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Context: beta-blockers are underused in patients who have myocardial infarction (MI), despite the proven efficacy of these agents. New evidence indicates that beta-blockers can have benefit in patients with conditions that have been considered relative contraindications. Understanding the consequences of underuse of beta-blockers is important because of the implications for current policy debates over quality-of-care measures and Medicare prescription drug coverage.Objective: To examine the potential health and economic impact of increased use of beta-blockers in patients who have had MI.Design and Setting: We used the Coronary Heart Disease (CHD) Policy Model, a computer-simulation Markov model of CHD in the US population, to estimate the epidemiological impact and cost-effectiveness of increased beta-blocker use from current to target levels among survivors of MI aged 35 to 84 years. Simulations included 1 cohort of MI survivors in 2000 followed up for 20 years and 20 successive annual cohorts of all first-MI survivors in 2000-2020. Mortality and morbidity from CHD were derived from published meta-analyses and recent studies. This analysis used a societal perspective.Main Outcome Measures: Prevented MIs, CHD mortality, life-years gained, and cost per quality-adjusted life-year (QALY) gained in 2000-2020.Results: Initiating beta-blocker use for all MI survivors except those with absolute contraindications in 2000 and continuing treatment for 20 years would result in 4300 fewer CHD deaths, 3500 MIs prevented, and 45,000 life-years gained compared with current use. The incremental cost per QALY gained would be $4500. If this increase in beta-blocker use were implemented in all first-MI survivors annually over 20 years, beta-blockers would save $18 million and result in 72,000 fewer CHD deaths, 62,000 MIs prevented, and 447,000 life-years gained. Sensitivity analyses demonstrated that the cost-effectiveness of beta-blocker therapy would always be less than $11,000 per QALY gained, even under unfavorable assumptions, and may even be cost saving. Restricting beta-blockers only to ideal patients (those without absolute or relative contraindications) would reduce the epidemiological impact of beta-blocker therapy by about 60%.Conclusions: Our simulation indicates that increased use of beta-blockers after MI would lead to impressive gains in health and would be potentially cost saving. JAMA. 2000;284:2748-2754. [ABSTRACT FROM AUTHOR]

Context: Lipoprotein(a) [Lp(a)] has been identified as an independent risk factor for coronary heart disease (CHD) events. However, few data exist on the clinical importance of Lp(a) lowering for CHD prevention. Hormone therapy with estrogen has been found to lower Lp(a) levels in women.Objective: To determine the relationships among treatment with estrogen and progestin, serum Lp(a) levels, and subsequent CHD events in postmenopausal women.Design and Setting: The Heart and Estrogen/progestin Replacement Study (HERS), a randomized, blinded, placebo-controlled secondary prevention trial conducted from January 1993 through July 1998 with a mean follow-up of 4.1 years at 20 centers.Participants: A total of 2763 postmenopausal women younger than 80 years with coronary artery disease and an intact uterus. Mean age was 66.7 years.Intervention: Participants were randomly assigned to receive either conjugated equine estrogens, 0.625 mg, plus medroxyprogesterone acetate, 2.5 mg, in 1 tablet daily (n = 1380), or identical placebo (n = 1383).Main Outcome Measures: Lipoprotein(a) levels and CHD events (nonfatal myocardial infarction and CHD death).Results: Increased baseline Lp(a) levels were associated with subsequent CHD events among women in the placebo arm. After multivariate adjustment, women in the second, third, and fourth quartiles of baseline Lp(a) level had relative hazards (RHs) (compared with the first quartile) of 1.01 (95% confidence interval [CI], 0.64-1.59), 1.31 (95% CI, 0.85-2.04), and 1.54 (95% CI, 0.99-2.39), respectively, compared with women in the lowest quartile (P for trend = .03). Treatment with estrogen and progestin reduced mean (SD) Lp(a) levels significantly (-5.8 [15] mg/dL) (-0.20 [0.53] micromol/L) compared with placebo (0.3 [17] mg/dL) (0.01 [0.60] micromol/L) (P<.001). In a randomized subgroup comparison, women with low baseline Lp(a) levels had less benefit from estrogen and progestin than women with high Lp(a) levels; the RH for women assigned to estrogen and progestin compared with placebo were 1.49 (95% CI, 0.97-2.26) in the lowest quartile and 1.05 (95% CI, 0.67-1.65), 0.78 (0.52-1.18), and 0.85 (0.58-1.25) in the second, third, and fourth quartiles, respectively (P for interaction trend = .03).Conclusions: Our data suggest that Lp(a) is an independent risk factor for recurrent CHD in postmenopausal women and that treatment with estrogen and progestin lowers Lp(a) levels. Estrogen and progestin therapy appears to have a more favorable effect (relative to placebo) in women with high initial Lp(a) levels than in women with low levels. This apparent interaction needs confirmation in other trials. [ABSTRACT FROM AUTHOR]

Context: Recently, an algorithm based on the electrocardiogram (ECG) was reported to predict myocardial infarction (MI) in patients with left bundle-branch block (LBBB), but the clinical impact of this testing strategy is unknown.Objective: To determine the diagnostic test characteristics and clinical utility of this ECG algorithm for patients with suspected MI.Design: Retrospective cohort study to which an algorithm was applied, followed by decision analysis regarding thrombolysis made with or without the algorithm.Setting: University emergency department, 1994 through 1997.Patients: Eighty-three patients with LBBB who presented 103 times with symptoms suggestive of MI.Main Outcome Measures: Myocardial infarction determined by serial cardiac enzyme analyses and stroke-free survival.Results: Of 9 ECG findings assessed, none effectively distinguished the 30% of patients with MI from those with other diagnoses. The ECG algorithm indicated positive findings in only 3% of presentations and had a sensitivity of 10% (95% confidence interval, 2%-26%). The decision analysis showed that among 1000 patients with LBBB and chest pain, 929 would survive without major stroke if all received thrombolysis compared with 918 if the ECG algorithm was used as a screening test.Conclusions: The ECG is a poor predictor of MI in a community-based cohort of patients with LBBB and acute cardiopulmonary symptoms. Acute thrombolytic therapy should be considered for all patients with LBBB who have symptoms consistent with MI. [ABSTRACT FROM AUTHOR]