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BACKGROUND: Stress echocardiographic studies are useful, but the evaluation of wall motion is sometimes suboptimal. The recently developed technique of power motion imaging can enhance mobile tissue definition. HYPOTHESIS: The study was undertaken to determine whether power motion imaging improves endocardial definition during tachycardia compared with conventional two-dimensional (2-D) imaging. METHODS: Twenty pigs were studied during pacing rates of 100, 120, and 150 beats/min. We compared power motion imaging with standard 2-D imaging using systolic thickening visualization (STV) scores (3 = excellent definition of systolic thickening approximately 0 = total lack of visualization of systolic thickening) at each heart rate. We calculated the sum of the scores of 22 left ventricular segments as the overall STV score, and also calculated the sum of the scores in 10 parasternal segments and 12 apical segments separately. RESULTS: The overall STV scores in both imaging methods were similar at 100 beats/min, but scores for power motion imaging were significantly higher than those of usual 2-D imaging at 120 and 150 beats/min. Using power motion imaging, the overall STV scores were similar as heart rate was increased; however, while using standard 2-D imaging, STV scores were significantly decreased as heart rate was increased. Findings were analyzed separately by parasternal and apical images. Especially in the parasternal images, the scores were significantly increased as heart rate was increased using power motion imaging. CONCLUSIONS: We conclude that power motion imaging improves the detection of endocardial border in stress condition with tachycardia, and thus this modality is useful for stress echocardiography.

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Left ventricular outflow tract stroke distance (SD) can be measured using pulsed-wave Doppler echocardiography, and is independent of body size. Moreover, persons with structurally normal hearts (heart rate < 55 beats/min) had SD > 0.18 m, and those with a heart rate > 95 beats/min had SD < 0.22 m; outside of these parameters, low- and high-output states are likely to exist, and suspicion of these can be confirmed by calculation of minute distance (normal range 9.7 to 20.5 m/min).

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The clinician evaluating a woman with symptoms potentially indicative of coronary heart disease faces the challenge of choosing the appropriate diagnostic test. The use of noninvasive testing in women has been controversial due to a perception of diminished accuracy, limited female representation, and technical limitations that compromise efficacy. Recent meta-analyses and large observational series report marked improvements in accuracy for women undergoing exercise treadmill, echocardiography, and nuclear testing. Electron beam computed tomography is a relatively new technique, and the body of evidence is still developing. An adequate body of evidence supports the use of noninvasive testing for intermediate risk, symptomatic women and may result in improved diagnostic and therapeutic decision making.

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Apolipoprotein L is a newly recognized component of human plasma lipoproteins. Mainly associated with apoA-I-containing lipoproteins, it is a marker of distinct HDL subpopulations. In an effort to gain inference as to its as yet unknown function, we studied biological determinants of apoL levels in human plasma. The distribution of apoL in normal subjects is asymmetric, with marked skewing toward higher values. No difference was found in apoL concentrations between males and females, but we observed an elevation of apoL in primary hypercholesterolemia (10.1 vs. 8.5 microgram/mL in control), in endogenous hypertriglyceridemia (13.8 microgram/mL, P < 0.001), combined hyperlipidemia phenotype (18.7 g/mL, P < 0.0001), and in patients with type II diabetes (16.2 microgram/mL, P < 0.02) who were hyperlipidemic. Significant positive correlations were observed between apoL and the log of plasma triglycerides in normolipidemia (0.446, P < 0.0001), endogenous hypertriglyceridemia (0.435, P < 0.01), primary hypercholesterolemia (0.66, P < 0.02), combined hyperlipidemia (0.396, P < 0.04), hypo-alphalipoproteinemia (0.701, P < 0.005), and type II diabetes with hyperlipidemia (0.602, P < 0. 01). Apolipoprotein L levels were also correlated with total cholesterol in normolipidemia (0.257, P < 0.004), endogenous hypertriglyceridemia (0.446, P = 0.001), and non-insulin-dependent diabetes mellitus (NIDDM) (0.548, P < 0.02). No significant correlation was found between apoL and body mass index, age, sex, HDL-cholesterol or fasting glucose and glycohemoglobin levels. ApoL levels in plasma of patients with primary cholesteryl ester transfer protein deficiency significantly increased (7.1 +/- 0.5 vs. 5.47 +/- 0.27, P < 0.006).

