摘要:

Background HMG CoA reductase inhibitors (or statins), a new class of lipid-lowering compounds, have raised expectations for more widespread use than that of the older lipid-lowering drugs. Not only are they more effective in lowering LDL cholesterol, but they are better tolerated as well. No data exist concerning the effect of statins on early carotid atherosclerosis and clinical events in men and women who have moderately elevated LDL cholesterol levels but are free of symptomatic cardiovascular disease.Methods and Results Lovastatin (20 to 40 mg/d) or its placebo was evaluated in a double-blind, randomized clinical trial with factorial design along with warfarin (1 mg/d) or its placebo. This report is limited to the lovastatin component of the trial. Daily aspirin (81 mg/d) was recommended for everyone. Enrollment included 919 asymptomatic men and women, 40 to 79 years old, with early carotid atherosclerosis as defined by B-mode ultrasonography and LDL cholesterol between the 60th and 90th percentiles. The 3-year change in mean maximum intimal-medial thickness (IMT) in 12 walls of the carotid arteries was the primary outcome; change in single maximum IMT and incidence of major cardiovascular events were secondary outcomes. LDL cholesterol fell 28%, from 156.6 mg/dL at baseline to 113.1 mg/dL at 6 months (P<.0001), in the lovastatin groups and was largely unchanged in the lovastatin-placebo groups. Among participants not on warfarin, regression of the mean maximum IMT was seen after 12 months in the lovastatin group compared with the placebo group; the 3-year difference was statistically significant (P=.001). A larger favorable effect of lovastatin was observed for the change in single maximum IMT but was not statistically significant (P=.12). Five lovastatin-treated participants suffered major cardiovascular events--coronary heart disease mortality, nonfatal myocardial infarction, or stroke--versus 14 in the lovastatin-placebo groups (P=.04). One lovastatin-treated participant died, compared with eight on lovastatin-placebo (P=.02).Conclusions In men and women with moderately elevated LDL cholesterol, lovastatin reverses progression of IMT in the carotid arteries and appears to reduce the risk of major cardiovascular events and mortality. Results from ongoing large-scale clinical trials may further establish the clinical benefit of statins. (Circulation. 1994;90:1679-1687.)

ISSN:0009-7322    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

Background Sinking prebeta lipoprotein is a putative marker for elevated levels of lipoprotein (a). Although prospective data suggest that increased plasma lipoprotein (a) is an independent risk factor for coronary heart disease in men, no prospective studies are available in women.30 mg/dL, the threshold value linked to increased cardiovascular disease risk in men.Conclusions Sinking prebeta lipoprotein was a valid surrogate for elevated lipoprotein (a) levels in Framingham Heart Study women. Band presence and, equivalently, elevated plasma lipoprotein (a), was a strong, independent predictor of myocardial infarction, intermittent claudication, and cerebrovascular disease. Confirmation of these findings in other longitudinal studies of women is needed. (Circulation. 1994;90:1688-1695.)

ISSN:0009-7322    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

Background Recent evidence suggests that, in coronary artery disease (CAD), myocardial blood flow (MBF) regulation is abnormal in regions supplied by apparently normal coronary arteries. However, the relation between this alteration and MBF response to increasing metabolic demand has not been fully elucidated.=50% diameter narrowing). Perfusion of both poststenotic (S) and normally supplied (N) areas was measured off therapy by positron emission tomography and (Nitrogen-13)ammonia. Normal subjects and CAD patients showed similar rate-pressure products at baseline, during pacing, and after dipyridamole. In CAD patients, MBF was lower in S than in N territories at rest (0.68+-0.14 versus 0.74+-0.18 mL x min sup -1 x g sup -1, respectively, P<.05), during pacing (0.92+-0.29 versus 1.16+-0.40 mL x min sup -1 x g sup -1, respectively, P<.01), and after dipyridamole (1.18+-0.34 versus 1.77+-0.71 mL x min sup -1 x g sup -1, respectively, P<.01). However, normal subjects showed significantly higher values of MBF both at rest (0.92+-0.13 mL x min sup -1 x g sup -1, P<.05 versus both S and N areas), during pacing tachycardia (1.95+-0.64 mL x min sup -1 x g sup -1, P<.01 versus both S and N areas), and after dipyridamole (3.59+-0.71 mL x min sup -1 x g sup -1, P<.01 versus both S and N areas). The percent change in flow was strictly correlated with the corresponding change in rate-pressure product in normal subjects (r=.85, P<.01) but not in either S (r=.04, P=NS) or N regions (r=.08, P=NS) of CAD patients.Conclusions Besides epicardial stenosis, further factors may affect flow response to increasing metabolic demand and coronary reserve in patients with CAD. (Circulation. 1994;90:1696-1705.)

