy. Despite high genotype diversity no evidence for intra-genotypic recombination was observed. Five of seven VZV genotypes were reliably discriminated using only four single nucleotide polymorphisms (SNP) present in ORF22, and the E1 and E2 genotypes were resolved using SNP located in ORF21, ORF22 or ORF50. Sequence analysis of 342 clinical varicella and zoster specimens from 18 European countries identified the following distribution of VZV genotypes: E1, 221 (65%); E2, 87 (25%); M1, 20 (6%); M2, 3 (1%); M4, 11 (3%). No M3 or J strains were observed.

Chemical contamination of the Rybinsk Reservoir, northwest Russia: relationship between liver polychlorinated biphenyls (PCB) content and health indicators in bream (Abramis brama).

The Rybinsk Reservoir (Russia) is the largest artificial waterbody in Europe (4550 km2) and provides drinking water for population of the cities located along the coast line. Industrialization in Cherepovets at the northeastern portion of the reservoir, including one of the largest metallurgical facilities in Europe, has resulted in chemical contamination of the reservoir. The extent of polychlorinated biphenyls (PCB) contamination in bream liver, a common fish species, taken from six locations in the Rybinsk Reservoir and Volga River, and biochemical and morphometric biomarkers of fish health were investigated. Liver PCB concentrations ranged from non-detected to 3.4 microg/g wet wt of liver, with the greatest concentrations found in fish taken near the industrialized area in Sheksna Reach of Rybinsk Reservoir. The source of the bream contamination is the PCB pollution of bottom organisms and sediments conditioned with industrialization facilities of Cherepovets. The patterns of the PCB congeners in the livers of bream taken near Cherepovets were similar at all of the stations that were sampled around the reservoir and Volga River. Among the common fish health biomarkers used only liver total ChE activity and liver-somatic index in bream near Cherepovets can reflect environmental pollution. Other morphometric (FCF, Clark's condition factors, and spleen-somatic index) and biochemical (protein content and acetylcholinesterase activity in the brain) biomarkers related with fish health varied among locations, but were not correlated to the concentrations of PCBs in the bream livers.