Prolonged drying trend coincident with the demise of Norse settlement in southern Greenland.

Declining temperature has been thought to explain the abandonment of Norse settlements, southern Greenland, in the early 15th century, although limited paleoclimate evidence is available from the inner settlement region itself. Here, we reconstruct the temperature and hydroclimate history from lake sediments at a site adjacent to a former Norse farm. We find no substantial temperature changes during the settlement period but rather that the region experienced a persistent drying trend, which peaked in the 16th century. Drier climate would have notably reduced grass production, which was essential for livestock overwintering, and this drying trend is concurrent with a Norse diet shift. We conclude that increasingly dry conditions played a more important role in undermining the viability of the Eastern Settlement than minor temperature changes.

Multivessel percutaneous coronary intervention in patients with multivessel disease and acute myocardial infarction.

BACKGROUND: The optimal percutaneous interventional strategy for dealing with significant non-culprit lesions in patients with multivessel disease (MVD) with acute myocardial infarction (AMI) at presentation remains controversial. METHODS: A total of 820 patients treated with primary angioplasty for AMI between 1998 and 2002 were classified in groups of patients with single vessel disease (SVD) or MVD (> or =70% stenosis of > or =2 coronary arteries). Patients with MVD were subdivided in 3 groups on the basis of the revascularization strategy: 1) patients undergoing percutaneous coronary intervention (PCI) of the infarct-related artery (IRA) only; 2) patients undergoing PCI of both the IRA and non-IRA(s) during the initial procedure; and 3) patients undergoing PCI of the IRA followed by staged, in-hospital PCI of the non-IRA(s). Procedural, 30-day, and 1-year outcomes are reported. RESULTS: At 1 year, compared with patients with SVD, patients with MVD had a higher incidence of re-infarction (5.9% vs 1.6%, P =.003), revascularization (18% vs 9.6%, P <.001), mortality (12% vs 3.2%, P <.001), and major adverse cardiac events (MACEs; 31% vs 13%, P <.001). In patients with MVD, compared with PCI restricted to the IRA only, multivessel PCI was associated with higher rates of re-infarction (13.0% vs 2.8%, P <.001), revascularization (25% vs 15%, P =.007), and MACEs (40% vs 28%, P =.006). Multivessel PCI was an independent predictor of MACEs at 1 year (odds ratio = 1.67, P =.01). CONCLUSIONS: These data suggest that in patients with MVD, PCI should be directed at the IRA only, with decisions about PCI of non-culprit lesions guided by objective evidence of residual ischemia at late follow-up. Further studies are needed to confirm these findings.