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The relationship between endogenous oleic acid produced by hepatic delta9-desaturase and the secretion of VLDL-triglycerides was investigated in a primary culture of chicken hepatocytes. When the fatty acid compositions of the secreted and intracellular triglycerides (TG) (or triacylglycerols) were compared, an imbalance between monoenes and saturated fatty acids was observed, with the secreted TG being significantly more unsaturated than the intracellular TG. The addition of a mixture of cyclopropenic fatty acids (specific inhibitors of fatty acid desaturation) to the culture medium of cells 24 h before measurement of their delta9-desaturase activity and TG secretion rate caused a significant impairment of both desaturase activity and TG secretion, without affecting total TG synthesis. However, the addition of oleic acid to the culture medium of cells treated with cyclopropenic fatty acids restored the TG secretion rate. Palmitic acid did not restore the TG secretion rate and linoleic acid partly restored the TG secretion rate. Finally, even in the presence of oleic acid in the culture medium of secreting cells, those which had been treated with cyclopropenic fatty acids had a significantly lower TG secretion rate than nontreated cells. Taken together, these results show that TG secretion is highly dependent on the delta9-desaturase activity and suggest that oversecretion of VLDL-TG in chickens and subsequent fattening could originate in a high hepatic delta9-desaturation of saturated fatty acids. [ABSTRACT FROM AUTHOR]

Background: A pacemaker implantation is not indicated in cases of reversible high-degree symptomatic sinus node dysfunction (SND) and atrioventricular block (AVB). However, it remains uncertain whether these reversible automaticity/conduction disorders may recur in some patients at follow-up, in the absence of reversible cause. This retrospective study aimed to determine the incidence and predictive factors of permanent pacemaker (PPM) implantation at follow-up and after reversible high-degree SND/AVB., Methods: Based on medical electronic files codes, we identified patients who were hospitalized in our cardiac intensive care unit between January 2003 and December 2020 due to reversible high-degree SND/AVB and who were discharged from the hospital alive and without PPM implantation. Acute myocardial infarction and post-cardiac surgery patients were excluded. We categorized the patients according to the need for PPM at follow-up due to non-reversible high-degree SND/AVB., Results: Of the 93 patients included, 26 patients (28%) were readmitted for PPM implantation at follow-up after hospital discharge. Among baseline characteristics, compared with patients who did not have high-degree SND/AVB recurrence, those who had subsequent PPM implantation had less frequent previous hypertension (70% vs. 46%, p = .031). Regarding the initial causes of reversible SND/AVB, isolated hyperkalemia was found more often in the patients readmitted for PPM (19% vs. 3% vs. p = .017). Moreover, recurrence of high-degree SND/AVB was significantly associated with the presence of intraventricular conduction disorders (either bundle branch block or left bundle branch hemiblock) on ECG at discharge (36% in patients without PPM vs. 68% in PPM patients, p = .012)., Conclusion: Almost one third of the patients discharged alive from the hospital after a reversible high-degree SND/AVB needed a pacemaker implantation at follow-up. Complete bundle branch block or left bundle branch hemiblock on discharge ECG after recovery of atrioventricular conduction and/or sinus automaticity was associated with a greater risk of recurrence leading to pacemaker implantation., (© 2023 The Authors. Pacing and Clinical Electrophysiology published by Wiley Periodicals LLC.)

