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J S Gottdiener

Publications and source records attributed to J S Gottdiener.

At least 19 recordsLinked to original sources
PubMed2001

Usefulness of T-axis deviation as an independent risk indicator for incident cardiac events in older men and women free from coronary heart disease (the Cardiovascular Health Study).

T-axis shift has been reported to be an indicator of increased mortality risk. We evaluated the association of spatial T-axis deviation with incident coronary heart disease (CHD) events in older men and women free from clinically overt CHD. Spatial T-axis deviation was measured from the standard 12-lead electrocardiogram of a subgroup of 4,173 subjects considered free of CHD at baseline in the Cardiovascular Health Study, a prospective cohort study of risk factors for CHD and stroke in older men and women. Cox regression analysis was used to evaluate the association of altered repolarization with the risk of incident CHD events. The prevalence of marked T-axis deviation (> or =45 degrees ) was 12%. During the median follow-up of 7.4 years, there were 161 CHD deaths, 743 deaths from all causes, and 679 incident CHD events. Adjusting for demographic and clinical risk factors, including other electrocardiographic abnormalities, there was a nearly twofold excess risk of CHD death, and approximately a 50% excess risk of incident CHD and all-cause mortality for those with marked T-axis deviation. From other electrocardiographic abnormalities, only QT prolongation was associated with excess risk for incident CHD comparable to that for abnormal T-axis deviation. These results suggest that T-axis deviation is an easily quantified marker for subclinical disease and an independent indicator for the risk of incident CHD events in older men and women free of CHD.

Aged↗
PubMed2001

Ventricular and myocardial function following treatment of hypertension.

This study assesses and evaluates left ventricular (LV) contractile function after treatment of hypertension, with an emphasis on LV midwall mechanics. Although prior studies have assessed cardiac function after hypertension treatment, none has performed an analysis of LV midwall mechanics. The Veterans Affairs Study of monotherapy in hypertension was a study large enough to permit analysis of midwall mechanics across a wide spectrum of mass changes accompanying hypertension treatment. LV chamber function was assessed by computing fractional shortening at the endocardial surface; LV midwall shortening was used to define myocardial function. Both shortening indexes were related to end-systolic circumferential stress in the entire population by partitioning values of mass and relative wall thickness changes. Two hundred sixty-eight patients were studied at baseline and again after a 1- or 2-year period. In the entire group, there was no significant change in circumferential shortening either at the endocardium (38 +/- 8% at baseline vs 37 +/- 7% at follow up, p = 0.29) or in shortening at the midwall (20 +/- 3% vs 20 +/- 3%, p = 0.53). However, 83 patients had a reduction in relative wall thickness and an increase in midwall shortening. The change in midwall shortening was significantly related to changes in relative wall thickness (r = -0.53, p = 0.0001). Thus, reductions in LV mass associated with antihypertensive therapy are generally not accompanied by a decrement in LV chamber or myocardial function. Improvement in midwall shortening is more closely related to normalization of LV geometry than to reduction in LV mass.

Analysis of Variance↗
PubMed2001

Predictive value of systolic and diastolic function for incident congestive heart failure in the elderly: the cardiovascular health study.

OBJECTIVES: We sought to assess the ability of echocardiographic indices of systolic and diastolic function to predict incident congestive heart failure (CHF). BACKGROUND: Noninvasive indices of subclinical systolic and/or diastolic dysfunction that can be used to identify patients in a transition phase between normal cardiac function and clinical CHF would be valuable. Though midwall shortening and Doppler mitral inflow patterns are seemingly well suited to predict subsequent CHF, the predictive value of these indices has not been investigated. METHODS: We studied 2,671 participants in the Cardiovascular Health Study who were free of coronary heart disease, CHF or atrial fibrillation. Clinical and quantitative echocardiographic data were obtained in all participants. RESULTS: At a mean follow-up of 5.2 years (range 0 to 6 years), 170 participants (6.4% of the cohort) developed CHF. Although 96% of these participants had normal or borderline ejection fraction (EF) at baseline, only 57% had normal or borderline EF at the time of hospitalization. In multivariate modeling, fractional shortening at the endocardium (relative risk [RR] 1.85 per 10-unit decrease, confidence interval [CI] 1.27 to 2.39), fractional shortening at the midwall (RR 1.29 per five-unit decrease, 95% CI 1.11-1.51) and peak Doppler peak E (RR 1.15 for each 0.1 M/s increment; CI 1.02 to 1.21) independently predicted incident CHF. Both high and low Doppler E/A ratios were predictive of incident CHF. CONCLUSIONS: Roughly half the occurrences of CHF in this population are associated with normal or borderline EF. Echocardiographic findings suggestive of subclinical contractile dysfunction and diastolic filling abnormalities are both predictive of subsequent CHF. The standard (FSendo) and refined (FSmw) parameters of systolic function performed similarly in this regard, though subjects with left ventricular hypertrophy and depressed FSmw are at particularly high risk for subsequent CHF.

