scholarly journals Substrate mapping of the left atrium in persistent atrial fibrillation: spatial correlation of localized complex conduction patterns in global charge-density maps to low-voltage areas in 3D contact bipolar voltage maps

2021 ◽  
Author(s):  
Gian-Battista Chierchia ◽  
Juan Sieira ◽  
Annelies Vanderper ◽  
Thiago Guimarães Osorio ◽  
Gezim Bala ◽  
...  
Keyword(s):  
Charge Density ◽  
Left Atrium ◽  
Low Voltage ◽  
Spatial Relationship ◽  
Persistent Atrial Fibrillation ◽  
Bipolar Voltage ◽  
Density Maps ◽  
History Of ◽  
Composite Maps ◽  
The Moment

Abstract Purpose This study aimed to investigate the spatial relationship between low-voltage areas (LVAs) in bipolar voltage mapping (BVM) and localized complex conduction (LCC)-cores in a global, non-contact, charge-density-based imaging, and mapping system (AcM). Methods Patients with history of index PVI for PsAF and scheduled for a repeat ablation procedure for recurrence of the same arrhythmia were enrolled between August 2018 and February 2020. All patients underwent both substrate mappings of the left atrium (LA) with the CARTO 3D map-ping system and with AcM. Results Ten patients where included in our analysis. All presented with persistency of PVI in all veins at the moment of repeat procedure. There was no linear relationship in BVM maps between SR and CSd (correlation coefficient 0.31 ± 0.15), SR and CSp (0.36 ± 0.12) and CSd and CSp (0.43 ± 0.10). The % overlap of localized irregular activation (LIA), localized rotational activation (LRA) and Focal (F) regions with LVA was lower at 0.2 mV compared to 0.5 mV (4.97 ± 7.39%, 3.27 ± 5.25%, 1.09 ± 1.92% and 12.59 ± 11.81%, 7.8 ± 9.20%, 4.62 ± 5.27%). Sensitivity and specificity are not significantly different when comparing composite maps with different LVA cut-offs. AURC was 0.46, 0.48, and 0.39 for LIA, LRA, and Focal, respectively. Conclusion Due to wave front direction dependency, LVAs mapped with BVM in sinus rhythm and during coronary sinus pacing only partially overlap in patients with PsAF. LCC-cores mapped during PsAF partially co-localize with LVAs.

scholarly journals The Prevalence of Low Voltage in Left Atrium in Persistent Atrial Fibrillation: Examination in Cases Maintaining Sinus Rhythm after Pharmacologic Defibrillation

2011 ◽  
Vol 27 (Supplement) ◽  
pp. PE4_040
Author(s):  
Higashi Yukei ◽  
Hisa Shimojima ◽  
Daisuke Wakatsuki ◽  
Sayaka Yamaya ◽  
Tokutada Sato ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Sinus Rhythm ◽  
Left Atrium ◽  
Low Voltage ◽  
Persistent Atrial Fibrillation

A novel multielectrode catheter for high-density ventricular mapping: electrogram characterization and utility for scar mapping

EP Europace ◽  
2020 ◽  
Author(s):  
Michael Barkagan ◽  
Jakub Sroubek ◽  
Ayelet Shapira-Daniels ◽  
Hagai Yavin ◽  
Jihye Jang ◽  
...  
Keyword(s):  
Surface Area ◽  
Low Voltage ◽  
Near Field ◽  
Gadolinium Enhancement ◽  
Acquisition Rate ◽  
Bipolar Voltage ◽  
Density Maps ◽  
Ventricular Tachycardias ◽  
Low Amplitude ◽  
Mapping Catheter

Abstract Aims Multielectrode mapping catheters can be advantageous for identifying surviving myocardial bundles in scar. This study aimed to evaluate the utility of a new multielectrode catheter with increased number of small and closely spaced electrodes for mapping ventricles with healed infarction. Methods and results In 12 swine (four healthy and eight with infarction), the left ventricle was mapped with investigational (OctarayTM) and standard (PentarayTM) multielectrode mapping catheters. The investigational catheter has more electrodes (48 vs. 20), each with a smaller surface area (0.9 vs. 2.0 mm2) and spacing is fixed at 2 mm (vs. 2–6–2 mm). Electrogram (EGM) characteristics, mapping efficiency and scar description were compared between the catheters and late gadolinium enhancement (LGE). Electrogram acquisition rate was faster with the investigational catheter (814 ± 126 vs. 148 ± 58 EGM/min, P = 0.02) resulting in higher density maps (38 ± 10.3 vs. 10.1 ± 10.4 EGM/cm2, P = 0.02). Bipolar voltage amplitude was similar between the catheters in normal and infarcted myocardium (P = 0.265 and P = 0.44) and the infarct surface area was similar between the catheters (P = 0.12) and corresponded to subendocardial LGE. The investigational catheter identified a higher proportion of near-field local abnormal ventricular activities within the low-voltage area (53 ± 16% vs. 34 ± 16%, P = 0.03) that were considered far-field EGMs by the standard catheter. The investigational catheter was also advantageous for mapping haemodymically non-tolerated ventricular tachycardias due to its higher acquisition rate (P < 0.001). Conclusion A novel multielectrode mapping catheter with higher number of small, and closely spaced electrodes increases the mapping speed, EGM density and the ability to recognize low amplitude near-field EGMs in ventricles with healed infarction.

