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We retrospectively studied the outcomes of patients with acute myocardial infarction who were treated with either direct angioplasty or thrombolytics followed by angioplasty. Two patient cohorts were analyzed: a previously reported (in regard to short-term follow-up) group of 371 patients who now have long-term follow-up (mean, 3.4 years) of survival and event-free survival and a second group of 202 patients who have been treated since publication of our initial data. Both 1-year and 2-year survival were significantly better (p = 0.01 and 0.02, respectively) in the group that was treated with thrombolytics first. Event-free survival (i.e., no myocardial infarction, coronary artery bypass graft surgery, repeat angioplasty) was better overall (p < 0.01) for the group that was treated with thrombolytics first. The more recently treated group of patients also showed benefit in regard to both survival (p = 0.002) and event-free survival (p < 0.01) over a short-term follow-up period (mean, 39 weeks) for patients who were treated initially with thrombolytics as compared with those who were treated with direct angioplasty. Although the initial cohort was very similar to the treatment groups except for age (mean age for the direct angioplasty group was 62 +/- 12 years vs 57 +/- 11 years for thrombolytics first group, (p = 0.0002), several differences existed in the more recent treatment groups. The patients who were more recently treated with direct angioplasty were older, had lower mean ejection fraction, had more extensive coronary artery disease, and were more likely to have had prior coronary artery bypass grafting.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Background

Data are limited about race-and sex-associated differences in prognostically important ECG measures of regional repolarization.

Methods and results

The normal reference group from the Atherosclerosis Risk in Communities (ARIC) study included 8,676 white and African-American men and women aged 40–65 years. Exclusion criteria included cardiovascular disease, hypertension, diabetes and major ECG abnormalities. Notable sex differences (p < 0.001) were observed in the upper 98% limits for rate-adjusted QTend (QTea) which was 435 ms in white and African-American men and 445 ms in white and African-American women, and for left ventricular epicardial repolarization time (RTepi) which was 345 ms in white and African-American men and 465 ms in white and African-American women. These sex differences reflect earlier onset and end of repolarization in men than in women. Upper normal limits for STJ amplitude in V2–V3 were 100 μV in white and African-American women, 150 μV in white men and 200 μV in African-American men (p < 0.001 for sex differences), and for other chest leads, aVL and aVF 50 μV in white women, 100 μV in African-American women, 100 μV in white men and 150 μV in African-American men (p < 0.001 for sex and race differences).

Conclusions

Shorter QTea and RTepi in men than in women reflect earlier onset and end of repolarization in men. STJ amplitudes in African-American men were higher than in other subgroups by race and sex. These sex and race differences need to be considered in clinical and epidemiological applications of normal standards.  相似文献   
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Heart failure causes significant morbidity and mortality. Distinguishing risk factors for incident heart failure can help identify at-risk individuals. Orthostatic hypotension may be a risk factor for incident heart failure; however, this association has not been fully explored, especially in nonwhite populations. The Atherosclerosis Risk in Communities Study included 12363 adults free of prevalent heart failure with baseline orthostatic measurements. Orthostatic hypotension was defined as a decrease of systolic blood pressure ≥20 mmHg or diastolic blood pressure ≥10 mmHg with position change from supine to standing. Incident heart failure was identified from hospitalization or death certificate disease codes. Over 17.5 years of follow-up, orthostatic hypotension was associated with incident heart failure with multivariable adjustment (hazard ratio: 1.54 [95% CI: 1.30-1.82]). This association was similar across race and sex groups. A stronger association was identified in younger individuals ≤55 years old (hazard ratio: 1.90 [95% CI: 1.41-2.55]) than in older individuals >55 years old (hazard ratio: 1.37 [95% CI: 1.12-1.69]; interaction P=0.034). The association between orthostatic hypotension and incident heart failure persisted with exclusion of those with diabetes mellitus, coronary heart disease, and those on antihypertensives or psychiatric or Parkinson disease medications. However, exclusion of those with hypertension somewhat attenuated the association (hazard ratio: 1.34 [95% CI: 1.00-1.80]). We identified orthostatic hypotension as a predictor of incident heart failure among middle-aged individuals, particularly those 45 to 55 years of age. This association may be partially mediated through hypertension. Orthostatic measures may enhance risk stratification for future heart failure development.  相似文献   
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