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Background: Despite 5-7 months of physical inactivity during hibernation, brown bears (Ursus arctos) are able to cope with physiological conditions that would be detrimental to humans. During hibernation, the tissue metabolic demands fall to 25% of the active state. Our objective was to assess cardiac function associated with metabolic depression in the hibernating vs. active states in free-ranging Scandinavian brown bears., Methods: We performed echocardiography on seven free-ranging brown bears in Dalarna, Sweden, anesthetized with medetomidine-zolazepam-tiletamine-ketamine during winter hibernation in February 2013 and with medetomidine-zolazepam-tiletamine during active state in June 2013. We measured cardiac output noninvasively using estimates of hemodynamics obtained by pulsed wave Doppler echocardiography and 2D imaging. Comparisons were made using paired T-tests., Results: During hibernation, all hemodynamic indices were significantly decreased (hibernating vs. active state): mean heart rate was 26.0 (standard deviation (SD): 5.6) beats per min vs. 75.0 (SD: 17.1) per min (P=0.002), mean stroke volume 32.3 (SD: 5.2) ml vs. 47.1 (SD: 7.9) ml (P=0.008), mean cardiac output 0.86 (SD: 0.31) l/min vs. 3.54 (SD: 1.04) l/min (P=0.003), and mean cardiac index 0.63 (SD: 0.21) l/min/kg vs. 2.45 (SD: 0.52) l/min/ m2 (P<0.001). Spontaneous echo contrast was present in all cardiac chambers in all seven bears during hibernation, despite the absence of atrial arrhythmias and valvular disease., Conclusion: Free-ranging brown bears demonstrate hemodynamics comparable to humans during active state, whereas during hibernation, we documented extremely low-flow hemodynamics. Understanding these physiological changes in bears may help to gain insight into the mechanisms of cardiogenic shock and heart failure in humans.

Objectives: This study sought to report the 5-year follow-up results of the Nordic Bifurcation Study., Background: Randomized clinical trials with short-term follow-up have indicated that coronary bifurcation lesions may be optimally treated using the optional side branch stenting strategy., Methods: A total of 413 patients with a coronary bifurcation lesion were randomly assigned to a simple stenting strategy of main vessel (MV) and optional stenting of side branch (SB) or to a complex stenting strategy, namely, stenting of both MV and SB., Results: Five-year clinical follow-up data were available for 404 (98%) patients. The combined safety and efficacy endpoint of cardiac death, non-procedure-related myocardial infarction, and target vessel revascularization were seen in 15.8% in the optional SB stenting group as compared to 21.8% in the MV and SB stenting group (p = 0.15). All-cause death was seen in 5.9% versus 10.4% (p = 0.16) and non-procedure-related myocardial infarction in 4% versus 7.9% (p = 0.09) in the optional SB stenting group versus the MV and SB stenting group, respectively. The rates of target vessel revascularization were 13.4% versus 18.3% (p = 0.14) and the rates of definite stent thrombosis were 3% versus 1.5% (p = 0.31) in the optional SB stenting group versus the MV and SB stenting group, respectively., Conclusions: At 5-year follow-up in the Nordic Bifurcation Study, the clinical outcomes after simple optional side branch stenting remained at least equal to the more complex strategy of planned stenting of both the main vessel and the side branch., (Copyright © 2013 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Background: It is unknown whether the preferred 1-stent bifurcation stenting approach with stenting of the main vessel (MV) and optional side branch stenting using drug-eluting stents should be finalized by a kissing balloon dilatation (FKBD). Therefore, we compared strategies of MV stenting with and without FKBD., Methods and Results: We randomized 477 patients with a bifurcation lesion to FKBD (n=238) or no FKBD (n=239) after MV stenting. The primary end point was major adverse cardiac events: cardiac death, non-procedure-related index lesion myocardial infarction, target lesion revascularization, or stent thrombosis within 6 months. The 6-month major adverse cardiac event rates were 2.1% and 2.5% (P=1.00) in the FKBD and no-FKBD groups, respectively. Procedure and fluoroscopy times were longer and more contrast media was needed in the FKBD group than in the no-FKBD group. Three hundred twenty-six patients had a quantitative coronary assessment. At 8 months, the rate of binary (re)stenosis in the entire bifurcation lesion (MV and side branch) was 11.0% versus 17.3% (P=0.11), in the MV was 3.1% versus 2.5% (P=0.68), and in the side branch was 7.9% versus 15.4% (P=0.039) in the FKBD versus no-FKBD groups, respectively. In patients with true bifurcation lesions, the side branch restenosis rate was 7.6% versus 20.0% (P=0.024) in the FKBD and no-FKBD groups, respectively., Conclusions: MV stenting strategies with and without FKBD were associated with similar clinical outcomes. FKBD reduced angiographic side branch (re)stenosis, especially in patients with true bifurcation lesions. The simple no-FKBD procedures resulted in reduced use of contrast media and shorter procedure and fluoroscopy times. Long-term data on stent thrombosis are needed. Clinical Trial Registration- URL: http://clinicaltrials.gov. Unique identifier: NCT00914199.