Very (70W) vs. LSI guided (5-6) high power short duration ablation in patients with paroxysmal atrial fibrillation undergoing pulmonary vein vs. pulmonary vein and posterior wall isolation

Funding Acknowledgements

Type of funding sources: None.

Background

high power short duration (HPSD) ablation is at least as safe while reducing procedure time than radiofrequency (RF) ablation with lower power in pts undergoing pulmonary vein isolation (PVI) for paroxysmal atrial fibrillation (AF). Purpose: to compare safety and efficacy of 2 different: 1) RF energy set up (FlexAbility: 70W, 41°, 6-10s, 11ml/h vs. TactiCath: 50W, 41°, LSI 5-6, 17ml/h, both Abbott), and 2) ablation strategies (posterior wall isolation (PWI) in addition to PVI vs. PVI) in pts undergoing their first ablation for paroxysmal AF. Methods: since June 2020 pts are prospectively assigned to alternatively undergo their RF catheter ablation with the FlexAbility (v-HPSD) or the TactiCath (LSI-HPSD) catheters (aim 200 pts). In addition, pts were alternatively assigned to PVI + PWI vs. PVI. All procedures were done using a 3D-mapping system (Ensite Precision), the ablation catheter was stabilized with a long sheath (Agilis) and a continuous series of lesions (4mm) were plotted around the PV, at the roof and between the 2 inferior PVs. On the PW, RF lesions were limited to 6s and 5 LSI for the v-HPSD and LSI-HPSD groups. Endoscopy was performed shortly after ablation in all pts and thermal esophageal lesion (TEL) characterized with the Kansas classification. Results: since June 2020 56 pts [61 ± 13 years old, 17 (30%) female, CHA2DS2-Vasc 2.3 ± 1.5, 55 ± 77 left ventricular ejection fraction] underwent v-HPSD (#28) and LSI-HPSD (#28) ablation. In 2/14 (14%) and in 3/15 (20%) pts (v-HPSD and LSI-HPSD groups, respectively) initially assigned to undergo simple PVI, PWI was added due to PW dependent flutter or evidence of pro-arrhythmic slow conduction on the PW. A shorter RF time to achieve PVI (17 ± 3 vs. 25 ± 6 min; P<.0001) was found for the v-HPSD group, although acute reconnection were numerically higher (9 vs. 4) and procedural time did not differ (32 ± 8 vs. 35 ± 9 min). Whenever attempted, PWI (#16 for each v-HPSD and LSI-HPSD group) was always successful. When v-HPSD and LSI-HPSD group were compared, no differences were found in RF and procedure time both at the roof (2.3 ± 0.9 vs. 2.7 ± 1.1 min and 3 ± 1.4 vs. 3.4 ± 1 min, respectively) and between the 2 inferior PVs (2.6 ± 0.6 vs. 2.9 ± 0.7 min and 4.3 ± 1.9 vs. 3.8 ± 1.2 min, respectively). Total RF (19.7 ± 4.5 vs. 28.5 ± 6.6 min, P<.0001) was shorted in the v-HPSD, but X-Ray (1.4 ± 0.7 vs. 1.2 ± 0.8 min) and total procedural time (102 ± 17 vs. 110 ± 20 min) did not differ. Rate of TELs was not different and found in 18% (#5: 4 I, 1 IIA) and 14% (all IIA) pts assigned to v-HPSD and LSI-HPSD respectively. A numerically higher number of TELs (6 vs. 3) was seen when PWI was pursued, although this did not prolong total RF and procedure time. Conclusion: a shorter RF time is associated with v-HPSD vs. LSI-HPSD strategy, although procedural time did not differ. TELs are a relative rare finding, and only numerically higher when isolation of the PW is pursued in addition to PV isolation.