Age Factors↗
PubMed2001

Importance of heart failure with preserved systolic function in patients > or = 65 years of age. CHS Research Group. Cardiovascular Health Study.

Although congestive heart failure (CHF) is a common syndrome among the elderly, there is a relative paucity of population-based data, particularly regarding CHF with normal systolic left ventricular function. A total of 4,842 independent living, community-dwelling subjects aged 66 to 103 years received questionnaires on medical history, family history, personal habits, physical activity, and socioeconomic status, confirmation of pre-existing cardiovascular and cerebrovascular disease, anthropometric measurements, casual seated random-zero blood pressure, forced vital capacity and expiratory volume in 1 second, 12-lead supine electrocardiogram, fasting glucose, creatinine, plasma lipids, carotid artery wall thickness by ultrasonography, and echocardiography-Doppler examinations. Participants with at least 1 confirmed episode of CHF by Cardiovascular Health Study criteria were considered prevalent for CHF. The prevalence of CHF was 8.8% and was associated with increased age, particularly for women, in whom it increased more than twofold from age 65 to 69 years (6.6%) to age > or = 85 years (14%). In multivariate analysis, subjects with CHF were more likely to be older (odds ratio [OR] 1.2 for 5-year difference, men OR 1.1), and more often had a history of myocardial infarction (OR 7.3), atrial fibrillation (OR 3.0), diabetes mellitus (OR 2.1), renal dysfunction (OR 2.0 for creatinine < or = 1.5 mg/ dl), and chronic pulmonary disease (OR 1.8; women only). The echocardiographic correlates of CHF were increased left atrial and ventricular dimensions. Importantly, 55% of subjects with CHF had normal left ventricular systolic function and 80% had either normal or only mildly reduced systolic function. Among subjects with CHF, women had normal systolic function more frequently than men (67% vs 42%; p < 0.001). Thus, CHF is common among community-dwelling elderly. It increases with age and is usually associated with normal systolic LV function, particularly among women. The finding that a large proportion of elderly with CHF have preserved LV systolic function is important because there is a paucity of data to guide management in this dominant subset.

Aged↗
PubMed2001

Effects of mental stress on coronary epicardial vasomotion and flow velocity in coronary artery disease: relationship with hemodynamic stress responses.

OBJECTIVES: This study examines the prevalence and hemodynamic determinants of mental stress-induced coronary vasoconstriction in patients undergoing diagnostic coronary angiography. BACKGROUND: Decreased myocardial supply is involved in myocardial ischemia triggered by mental stress, but the determinants of stress-induced coronary constriction and flow velocity responses are not well understood. METHODS: Coronary vasomotion was assessed in 76 patients (average age 59.9 +/- 10.4 years; eight women). Coronary flow velocity responses were assessed in 20 of the 76 patients using intracoronary Doppler flow. Repeated angiograms were obtained after a baseline control period, a 3-min mental arithmetic task and administration of 200 microg intracoronary nitroglycerin. Arterial blood pressure (BP) and heart rate assessments were made throughout the procedure. RESULTS: Mental stress resulted in significant BP and heart rate increases (p < 0.001). Coronary constriction (>0.15 mm) was observed in 11 of 59 patients with coronary artery disease (CAD) (18.6%). Higher mental stress pressor responses were associated with more constriction in diseased segments (rdeltaSBP = -0.26, rdeltaDBP = -0.30, rdeltaMAP = -0.29; p's < 0.05) but not with responses in nonstenotic segments. The overall constriction of diseased segments was not significant (p > 0.10), whereas a small but significant constriction occurred in nonstenotic segments (p = 0.04). Coronary flow velocity increased in patients without CAD (32.2%; p = 0.008), but not in patients with CAD (6.4%; p = ns). Cardiovascular risk factors were not predictive of stress-induced vasomotion in patients with CAD. CONCLUSIONS: Coronary vasoconstriction in angiographically diseased arteries varies with hemodynamic responses to mental arousal. Coronary flow responses are attenuated in CAD patients. Thus, combined increases in cardiac demand and concomitant reduced myocardial blood supply may contribute to myocardial ischemia with mental stress.