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OBJECTIVES: We sought to test the hypothesis that C-reactive protein, a marker of inflammation, would correlate positively with coronary calcium, a marker of atherosclerosis, in postmenopausal women. BACKGROUND: High sensitivity testing for C-reactive protein (hsCRP) has recently been shown in large population studies to predict cardiac events in asymptomatic postmenopausal women. Coronary calcification determined by electron beam computerized tomography (EBCT) has also been suggested to be predictive of cardiac events in women. METHODS: We performed hsCRP testing and determined calcium scores by EBCT in 172 asymptomatic postmenopausal women (mean age: 64.5 +/- 7.9 years) at risk for cardiac disease. Risk factors were determined by history, physical, electrocardiogram, exercise testing, and lipoprotein profiles. RESULTS: Calcium scores ranged from 0 to 2,618. For analysis, calcium scores were divided into three groups; none (0 to 10), minimal (>10 to 50), and significant (>50). Overall, there was no significant positive relationship between hsCRP level and calcium score. Specifically, the hsCRP levels (mg/dl) were 0.24 +/- 0.43, 0.33 +/- 0.47 and 0.17 +/- 0.32 (medians 0.11, 0.15, and 0.06) for women with none, minimal, and significant coronary calcification, respectively. In subgroup analysis, a similar lack of positive association was observed after stratification by smoking status and by hormone replacement therapy use, two factors known to increase hsCRP. CONCLUSIONS: In contrast to our a priori hypothesis, we found no evidence of a positive association between hsCRP and calcium score by EBCT. These data thus raise the possibility that hsCRP and EBCT calcium score reflect different pathologic processes, an issue with implications for coronary artery disease screening.

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CONTEXT: One of 2 women in the United States dies of heart disease or stroke, yet women are underdiagnosed and undertreated for these diseases and their risk factors. Informed decisions to prevent heart disease and stroke depend on awareness of risk factors and knowledge of behaviors to prevent or detect these diseases. OBJECTIVE: Assess (1) knowledge of risks of heart disease and stroke and (2) perceptions of heart disease and its prevention among women in the United States. DESIGN AND SETTING: Telephone survey conducted in 1997 of US households, including an oversample of African American and Hispanic women. PARTICIPANTS: One thousand respondents 25 years or older; 65.8% white, 13.0% African American, and 12.6% Hispanic. MAIN OUTCOME MEASURES: Knowledge of heart disease and stroke risks, perceptions of heart disease, and knowledge of symptoms and preventive measures. RESULTS: Only 8% of the respondents identified heart disease and stroke as their greatest health concerns; less than 33% identified heart disease as the leading cause of death. More women aged 25 to 44 years identified breast cancer as the leading cause of death than women 65 years or older. Women aged 25 to 44 years indicated they were not well informed about heart disease and stroke. Although 90% of the women reported that they would like to discuss heart disease or risk reduction with their physicians, more than 70% reported that they had not. CONCLUSIONS: Most women do not perceive that heart disease is a substantial health concern and report that they are not well informed about their risk. Age influenced knowledge to a greater extent than ethnicity. Programs directed at young women that address the effects of lifestyle behaviors on long-term health are needed. Better communication between physicians and patients is also warranted.

