Near-infrared spectrophotometry-determined cerebral (ScO2) and muscle oxygen saturations (SmO2) were followed in 15 volunteers during passive 50 degrees head-up-tilt-induced central hypovolaemia, and in nine volunteers during ventilatory manoeuvres affecting arterial carbon dioxide tension. During head-up tilt, mean arterial pressure [MAP, 88 (77-118) to 97 (80-136) mmHg, median and range] and heart rate [HR; 66 (49-77) to 87 (42-132) beats min-1 P < 0.01] increased, but after 22 (1-45) min they declined [to 61 (40-91) mmHg and 69 (38-109) beats min-1, respectively, P = 0.001] and pre-syncopal symptoms developed. Central hypovolaemia was indicated by an increased thoracic electrical impedance, and a decreased cardiac output and central venous oxygen saturation. The arterial oxygen saturation, pulmonal oxygen uptake and skin temperatures remained constant. The ScO2 remained stable at 72 (62-77)% until the pre-syncopal incidence, when it decreased to 62 (31-73)% (P = 0.001), and tilt down made it increase to 75 (36-87)% (P < 0.05) before the recovery value was established. In contrast, SmO2 decreased during tilting [75(70-87) to 65 (53-70)%], and recovered to 70 (53-83)%, P < 0.01) during the hypotensive episode. The end-tidal CO2 tension decreased only during tilt-up. The ScO2 decreased, and SmO2 increased during hyperventilation, and ScO2 increased during breathing of 5% carbon dioxide. Rebreathing from a bag made SmO2 decrease and resulted in a biphasic ScO2 response: it first increased and subsequently decreased. Cardiovascular changes during tilt were not reflected in skin temperature. The ScO2 reflected the maintained autoregulation of cerebral blood flow until the perfusion pressure decreased markedly. In contrast, SmO2 mirrored muscle vasoconstriction early during tilt, and vasodilatation when pre-syncopal symptoms appeared.

Background: The aim of this prospective survey was to describe the demographics, stroke risk profile, and the guideline adherence of antithrombotic treatment in a Danish primary care population of patients with nonvalvular atrial fibrillation (AF). Hypothesis: We hypothesized that a significant proportion of patients with nonvalvular AF do not receive guideline-adherent antithrombotic treatment in primary care. Methods: We performed a cross-sectional survey of antithrombotic treatment using data of AF patients from general practices. Results: Sixty-four general practitioners enrolled 1743 patients with a mean age of 74.8 ± 11.2 years. The mean CHADS 2 and CHA 2 DS 2 -VASc scores were 1.9 ± 1.3 and 3.5 ± 1.8, respectively. Of the patients, 12.4% and 4.04%, respectively, were at truly low risk, with a CHADS 2 and CHA 2 DS 2 -VASc score 0 (P < 0.001). A score of 1 was seen in 28.0% vs 9.0% (P < 0.001) of the patients. Of all patients, 66.3% were treated with oral anticoagulants, 18.7% with antiplatelet drugs only, and 15% received no antithrombotic therapy. Based on the CHADS 2 score, 75.7% of the patients were treated in adherence with the guidelines, 16% were undertreated, and 8.4% overtreated. The corresponding numbers for the CHA 2 DS 2 -VASc score were 75.4%, 22.7%, and 1.8%, respectively. The differences in guideline adherence applying the 2 scores were significant (P < 0.001). Of patients receiving no antithrombotic therapy, 64.1% were treated in adherence to the guidelines according to the CHADS 2 score. Applying the CHA 2 DS 2 -VASc score, this proportion was only 53.4%. Antiplatelet drug treatment was in adherence to the guidelines (CHADS 2 and CHA 2 DS 2 -VASc score of 1) in only 31% and 12% of the patients, respectively. Conclusions: Antithrombotic treatment of AF patients is in general well performed in primary care in Denmark. Further improvements may be achieved by thorough stroke risk stratification on the basis of current evidence-based guidelines.

The present study was performed to test the hypothesis that patients with a large amount of ischemic (hibernating) myocardium are most likely to develop a perioperative myocardial infarction undergoing coronary artery bypass grafting (CABG). Furthermore, we evaluated the Selvester QRS scoring system as a postoperative prognostic tool. A relationship between a high amount of hibernating myocardium determined by ventriculographic and electrocardiographic investigations and an increased risk of perioperative myocardial infarction was found. The Selvester QRS scoring system used in diagnosing and prognosing after acute myocardial infarction was proven valid in predicting prognosis after CABG as well.