Background: There is a paucity of randomized data regarding the safety and efficacy of the use of intracardiac echocardiography (ICE) from the left atrium (LA) to guide left atrial appendage occlusion (LAAO) procedures under local anesthesia using either of the available devices., Hypothesis: The aim of this study was to compare the efficacy and safety of ICE from the LA with transesophageal echocardiography (TEE) for guidance during transcatheter LAAO procedures., Methods: Single-center, cohort study of patients undergoing LAAO with the Amplatzer Cardiac Plug or Watchman device. Procedures were guided by ICE from the LA with local anesthesia (n = 175) or TEE under general anesthesia (n = 49). Efficacy outcomes were procedural success and peri-device leaks 6 weeks after LAAO. The safety outcome was a composite of procedure-related complications., Results: Procedural success was similar between groups: 100% in the TEE-guided group, and 98% in the ICE-guided group. Procedure-related complications such as death, embolism, migration, or major vascular complications occurred similarly between groups (p = 0.590). The rate and degree of peri-device leaks or presence of a thrombus on the device did not differ between groups on follow-up CT. Turnover time in the catheter laboratory and use of contrast agent were reduced with ICE., Conclusions: ICE in the left atrium to guide LAAO procedures appears to be as effective and safe as TEE. There was no increase in procedure-related complications, whatever the device used. ICE resulted in similar procedural success while decreasing procedure time and requiring only local anesthesia., (© 2021 The Authors. Clinical Cardiology published by Wiley Periodicals LLC.)

Background: Atrial fibrillation (AF) is common after acute myocardial infarction (AMI) and associated with in-hospital and long-term mortality. However, the pathophysiology of AF in AMI is poorly understood. Heart rate variability (HRV), measured by Holter-ECG, reflects cardiovascular response to the autonomic nervous system and altered (reduced or enhanced) HRV may have a major role in the onset of AF in AMI patients. Objective: We investigated the relationship between autonomic dysregulation and new-onset AF during AMI. Methods: As part of the RICO survey, all consecutive patients hospitalized for AMI at Dijon (France) university hospital between June 2001 and November 2014 were analyzed by Holter-ECG <24 h following admission. HRV was measured using temporal and spectral analysis. Results: Among the 2040 included patients, 168 (8.2%) developed AF during AMI. Compared to the sinus-rhythm (SR) group, AF patients were older, had more frequent hypertension and lower left ventricular ejection fraction LVEF. On the Holter parameters, AF patients had higher pNN50 values (11% vs. 4%, p < 0.001) and median LH/HF ratio, a reflection of sympathovagal balance, was significantly lower in the AF group (0.88 vs 2.75 p < 0.001). The optimal LF/HF cut-off for AF prediction was 1.735. In multivariate analyses, low LF/HF <1.735 (OR(95%CI) = 3.377 (2.047-5.572))was strongly associated with AF, ahead of age (OR(95%CI) = 1.04(1.01-1.06)), mean sinus-rhythm rate (OR(95%CI) = 1.03(1.02-1.05)) and log NT-proBNP (OR(95%CI) = 1.38(1.01-1.90). Conclusion: Our study strongly suggests that new-onset AF in AMI mainly occurs in a dysregulated autonomic nervous system, as suggested by low LF/HF, and higher PNN50 and RMSSD values., Competing Interests: The authors declare no conflict of interest.

Silent atrial fibrillation (AF) is an asymptomatic atrial arrhythmia that can be diagnosed by chance during a systematic electrocardiogram, an external Holter, or from implanted cardiac devices. There is a significant body of the literature around silent AF, yet it remains largely underdiagnosed in everyday clinical practice. Meanwhile, new diagnostic tools have significantly improved the detection of silent AF, creating a potential for mass screening via new technologies and the promise of a major step forward in e-health progress. However, it is not yet known whether silent AF is associated with the same thromboembolic risk as symptomatic AF, and whether these asymptomatic and often short-lasting episodes therefore require anticoagulation therapy and rhythm management.