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BACKGROUND: The ability to predict the rate of hemodynamic progression in an individual patient with valvular aortic stenosis has been elusive. The purpose of the present study was to evaluate whether the rate of change in aortic valve area (AVA) measured during the ejection phase of a cardiac cycle predicts the rate of hemodynamic progression in patients with asymptomatic aortic stenosis. METHODS AND RESULTS: In 84 adults with initially asymptomatic aortic stenosis and a baseline AVA of > or =0.9 cm(2), annual echocardiographic data were obtained prospectively (mean follow-up 2.8+/-1.3 years). With the initial echocardiogram, the ratio of AVA measured at mid-acceleration and mid-deceleration to the AVA at peak velocity was calculated. The primary outcome variable was the annual rate of change in AVA (rate of progression), with rate of progression classified as rapid (a reduction in AVA of > or =0.2 cm(2)/y) or slow (<0.2 cm(2)/y). Rapid progression was significantly associated with an AVA ratio of > or =1.25 (P=0.004, risk ratio 3.1, 95% CI 1.2 to 7.9). The sensitivity, specificity, and positive predictive value of AVA ratio of > or =1.25 for the prediction o rapid progression of valvar aortic stenosis was 64%, 72%, and 80% respectively. The decrease in ejection fraction measured from the initial to final echocardiogram was small but greater for patients with an AVA ratio of > or =1.25 (-4+/-7% versus +2+/-7%, P<0.001). CONCLUSIONS: A flow-dependent change in AVA can be measured during a routine transthoracic echocardiographic study. The rate of change in AVA is an additional measure of disease severity and may be used to predict an individual's risk for subsequent rapid disease progression.

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BACKGROUND: Short-term estrogen administration improves vasodilation and has been shown to improve exercise capacity. However, it is unknown whether long-term estrogen replacement therapy is associated with improved exercise capacity in postmenopausal women without known coronary artery disease. METHODS AND RESULTS: We studied 248 postmenopausal women without known coronary artery disease (mean age 63.5 years); 158 (64%) were current or past hormone replacement therapy (HRT) users and 108 (44%) were current users of HRT. Attributes potentially affecting exercise capacity and cardiac risk factors were carefully measured. These included duration of estrogen replacement therapy, all variables in the Framingham risk index, physical activity level, body mass index, waist-to-hip ratio, presence of osteoporosis, and family history of heart disease. We measured maximal oxygen uptake (MVO (2)) and anaerobic threshold as objective markers of exercise capacity. The relation between exercise capacity and use of HRT was analyzed with the use of logistic regression, controlling for confounding variables. We found that fitness, as measured by MVO (2) and anaerobic threshold, was significantly greater in women who had used HRT currently or in the past compared with women who had never used HRT. This difference in fitness was not confounded by age or physical activity level. CONCLUSIONS: Estrogen replacement therapy is associated with increased exercise capacity as measured by MVO (2) and anaerobic threshold in postmenopausal women without coronary artery disease. This finding is consistent with the beneficial effect of short-term estrogen administration on improved endothelium-dependent and endothelium-independent vasodilation.

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OBJECTIVES: This study sought to determine the relationship of lipoprotein(a) (Lp(a)) and other cardiac risk factors to coronary atherosclerosis as measured by calcification of coronary arteries in asymptomatic postmenopausal women. BACKGROUND: Lipoprotein(a) is considered a risk factor for coronary heart disease. Coronary calcium deposition is believed to be a useful noninvasive marker of coronary atherosclerosis in women. However, to our knowledge, there are no reports of the relationship of Lp(a) to coronary calcium in postmenopausal women. METHODS: In 178 asymptomatic postmenopausal women (64 +/- 8 years), we measured Lp(a) and other cardiac risk factors: age, hypertension, diabetes, low-density lipoprotein cholesterol, smoking status, body mass index, physical activity level and duration of hormone replacement therapy. Electron-beam computed tomography was done to measure coronary calcium (calcium score). We analyzed the relationship between calcium score and cardiac risk factors using multivariate analysis. RESULTS: Although calcium score correlated with traditional risk factors of age, diabetes, hypertension and smoking, it did not correlate with Lp(a) in the asymptomatic postmenopausal women. Similar multivariate analyses were done in the subjects age >60 years and in the subjects with significant coronary calcium deposit (calcium score > or =50). These analyses also have failed to show an association of levels of Lp(a) with coronary calcium deposits. CONCLUSIONS: We conclude that in asymptomatic postmenopausal women, Lp(a) levels do not correlate with coronary atherosclerosis as measured by coronary calcium deposits.

