Population Dynamics and Angler Exploitation of the Unique Muskellunge Population in Shoepack Lake, Voyageurs National Park, Minnesota

A unique population of muskellunge Esox masquinongy inhabits Shoepack Lake in Voyageurs National Park, Minnesota. Little is known about its status, dynamics, and angler exploitation, and there is concern for the long-term viability of this population. We used intensive sampling and mark–recapture methods to quantify abundance, survival, growth, condition, age at maturity and fecundity and angler surveys to quantify angler pressure, catch rates, and exploitation. During our study, heavy rain washed out a dam constructed by beavers Castor canadensis which regulates the water level at the lake outlet, resulting in a nearly 50% reduction in surface area. We estimated a population size of 1,120 adult fish at the beginning of the study. No immediate reduction in population size was detected in response to the loss of lake area, although there was a gradual, but significant, decline in population size over the 2-year study. Adults grew less than 50 mm per year, and relative weight (W r) averaged roughly 80. Anglers were successful in catching, on average, two fish during a full day of angling, but harvest was negligible. Shoepack Lake muskellunge exhibit much slower growth rates and lower condition, but much higher densities and angler catch per unit effort (CPUE), than other muskellunge populations. The unique nature, limited distribution, and location of this population in a national park require special consideration for management. The results of this study provide the basis for assessing the long-term viability of the Shoepack Lake muskellunge population through simulations of long-term population dynamics and genetically effective population size

Rehospitalizations Following Primary Percutaneous Coronary Intervention in Patients With ST-Elevation Myocardial Infarction: Results From a Multi-Center Randomized Trial.

BACKGROUND: Rehospitalizations (RHs) after ST-elevation myocardial infarction carry a high economic burden and may deteriorate quality of life. Characterizing patients at higher risk may allow the design of preventive measures. We studied the frequency, reasons, and predictors for unplanned cardiac and noncardiac RHs in ST-elevation myocardial infarction patients undergoing primary percutaneous coronary intervention. METHODS AND RESULTS: In this post-hoc analysis of the COMFORTABLE AMI (Comparison of Biolimus Eluted From an Erodible Stent Coating With Bare Metal Stents in Acute ST-Elevation Myocardial Infarction; NCT00962416) trial including 1137 patients, unplanned cardiac and noncardiac RHs occurred in 133 (11.7%) and in 79 patients (6.9%), respectively, at 1 year. The most frequent reasons for unplanned cardiac RHs were recurrent chest pain without evidence of ischemia (20.4%), recurrent chest pain with ischemia and coronary intervention (16.9%), and ischemic events (16.9%). Unplanned noncardiac RHs occurred most frequently attributed to bleeding (24.5%), infections (14.3%), and cancer (9.1%). On multivariate analysis, left ventricular ejection fraction (22% increase in the rate of RHs per 10% decrease; P=0.03) and angiographic myocardial infarction Syntax score (34% increase per 10-point increase; P=0.01) were independent predictors of unplanned cardiac RHs. Age emerged as the only independent predictor of unplanned noncardiac RHs. Regional differences for unplanned cardiac RHs were observed. CONCLUSIONS: Among ST-elevation myocardial infarction patients undergoing primary percutaneous coronary intervention in the setting of a randomized, clinical trial, unplanned cardiac RHs occurred in 12% with recurrent chest pain being the foremost reason. Unplanned noncardiac RHs occurred in 7% with bleeding as the leading cause. Left ventricular ejection fraction and Syntax score were independent predictors of unplanned cardiac RHs and identified patient subgroups in need for improved secondary prevention. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00962416

Five-year clinical outcomes and intracoronary imaging findings of the COMFORTABLE AMI trial: randomized comparison of biodegradable polymer-based biolimus-eluting stents with bare-metal stents in patients with acute ST-segment elevation myocardial infarction

AIMS The long-term outcomes of biolimus-eluting stents (BESs) with biodegradable polymer as compared with bare-metal stent (BMS) in patients with ST-segment elevation myocardial infarction (STEMI) remain unknown. METHODS AND RESULTS We performed a 5-year clinical follow-up of 1157 patients (BES: N = 575 and BMS: N = 582) included in the randomized COMFORTABLE AMI trial. Serial intracoronary imaging of stented segments using both intravascular ultrasound (IVUS) and optical coherence tomography performed at baseline and 13 months follow-up were analysed in 103 patients. At 5 years, BES reduced the risk of major adverse cardiac events [MACE; hazard ratio (HR) 0.56, 95% confidence interval (CI): 0.39-0.79, P = 0.001], driven by lower risks for target vessel-related reinfarction (HR 0.44, 95% CI: 0.22-0.87, P = 0.02) and ischaemia-driven target lesion revascularization (HR 0.41, 95% CI: 0.25-0.66, P < 0.001). Definite stent thrombosis (ST) was recorded in 2.2% and 3.9% (HR 0.57, 95% CI: 0.28-1.16, P = 0.12) with no differences in rates of very late definite ST (1.3% vs. 1.6%, P = 0.77). Optical coherence tomography showed no difference in the frequency of malapposed stent struts at follow-up (BES 0.08% vs. BMS 0.02%, P = 0.10). Uncovered stent struts were rarely observed but more frequent in BES (2.1% vs. 0.15%, P < 0.001). In the IVUS analysis, there was no positive remodelling in either group (external elastic membrane area change BES: -0.63 mm2, 95% CI: -1.44 to 0.39 vs. BMS -1.11 mm2, 95% CI: -2.27 to 0.04, P = 0.07). CONCLUSION Compared with BMS, the implantation of biodegradable polymer-coated BES resulted in a lower 5-year rate of MACE in patients with STEMI undergoing primary percutaneous coronary intervention. At 13 months, vascular healing in treated culprit lesions was almost complete irrespective of stent type. CLINICAL TRIAL REGISTRATION http://www.clinicaltrials.gov. Unique identifier: NCT00962416