1249Acute efficacy and safety of pulmonary vein isolation for atrial fibrillation in patients alternatively assigned to high power short duration (70W, 8s) vs lesion index guided (35W) ablation

Background

permanent trans-mural lesions not affecting surrounding anatomical structures is the goal of safe and effective wide antral pulmonary vein (PV) isolation in patients with paroxysmal and persistent atrial fibrillation (AF) undergoing catheter ablation (CA). Time, energy and contact force are parameters related to lesion goodness and incorporated in a complex formula (i.e. the lesion index, LSI™, Abbott). This parameter is emerging as the gold standard for PV isolation. Recently, the shallower but wider lesions created by high power short duration (HPSD) ablation has came to attention.

Purpose

to compare acute reconnection rate, procedural  parameters, and complication rates in patients with paroxysmal or persistent AF undergoing CA.

Methods

one-hundred patients with paroxysmal and 100 with persistent AF will be alternatively assigned to undergo PV isolation with the FlexAbility™ (HPSD group, 70W, 41°, 8 seconds) or the TactiCath™ (LSI-group: 35W, 41°, LSI: 5-5.5 posterior wall, up to ≥6 anywhere else) catheter. A 3-D mapping system (Ensite Precision™) and a steerable sheath (Agilis™, both Abbott) were always used. Adenosine (30mg) is given after PV isolation and ≥ 20 minutes waiting time. Posterior wall isolation was added in all, and patients with persistent AF were additionally treated with mitral and cavotricuspid isthmus ablation. Results: between June and October 2019, 71 patients (68 ± 10 years old, 32 (45%) female, 44 (60%) paroxysmal AF, AF duration 58 ± 81 months) were alternatively assigned to HPSD (36, 51%) or LSI-guided (35, 49%) ablation. No difference in clinical characteristics was found between groups. After 44 ± 18 and 30 ± 14min of procedural and RF time, all PVs were isolated, and all 17 (24%) reconnections treated with an additional 4 ± 3 and 3 ± 2min, respectively. In 8 ± 3 and 7 ± 3 min of procedural and RF time, the PW was successfully isolated in all. PV isolation (34 ± 12min vs. 56 ± 16min; P<.0001), RF (18 ± 5min vs. 41 ± 9min; P<.0001), and total procedural (138 ± 34min vs. 162 ± 34min; P=.0026) time were shorter in the HPSD group. X-Ray time and effective dose did not differ. A similar rate of acute reconnections (9, 25% vs. 8 23%) was found when HPSD and LSI were compared. A higher, although statistically not significant, number of steam pops was observed in the HPSD (14, 39%) vs. LSI (8, 23%) group, possibly related to the higher incidence of moderate pericardial effusion (>0.5mm, <20mm) found the day following the ablation (10, 28% vs. 2, 6%; P=.0238). No further complications related to CA were detected.

Conclusions

in patients with paroxysmal and persistent AF undergoing their first CA, HPSD ablation is faster than an LSI-guided approach. Acute efficacy (reconnection rate) is similar. Although a higher rate of haemodynamically non-relevant pericardial effusions were seen in the HPSD group, these were all treated medically and the general safety profile of this approach is excellent and comparable to LSI ablation.

1247Similar rate of thermal esophageal lesions are found in patients alternatively assigned to high power short duration (70W, 8s) vs. lesion index guided (35W) ablation for atrial fibrillation

Background

wide antral pulmonary vein (PV) catheter ablation (CA) in patients with atrial fibrillation (AF) is safe and effective when permanent trans-mural lesions are achieved without causing harm to surrounding anatomical structures. Atrio-esophageal fistula, due to its high mortality, is the most dreadful complication related to CA for AF, therefore alternative radiofrequency (RF) approaches to reduce or eliminate this complication are currently studied. The shallower but wider lesions of high power short duration (HPSD) ablation might represent a safe alternative.

Purpose

to compare the rate of thermal esophageal lesions in patients with paroxysmal and persistent AF undergoing CA assigned to the 2 different RF modality.