ISSN:0009-7322    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

Background After successful thrombolysis for acute myocardial infarction, reocclusion is observed in about 30% of patients after 3 months and usually occurs without reinfarction. We studied the impact of reocclusion without reinfarction on global and regional left ventricular function and on remodeling during that period.Methods and Results The patients for this analysis constituted a subset of those enrolled in the APRICOT-trial, which was designed to study the efficacy of antithrombotics on the prevention of reocclusion. Patients were selected who had a left anterior descending- or right coronary artery-related myocardial infarction, had an angiographically patent infarct-related vessel when studied <48 hours after intravenous thrombolysis, and underwent repeat cardiac catheterization at 3 months. Paired contrast ventriculograms of quality sufficient to analyze regional wall motion, global ejection fraction, and ventricular volumes were analyzed in 129 patients. Enzymatic infarct size and baseline left ventricular function as well as other baseline characteristics were similar in patients with (n=34) and without (n=95) reocclusion. Ejection fraction improved in anterior infarction without reocclusion from 47+-10% to 54+-13% (P=.0001) but not with reocclusion (baseline, 48+-13%; 3 months, 48+-16%). No improvement was seen in inferior infarction with or without reocclusion. Persistent patency allowed preservation of end-systolic volume index (ESVI) at 3 months (37+-14 mL/m2) to baseline level (38+-13 mL/m210 mL/m240 mL/m2. After reocclusion, in contrast, ESVI increased from 37+-14 to 43+-20 mL/m2(P=.08). Comparable mean changes of ESVI in response to persistent patency or reocclusion were seen in anterior versus inferior infarction. Recovery of infarct zone contractility was impaired by reocclusion, both in terms of abnormality of segment shortening and expressed in the number of segments showing abnormal wall motion. In anterior but not in inferior infarction, infarct zone contractility was better with good collaterals to the reoccluded artery compared with poor collaterals.Conclusions After successful thrombolysis for acute myocardial infarction, reocclusion without reinfarction withholds salvaged myocardium from regaining contractility. This has deleterious consequences for regional and global left ventricular function and for remodeling. To further optimize prognosis in patients after thrombolysis, future research should focus on the prevention of reocclusion and should evaluate revascularization therapy in patients with reocclusion. (Circulation. 1994;90:1706-1714.)

ISSN:0009-7322    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

Background We wished to evaluate whether differences in the rate of invasive cardiac procedures between men and women with acute myocardial infarction are associated with different short- and long-term mortality.Methods and Results The database (Myocardial Infarction Data Acquisition System, MIDAS) included all discharges for the years 1986 and 1987 with the diagnosis of acute myocardial infarction in New Jersey, based on the New Jersey hospital discharge data system (MIDS/UB-82). Accuracy of the data was evaluated by auditing 726 randomly selected charts. The variables examined included age, sex, race, comorbidity (anemia, chronic liver disease, cancer, chronic obstructive pulmonary disease, diabetes, hypertension, prior myocardial infarction), complications (left ventricular dysfunction, arrhythmias, conduction defects), insurance status, performance of cardiac catheterization, percutaneous transluminal coronary angioplasty, or coronary artery bypass graft surgery, and survival up to 3 years. Women were older, had longer hospital stay, and were more likely than men to have anemia, diabetes, hypertension, left ventricular dysfunction, and Medicare or Medicaid insurance coverage. They were less likely than men to be admitted to a hospital equipped to perform invasive procedures or to have chronic obstructive pulmonary disease, chronic liver disease, prior myocardial infarction, or arrhythmias. After adjustment for these differences, women were less likely than men to have cardiac catheterization. Cardiac catheterization was associated with lower mortality. Women up to age 70 had higher 3-year death rates than men after adjustment for age, race, comorbidity, complications, and insurance type. This difference between men and women was somewhat diminished after the performance of cardiac catheterization and revascularization was taken into account. Unadjusted mortality was high in this study group.Conclusions Women with acute myocardial infarction are less likely to have invasive cardiac procedures and have higher 3-year adjusted death rate up to age 70 than men. (Circulation. 1994;90:1715-1730.)

