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Brandi J Witt

Publications and source records attributed to Brandi J Witt.

7 recordsLinked to original sources

Ventricular arrhythmias after acute myocardial infarction: a 20-year community study.

BACKGROUND: Although myocardial infarction (MI) severity is declining, the occurrence of ventricular arrhythmia (VA) after MI and its effect on outcome is unknown. This study was undertaken to examine the frequency and timing of VA and the effect of VA on mortality after MI. METHODS: Myocardial infarctions recorded between 1979 and 1998 were validated. Baseline characteristics, occurrence of VA, and survival were determined. Ventricular arrhythmias were categorized as primary ventricular fibrillation (VF), nonprimary VF, and ventricular tachycardia (VT). Logistic regression was used to analyze associations between VA and baseline characteristics. Temporal trends were assessed with the Mantel-Haenszel chi2. Survival was analyzed with the Kaplan-Meier method. Proportional hazards regression was used to examine the association between death and occurrence of VA. RESULTS: Among 2317 persons with incident MI, 7.5% experienced VA (3.6% nonprimary VF, 2.1% primary VF, 1.8% VT). Ventricular arrhythmia-associated factors were younger age, female sex, higher Killip class, ST elevation, and atrial fibrillation. Ventricular arrhythmias were associated with increased risk of death at 30 days. CONCLUSION: Ventricular arrhythmias after MI are relatively common, particularly among persons with more severe MI and no prior history of coronary disease. Over time, the incidence of VF declined, whereas VT did not change. Ventricular arrhythmia after MI was associated with a 6-fold increase in morality. Thus, identification of high-risk MI survivors and prevention of VA could markedly improve outcomes. Further studies are needed to determine the cause of the shift in distribution of VA subtype.

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Ischemic stroke after heart failure: a community-based study.

BACKGROUND: Although studies have examined the incidence of stroke in heart failure (HF), their findings are inconsistent and difficult to interpret because of heterogeneity in study design and population. Although HF remains a highly fatal disease, the excess mortality imparted from stroke is unknown. METHODS: A random sample of cases of HF from 1979 to 1999 was identified and validated according to Framingham criteria. Strokes were identified by screening medical diagnoses and subsequent physician validation. Stroke risk in HF was compared with the risk in the general population with standardized morbidity ratios. Associations between selected characteristics and stroke were examined using proportional hazards regression. RESULTS: The study cohort included 630 persons with incident HF. During a median of 4.3 years of follow-up, 102 (16%) experienced an ischemic stroke. Heart failure was associated with a 17.4-fold increased risk for stroke compared with the general population in the first 30 days after HF diagnosis and remained elevated during 5 years of follow-up. Older persons with prior stroke or diabetes were more likely to experience stroke after HF diagnosis. Persons with stroke after HF were 2.31 times more likely to die compared with persons without stroke. CONCLUSIONS: In the community, persons with HF have a large increase in the risk for ischemic stroke compared with the general population. Stroke results in a >2-fold increase in mortality. Thus, prevention of stroke has the potential to improve survival among patients with HF, particularly among the elderly and those with diabetes or prior stroke.

Age Factors↗

The incidence of stroke after myocardial infarction: a meta-analysis.

PURPOSE: While the risk of stroke after myocardial infarction (MI) is increased compared with the risk among those without MI, the magnitude of this risk remains unclear. Although numerous clinical trials have reported the incidence of stroke following MI, these are among selected populations. We reviewed cohort studies reporting the incidence of stroke after MI to better define the risk of ischemic stroke in an unselected population. METHODS: A computerized literature search (MEDLINE and PubMed) and manual review of reference lists of identified articles were conducted. Population-based studies published from 1978-2004 with at least 100 subjects that reported number or percent of ischemic strokes experienced by MI survivors were identified. Data were extracted using standardized forms, and study quality was assessed by 2 independent reviewers. Ischemic stroke rates were reported as number of events per 1000 MI with 95% confidence intervals (CI) calculated by Poisson distribution. A combined stroke rate was calculated for in-hospital, 30 days, and 1-year post-MI using weights of 1/variance. A random-effects model also was created to estimate in-hospital stroke rate. Variability in study designs and outcome definitions limit synthesis of available data. RESULTS: During hospitalization for the index MI, 11.1 ischemic strokes occurred per 1000 MI compared with 12.2 at 30 days and 21.4 at 1 year. Using a random-effects model, 14.5 strokes occurred per 1000 MI. Positive predictors of stroke after MI included: advanced age, diabetes, hypertension, history of prior stroke, anterior location of index MI, prior MI, atrial fibrillation, heart failure, and nonwhite race. CONCLUSIONS: The public health implications of stroke among MI survivors, as well as the large number of MI survivors, underscore the need to be aware of this devastating complication. Further research is needed to determine the optimal stroke prevention strategies for MI survivors.

