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A 500 W SOFC stack provided by Topsoe Fuel Cells A/S was run with reformed diesel fuel for 1,200 h. Diesel fuel used was Swedish Environmental Class 1 containing <10 ppm of sulfur. The fuel was reformed with an autothermal reformer (ATR). The reformer consisted of a mixing chamber and a reactor chamber containing a noble metal catalyst provided by SüdChemie. The reformer used the diesel fuel without any pre-treatment such as sulfur adsorbent. The reformer unit was able to achieve high conversion of reactants with only ppm levels of higher hydrocarbons at the reformer outlet. Particulate emissions of the reformer were measured to be 30 μg m-3, a very low value even below daily exposure limits in ambient air set by the European Comission directives. The stack was first run with 3% humidified H2 + N2 fuel to obtain baseline performance and then switched to reformate. Diesel reformate was found not to induce significantly more long-term degradation on the stack compared to hydrogen case. However, an initial degradation of about 20 mV cell-1 was observed during the first 150 h on diesel fuel reformate. This could be an indication of a poisoning mechanism taking place, but needs further research to be verified. [ABSTRACT FROM AUTHOR]

There is an increasing demand for the results of cardiac markers (troponin I or T, creatine kinase MB mass and myoglobin) to be made available promptly after sample-taking. In order to shorten the turnaround time, the possibility of using EDTA- or heparin-plasma instead of serum was investigated. The study population comprised 391 patients with acute chest pain. Four different instruments and systems routinely used in Finland giving quantitative results were studied for the assays of creatine kinase isoenzyme MB mass, myoglobin, and troponin I or troponin T. In addition to serum samples, heparin-plasma seems to be useful for all three assays using the Access and Immulite systems, while EDTA-plasma seems to be useful for all three assays with the Access and Elecsys systems. For the AxSYM assays, serum samples seem to be the best alternative. In conclusion, it is possible to use a single EDTA- or heparin-plasma sample for Access, Elecsys and Immulite analysers, and thereby to shorten the turnaround time. In this way the quantitative analyses from plasma can be performed 30 min after taking the sample. [ABSTRACT FROM AUTHOR]

Objective: To investigate the time window for ruling out myocardial infarction (MI) with troponin T (TnT) and creatine kinase isoenzyme MB mass (CK-MBm) and the prognosis of patients with ruled-out MI diagnosis.Design: The study was based on 397 patients admitted with a suspected acute coronary syndrome but with relief of symptoms within 24 h.Results: MI diagnosis was confirmed with elevated TnT (>0.10 microg/l) in 108 patients. in 91% within 12-24 h from the onset of symptoms, and in 99% within 12 h from admission. In 94 of these patients CK-MBm became elevated (>5.0 microg/l). in 95% within 10-12 h from the onset of symptoms, and in 99% within 6 h from admission. Among patients with ruled-out MI diagnosis, the 1-year incidence of recurrent coronary events was 29% in those with positive history of coronary heart disease (CHD) but only 7% in those without prior CHD (p < 0.001).Conclusion: Using TnT or CK-MBm, MI can be ruled out within 12 h from admission in the majority of patients. Among patients with ruled-out MI diagnosis, positive history of CHD is an important determinant of prognosis. [ABSTRACT FROM AUTHOR]

