Arctic Front versus POLARx cryoballoon: Is there a winner?

Since the release of the second-generation cryoballoon (CB2; Arctic Front AdvanceTM, Medtronic Inc) and its modifications with improved cooling characteristics, the technique, dosing, and complication profile is significantly different from that of the first-generation cryoballoon. Several reports of CB2 procedural recommendations have been presented. Hereby, the literature summary was performed and the technical and procedural study based regimen delivered. The best practice overview presents large centers contemporary techniques for safer and more effective outcomes and perhaps new approved recommendations for atrial fibrillation treatment.

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Winter positions of Arctic front during periods of cooling and warming

Journal Ice and Snow ◽

10.15356/2076-6734-2016-4-493-501 ◽

2016 ◽

Vol 56 (4) ◽

pp. 493-501

Author(s):

A. Yu. Mikhailov ◽

A. N. Zolotokrylin ◽

T. B. Titkova

Keyword(s):

Standard Deviation ◽

The Arctic ◽

Horizontal Wind ◽

The North ◽

Arctic Front ◽

The Absolute ◽

Geostrophic Vortex ◽

Climate Cooling ◽

Relative Differences ◽

Geostrophic Advection

Winter positions of the Arctic front (AF) during the known periods of the climate cooling (1949–1980) and warming (1981–2012) were analyzed within the sector 10° W – 60° E. The AF positios were determined by the following indicators: 1) a surface pressure; 2) horizontal wind divergence; 3) geostrophic vortex; 4) geostrophic heat advection. The main extrema of these four dynamic characteristics coincide and fall on the latitude 72.5° N. This corresponds to the average position of the AF for a given resolution and confirms correctness of our choice of these characteristics as the AF indicators. Relative differences between mean profiles of all values of the above warm and cold periods were calculated using method of normalization of each value for the corresponding latitude by the standard deviation for the entire period (1949–2012). To study variability of the AF position we used mean yearly winter profiles of the variables under investigation together with the statistical analysis of positions of the extrema within the latitude degrees. For pressure and geostrophic advection positions of the absolute minima were determined while for geostrophic vortex and divergence – positions of the absolute maxima. The data show that according to different criteria the AF average positions for the period 1949–2012 lie within the zone 72.4–73.4 N. The interannual variability of the AF positions lies within the 1–2 degrees of latitude and corresponds to the range of the air temperature variability above the zone of maximal changes in the sea ice area. According to the standard deviation values of the divergence and the geostrophic vortex are the most stable in region of the AF passage. Comparison of differences of the studied characteristics between the warm and cold periods shows that the changes in the AF positions are not statistically significant (P(t) < 91% t‑criterion) unlike the changes in positions of isolines which characterize the warming (P(t) = 100%). Thus, despite significant changes in properties of the surface and the temperature regime to the north of 72.5 N (the warming), according to all the criteria the AF climatic position remains quasi‑stationary for 32‑year periods of averaging.

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Experience in cryobaloon atrial fibrillation ablation – Polish operators perspective

In a good rythm ◽

10.5604/01.3001.0013.4759 ◽

2019 ◽

Vol 2 (51) ◽

pp. 4-7

Author(s):

Agnieszka Wojdyła-Hordyńska ◽

Jakub Baran ◽

Paweł Derejko

Keyword(s):

Atrial Fibrillation ◽

Second Generation ◽

Pulmonary Veins ◽

Atrial Fibrillation Ablation ◽

Cryoballoon Ablation ◽

Years Of Experience ◽

Technology Changes ◽

Front Advance ◽

Arctic Front ◽

Over 40 Years

The first use of cryoablation in the treatment of arrhythmia has already been described over 40 years ago [1]. Since the introduction of cryoballoon in pulmonary veins isolation in atrial fibrillation treatment, the method has started to attract a lot of interest. Over 350,000 procedures around the word were carried out only by 2018 [2]. Recently, there have been several new publications on the results of second-generation cryoballoon ablation [2, 3, 4]. In view of technology changes, and to summarize years of experience in the treatment of atrial fibrillation, the first Cryousers conference was organized, and held in 2018 in Poland. During this meeting a survey was conducted, obtaining data on the practice of atrial fibrillation treatment in 38 Polish electrophysiological centers performing cryoablation of atrial fibrillation using both balloons, Arctic Front Advance, Medtronic Inc., Minneapolis MN, and radiofrequency point by point ablation. Around 3,745 cryoballoon procedures were performed in the surveyed centers during the year preceding the survey. The survey concerned practical issues related to the qualification and preparation of patients for the procedure, its course, and the results of pulmonary veins isolation in Poland.