ISSN:0009-7322    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

Background In the Survival and Ventricular Enlargement (SAVE) trial, recurrent myocardial infarction (MI) was the most important predictor of a poor outcome and conferred a sevenfold increase in risk of death. The purpose of this study was to determine the predictors of recurrent MI in study participants and to examine the influence of the angiotensin- converting enzyme inhibitor captopril on this and other myocardial ischemic events.Methods and Results The 2231 patients had survived the acute phase of MI (3 to 16 days) and had a radionuclide ventricular ejection fraction <=40%. Patients were randomly assigned to receive double-blind treatment with either placebo or captopril and were followed for an average of 42 months. The influence of captopril on recurrent MI, cardiac revascularization procedures, and hospitalization with unstable angina was examined. The likelihood of recurrent MI was greater in patients with an MI or functional disability before the index infarction and higher systolic pressure (all P<.001) but was not influenced by baseline left ventricular ejection fraction. Therapy with captopril reduced the risk of development of recurrent MI by 25% (95% confidence intervals, 5% to 40%; P=.015) and the risk of death after recurrent MI by 32% (95% confidence intervals, 4% to 51%; P=.029). Captopril-assigned patients were also less likely to require cardiac revascularization procedures (P=.010), but hospitalization for unstable angina was unaltered. When all three of these major coronary ischemic events were considered together, captopril therapy reduced the risk (14% risk reduction; 95% confidence intervals, 0% to 26%; P=.047).Conclusions In post-MI patients with asymptomatic left ventricular dysfunction, long-term administration of captopril reduced recurrence of MI and the need for cardiac revascularization but had no influence on the rate of hospitalization with a discharge diagnosis of unstable angina. The finding that the recurrence of MI was independent of left ventricular ejection fraction suggests that captopril could be useful in preventing recurrent MI in patients with more preserved left ventricular function. The need for cardiac revascularization was reduced in patients receiving long-term captopril therapy, suggesting either an anti-ischemic effect or the ability of the angiotensin-converting enzyme inhibitor to modify the atherosclerotic process in survivors of MI. (Circulation. 1994;90: 1731-1738.)

ISSN:0009-7322    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

Background The purpose of this study was to determine differences in coronary stenosis severity and morphology and time course of progression between Q-wave and non-Q-wave myocardial infarction (MI).70%) was typically present.Conclusions The atheromatous plaque substrate is different in Q-wave and non-Q-wave MI. Non-Q-wave MI occurs typically at a site shown by pre-MI angiography to involve either minimal luminal narrowing or a severe stenosis before MI, which is usually nonulcerated. By comparison, Q-wave MI follows a moderate stenosis in which the plaque is eccentric and ulcerated. Such differences culminate in differences in thrombus lability and collateral development and consequently in different clinical profiles. (Circulation. 1994;90: 1739-1746.)

ISSN:0009-7322    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

Background Successful reperfusion of the infarct-related artery in patients with acute myocardial infarction has been shown to reduce in-hospital as well as 1-year mortality. Besides the thrombolysis-induced myocardial salvage, there is increasing evidence that an open infarct-related artery results in increased electrical stability of the heart and that this effect is at least in part responsible for the favorable long-term outcome of these patients. The exact incidence of arrhythmic events during the first year after myocardial infarction and the predictive value of different risk factors for these complications, however, have not been determined in patients in the thrombolytic era.Methods and Results A total of 173 patients with acute myocardial infarction, 51% treated with thrombolysis, were prospectively entered into the study. At the time of hospital discharge, signal-averaged ECG, Holter monitoring, radionuclide angiography, coronary angiography, and levocardiography were performed in all patients. An open infarct-related artery was documented in 136 patients. The overall incidence of late potentials was 24% (41 patients). By multivariate analysis, an occluded infarct-related artery (P=.04) and the presence of regional wall motion abnormalities (P=.02) were the strongest independent predictors for the development of a late potential. Residual ischemia was treated by either percutaneous transluminal coronary angioplasty or surgery in 86 of 173 patients (50%). Seventy percent of the patients received beta -blocker therapy. During a mean follow-up of 12+-5 months, 7 patients died suddenly or had ventricular fibrillation documented, while only 2 developed sustained monomorphic ventricular tachycardia. Overall 1-year mortality was 4.1%. Multivariate analysis revealed only an occluded infarct-related artery as an independent predictor of arrhythmic complications (P=.017).Conclusions In patients with acute myocardial infarction treated according to contemporary therapeutic guidelines, with a large proportion of individuals undergoing coronary artery revascularization, a low incidence of arrhythmic events, particularly of ventricular tachycardia, was observed in the first year after the index infarction. The presence or absence of an open infarct-related artery was the strongest independent predictor of these events, whereas other traditional risk factors, such as late potentials, were less helpful in identifying patients prone to sudden death. These findings emphasize the importance of the open artery hypothesis in patients recovering from acute myocardial infarction. (Circulation. 1994;90: 1747-1756.)