Methods

one-hundred patients with paroxysmal and 100 with persistent AF will be alternatively assigned to undergo CA with the FlexAbility™ (HPSD group: 70W, 41°, 8 seconds) or the TactiCath™ (LSI-group: 35W, 41°, LSI: 5-5.5 posterior wall, up to 6 anywhere else) catheter. A 3-D mapping system, a steerable sheath and adenosine-test (30mg) were used in all patients. Posterior wall (PW) isolation in addition to PV isolation was performed in all, and patients with persistent AF were additionally treated with mitral and cavotricuspid isthmus ablation. Insertion of an esophageal probe was always attempted, and all patients underwent upper endoscopy 24 to 48 hours after CA.

Results

between June and October 2019, 71 patients (68 ± 10 years old, 32 (45%) female, 44 (60%) paroxysmal AF, AF duration 58 ± 81 months) were alternatively assigned to HPSD (36, 51%) or LSI-guided (35, 49%) ablation. No differences in clinical characteristics were found between groups. After 45 ± 18min and 30 ± 14 min of procedural and RF time, all PVs were isolated, and all spontaneous and adenosine-induced reconnections treated. Successful PW isolation was achieved with an additional 8 ± 3 and 7 ± 3 min of procedural and RF time. When HPSD and LSI-guided groups are compared, a similar rate of clinically non-relevant and self-healing thermal lesions at endoscopy was found (10, 27.8% vs. 10, 28.6%). Independent of the treatment group, a higher peak temperature identified patients with esophageal lesions (43.2° vs. 42°; P=.0065). A peak temperature value of 43.1° best identify patients most likely to develop thermal lesions (AUC 0.71, SE 84%, SP 39%). Interestingly, none of the 11 patients in whom esophageal probe insertion was not possible or attempted developed thermal lesions in comparison to 20 (33%) patients who underwent esophageal temperature monitoring (P=.0046). Conclusions: no difference in thermal induced esophageal lesions were found when the two different RF approach (HPSD vs. LSI guided) were compared. Interestingly, lack of temperature monitoring with an esophageal probe is associated with no thermal lesions at endoscopy.

Culex torrentium mosquitoes from Germany are negative for Wolbachia

Wolbachia (Rickettsiales: Anaplasmataceae) infects a wide range of arthropods, including several mosquito species. The bacterium is known to induce a plethora of phenotypes in its host, examples being the reproductive phenotype cytoplasmic incompatibility or resistance against infection with arboviruses. The latter is especially relevant when assessing the vector competence of mosquito species for emerging arboviruses. Thus, knowledge of Wolbachia infection status is important for the assessment of vector competence. To facilitate Wolbachia screening in mosquito populations, a quantitative polymerase chain reaction (qPCR) assay was developed to enable high-throughput analysis of mosquito samples. Using this assay, the Wolbachia infection status of the two most common Culex mosquito species in Germany, Culex pipiens biotype pipiens Linnaeus (Diptera: Culicidae) and Culex torrentium Martini (Diptera: Culicidae), was assessed. About 93% of all tested C. pipiens biotype pipiens individuals were positive for Wolbachia, whereas none of the C. torrentium samples was found to be infected. Furthermore, other applications of the qPCR assay were explored by assessing a potential link between the levels of Wolbachia and West Nile virus (WNV) infections in German C. pipiens biotype pipiens mosquitoes. No relationship was found between the two variables, indicating that a Wolbachia-induced antiviral phenotype in this mosquito population is not exclusively attributable to the general level of bacterial infection.

The Munich MIDY Pig Biobank - A unique resource for studying organ crosstalk in diabetes

OBJECTIVE

The prevalence of diabetes mellitus and associated complications is steadily increasing. As a resource for studying systemic consequences of chronic insulin insufficiency and hyperglycemia, we established a comprehensive biobank of long-term diabetic INSC94Y transgenic pigs, a model of mutant INS gene-induced diabetes of youth (MIDY), and of wild-type (WT) littermates.

