Multipolar endocardial mapping of the right atrium during cardiac catheterization: description of a new technique

AbstractObjectives. Using a new mapping system that allows the simultaneous acquisition of date from 25 right atrial bipolar electrodes during cardiac catheterization, we mapped normal sinus rhythm and atrial reentrant tachycardia in 24 sheep (20 to 49 kg) and 7 pigs (25 to 35 kg).Background. Rapid, high resolution mapping during cardiac catheterization may shorten ablation procedures and permit ablation of otherwise refractory arrhythmias.Methods. A flexible, elliptic, basket-shaped recording catheter has five spokes, each with 10 electrodes arranged as 5 bipolar pairs. Catheter shape, electrode spacing and introduction technique were modified in response to the results of experiments in the first 23 animals. In the most recent eight animals, retraction of a string attached to the distal tip distended the basket, providing safe tissue contact. Filtered (30 to 250 Hz) bipolar recordings from all 25 electrode pairs, as well as a surface electrocardiogram, were recorded and digitized at 1,000 Hz using custom software. An activation map was digitally constructed and superimposed on anteroposterior and lateral fluoroscopic catheter images. Bipolar recordings were made in normal sinus rhythm (31 animals), with adequate signals recorded from >95% of electrode pairs. Rapid burst pacing and intentional right atrial air embolus (30 to 50 ml) induced sustained atrial reentrant tachycardia in five animais, which was also adequately recorded.Results. Catheter positioning and complete atrial mapping required <10 min after venous access in the most recent eight experiments. The catheter was left in position for up to 4 h. Postmortem evaluation revealed minor superficial abrasion of the venae cavae or right atrial endocardium in six animals and moderate abrasion in two. No other damage was observed.Conclusions. This new system may ultimately assist in mapping simple or complex atrial arrhythmias during cardiac eatheterization

Multi-Omics of Tomato Glandular Trichomes Reveals Distinct Features of Central Carbon Metabolism Supporting High Productivity of Specialized Metabolites

Glandular trichomes are metabolic cell factories with the capacity to produce large quantities of secondary metabolites. Little is known about the connection between central carbon metabolism and metabolic productivity for secondary metabolites in glandular trichomes. To address this gap in our knowledge, we performed comparative metabolomics, transcriptomics, proteomics, and (13)C-labeling of type VI glandular trichomes and leaves from a cultivated (Solanum lycopersicum LA4024) and a wild (Solanum habrochaites LA1777) tomato accession. Specific features of glandular trichomes that drive the formation of secondary metabolites could be identified. Tomato type VI trichomes are photosynthetic but acquire their carbon essentially from leaf sucrose. The energy and reducing power from photosynthesis are used to support the biosynthesis of secondary metabolites, while the comparatively reduced Calvin-Benson-Bassham cycle activity may be involved in recycling metabolic CO2 Glandular trichomes cope with oxidative stress by producing high levels of polyunsaturated fatty acids, oxylipins, and glutathione. Finally, distinct mechanisms are present in glandular trichomes to increase the supply of precursors for the isoprenoid pathways. Particularly, the citrate-malate shuttle supplies cytosolic acetyl-CoA and plastidic glycolysis and malic enzyme support the formation of plastidic pyruvate. A model is proposed on how glandular trichomes achieve high metabolic productivity

Current Role of Cardiac and Extra-Cardiac Pathologies in Clinically Indicated Cardiac Computed Tomography with Emphasis on Status Before Pulmonary Vein Isolation

Purpose: The aim of this study was to assess the incidence of cardiac and significant extra-cardiac findings in clinical computed tomography of the heart in patients with atrial fibrillation before pulmonary vein isolation (PVI). Materials and Methods: 224 patients (64 +/- 10 years; male 63 %) with atrial fibrillation were examined by cardiac 64-slice multidetector CT before PVI. Extra-cardiac findings were classified as significant if they were recommended to additional diagnostics or therapy, and otherwise as non-significant. Additionally, cardiac findings were documented in detail. Results: A total of 724 cardiac findings were identified in 203 patients (91 % of patients). Additionally, a total of 619 extra-cardiac findings were identified in 179 patients (80 % of patients). Among these extra-cardiac findings 196 (32 %) were significant, and 423 (68 %) were non-significant. In 2 patients (1 %) a previously unknown malignancy was detected (esophageal cancer and lung cancer, local stage, no metastasis). 203 additional imaging diagnostics followed to clarify the significant findings (124 additional CT, costs 38 314.69 US dollars). Overall, there were 3.2 cardiac and 2.8 extra-cardiac findings per patient. Extra-cardiac findings appear significantly more frequently in patients over 60 years old, in smokers and in patients with a history of cardiac findings (p < 0.05). Conclusion: Cardiac CT scans before PVI should be screened for extracardiac incidental findings that could have important clinical implications for each patient. Key points: Cardiac and extra-cardiac findings are common in patients with an indication for pulmonary vein isolation on previous CT scans. Malignancies can be detected in 1 % of all patients. 32 % of all extra-cardiac findings can be of significant relevance with consequences for patients. Altogether, there are 3.2 cardiac and 2.8 extra-cardiac findings in patients with indication for pulmonary vein isolation and CT. Extra-cardiac findings appear significantly more frequently in patients over 60 years old, in smokers and in patients with a history of cardiac findings (p < 0.05). Citation Format:. Sohns JM, Menke J, Staab W et al. Current Role of Cardiac and Extra-Cardiac Pathologies in Clinically Indicated Cardiac Computed Tomographywith Emphasis on Status Before Pulmonary Vein Isolation