Spatial Relationship of Focal Impulses, Rotors and Low Voltage Zones in Patients With Persistent Atrial Fibrillation

2016 ◽  
Vol 27 (5) ◽  
pp. 507-514 ◽  
Author(s):  
ANJA SCHADE ◽  
KARIN NENTWICH ◽  
LISA C. COSTELLO-BOERRIGTER ◽  
PHILIPP HALBFASS ◽  
PATRICK MUELLER ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Low Voltage ◽  
Spatial Relationship ◽  
Persistent Atrial Fibrillation ◽  
Relationship Of

Evaluation of concomitant gynecological pathology in group of patients of reproductive age with tumors and tumor formations

2020 ◽  
pp. 10-14
Author(s):  
N. V. Spiridonova ◽  
A. A. Demura ◽  
V. Yu. Schukin
Keyword(s):  
Diagnostic Errors ◽  
Ovarian Tumors ◽  
Reproductive Age ◽  
Women Of Reproductive Age ◽  
Predisposing Factor ◽  
Ovarian Tumours ◽  
Preoperative Diagnostic ◽  
Neoplastic Process ◽  
History Of ◽  
The Moment

According to modern literature, the frequency of preoperative diagnostic errors for tumour-like formations is 30.9–45.6%, for malignant ovarian tumors is 25.0–51.0%. The complexity of this situation is asymptomatic tumor in the ovaries and failure to identify a neoplastic process, which is especially important for young women, as well as ease the transition of tumors from one category to another (evolution of the tumor) and the source of the aggressive behavior of the tumor. The purpose of our study was to evaluate the history of concomitant gynecological pathology in a group of patients of reproductive age with ovarian tumors and tumoroid formations, as a predisposing factor for the development of neoplastic process in the ovaries. In our work, we collected and processed complaints and data of obstetric and gynecological anamnesis of 168 patients of reproductive age (18–40 years), operated on the basis of the Department of oncogynecology for tumors and ovarian tumours in the Samara Regional Clinical Oncology Dispensary from 2012 to 2015. We can conclude that since the prognosis of neoplastic process in the ovaries is generally good with timely detection and this disease occurs mainly in women of reproductive age, doctors need to know that when assessing the parity and the presence of gynecological pathology at the moment or in anamnesis, it is not possible to identify alarming risk factors for the development of cancer in the ovaries.

The Goal of the Moment (Summary of the Lecture Delivered by Ivan Ilyin in May 1917)

2019 ◽  
Vol 60 ◽  
pp. 424-428
Author(s):  
Alexandra I. Vakulinskaya
Keyword(s):  
The State ◽  
October Revolution ◽  
Legal Consciousness ◽  
New Order ◽  
History Of ◽  
The Moment

This publication is devoted to one of the episodes of I. A. Ilyin’s activity in the period “between two revolutions”. Before the October revolution, the young philosopher was inspired by the events of February 1917 and devoted a lot of time to speeches and publications on the possibility of building a new order in the state. The published archive text indicates that the development of Ilyin’s doctrine “on legal consciousness” falls precisely at this tragic moment in the history of Russia.

scholarly journals Relationship between left atrial strain and left atrial bipolar voltage in patients undergoing catheter ablation for atrial fibrillation

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
Y Takahashi ◽  
T Kitai ◽  
T Watanabe ◽  
T Fujita
Keyword(s):  
Atrial Fibrillation ◽  
Left Atrial ◽  
Speckle Tracking ◽  
Longitudinal Strain ◽  
Low Voltage ◽  
Pulmonary Veins ◽  
Global Longitudinal Strain ◽  
Inferior Wall ◽  
Bipolar Voltage ◽  
Global Mean