Aged↗
PubMed2001

Specificity of Doppler echocardiography for the assessment of changes in valvular regurgitation: comparison of side-by-side versus serial interpretation.

OBJECTIVES: We sought to determine the specificity of two different methods for assessing change in aortic (AR), mitral (MR) and tricuspid (TR) valvular regurgitation. BACKGROUND: Echocardiographic imaging with Doppler is the standard noninvasive diagnostic tool for assessing valvular structure and function. Change can be assessed using either independent evaluations (serial) or using a side-by-side comparison. METHODS: Subjects were from the placebo arm of a randomized, double-blind, clinical trial. Three echocardiograms over 10 months were performed. An initial and three-month echocardiogram were read as independent groups, blinded to all parameters except sequence. The initial and 10-month echocardiograms were read side-by-side, blinded to all parameters including sequence. RESULTS: Two hundred nineteen predominantly healthy, obese, white, middle-aged women had initial and three-month echocardiograms (acquisition interval 105 +/- 28 days) evaluated by the serial method (mean 167 +/- 61 days between interpretations). The same subjects had the initial and 10-month studies (acquisition interval 303 +/- 27 days) compared side-by-side. The specificity of the serial versus side-by-side method for determining change in MR grade was 55.8% versus 93.2% (p < 0.001); TR: 63.8% versus 97.6% (p < 0.001) and AR: 93.7% versus 97.6 (p = 0.08). Notably, most of the change occurred in a range (none versus physiologic/mild) that has limited clinical significance. Furthermore, the percentage of echocardiograms interpreted as nonevaluable was lower with the side-by-side method for MR (5.0% vs. 16.0%, p = 0.06), TR (4.6% vs. 15.5%, p < 0.001) and AR (4.1% vs. 12.3%, p = 0.002). CONCLUSIONS: The side-by-side method of assessing change in valvular regurgitation appears to be the more reliable method with a higher specificity and minimal data loss.

Aortic Valve Insufficiency↗
PubMed2001

Changes in heart rate and heart rate variability before ambulatory ischemic events(1).

OBJECTIVES: The aim of this study was to determine the time course of autonomic nervous system activity preceding ambulatory ischemic events. BACKGROUND: Vagal withdrawal can produce myocardial ischemia and may be involved in the genesis of ambulatory ischemic events. We analyzed trajectories of heart rate variability (HRV) 1 h before and after ischemic events, and we examined the role of exercise and mental stress in preischemic autonomic changes. METHODS: Male patients with stable coronary artery disease (n = 19; 62.1 +/- 9.3 years) underwent 48-h ambulatory electrocardiographic monitoring. Frequency domain HRV measures were assessed for 60 min before and after each of 68 ischemic events and during nonischemic heart rate-matched control periods. RESULTS: High-frequency HRV decreased from -60, -20 to -10 min before ischemic events (4.8 +/- 1.3; 4.6 +/- 1.3; 4.4 +/- 1.2 ln [ms(2)], respectively; p = 0.04) and further from -4, -2 min, until ischemia (4.4 +/- 1.3; 4.1 +/- 1.3; 3.7 +/- 1.2 ln [ms(2)]; p's < 0.01). Low frequency HRV decreases started at -4 min (p < 0.05). Ischemic events occurring at high mental activities were preceded by depressed high frequency HRV levels compared with events at low mental activity (p = 0.038 at -4 min, p = 0.045 at -2 min), whereas the effects of mental activities were not observed during nonischemic control periods. Heart rate variability measures remained significantly decreased for 20 min after recovery of ST-segment depression when events were triggered by high activity levels. CONCLUSIONS: Autonomic changes consistent with vagal withdrawal can act as a precipitating factor for daily life ischemia, particularly in episodes triggered by mental activities.

Aged↗
PubMed2001

Associations of subclinical cardiovascular disease with frailty.

