ISSN:0009-7322    

出版商:OVID    

年代:2003

数据来源: OVID

ISSN:0009-7322    

出版商:OVID    

年代:2003

数据来源: OVID

ISSN:0009-7322    

出版商:OVID    

年代:2003

数据来源: OVID

ISSN:0009-7322    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Abstract—The endothelin (ET) system is comprised of 4 active ETs, with ET-1 being the predominant isoform in the cardiovascular system. Because of the potent vasoconstricting and mitogenic effects of ET-1 and its involvement in various cardiovascular diseases, blockade of the ET receptor has received considerable attention. ET receptor antagonism has been demonstrated to be beneficial in patients with pulmonary hypertension. The nonselective ET receptor antagonist bosentan improves exercise capacity and increases time to clinical worsening in patients with pulmonary arterial hypertension. The selective ET A receptor antagonist sitaxsentan also improves hemodynamics and exercise capacity in patients with pulmonary arterial hypertension. Results with ET receptor antagonists in congestive heart failure have been disappointing. Although some studies have suggested benefit, larger studies have been neutral. The use of ET receptor antagonists for other conditions has not been fully explored. Future studies with the use of ET receptor antagonists as part of a multidrug regimen are also needed.

ISSN:0009-7322    

出版商:OVID    

年代:2003

数据来源: OVID

ISSN:0009-7322    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Background—Recent studies suggested that some HMG-CoA reductase blockers might inhibit the antiplatelet activity of clopidogrel. Therefore, we analyzed how various statins together with a high loading dose of clopidogrel (600 mg) affect platelet aggregation.Methods and Results—Seventy-seven patients with stable angina scheduled for elective coronary stenting were studied. Patients were randomized to receive atorvastatin, fluvastatin, lovastatin, pravastatin, simvastatin (each 20 mg), cerivastatin (0.3 mg), or placebo, plus a high loading dose of 600 mg of clopidogrel. ADP-induced platelet aggregation (5 and 20 &mgr;mol/L) was determined before and 2 and 4 hours after first clopidogrel administration. All patients were taking aspirin (100 mg/d) regularly. We found that none of the statins significantly influenced inhibition of platelet aggregation by clopidogrel.Conclusions—Concomitant use of statins with clopidogrel does not significantly inhibit antiplatelet activity, at least when clopidogrel is administered at a high loading dose of 600 mg.

ISSN:0009-7322    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Background—Thermodilution coronary flow reserve (CFRthermo) is a new technique for invasively measuring coronary flow reserve (CFR) with a coronary pressure wire and is based on the ability of the pressure transducer to also measure temperature changes. Whether CFRthermocorrelates well enough with absolute flow-derived CFR (CFRflow) to replace Doppler wire–derived CFR (CFRDoppler) remains unclear.Methods and Results—In an open-chest pig model, CFRthermowas measured in the left anterior descending (LAD) artery and compared with CFRDopplerand CFRflow, measured with an external flow probe placed around the LAD. In 9 pigs, CFR was measured simultaneously by all 3 means in the normal LAD and after creation of an epicardial LAD stenosis. To determine the added effect of microvascular disease, measurements of flow reserve were also performed after disruption of the coronary microcirculation with embolized microspheres. Intracoronary papaverine (20 mg) was used to induce hyperemia. In a total of 61 paired measurements, CFRthermocorrelated strongly with the reference standard CFRflow(r=0.85,P<0.001). CFRDopplercorrelated less well with CFRflow(r=0.72,P<0.001). Bland-Altman analysis showed a closer agreement between CFRthermoand CFRflow.Conclusion—CFRthermocorrelates better with CFRflowthan does CFRDoppler.

ISSN:0009-7322    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Background—Active compression-decompression (ACD) CPR combined with an inspiratory impedance threshold device (ITD) improves vital organ blood flow during cardiac arrest. This study compared survival rates with ACD+ITD CPR versus standard manual CPR (S-CPR).Methods and Results—A prospective, controlled trial was performed in Mainz, Germany, in which a 2-tiered emergency response included early defibrillation. Patients with out-of-hospital arrest of presumed cardiac pathogenesis were sequentially randomized to ACD+ITD CPR or S-CPR by the advanced life support team after intubation. Rescuers learned which method of CPR to use at the start of each work shift. The primary end point was 1-hour survival after a witnessed arrest. With ACD+ITD CPR (n=103), return of spontaneous circulation and 1- and 24-hour survival rates were 55%, 51%, and 37% versus 37%, 32%, and 22% with S-CPR (n=107) (P=0.016, 0.006, and 0.033, respectively). One- and 24-hour survival rates in witnessed arrests were 55% and 41% with ACD+ITD CPR versus 33% and 23% in control subjects (P=0.011 and 0.019), respectively. One- and 24-hour survival rates in patients with a witnessed arrest in ventricular fibrillation were 68% and 58% after ACD+ITD CPR versus 27% and 23% after S-CPR (P=0.002 and 0.009), respectively. Patients randomized ≥10 minutes after the call for help to the ACD+ITD CPR had a 3 times higher 1-hour survival rate than control subjects (P=0.002). Hospital discharge rates were 18% after ACD+ITD CPR versus 13% in control subjects (P=0.41). In witnessed arrests, overall neurological function trended higher with ACD+ITD CPR versus control subjects (P=0.07).Conclusions—Compared with S-CPR, ACD+ITD CPR significantly improved short-term survival rates for patients with out-of-hospital cardiac arrest. Additional studies are needed to evaluate potential long-term benefits of ACD+ITD CPR.

ISSN:0009-7322    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Background—In patients with coronary artery disease (CAD), acute thrombosis frequently occurs in coronary arteries with only mild or moderate stenoses. Obesity increases the risk of atherosclerosis, but it is not known whether it also increases the risk of coronary thrombosis. We hypothesized that body mass index (BMI) might be an independent predictor of an acute coronary syndrome in patients with established coronary atherosclerosis.Methods and Results—Of 504 patients undergoing coronary angiography, those with evidence of >10% coronary artery stenoses were divided into 2 groups, with either stable (n=226) or unstable CAD (unstable angina or myocardial infarction; n=156). After adjusting for other risk factors (age, gender, blood pressure, lipid levels, insulin resistance, leptin, fibrinogen, C-reactive protein (CRP), CAD severity on angiography, smoking status, and a history of myocardial infarction or hypertension), BMI had a significant independent association with an acute coronary syndrome, with an odds ratio of 1.49 (P=0.014). This positive relation between BMI and the risk of acute coronary events was evident for even mildly elevated BMI values. Multivariate analysis also showed that CRP and the number of coronary lesions were independent predictors of risk of an acute coronary event.Conclusions—In patients with established coronary atherosclerosis, BMI, as well as CRP and number of coronary lesions, are independently associated with acute coronary syndromes. There is evidence of increased risk even at mildly elevated BMI levels.

ISSN:0009-7322    

出版商:OVID    

年代:2003

数据来源: OVID