In 2030, the European Union will include 14 to 17 million atrial fibrillation (AF) patients, with 120,000 to 215,000 new cases each year. The increase in the prevalence of this arrhythmia has led to the development of new therapeutic intervention strategies to manage the different aspects of this disease. Thus, endocavitary or epicardial ablation of AF, by radiofrequency or cryoablation, provides superior results to antiarrhythmic therapy in controlling symptoms and preventing heart failure in paroxysmal or persistent AF. In heart failure patients with advanced AF, the ablation of the atrioventricular junction associated with the implantation of a bi-ventricular pacemaker has just demonstrated its clear superiority, bringing this technique up to date. Finally, in the event of a major bleeding risk and contraindication to anticoagulants, percutaneous occlusion of the left atrium has proven its value in preventing AF-related embolic events. The future will certainly see the emergence of new technologies but also personalized strategies based on an optimal selection of the right candidates for these interventions, thanks in particular to the contribution of imaging before the procedure., (Copyright © 2019 Société Nationale Française de Médecine Interne (SNFMI). Published by Elsevier Masson SAS. All rights reserved.)

New onset atrial fibrillation post-transcatheter aortic valve implantation (TAVI) is common and is associated with adverse outcomes. However, silent atrial fibrillation (AF) is poorly documented in the context. This study sought to evaluate the incidence, predictive factors, and prognostic value of Silent AF post-TAVI. All the consecutive patients with TAVI were prospectively analyzed by continuous electrocardiogram monitoring≥48 hours after implantation. Silent AF was defined as asymptomatic episodes lasting at least 30 seconds. The population was divided into 3 groups: history of AF, no-AF, and silent AF. Among the 206 patients implanted with TAVI, 19 (16.1%) developed silent AF. Compared with the no-AF group, patients with silent AF shared the same clinical characteristics and cardiovascular risk factors. Procedural success and echography parameters after the device implantation were similar between groups. Left atrial volume was significantly increased (p <0.001) in the silent AF group, together with preimplantation C-reactive protein (CRP) >3 mg/L and glucose (p = 0.048 and p = 0.002). By multivariate analysis, CRP >3 mg/dl and logistic European System for Cardiac Operative Risk Evaluation were identified as independent predictors of silent AF. In-hospital and 1-year mortalities were higher in pre-existing AF patients, whereas no-AF and the silent AF patients share the same prognosis. Our prospective study showed for the first time that silent AF is frequent after TAVI procedures. In conclusion, our work suggests that CRP could help to predict the risk of developing silent AF. However, the onset of silent AF is not associated with worse prognosis in the year following the procedure in our study., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Each year, 5 million new cases of atrial fibrillation (AF) are diagnosed, and the data for the last 20 years show that its incidence has continued to grow. The aging of the population is considered a major explanation for this pandemic phenomenon. The complications associated with atrial arrhythmia are numerous and frequent, with in the first place thromboembolic events. In addition to symptomatic atrial fibrillation, AF may be diagnosed by chance during a systematic ECG, an external Holter or a continuous ECG monitor, or in the memories of implanted cardiac devices. This is called silent AF. Despite numerous studies, silent AF is still largely under-diagnosed and unrecognized in everyday clinical practice, although it is a frequent condition with potentially serious consequences (especially thromboembolic events). Thanks to the development of new diagnostic tools, which are scientifically validated and readily available, the detection of AF has improved significantly, leading to better therapeutic management, in particular anticoagulant therapy. From this perspective, mass screening for silent AF using these new technologies is a major step forward in e-health development. The cost of screening and the heterogeneity of populations affected by silent AF, however, remain major obstacles., (Copyright © 2017 Société Nationale Française de Médecine Interne (SNFMI). Published by Elsevier Masson SAS. All rights reserved.)