METHODS

Female MIDY pigs (n = 4) were maintained with suboptimal insulin treatment for 2 years, together with female WT littermates (n = 5). Plasma insulin, C-peptide and glucagon levels were regularly determined using specific immunoassays. In addition, clinical chemical, targeted metabolomics, and lipidomics analyses were performed. At age 2 years, all pigs were euthanized, necropsied, and a broad spectrum of tissues was taken by systematic uniform random sampling procedures. Total beta cell volume was determined by stereological methods. A pilot proteome analysis of pancreas, liver, and kidney cortex was performed by label free proteomics.

RESULTS

MIDY pigs had elevated fasting plasma glucose and fructosamine concentrations, C-peptide levels that decreased with age and were undetectable at 2 years, and an 82% reduced total beta cell volume compared to WT. Plasma glucagon and beta hydroxybutyrate levels of MIDY pigs were chronically elevated, reflecting hallmarks of poorly controlled diabetes in humans. In total, ∼1900 samples of different body fluids (blood, serum, plasma, urine, cerebrospinal fluid, and synovial fluid) as well as ∼17,000 samples from ∼50 different tissues and organs were preserved to facilitate a plethora of morphological and molecular analyses. Principal component analyses of plasma targeted metabolomics and lipidomics data and of proteome profiles from pancreas, liver, and kidney cortex clearly separated MIDY and WT samples.

CONCLUSIONS

The broad spectrum of well-defined biosamples in the Munich MIDY Pig Biobank that will be available to the scientific community provides a unique resource for systematic studies of organ crosstalk in diabetes in a multi-organ, multi-omics dimension.

Influence of age and gender on complexity measures for short term heart rate variability analysis in healthy subjects

Short-term heart rate variability (HRV) analyses (less than 30 min) are suitable for ambulatory care and patient monitoring and can provide an almost immediate test result. Short-term 5 min HRV indices from nonlinear dynamics were determined from 782 females and 1124 males from the KORA S4 database. We applied various fractal and complexity measures with focus on entropies and investigated the influence of age in terms of five age decades (25-34, 35-44, 45-54, 55-64 and 65-74 years) and gender on these HRV indices. The analyses revealed significant modifications of the indices especially by age but partly also by gender especially in the younger groups. These results should be considered in future studies applying nonlinear dynamics, especially if major age and gender differences between the investigated groups are expected.

[Characteristics of sleep in abstinent alcoholics. A comparison of alcohol- and age-induced reduction of deep sleep]

Polygraphic sleep recordings were performed in 12 sober alcoholic patients, 8 young normals and 12 healthy elderly subjects. An automatic sleep analysis including two different methods (standard and adaptive) of SWS scoring was used. The standard method is based on amplitude dependent rules according to Rechtschaffen and Kales. The basis for classification of SWS in the adaptive method is the relative increase of the integrated delta-activity during NREM sleep. Whereas in young and elderly normal subjects the method used has no influence on the duration of SWS during the night, the amount of SWS in alcoholic patients is significantly higher when applying the adaptive sleep analysis compared with the results of the standard method. Alcoholics show the lowest level of integrated delta activity during NREM and also the shortest duration of SWS resulting from the standard sleep analysis. On the contrary the relative dynamic of EEG synchronization and the duration of SWS measured by the adaptive sleep analysis are comparable with the values of normal subjects. The general decrease of the delta activity during sleep in sober alcoholics is assumed to be not a reflection of the reduction of SWS.

[Automatic sleep analysis--II. Determination of sleep stages]

The presented automatic sleep analysis is based on the time courses of the mean amplitudes of EEG (delta, beta and alpha bands), EMG and motility and specific patterns (spindles, REMs, delta waves greater than 40 microV) detected automatically. The interindividual variability of the parameters is taken into consideration by interactively determining the threshold levels. Sleep stages are classified for every epoch using context free decision rules according to the manual of Rechtschaffen and Kales. The resulting cyclograms are smoothed and corrected using context sensitive rules which considers the successive epochs and the probability of stage transitions.