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Sources of Springtime Surface Black Carbon in the Arctic: An Adjoint Analysis

10.5194/acp-2016-1112 ◽

2017 ◽

Cited By ~ 1

Author(s):

Ling Qi ◽

Qinbin Li ◽

Daven K. Henze ◽

Hsien-Liang Tseng ◽

Cenlin He

Keyword(s):

Natural Gas ◽

Black Carbon ◽

Biomass Burning ◽

Transport Model ◽

Lower Troposphere ◽

Anthropogenic Sources ◽

The Arctic ◽

Anthropogenic Source ◽

Gas Flaring ◽

Arctic Front

Abstract. We quantify source contributions to springtime (April 2008) surface black carbon (BC) in the Arctic by interpreting surface observations of BC at five receptor sites (Denali, Barrow, Alert, Zeppelin, and Summit) using a global chemical transport model (GEOS-Chem) and its adjoint. Contributions to BC at Barrow, Alert, and Zeppelin are dominated by Asian anthropogenic sources (40–43 %) before April 18 and by Siberian open biomass burning emissions (29–41 %) afterward. In contrast, Summit, a mostly free tropospheric site, has predominantly an Asian anthropogenic source contribution (24–68 %, with an average of 45 %). We compute the adjoint sensitivity of BC concentrations at the five sites during a pollution episode (April 20–25) to global emissions from March 1 to April 25. The associated contributions are the combined results of these sensitivities and BC emissions. Local and regional anthropogenic sources in Alaska are the largest anthropogenic sources of BC at Denali (63 %), and natural gas flaring emissions in the Western Extreme North of Russia (WENR) are the largest anthropogenic sources of BC at Zeppelin (26 %) and Alert (13 %). We find that long-range transport of emissions from Beijing-Tianjin-Hebei (also known as Jing-Jin-Ji), the biggest urbanized region in Northern China, contribute significantly (~ 10 %) to surface BC across the Arctic. On average it takes ~ 12 days for Asian anthropogenic emissions and Siberian biomass burning emissions to reach Arctic lower troposphere, supporting earlier studies. Natural gas flaring emissions from the WENR reach Zeppelin in about a week. We find that episodic, direct transport events dominate BC at Denali (87 %), a site outside the Arctic front, a strong transport barrier. The relative contribution of direct transport to surface BC within the Arctic front is much smaller (~ 50 % at Barrow and Zeppelin and ~ 10 % at Alert). The large contributions from Asian anthropogenic sources are predominately in the form of ‘chronic’ pollution (~ 40 % at Barrow and 65 % at Alert and 57 % at Zeppelin) on 1–2 month timescales. As such, it is likely that previous studies using 5- or 10-day trajectory analyses strongly underestimated the contribution from Asia to surface BC in the Arctic. Both finer temporal resolution of biomass burning emissions and accounting for the Wegener-Bergeron-Findeisen (WBF) process in wet scavenging improve the source attribution estimates.

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507 Is There Utility in Using NAVX With Arctic Front Cryothermal Ablation?

Heart Lung and Circulation ◽

10.1016/j.hlc.2020.09.514 ◽

2020 ◽

Vol 29 ◽

pp. S265

Author(s):

J. Henry

Keyword(s):

Arctic Front ◽

Cryothermal Ablation

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Can Mountain Waves Contribute to Damaging Winds Far Away from the Lee Slope?

Weather and Forecasting ◽

10.1175/waf-d-18-0207.1 ◽

2019 ◽

Vol 34 (6) ◽

pp. 2045-2065 ◽

Cited By ~ 1

Author(s):

Jeffrey D. Kelley ◽

David M. Schultz ◽

Russ S. Schumacher ◽

Dale R. Durran

Keyword(s):

Great Plains ◽

Surface Wind ◽

Surface Friction ◽

Conveyor Belt ◽

The Arctic ◽

Wind Maximum ◽

Mountain Waves ◽

Arctic Front ◽

Strong Winds ◽

Lapse Rates

Abstract On 25 December 2016, a 984-hPa cyclone departed Colorado and moved onto the northern plains, drawing a nearby Arctic front into the circulation and wrapping it cyclonically around the equatorward side of the cyclone. A 130-km-wide and 850-km-long swath of surface winds exceeding 25 m s−1 originated underneath the comma head of the lee cyclone and followed the track of the Arctic front from Colorado to Minnesota. These strong winds formed in association with a downslope windstorm and mountain wave over Colorado and Wyoming, producing an elevated jet of strong winds. Central to the distribution of winds in this case is the Arctic air mass, which both shielded the elevated winds from surface friction behind the front and facilitated the mixing of the elevated jet down to the surface just behind the Arctic front, due to steep lapse rates associated with cold-air advection. The intense circulation south of the cyclone center transported the Arctic front and the elevated jet away from the mountains and out across Great Plains. This case is compared to an otherwise similar cyclone that occurred on 28–29 February 2012 in which a downslope windstorm occurred, but no surface mesoscale wind maximum formed due to the absence of a well-defined Arctic front and postfrontal stable layer. Despite the superficial similarities of this surface wind maximum to a sting jet (e.g., origin in the midtroposphere within the comma head of the cyclone, descent evaporating the comma head, acceleration to the top of the boundary layer, and an existence separate from the cold conveyor belt), this swath of winds was not caused by a sting jet.

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