Abstract Background Low-voltage zone (LVZ) in the left atrium (LA) seems to represent fibrosis. LA longitudinal strain assessed by speckle tracking method is known to correlate with the extent of fibrosis in patients with mitral valve disease. Purpose We sought to identify the relationship between LA longitudinal strain and LA bipolar voltage in patients with atrial fibrillation (AF). We tested the hypothesis that LA strain can predict LA bipolar voltage. Methods A total of 96 consecutive patients undergoing initial AF ablation were analyzed. All patients underwent transthoracic echocardiography including 2D speckle tracking measurement on the day before ablation during sinus rhythm (SR group, N=54) or during AF (AF group, N=42). LA longitudinal strain was measured at basal, mid, and roof level of septal, lateral, anterior, and inferior wall in apical 4- and 2-chamber view. Global longitudinal strain (GLS) was defined as an average value of the 12 segments. LA voltage map was created using EnSite system, and global mean voltage was defined as a mean of bipolar voltage of the whole LA excluding pulmonary veins and left atrial appendage. LVZ was defined as less than 1.0 mV. Results There was a significantly positive correlation between GLS and global mean voltage (r=0.708, p<0.001). Multivariate regression analysis showed that GLS and age were independent predictors of global mean voltage. There was a significant negative correlation between global mean voltage and LVZ areas. Conclusions There was a strong correlation between LA longitudinal strain and LA mean voltage. GLS can independently predict LA mean voltage, subsequently LVZ areas in patients with AF. Funding Acknowledgement Type of funding source: None

scholarly journals Decolonization and the aesthetics of disorder: Naipaul, Evaristo, Boland

2021 ◽  
pp. 002198942199605
Author(s):  
Matthew Whittle
Keyword(s):  
European History ◽  
Resistance Movements ◽  
Eavan Boland ◽  
History Of ◽  
Paul Gilroy ◽  
Orderly Transition ◽  
The Moment ◽  
Bear Witness ◽  
Formal Features

Decolonization is presented in dominant accounts as an orderly transition and not the culmination of anticolonial resistance movements. This in turn contributes to what Paul Gilroy terms an endemic “post-imperial melancholia” across contemporary European nations and the removal of empire and its demise from understandings of European history. Drawing on Bill Schwarz’s reconceptualization of a Fanonian commitment to disorder, this article focuses on Britain’s history of colonialism and post-imperial immigration and argues for the mapping of a disorderly aesthetics in works by V. S. Naipaul, Bernardine Evaristo, and Eavan Boland. The three formal features of non-linearity, polyvocality, and environmental imagery enable these writers to bear witness to the complex histories of empire, transatlantic slavery, decolonization, and immigration from the colonial “margins”. These “aesthetics of disorder” counter a dominant narrative of decolonial order and challenge conceptions of British exceptionalism that were reinforced at the moment of imperial decline.

scholarly journals Presence of low voltage area predicts atrial tachyarrhythmia inducibility with atrial burst pacing after pulmonary vein isolation

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
S Kawai ◽  
K Nagaoka ◽  
S Takase ◽  
K Sakamoto ◽  
H Ikuta ◽  
...  
Keyword(s):  
Pulmonary Vein ◽  
Pulmonary Vein Isolation ◽  
Left Atrial ◽  
Low Voltage ◽  
Past History ◽  
Univariate Analysis ◽  
Atrial Tachyarrhythmia ◽  
Chads2 Score ◽  
Atrial Capture ◽  
History Of

Abstract Background Induction of atrial fibrillation (AF)/atrial tachycardia (AT) by atrial burst pacing following ablation procedure may reflect the presence of residual substrates in the atria that maintain AF. However, the relation between the inducibility and left atrial low voltage area (LVA) has not been established. Methods Fifty-nine patients (65 years old, 43 males) with persistent AF who underwent pulmonary vein isolation (PVI)-based ablation were studied. All patients underwent left atrial voltage mapping during sinus rhythm and atrial burst pacing after PVI. Atrial burst pacing was performed with 30-beat at an amplitude of 10V from the ostium of the coronary sinus; increasing from 240 to 320 ppm in steps of 20 ppm or failure to 1:1 atrial capture. Inducibility was defined as AF/AT lasting more than 5 minutes following burst pacing. Left atrial LVA and other co-variates were analyzed with regard to burst pacing positivity. Results AF/AT was induced by burst pacing in 23 patients (39%). Univariate analysis revealed that past history of stroke, CHADS2 score and presence of left atrial LVA were significantly associated with the inducibility of AF/AT. Multivariate analysis revealed that only the presence of LVA was associated with the inducibility (OR 1.5: per 10% increase; p=0.04). We focused on the relationship between the extent of LVA and burst positivity. AF/AT inducibility increased as low voltage area increased, and it was as high as 72.7% when low voltage area was more than 20% (P<0.05). Interestingly, induced arrhythmia type was AT rather than AF when low voltage area was more than 20%. Conclusions Presence of left atrial LVA is an independent predictor of atrial tachyarrhythmia inducibility after PVI in patients with persistent AF. A large amount of low voltage area is related to AT inducibility rather than AF. Extent of LVA and burst positivity Funding Acknowledgement Type of funding source: None

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