ISSN:0009-7322    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

Background Thrombosis has been implicated as central to the clinical complications of coronary angioplasty (PTCA). Chimeric monoclonal 7E3 Fab (c7E3 Fab) is the first of a new class of antiplatelet drugs directed at the platelet glycoprotein IIb/IIIa integrin. This study was performed to determine the pharmacodynamics of c7E3 Fab administration during PTCA and to gain an initial clinical experience with this novel agent.80% of the receptors and reduce platelet aggregation to <20% compared with baseline, establishing this dose as that necessary to sufficiently suppress platelet activity. In stage 2, additional c7E3 Fab was administered by continuous infusion to 32 patients for progressively longer periods of time (up to 24 hours) to confirm that platelet inhibition could be maintained with prolonged drug infusion. Also, 9 patients otherwise meeting entry criteria were given placebo. There were no thrombotic events among patients receiving c7E3 Fab. Overall procedural and clinical success and complication rates as well as rates of bleeding were statistically similar among groups. However, minor bleeding was more frequent with administration of the active drug.Conclusions The novel antiplatelet agent c7E3 Fab can be administered during PTCA in combination with aspirin and heparin. Suppression of platelet activity is dose dependent and can be maintained for up to 24 hours. Further evaluation will be required to determine the extent of improvement in ischemic complication and restenosis rates and to provide additional insight into the safety profile of this potent monoclonal platelet antibody. (Circulation. 1994;90:1757-1764.)

ISSN:0009-7322    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

Background Functional benefit in heart failure due to idiopathic dilated cardiomyopathy has been observed after beta -blockade, but improvement in survival has not been established in a large-scale randomized trial. This was the main objective of the Cardiac Insufficiency Bisoprolol Study (CIBIS).Methods and Results Six hundred forty-one patients with chronic heart failure of various etiologies and a left ventricular ejection fraction of <40% entered this placebo-controlled, randomized, double-blind study. Patients were in New York Heart Association functional class III (95%) or IV (5%) at inclusion. All received background diuretic and vasodilator therapy (an angiotensin-converting enzyme inhibitor in 90% of cases). A total of 320 patients was randomized to bisoprolol and 321 to placebo. Mean follow-up was 1.9 years. Bisoprolol was well tolerated without between group difference in premature treatment withdrawals (82 on placebo, 75 on bisoprolol; NS). The observed difference in mortality between groups did not reach statistical significance: 67 patients died on placebo, 53 on bisoprolol (P=.22; relative risk, 0.80; 95% confidence interval, 0.56 to 1.15). No significant difference was observed in sudden death rate (17 on placebo, 15 on bisoprolol) or death related to documented ventricular tachycardia or fibrillation (7 on placebo, 4 on bisoprolol). Bisoprolol significantly improved the functional status of the patients; fewer patients in the bisoprolol group required hospitalization for cardiac decompensation (90 on placebo versus 61 on bisoprolol, P<.01), and more patients improved by at least one New York Heart Association functional class (48 on placebo versus 68 on bisoprolol, P=.04) by the end of follow-up period.Conclusions These results confirm previous trials evidence that a progressively increasing dose of beta -blocker in severe heart failure confers functional benefit. Subgroup analysis suggested that benefit from beta -blockade therapy was greater for those with nonischemic cardiomyopathy. However, improvement in survival while on beta -blockade remains to be demonstrated. (Circulation. 1994;90:1765-1773.)

ISSN:0009-7322    

出版商:OVID    

年代:1994

数据来源: OVID