Background: Type 2 myocardial infarction (T2MI) occurs because of an acute imbalance in myocardial oxygen supply and demand in the absence of atherothrombosis. Despite being frequently encountered in clinical practice, the population-based incidence and trends remain unknown, and the long-term outcomes are incompletely characterized. Methods: We prospectively recruited residents of Olmsted County, Minnesota, who experienced an event associated with a cardiac troponin T >99th percentile of a normal reference population (≥0.01 ng/mL) between January 1, 2003, and December 31, 2012. Events were retrospectively classified into type 1 myocardial infarction (T1MI, atherothombotic event), T2MI, or myocardial injury (troponin rise not meeting criteria for myocardial infarction [MI]) using the universal definition. Outcomes were long-term all-cause and cardiovascular mortality and recurrent MI. T2MI was further subclassified by the inciting event for supply/demand mismatch. Results: A total of 5460 patients had at least one cardiac troponin T ≥0.01 ng/mL; 1365 of these patients were classified as index T1MI (age, 68.5±14.8 years; 63% male) and 1054 were classified as T2MI (age, 73.7±15.8 years; 46% male). The annual incidence of T1MI decreased markedly from 202 to 84 per 100 000 persons between 2003 and 2012 ( P <0.001), whereas the incidence of T2MI declined from 130 to 78 per 100 000 persons ( P =0.02). In comparison with patients with T1MI, patients with T2MI had higher long-term all-cause mortality after adjustment for age and sex, driven by early and noncardiovascular death. Rates of cardiovascular death were similar after either type of MI (hazard ratio, 0.8 [95% CI, 0.7–1.0], P =0.11). Subclassification of T2MI by cause demonstrated a more favorable prognosis when the principal provoking mechanism was arrhythmia, in comparison with postoperative status, hypotension, anemia, and hypoxia. After index T2MI, the most common MI during follow-up was a recurrent T2MI, whereas the occurrence of a new T1MI was relatively rare (estimated rates at 5 years, 9.7% and 1.7%). Conclusions: There has been an evolution in the type of MI occurring in the community over a decade, with the incidence of T2MI now being similar to T1MI. Mortality after T2MI is higher and driven by early and noncardiovascular death. The provoking mechanism of supply/demand mismatch affects long-term survival. These findings underscore the healthcare burden of T2MI and provide benchmarks for clinical trial design.

Background: There are good data to support using a single high-sensitivity cardiac troponin T (hs-cTnT) below the limit of detection (LoD) of 5 ng/L to exclude acute myocardial infarction. Per the United States (US) Food and Drug Administration (FDA), hs-cTnT can only report to the limit of quantitation (LoQ) of 6 ng/L, a threshold for which there is limited data. Our goal was to determine whether a single hs-cTnT below the LoQ of 6 ng/L is a safe strategy to identify patients at low-risk for acute myocardial injury and infarction. Methods: The efficacy (proportion identified as low-risk based on baseline hs-cTnT<6 ng/L) of identifying low-risk patients was examined in a multicenter (n=22 sites) US cohort study of emergency department patients undergoing at least one hs-cTnT (CV Data Mart Biomarker cohort). We then determined the performance of a single hs-cTnT<6 ng/L (biomarker alone) to exclude acute myocardial injury (subsequent hs-cTnT >99 th percentile in those with an initial hs-cTnT<6 ng/L). The clinically intended rule-out strategy combining a nonischemic electrocardiogram with a baseline hs-cTnT<6 ng/L was subsequently tested in an adjudicated cohort in which the diagnostic performance for ruling-out acute myocardial infarction and safety (myocardial infarction or death at 30-days) were evaluated. Results: A total of 85,610 patients were evaluated in the CV Data Mart Biomarker cohort, amongst which 24,646 (29%) had a baseline hs-cTnT<6 ng/L. Women were more likely than men to have hs-cTnT<6 ng/L (38% vs. 20%, p<0.0001). Among 11,962 patients with baseline hs-cTnT<6 ng/L and serial measurements, only 1.2% developed acute myocardial injury, resulting in a negative predictive value of 98.8% (95% CI 98.6, 99.0) and sensitivity of 99.6% (95% CI 99.5, 99.6). In the adjudicated cohort, a nonischemic electrocardiogram with hs-cTnT<6 ng/L identified 33% of patients (610 of 1849) as low-risk and resulted in a negative predictive value and sensitivity of 100% and a 30-day rate of 0.2% for 30-day myocardial infarction or death. Conclusions: A single hs-cTnT below the LoQ of 6 ng/L is a safe and rapid method to identify a substantial number of patients at very low risk for acute myocardial injury and infarction.

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Summary A multiyear study of pallid sturgeon distribution and relative abundance was conducted in the lower and middle Mississippi river (LMR and MMR, respectively). The LMR and MMR comprise the free‐flowing Mississippi River extending 1857 river kilometers (rkm) from its mouth at the Gulf of Mexico upstream to the mouth of the Missouri River. A total of 219 pallid sturgeon and 6018 shovelnose sturgeon was collected during the periods 1996–1997 and 2000–2006. Trotlines baited with worms were the primary collecting gear. The smallest pallid sturgeon captured on trotlines was 405 mm FL and the largest was 995 mm FL. Mean size of pallid sturgeon was statistically smaller in the Mississippi River below the Atchafalaya River near Baton Rouge, LA (621 mm FL). Mean abundance (catch per trotline night) of pallid sturgeon was highest at water temperatures around 10°C. There was a latitudinal trend in mean abundance of pallid and shovelnose sturgeon, but the pattern differed between species. Pallid sturgeon abundance was statistically (P < 0.05) higher (0.3 fish per trotline night) in the lower reach between the Atchafalaya River and New Orleans (rkm 154–507), and at the Chain of Rocks (COR), a low water dam near the mouth of the Missouri River. Pallid sturgeon abundance between these two locations was statistically the same (0.12–0.23). Shovelnose sturgeon abundance increased going upstream, but was disproportionally higher at the COR (22 fish per line compared with <6 fish per line in other reaches). Overall, the ratio between pallid and shovelnose sturgeon varied from a high of 1 : 6 at the lower reach, and gradually decreased upstream to a low of 1 : 77 at the COR. Based on differences in sturgeon abundance, size and habitat characteristics, the free‐flowing Mississippi River can be divided into two reaches in the MMR (i.e. COR is a separate location), and four reaches (i.e., including the Atchafalaya River) in the LMR where management goals may differ.