BACKGROUND: Frail health in old age has been conceptualized as a loss of physiologic reserve associated with loss of lean mass, neuroendocrine dysregulation, and immune dysfunction. Little work has been done to define frailty and describe the underlying pathophysiology. METHODS: Frailty status was defined in participants of the Cardiovascular Health Study (CHS), a cohort of 5,201 community-dwelling older adults, based on the presence of three out of five clinical criteria. The five criteria included self-reported weight loss, low grip strength, low energy, slow gait speed, and low physical activity. We examined the spectrum of clinical and subclinical cardiovascular disease in those who were frail (3/5 criteria) or of intermediate frailty status (1 or 2/5 criteria), compared to those who were not frail (0/5). We hypothesized that the severity of frailty would be related to a higher prevalence of reported cardiovascular disease (CVD), as well as to a greater extent of CVD, measured by noninvasive testing. RESULTS: Of 4,735 eligible participants, 2,289 (48%) were not frail, 299 (6%) were frail, and 2.147 (45%) were of intermediate frailty status. Those who were frail were older (77.2 yrs) compared to those who were not frail (71.5 yrs) or intermediate (73.4 yrs) (p < .001). Frailty status was associated with clinical CVD and most strongly with congestive heart failure (odds ratio [OR] = 7.51 (95% confidence interval [CI] = 4.66-12.12). In those without a history of a CVD event (n = 1.259), frailty was associated with many noninvasive measures of CVD. Those with carotid stenosis >75% (adjusted OR = 3.41), ankle-arm index <0.8 (adjusted OR = 3.17) or 0.8-0.9 (adjusted OR = 2.01), major electrocardiography (ECG) abnormalities (adjusted OR = 1.58), greater left ventricular (LV) mass by echocardiography (adjusted OR = 1.16), and higher degree of infarct-like lesions in the brain (adjusted OR = 1.71), were more likely to be frail compared to those who were not frail. The overall associations of each of these noninvasive measures of CVD with frailty level were significant (all p < .05). CONCLUSIONS: Cardiovascular disease was associated with an increased likelihood of frail health. In those with no history of CVD, the extent of underlying cardiovascular disease measured by carotid ultrasound and ankle-arm index, LV hypertrophy by ECG and echocardiography, was related to frailty. Infarct-like lesions in the brain on magnet resonance imaging were related to frailty as well.

Black or African American↗
PubMed2001

Relation of hemodynamics and risk factors to ventricular-vascular interactions in the elderly: the Cardiovascular Health Study.

OBJECTIVE: To investigate the interaction between left ventricular (LV) geometry, carotid structure and arterial compliance in relation to hemodynamic stimuli and risk factors (plasma cholesterol, body mass index, insulin resistance, smoking habit, age, sex and race). DESIGN: Cross-sectional. METHODS: Echocardiography and carotid ultrasound were performed in 2375 elderly subjects without signs or history of prevalent cardiovascular disease, diabetes or renal disease (795 men; 298 non-whites; 1215 hypertensive), from the cohort of the Cardiovascular Health Study. Arterial compliance was estimated by the prognostically validated ratio of stroke volume to pulse pressure (SV/PP) as the percent deviation (Delta%) from the value predicted by individual age, heart rate and body weight. RESULTS: Intima-medial thickness (IMT) was higher in the presence of LV hypertrophy (LVH) in normotensive and hypertensive subjects and was greatest in the presence of concentric LVH. Maximum carotid lumen diameter (CLD) was also higher in the presence of LVH (and was greatest with eccentric LVH, in association with relatively high values for stroke volume). After adjusting for blood pressure, maximum carotid lumen diameter was directly correlated with stroke volume, and IMT to LV mass (all P < 0.001). Similarly, IMT was also related to maximum carotid lumen diameter, independently of prevalent risk factors (P < 0.001). SV/PP-Delta% was reduced in both groups with concentric LV remodeling (both P < 0.0001) or concentric LVH (both P < 0.05). Adjusting for risk factors did not affect these associations in normotensives, but made them insignificant in hypertensives. In normotensives, IMT was inversely related to SV/PP-Delta% (P < 0.001), independently of risk factors, whereas no significant relation was found in hypertensives. CONCLUSIONS: The magnitudes of carotid intima-medial thickness and lumen diameter parallel levels of LV mass and geometry, and are directly related to stroke volume and arterial stiffness; this interaction is most evident in the presence of normal blood pressure, whereas it is affected by other cardiovascular risk factors when arterial hypertension is present.