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A community-based study of stroke incidence after myocardial infarction.

BACKGROUND: The rate of stroke after myocardial infarction (MI) remains unclear. OBJECTIVES: To examine the rate of stroke after incident MI; compare it with that observed in the population of Rochester, Minnesota; determine how the rate of stroke after MI has changed over time; and examine the impact of stroke on survival after incident MI. DESIGN: Community-based cohort. SETTING: Olmsted County, Minnesota. PARTICIPANTS: Persons with incident (first-ever) MI between 1979 and 1998. MEASUREMENTS: Ischemic or hemorrhagic stroke in hospitalized and nonhospitalized patients that was identified by screening of the medical record for stroke diagnostic codes and subsequent stroke confirmation by physician review of the recorded event. Medical record review was used to ascertain baseline characteristics and death. RESULTS: A total of 2160 persons with incident MI were hospitalized between 1979 and 1998 and followed for a median of 5.6 years (range, 0 to 22.2 years). The rate of stroke was 22.6 per 1000 person-months (95% CI, 16.3 to 30.6 per 1000 person-months) during the first 30 days after MI, corresponding to a 44-fold increase (standardized morbidity ratio, 44 [95% CI, 32 to 59]) risk for stroke in the population of Rochester, Minnesota. The risk for stroke remained 2 to 3 times higher than expected during the first 3 years after MI. Older age, previous stroke, and diabetes increased the risk for stroke, which did not decline over the study period. Strokes were associated with a large increase in the risk for death after MI (hazard ratio, 2.89 [CI, 2.44 to 3.43]). LIMITATIONS: Findings may not be generalizable to different populations. The authors measured outcomes by reviewing medical records. CONCLUSIONS: In the community, the risk for stroke is markedly increased after MI, particularly early after MI, compared with the expected risk in population without MI. Stroke is associated with a large increase in the risk for death after MI.

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Cardiac rehabilitation after myocardial infarction in the community.

OBJECTIVES: The aim of this study was to examine participation in cardiac rehabilitation after myocardial infarction (MI) by age and gender and the association of participation with survival. BACKGROUND: Lesser participation in cardiac rehabilitation has been reported for women and the elderly. METHODS: All incident MIs in Olmsted County were validated. Baseline characteristics and outcomes were ascertained from the medical record. Logistic regression examined the association between participation, age, and gender. Propensity scores were used to examine the association between participation and outcome. RESULTS: Among 1,821 persons with incident MI (58% men, 46% age >70 years), 55% participated in cardiac rehabilitation. Participants were more likely to be men, younger, and have fewer comorbidities (p < 0.01 for all comparisons). After adjustment, women were 55% less likely to participate than men (odds ratio [OR] 0.45, 95% confidence interval [CI] 0.34 to 0.60), and persons 70 years or older were 77% less likely to participate than persons younger than 60 (OR 0.23, 95% CI 0.16 to 0.33). Participants had a lower risk of death and recurrent MI at three years (p < 0.001 and p = 0.049, respectively). The survival benefit associated with participation was stronger in more recent years (relative risk [RR] for 1998 vs. 1982 0.28, 95% CI 0.18 to 0.43; RR for 1990 vs. 1982 0.41, 95% CI 0.33 to 0.52). CONCLUSIONS: Approximately half of the patients participated in cardiac rehabilitation after MI. Participation did not increase over time. Women and elderly persons were less likely to participate, independently of other characteristics. Participation in rehabilitation was independently associated with decreased mortality and recurrent MI, and its protective effect was stronger in more recent years.

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Sex differences in heart disease incidence and prevalence: implications for intervention.

Women present clinically with coronary disease later in life than men do, and given their increased life expectancy compared to men, represent an increasingly larger proportion of patients with coronary disease. Coronary disease in women results in a large human and financial burden to the healthcare system. Effective prevention measures should integrate the clinical and social features of coronary disease which are specific to women and should be anchored within a comprehensive understanding of the burden of coronary disease in women. While attention has been recently directed at coronary disease in women, there is relatively limited information on the incidence and prevalence of coronary disease in women and how it may have changed over time; few studies include sufficient numbers of women to draw appropriate inference. This paper reviews the epidemiology of coronary disease in women and discusses the implications for intervention.

Adult↗