Showing papers by "Nemat O. Borhani published in 1996"

Final Outcome Results of the Multicenter Isradipine Diuretic Atherosclerosis Study (MIDAS): A Randomized Controlled Trial

Abstract: Objective —To compare the rate of progression of mean maximum intimal-medial thickness (IMT) in carotid arteries, using quantitative B-mode ultrasound imaging, during antihypertensive therapy with isradipine vs hydrochlorothiazide Design —Randomized, double-blind, positive-controlled trial Setting —Nine medical center clinics Population —A total of 883 patients with baseline mean ±SD systolic and diastolic blood pressure (SBP and DBP, respectively) of 1497±166 and 965±51 mm Hg, age of 585±85 years, and maximum IMT of 117±020 mm Interventions —Twice daily doses of isradipine (25-50 mg) or hydrochlorothiazide (125-25 mg) Main Outcome Measure (Primary End Point) —Rate of progression of mean maximum IMT in 12 carotid focal points over 3 years Results —There was no difference in the rate of progression of mean maximum IMT between isradipine and hydrochlorothiazide over 3 years (P=68) There was a higher incidence of major vascular events (eg, myocardial infarction, stroke, congestive heart failure, angina, and sudden death) in isradipine (n=25; 565%) vs hydrochlorothiazide (n=14; 317%) (P=07), and a significant increase in nonmajor vascular events and procedures (eg, transient ischemic attack, dysrhythmia, aortic valve replacement, and femoral popliteal bypass graft) in isradipine (n=40; 905%) vs hydrochlorothiazide (n=23; 522%) (P=02) At 6 months, mean DBP decreased by 130 mm Hg in both groups, and mean SBP decreased by 195 mm Hg in hydrochlorothiazide and 160 mm Hg in isradipine (P=002); the difference in SBP between the 2 groups persisted throughout the study but did not explain the increased incidence of vascular events in patients treated with isradipine Conclusion —The rate of progression of mean maximum IMT in carotid arteries, the surrogate end point in this study, did not differ between the 2 treatment groups The increased incidence of vascular events in patients receiving isradipine compared with hydrochlorothiazide is of concern and should be studied further

Thickening of the carotid wall. A marker for atherosclerosis in the elderly? Cardiovascular Health Study Collaborative Research Group.

Abstract: Background and Purpose We investigated the relationships between prevalent coronary heart disease (CHD), clinically manifest atherosclerotic disease (ASD), and major established risk factors for atherosclerosis and intima-media thickness (IMT) in the common carotid arteries (CCA) and internal carotid arteries (ICA) separately and in combination in older adults. We wished to determine whether a noninvasive measurement can serve as an indicator of clinically manifest atherosclerotic disease and to determine which of the two variables, CCA IMT or ICA IMT, is a better correlate. Methods IMT of the CCA and ICA was measured with duplex ultrasound in 5117 of 5201 individuals enrolled in the Cardiovascular Health Study, a study of the risk factors and the natural history of cardiovascular disease in adults aged 65 years or more. Histories of CHD, peripheral arterial disease, and cerebrovascular disease were obtained during baseline examination. Risk factors included cholesterol levels, cigarette smoking, elevated...

Compensatory increase in common carotid artery diameter : Relation to blood pressure and artery intima-media thickness in older adults

Abstract: Background and Purpose Common carotid artery (CCA) diameter is thought to increase as a consequence of hypertension and may increase as the thickness of the arterial wall increases. The purpose of this study was to determine CCA dimensions and correlate them with clinical features. Methods We performed a cross-sectional, community-based study of adults 65 years of age and older, measuring inner and outer diameter of the CCA in vivo with carotid sonography. Findings were correlated against risk factors for atherosclerosis, CCA intima-media thickness (IMT), and echocardiographically determined left ventricular (LV) mass. Results Independent variables showing strong positive associations with outer and inner CCA diameter included age, male sex, height, weight, and systolic blood pressure. As an independent variable, LV mass (r=.40 and r=.37, respectively; P<.00001) had a strong positive relation to inner and outer CCA diameters. The relationship between diameter and IMT was different. In a model that control...

Utility of New Electrocardiographic Models for Left Ventricular Mass in Older Adults

Abstract: Several multivariate statistical models have recently been introduced for estimation of left ventricular mass from standard 12-lead electrocardiographic measurements. The validity of these algorithms has not been adequately evaluated. The objective of this investigation was to compare the associations between echocardiographic and electrocardiographic left ventricular mass values with clinical and subclinical indexes of coronary heart disease. The evaluation was performed with participants of the Cardiovascular Health Study, a population-based sample of 5201 men and women aged 65 years and older. Echocardiographic M-mode measurements of left ventricular mass were performed from videotape recordings with the use of a strictly standardized protocol. Electrocardiographic algorithms of the Novacode program and new algorithms derived from the Cardiovascular Health Study population were used for left ventricular mass prediction. Echocardiographic and electrocardiographic determinations of left ventricular mass were technically successful in 3410 (65.6%) and 5013 (96.4%) participants, respectively. The Novacode model overestimated echocardiographic left ventricular mass. Compared with the Novacode model, the new Cardiovascular Health Study electrocardiographic model, which includes adjustment for body weight, eliminated left ventricular mass prediction bias and improved the correlation between echocardiographic and electrocardiographic left ventricular mass from .33 to .54 in women and from .46 to .51 in men. Echocardiographic and electrocardiographic models both demonstrated similar and about equally strong associations with overt and subclinical disease and with risk factors for left ventricular hypertrophy. These observations demonstrate the potential utility of electrocardiographic models for left ventricular mass estimation.

Classification Accuracy of Electrocardiographic Criteria for Left Ventricular Hypertrophy in Normal Weight and Overweight Older Adults

Abstract: Background: We evaluated classification accuracy of ECG criteria at varying levels of left ventricular hypertrophy (LVH) severity according to echocardiographically measured left ventricular mass (LVM) adjusted to body size. Methods: The test population was derived from the Cardiovascular Health Study (CHS), a population-based sample of 5201 men and women aged 65 and older, and consisted of 1844 women and 1119 men with adequate quality ECGs and echocardiograms for LVM determination. The criteria evaluated were Sokolow-Lyon, Cornell voltage, Cornell product, Framingham modification of the Cornell voltage, and the left ventricular mass index (LVMI) of the Novacode ECG program. Results: With LVH thresholds at upper 95% normal limit for weight adjusted LVM for the CHS population and ECG thresholds adjusted for 95% specificity in normal weight and overweight subgroups, the sensitivity of ECG criteria for LVH was relatively low. It was highest (40.8%) for the Novacode LVMI in normal weight men and for the Framingham criteria (30.9%) in normal weight women, but it deteriorated for both of these criteria in the presence of obesity. The overall performance of the Cornell product and Cornell voltage criteria was least influenced by obesity. The Framingham adjustment for the Cornell voltage criteria for obesity substantially reduced their sensitivity. Conclusion: The choice of echocardiographic standard, LVH severity level and overweight in the test groups have a strong influence on ECG evaluation results.