Context: Results from recent studies on the effects of beta1-blockade in patients with heart failure demonstrated a 34% reduction in total mortality. However, the effect of beta1-blockade on the frequency of hospitalizations, symptoms, and quality of life in patients with heart failure has not been fully explored.Objective: To examine the effects of the beta1-blocker controlled-release/extended-release metoprolol succinate (metoprolol CR/XL) on mortality, hospitalization, symptoms, and quality of life in patients with heart failure.Design: Randomized, double-blind controlled trial, preceded by a 2-week single-blind placebo run-in period, conducted from February 14, 1997, to October 31, 1998, with a mean follow-up of 1 year.Setting: Three hundred thirteen sites in 14 countries.Participants: Patients (n = 3991) with chronic heart failure, New York Heart Association (NYHA) functional class II to IV, and ejection fraction of 0.40 or less who were stabilized with optimum standard therapy.Interventions: Patients were randomized to metoprolol CR/XL, 25 mg once per day (NYHA class II), or 12.5 mg once per day (NYHA class III or IV), titrated for 6 to 8 weeks up to a target dosage of 200 mg once per day (n = 1990); or matching placebo (n = 2001).Main Outcome Measures: Total mortality or any hospitalization (time to first event), number of hospitalizations for worsening heart failure, and change in NYHA class, by intervention group; quality of life was assessed in a substudy of 741 patients.Results: The incidence of all predefined end points was lower in the metoprolol CR/XL group than in the placebo group, including total mortality or all-cause hospitalizations (the prespecified second primary end point; 641 vs 767 events; risk reduction, 19%; 95% confidence interval [CI], 10%-27%; P<.001); total mortality or hospitalizations due to worsening heart failure (311 vs 439 events; risk reduction, 31%; 95% CI, 20%-40%; P<.001), number of hospitalizations due to worsening heart failure (317 vs 451; P<.001); and number of days in hospital due to worsening heart failure (3401 vs 5303 days; P<.001). NYHA functional class, assessed by physicians, and McMaster Overall Treatment Evaluation score, assessed by patients, both improved in the metoprolol CR/XL group compared with the placebo group (P = .003 and P = .009, respectively).Conclusions: In this study of patients with symptomatic heartfailure, metoprolol CR/XL improved survival, reduced the need for hospitalizations due to worsening heart failure, improved NYHA functional class, and had beneficial effects on patient well-being. [ABSTRACT FROM AUTHOR]

Objective To determine lengths and causes of pre- and in-hospital delays in thrombolytic treatment.Design A prospective national survey covering 48 of the 51 Finnish university, central and general hospitals to obtain basic data before the start of a public campaign to shorten patient-related delay in acute myocardial infarction.Subjects One thousand and twelve consecutive patients with acute myocardial infarction who received thrombolytic therapy over 3 months in 1995 and who represent 40% of all patients with confirmed acute myocardial infarction.Results The median interval between onset of infarction symptoms and initiation of thrombolytic therapy was 160 min (30–647). Only 13% of the patients received thrombolysis within 60 min and 38% within 120 min. The median time from the onset of symptoms to the call for help was 60 min (5–491), and no difference was found in patients with or without a history of previous myocardial infarction (60 and 64 min, respectively). Only 52% of the patients called to the dispatch centre. The median delay from calling for help to hospital arrival was 40 min (10–170). The median in-hospital door-to-needle thrombolysis delay was 40 min (12–196). In 13% of hospitals the median delay was more than 60 min. The emergency physician encountered difficulties in decision making in 33% of cases.Conclusions Only 38% of the patients received thrombolysis within 2 h of onset of symptoms. Patient-related delay before they sought help accounted for the major portion of the total treatment delay. Thus the findings emphasize the importance of prompt action when people are confronted with an acute heart attack. Reorganizing the emergency medical service and emergency department routines is also a necessary target to shorten thrombolysis delays. The delay attributable to transporting patients could be shortened by initiating thrombolytic treatment in the pre-hospital setting. In Finnish hospitals, door-toneedle delay was acceptable in cases with clear indications for thrombolysis. However, emergency physicians often had diagnostic difficulties, which led to remarkably longer in-hospital delays. [ABSTRACT FROM PUBLISHER]

The antiarrhythmic efficacy of mexiletine in acute myocardial infarction (AMI) was studied in 99 patients randomized to mexiletine or placebo treatment. The loading dose was 250 mg i.v. and 400 mg orally followed by 200 mg orally 2 h later, and thereafter 200 mg t.i.d. up to 42 h. Arrhythmias occurring during 48 h were analysed from continuous electrocardiographic recordings. AMI was verified in 35 of 50 mexiletine patients and in 38 of 49 placebo patients. No deaths or instances of ventricular fibrillation occurred in the AMI patients. The number of patients who had any event of accelerated idioventricular rhythm (AIVR; <0.05), runs of ventricular premature beats (VPBs; <0.01), ventricular tachycardia (<0.01) and Ron T beats (<0.05) was smaller in the mexiletine group than in the placebo group. The number of all VPBs (<0.05), hours with occurrence of AIVR (<0.05), runs (<0.01) and Ron T beats (<0.05) was smaller in the mexiletine than in the placebo group. Serum levels of mexiletine tended to be low throughout the study. The half-life of the elimination was 13.7±7.2 h (means±S.D.). Adverse effects were infrequent, and the treatment was well-tolerated. Combined iv. and oral mexiletine prophylaxis significantly suppressed repetitive ventricular tachyarrhythmias and RonT beats. However, no clinical benefit from mexiletine treatment could be shown in a coronary care unit with a low frequency of primary ventricular fibrillation. [ABSTRACT FROM PUBLISHER]

