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Background

The second-generation cryoballoon (CB-A) (Arctic Front Advance, Cryocath, Medtronic, MN, USA) might significantly improve procedural outcome with respect to the first-generation balloon. These technological improvements might also question the current recommendation of the need a 4-min freeze to achieve durable pulmonary vein isolation (PVI).

Objective

The main aim of the study was to analyze the procedural efficacy of a 3-min freeze–thaw cycles with the CB-A balloon in the terms of rates of acute PVI and 6-month outcome.

Methods

Patients having undergone CB-A for PAF or early persistent AF, with 3-min freeze–thaw cycles were consecutively included in our analysis. Acute procedural success was measured in terms of the rate of PVI. Short-term follow-up was evaluated by the means of 24-h Holters and clinical examinations at regular intervals.

Results

Fifty-two consecutive patients (35 male (67 %); mean age, 59.8?±?10.5) were included. Mean procedure and fluoroscopy times were 96?±?15 and 13.2?±?8.3 min, respectively. Mean time from groin puncture to catheter extraction was 60.4?±?20 min. After a mean of 1.5 freeze cycles per vein of 3 min in duration, all 208 (100 %) PVs could be isolated with the CB-A. A total 192 (91 %) veins were isolated during the first freeze. At a mean of 5.7-month follow-up, 82 % of patients were free of AF.

Conclusion

CB-A is effective in producing PVI by using 3-min-duration freeze cycles. After a mean of 1.5 freeze per vein, freedom from AF was achieved in 82 % of patients at 6-month follow-up.  相似文献   
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AIM:To evaluate whether the effectiveness of Granulomonocyto apheresis(GMA),a technique that consists of the extracorporeal removal of granulocytes and monocytes from the peripheral blood,might vary according to the severity of ulcerative colitis(UC)in patients with mild to moderate-severe disease UC activity.METHODS:We retrospectively reviewed prospectively collected data of patients undergoing GMA at our inflammatory bowel disease centre who had at least a 6 mo of follow-up.The demographics,clinical and laboratory data were extracted from the patients’charts and electronic records.The severity of UC was scored according to the Modified Truelove Witts Severity Index(MTWSI).A clinical response was defined as a decrease from baseline of≥2 points or a value of MTWSI≤2 points.RESULTS:A total of 41(24 males/17 females;meanage 47 years)patients were included in the study.After GMA cycle completion,21/28(75%)of mild UC patients showed a clinical response compared with 7/13(54%)of patients with moderate to severe disease(P=0.27).At 6-mo,14/28(50%)of the mild UC patients maintained a clinical response compared with 2/13(15%)of the patients with moderate to severe disease(P=0.04).After the GMA cycle completion and during the 6-mo follow up period,13/16(81%)and 9/16(56%)of mild UC patients with intolerance,resistance and contraindications to immunosuppressants and/or biologics showed a clinical response compared with 2/6(33%)and 0/6(0%)of patients with moderate to severe disease activity with these characteristics(P=0.05and P=0.04,respectively).CONCLUSION:Patients with mild UC benefit from GMA more than patients with moderate to severe disease in the short-term period.GMA should be considered a valid therapeutic option in cases of contraindications to immunosuppressants,corticosteroids and/or biologics.  相似文献   
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Because other coronaviruses enter the cells by binding to dipeptidyl-peptidase-4 (DPP-4), it has been speculated that DPP-4 inhibitors (DPP-4is) may exert an activity against severe acute respiratory syndrome coronavirus 2. In the absence of clinical trial results, we analysed epidemiological data to support or discard such a hypothesis. We retrieved information on exposure to DPP-4is among patients with type 2 diabetes (T2D) hospitalized for COVID-19 at an outbreak hospital in Italy. As a reference, we retrieved information on exposure to DPP-4is among matched patients with T2D in the same region. Of 403 hospitalized COVID-19 patients, 85 had T2D. The rate of exposure to DPP-4is was similar between T2D patients with COVID-19 (10.6%) and 14 857 matched patients in the region (8.8%), or 793 matched patients in the local outpatient clinic (15.4%), 8284 matched patients hospitalized for other reasons (8.5%), and when comparing 71 patients hospitalized for COVID-19 pneumonia (11.3%) with 351 matched patients with pneumonia of another aetiology (10.3%). T2D patients with COVID-19 who were on DPP-4is had a similar disease outcome as those who were not. In summary, we found no evidence that DPP-4is might affect hospitalization for COVID-19.  相似文献   
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Aim: To validate the “platform switching” concept at oral implants with respect to the preservation of the alveolar crestal bone levels in an animal model. Material & methods: Five minipigs received three implants each with a 0.25 mm implant/abutment mismatch and were placed flush (T0), 1 mm below (T1) and 1 mm above (T+1) the alveolar bony crest, and as a control, one conventionally restored implant placed at the bone level. The implants were randomly inserted flapless into the mandible. Four months after implant insertion, the animals were sacrificed, and undecalcified block sections were obtained and used for histological analyses. Results: The mean values for peri‐implant bone resorption were 1.09±0.59 mm (Control), 0.51 (±0.27 mm, T0), 0.50 (±0.46 mm, T+1) and 1.30 (±0.21 mm, T?1), respectively. Statistically significant differences (P<0.05) were found among the test (T0, T?1) and the control sites. Control implants presented an average biologic width length of 3.20 mm (±0.33), with a connective tissue adaptation compartment of 1.29 mm (±0.53) and an epithelial attachment of 1.91 mm (±0.71). T0, T+1 and T?1 implants presented with a mean biologic width of 1.97mm (± 1.20), 2.70mm (± 1.36) and 2.84mm (± 0.90), respectively, with a connective tissue adaptation compartment of 1.21mm (± 0.97), 1.21mm (± 0.65) and 1.50mm (± 0.70) and an epithelial attachment of 0.84mm (± 0.93), 1.66mm (±0.88) and 1.35mm (± 0.44), respectively. Differences between the configurations were mainly associated with the length of the epithelial attachment. The epithelial attachment was significantly longer in the C sites than in T0 (P=0.014). However, no other differences between configurations were detected. Conclusion: If the implants are positioned at the level of the alveolar bony crest, the platform‐switching concept may have a minor impact on the length of the epithelial attachment (0.84 vs. 1.91 mm), while the connective tissue adaptation compartment remains relatively unaffected. Moreover, platform switching resulted in less resorption of the alveolar crest (0.58 mm). To cite this article:
Farronato D, Santoro G, Canullo L, Botticelli D, Maiorana C, Lang NP. Establishment of the epithelial attachment and connective tissue adaptation to implants installed under the concept of “platform switching”: a histologic study in minipigs
Clin. Oral Impl. Res. 23 , 2012; 90–94.
doi: 10.1111/j.1600‐0501.2011.02196.x  相似文献   
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