Background: Acute myocarditis (AM) often involves the left ventricular (LV) subepicardium that might be displayed by cardiac magnetic resonance even late after the acute phase. In the absence of global or regional LV dysfunction, conventional transthoracic echocardiography (TTE) does not accurately identify tissue sequelae of AM. We sought to evaluate the diagnostic value of two-dimensional (2D) and three-dimensional (3D) speckle-tracking echocardiography to identify patients with a history of AM with preserved LV ejection fraction (LVEF)., Methods: Fifty patients (group 1: age, 31.4 ± 10.5 years; 76% males) with a history of cardiac magnetic resonance-confirmed diagnosis of AM (according to the Lake Louise criteria) were retrospectively identified and then (21.7 ± 23.4 months later) evaluated by complete echocardiography including 2D and 3D speckle-tracking analysis, as well as 50 age- and gender-matched healthy controls (group 2: age, 31.2 ± 9.5 years: 76% males). Patients with a history of severe clinical presentation of AM (sudden death, ventricular arrhythmia, heart failure, alteration of LVEF) were excluded., Results: At diagnosis, peak troponin and C-reactive protein were 11.97 (interquartile range, 4.52-25.92) μg/L and 32.3 (interquartile range, 14.85-70.45) mg/L, respectively. Mean delay between acute phase and follow-up study TTE was 21.7 ± 23.4 months. LVEF was not statistically different between groups (62.1% vs 63.5%, P = .099). Two-dimensional global longitudinal strain (GLS) was lower in magnitude in group 1 (-17.8% vs -22.1%, P < .0001) as were 2D layer-specific subepicardial GLS (-15.4% vs -19.7%, P < .0001) and subendocardial GLS (-20.71% vs -25.08%, P < .0001). Three-dimensional global longitudinal, circumferential, area, and radial strains were lower in magnitude in group 1 (-11.80% vs -14.98%, P < .0001; -12.57% vs -15.12%, P < .0001; -22.28% vs -25.87%, P < .0001; 31.47% vs 38.06%, P < .0001, respectively). Receiver operating characteristic curve analysis showed that subepicardial GLS displayed a better diagnostic performance to detect sequelae of AM as compared with GLS (area under the curve = 0.97 vs 0.93, P = .045)., Conclusions: In patients with a history of AM, a subtle LV dysfunction can be detected by 2D and 3D speckle-tracking echocardiography, even though LVEF is conserved, adding incremental information over conventional TTE., (Copyright © 2017 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.)

Main Objective: To better understand the role of myeloperoxidases (MPO) in microvascular obstruction (MO) phenomenon and infarct size (IS) using cardiac magnetic resonance (CMR) data in patients with acute myocardial infarction (AMI)., Method: 40 consecutive patients classified according to the median level of MPO in the culprit artery. A CMR study was performed during the week following AMI and at 6 months, with late gadolinium enhancement sequences., Results: Persistent MO was observed in the same proportion (50 vs. 65%, p = 0.728) between the low vs. high MPO group levels. However, the extent of the microvascular obstruction was significantly greater in the high-MPO group (6 (0-9) vs.16.5 (0-31), p = 0.027), together with a greater infarct size, and a trend towards a lower left ventricular ejection fraction (LVEF) (p = 0.054) at one week. CMR data at 6 months showed that reverse systolic remodeling was two fold more present in the low-MPO group (p = 0.058). Interestingly, the extent of MO (8.5 (6.5-31) vs. 4.1 (3-11.55), p = 0.042) and IS remained significantly greater (24.5 (9.75-35) vs. 7.5 (2.5-18.75), p = 0.022) in the high-MPO group. Moreover, MPO in the culprit artery appeared to correlate positively with MPO in non-culprit arteries and serum, and with troponin levels and peak CK., Conclusion: This patient-based study revealed in patients after AMI that high MPO levels in the culprit artery were associated with more severe microvascular obstruction and greater IS. These findings may provide new insights pathophysiology explanation for the adverse prognostic impact of MO.

A 75-year-old woman was referred for advice regarding surface electrocardiographic modifications after the initiation of rivastigmine. In our patient, the baseline ECGs appeared perfectly normal. However, the initiation of a cholinesterase inhibitor unmasked a left lateral accessory pathway that had never been diagnosed before. Although cholinesterase inhibitors are known to increase vagal tone, the PR interval was shortened after rivastigmine administration, thus excluding this hypothesis to explain the appearance of the accessory pathway. Therefore, we hypothesized that cholinesterase inhibitors may have increased conduction velocity in the accessory pathway or in the atria., (Copyright © 2017 Elsevier Inc. All rights reserved.)