We investigated the difference in the number of myocardial infarction (MI) diagnoses based on troponin T compared with clinical and epidemiologic (modified FINnish Multinational MONItoring of trends and determinants in CArdiovascular diseases) diagnoses, and the prognosis of patients with discordant diagnoses. Five hundred fifty-nine consecutive patients (315 men and 244 women, median age 69 years) were admitted to the hospital with a suspected acute coronary syndrome. Median follow-up time was 17 months. Of the 559 patients, 127 had a clinical and 137 an epidemiologic diagnosis of MI. When a diagnosis of MI was primarily based on troponin T (>0.10 microg/L), the number of MIs was 169, which increased by 33% compared with the number of MIs by clinical diagnosis, and by 23% compared with those by epidemiologic diagnosis. However, troponin T was not elevated in 13% of the 127 patients with the clinical diagnosis and in 14% of the 137 patients with the epidemiologic diagnosis of MI. Among patients in whom clinical diagnosis of MI was not made, the prognosis with regard to coronary death or nonfatal MI was not significantly worse in patients with troponin T >0.10 microg/L than < or =0.10 microg/L (hazard ratio 1.07; 95% confidence interval 0.62 to 1.84). In patients with a suspected acute coronary syndrome, troponin T-based diagnostics leads to an increase in the number of patients diagnosed with MI compared with clinical or epidemiologic diagnosis. The prognostic impact of troponin T in patients without clinical diagnosis of MI based on elevations in conventional enzyme activities needs further study in larger series of patients. [ABSTRACT FROM AUTHOR]

The risk of cerebral infarction in patients with atrial fibrillation varies from 0.5% to more than 10% per year. Anticoagulant therapy is recommended today more than before, but to a low-risk patient anticoagulation may cause harm that is larger than the expected benefit. Assessment of the risk of cerebral infarction is therefore essential. Use of the CHA2DS2-VASc risk index enables reliable identification of low-risk patients who do not benefit from anticoagulation. Individual treatment decisions may even be necessary.

The prevalence and incidence of atrial fibrillation (AF) are increasing rapidly. Key recommendations in management of AF include prompt administration of oral anticoagulation to all patients with elevated risk of thromboembolic complications, proper use of antiarrhythmic drugs and invasive therapies in highly symptomatic patients and adequate rate control in patients with permanent AF. The selection between warfarin and the novel oral anticoagulants (apixaban, dabigatran, rivaroxaban) is based on careful evaluation of the benefits and disadvantages of the drugs in a given patient.

Background: Cardioembolic stroke carries a major risk of stroke recurrence, which can be markedly reduced by early initiation of appropriate secondary prevention. We investigate whether combined examination of the heart, aorta, and cervicocranial arteries with computed tomography (CACC-CT) may improve the diagnosis of stroke etiology., Methods: Patients with suspected cardiogenic ischemic stroke or transient ischemic attack (n = 140; mean age 60 ± 10 years; 95 males) underwent CACC-CT and standard diagnostics including transthoracic and transesophageal echocardiography (TTE/TEE). Patients with atrial fibrillation were excluded because cardiac imaging will not affect to anticoagulant treatment. Imaging findings with a potential cardioembolic source were analyzed. Aortic and cardiac risk findings were evaluated independently. Consensus reading of 2 experts using the findings of both approaches and complemented by cardiac MRI when needed served as the reference standard., Results: In 101 patients (72%) the clinical diagnosis was stroke, and transient ischemic attack was confirmed in the remaining patients. Imaging findings associated with highly increased cardioembolic risk were detected in 22 patients (16%). Nine high-risk findings in 140 patients were found by TTE/TEE and this number rose to 25 high after performing both echocardiography and CACC-CT. No difference was found between CACC-CT and TTE/TEE in detecting patients with of at least one high-risk findings (sensitivity 68 vs. 41%, p = 0.052; specificity 98 vs. 99%; overall accuracy 94 vs. 90%). Combined use of CACC-CT and TTE/TEE was more sensitive than TTE/TEE alone for detecting patients with at least one cardiac or aortic high-risk finding (sensitivity 91 vs. 41%, p < 0.001; specificity 98 vs. 99%; overall accuracy 97 vs. 90%). TTE/TEE was insufficient for diagnosing myocardial infarction with left ventricular aneurysm, whereas the accuracy of CACC-CT was high. In 9 patients (6%) with normal or mild hypokinesia in TTE/TEE, CACC-CT and MRI showed myocardial infarction large enough to indicate anticoagulant therapy. In contrast, CACC-CT was not suitable for diagnosing small left artrial thrombi, patent foramen ovale or to measure left ventricular ejection fraction., Conclusion: CACC-CT and TTE/TEE alone show limited accuracy for the diagnostics of stroke etiology. Therefore, CACC-CT could be a valuable tool in patients with cryptogenic stroke despite standard stroke diagnostics., (Copyright © 2013 S. Karger AG, Basel.)