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Marked reductions in cardiovascular mortality have been reported over the last 2 decades as a result of therapeutic advances in ischemic heart disease. Despite medical advances, case fatality rates are higher for women than men. A critical step toward improving outcomes is early diagnosis of coronary artery disease by noninvasive evaluation. The use of noninvasive testing in women has been controversial because of a perception of diminished accuracy, limited female representation, and compromise of efficacy of testing because of technical limitations (eg, thallium-201 breast artifact). Recent meta analysis and large observational series report marked improvements in the accuracy of results for women undergoing exercise treadmill, echocardiography, and nuclear testing. Exercise treadmill testing has an improved accuracy when multiple risk parameters (eg, ST deviation, chest pain, exercise time) are included in the test interpretation. For women, a low-risk Duke treadmill score is associated with a 97% 5-year survival, with 80% of these patients having no obstructive disease. Multivessel disease (70%) is common for those with a high-risk treadmill score with a 5-year survival of 90%. The diagnostic accuracy of electron beam computed tomography reveals a sensitivity and specificity of 88% and 49%. For exercise echocardiography, test diagnostic sensitivity and specificity are 86% and 79%. For nuclear imaging, 3-year cardiac survival ranged from 99% to 85% for 0 to 3 vascular territories with perfusion abnormalities. A sufficient body of evidence supports the use of noninvasive testing for intermediate-risk, symptomatic women. Diagnostic certainty may be effectively guided by the evaluation of global and regional wall motion, eg, with echocardiography. Risk assessment may be more precise with the evaluation of myocardial perfusion, eg, with stress nuclear imaging. With the use of updated evidence, informed test selection for women may result in improved diagnostic and therapeutic decision-making, with the use of available noninvasive testing modalities.

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Noninvasive diagnostic testing of coronary artery disease (CAD) is widely recognized as an area that is less studied and less accurate with regard to women than to men. Accurate and safe diagnostic testing constitutes the crucial link between early detection and optimal management of CAD. Many noninvasive diagnostic modalities are available to the clinician, including traditional electrocardiography, the relatively novel imaging of echocardiography, the emerging nuclear perfusion technology of electron beam computed tomography, exercise testing, and pharmacologic testing. The most accurate and cost-effective diagnostic method for patients depends on the patients' pretest likelihood of the disease as determined by factors such as sex, age, and cardiovascular risk factors. Noninvasive tests are most useful in the diagnosis of CAD in patients with intermediate pretest likelihood of CAD. Patients with low pretest likelihood of CAD with normal electrocardiograms may benefit from noninvasive tests or a watchful waiting strategy. Patients with a high pretest likelihood of CAD may benefit greatly from direct referral to coronary angiography. Among the noninvasive diagnostic methods, exercise electrocardiography is the most studied and least accurate with regard to women patients. Electrocardiography improves in accuracy when combined with imaging techniques such as echocardiography or nuclear single photon emission computed tomography. Combining data from all studies has shown that exercise echocardiography yields the highest diagnostic accuracy in women among all of the exercise stress tests. Patients who are unable to achieve maximal exercise capacity may undergo pharmacologic testing using dipyridamole or adenosine radionuclide perfusion or dobutamine echocardiography. Recent development of electron beam computed tomography accurately detects coronary artery calcium but has not been validated yet as a standard diagnostic test for CAD.

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BACKGROUND: The optimal strategy for the diagnosis of coronary artery disease (CAD) in women is not well defined. We compared the cost-effectiveness of several strategies for diagnosing CAD in women with chest pain. METHODS: We performed decision and cost-effectiveness analyses with simulations of 55-year-old ambulatory women with chest pain. With a Markov model, simulations of patients underwent exercise electrocardiography, exercise testing with thallium scintigraphy, exercise echocardiography, angiography, or no workup. RESULTS: Diagnosis with angiography cost less than $17, 000 per quality-adjusted life-year compared with exercise echocardiography if the patient had definite angina and less than $76,000 per life-year if she had probable angina. If she had nonspecific chest pain, diagnosis with exercise echocardiography increased life-years compared with no testing. CONCLUSIONS: Cost-effectiveness of first-line diagnostic strategy for diagnosis of CAD in women varies mostly according to pretest probability of CAD. Diagnosis of coronary artery disease with angiography is cost-effective in 55-year-old women with definite angina. In 55-year-old women with probable angina, diagnosis with angiography would increase quality-adjusted life-years but significantly increase costs. Use of exercise echocardiography as a first-line diagnosis for CAD is cost effective in 55-year-old women with probable angina and nonspecific chest pain.

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