A major proportion of cardiac patients use long-time antithromobitic medication. It is not uncommon that these patients require surgery and operations. Discontinuation of antithrombotic therapy may be used to decrease risk of hemorrhage, but on the other hand the medication break will make the patient susceptible to thrombotic and thromboembolic complications. The attending physician must decide which is safer: to break the medication or to continue it. Often the best choice is a compromise of the above, i.e. application of a somewhat reduced compensatory antithrombotic therapy.

Background: Atrial fibrillation is common in heart failure, but data regarding beta-blockade in these patients and its ability to prevent new occurrence of atrial fibrillation are scarce., Methods: Baseline ECGs in MERIT-HF were coded regarding baseline rhythm, and outcome was analyzed in relation to rhythm. Occurrence of atrial fibrillation during follow-up was also analyzed., Results: At baseline atrial fibrillation was diagnosed in 556 patients (13.9%). Mean metoprolol CR/XL dose in patients in atrial fibrillation (154 mg) and sinus rhythm (158 mg) was similar, as well as decrease in heart rate (14.8 and 13.7 bpm, respectively). Only 61 (total of 362) deaths occurred in those in atrial fibrillation at baseline, 31 on placebo and 30 on metoprolol (RR 1.0; 95% CI 0.61-1.65). During follow-up, new atrial fibrillation was observed in 85 patients on placebo and 47 patients on metoprolol (RR 0.53; 95% CI 0.37-0.76; p=0.0005)., Conclusion: First, given the wide confidence interval, it was impossible to detect an interaction between metoprolol and mortality in patients with atrial fibrillation and heart failure. Second, in patients with sinus rhythm at baseline, metoprolol reduced the incidence of atrial fibrillation during follow-up. However, we must be extremely cautious in over-interpreting effects in these subgroups.

Objectives: The aim of the study was to evaluate the validity of the systematic reviews as a source of best evidence and to present and interpret the evidence of the systematic reviews on effectiveness of surgery and percutaneous interventions for stable coronary artery disease., Methods: Electronic databases were searched without language restriction from January 1966 to March 2004. The databases used included the Cochrane Database of Systematic Reviews, the Cochrane Central Register of Controlled Trials, DARE, the Health Technology Assessment Database, MEDLINE(R), MEDLINE(R) In-Process & Other Non-Indexed Citations. We included systematic reviews of randomized clinical trials on patients with stable coronary heart disease undergoing percutaneous coronary intervention or coronary artery bypass surgery in comparison with medical treatment or a comparison between invasive techniques. At least one of the following outcomes had to be reported: death, myocardial infarction, angina pectoris, revascularization. The methodological quality was assessed using a modified version of the scale devised by Oxman and Guyatt (1991). A standardized data-extraction form was used. The method used to evaluate clinical relevance was carried out with updated method guidelines from the Cochrane Back Research Group. Quantitative synthesis of the effectiveness data is presented., Results: We found nineteen systematic reviews. The median score of validity was 13 points (range, 6-17 points), with a maximum of 18 points. Coronary artery bypass surgery gives better relief of angina, and the need for repeated procedures is reduced after bypass surgery compared with percutaneous interventions. There is inconsistent evidence as to whether bypass surgery improves survival compared with percutaneous intervention. A smaller need for repeated procedures exists after bare metal stent and even more so after drug-eluting stent placement than after percutaneous intervention without stent placement. However, according to the current evidence, these treatment alternatives do not differ in terms of mortality or myocardial infarction., Conclusions: We found some high-quality systematic reviews. There was evidence on the potential of invasive treatments to provide symptomatic relief. Surgery seems to provide a longer-lasting effect than percutaneous interventions with bare metal stents or without stents. Evidence in favor of drug-eluting stents so far is based on short-term follow-up and mostly on patients with single-vessel disease.