Aged↗
PubMed2001

Prevalence of clinical and isolated subclinical cardiovascular disease in older adults with glucose disorders: the Cardiovascular Health Study.

OBJECTIVE: Clinical cardiovascular disease (CVD) is highly prevalent among people with diabetes. However, there is little information regarding the prevalence of subclinical CVD and its relation to clinical CVD in diabetes and in the glucose disorders that precede diabetes. RESEARCH DESIGN AND METHODS: Participants in the Cardiovascular Health Study, aged > or = 65 years (n = 5,888), underwent vascular and metabolic testing. Individuals with known disease in the coronary, cerebral, or peripheral circulations were considered to have clinical disease. Those without any clinical disease in whom CVD was detected by ultrasonography, electrocardiography, or ankle arm index in any of the three vascular beds were considered to have isolated subclinical disease. RESULTS: Approximately 30% of the cohort had clinical disease, and approximately 60% of the remainder had isolated subclinical disease. In those with normal glucose status, isolated subclinical disease made up most of the total CVD. With increasing glucose severity, the proportion of total CVD that was clinical disease increased; 75% of men and 66% of women with normal fasting glucose status had either clinical or subclinical CVD. Among those with known diabetes, the prevalence was approximately 88% (odds ratio [OR] 2.46 for men and 4.22 for women, P < 0.0001). There were intermediate prevalences and ORs for those with impaired fasting glucose status and newly diagnosed diabetes. CONCLUSIONS: Isolated subclinical CVD is common among older adults. Glucose disorders are associated with an increased prevalence of total CVD and an increased proportion of clinical disease relative to subclinical disease.

Aged↗
PubMed2000

Efficacy and safety of the novel ultrasound contrast agent perflutren (definity) in patients with suboptimal baseline left ventricular echocardiographic images.

Suboptimal left ventricular (LV) cavity visualization and endocardial border delineation often compromise the clinical utility of echocardiography. This study examines the safety and efficacy of perflutren, a novel ultrasound contrast agent, for LV cavity opacification and endocardial border delineation in patients with suboptimal baseline echocardiograms. In a multicenter, randomized, placebo-controlled, double-blind trial, 211 patients with suspected cardiac disease and suboptimal baseline echocardiograms were enrolled at 17 sites. Two intravenous injections of either placebo (saline) or perflutren (5 or 10 microl/kg) were given approximately 30 minutes apart. Images of the apical 4- and 2-chamber views were acquired and scored. Perflutren opacified the LV cavity after both dosages (5 and 10 microl/kg dosages). Clinically useful contrast was observed in 89% of patients who received perflutren and in 0% of patients who received placebo (p < 0.01). Quantitative assessment of LV opacification with videodensitometry showed similar results. The mean duration of clinically useful contrast was 90 seconds. Improvement in endocardial border delineation was demonstrated in 91% of patients who received perflutren and in 12% of those who received placebo (p < 0.001). Following perflutren, an average of 4 more segments per patient were evaluable compared with baseline. Salvage of nondiagnostic baseline examinations by perflutren was demonstrated in 48% of eligible subjects. The safety profile of perflutren was similar to placebo. These data indicate that administration of perflutren to patients with suboptimal baseline images is well tolerated and provides substantial LV cavity opacification and improvement in endocardial border delineation.

Contrast Media↗
PubMed2000

Relationship between left ventricular mass and hemodynamic responses to physical and mental stress.

OBJECTIVE: Increased left ventricular mass (LVM) is predictive of future cardiac morbidity and mortality. Although casual and ambulatory blood pressure (BP) predict LVM, other hemodynamic determinants of LVM are incompletely understood. The present study examines laboratory-induced hemodynamic responses (to exercise, cold, and mental stress) and 24-hour ambulatory measures as predictors of LVM. METHODS: Thirty-six healthy non-hypertensive subjects (mean age 33.9 +/- 9.4 years; 23 women, 13 men) were tested with mental stress, cold pressor, and treadmill exercise in the laboratory and 24-hour ambulatory BP monitoring. LVM was measured using two-dimensional targeted M-mode echocardiography and indexed for body surface area (LVMI). RESULTS: All laboratory tasks produced significant hemodynamic responses (p's < 0.01). Systolic blood pressure responses to mental stress (r = 0.42, p < 0.01) and cold pressor (r = 0.34, p < 0.05) were significantly related to LVM. After adjusting for body size, the mental stress-induced SBP responses was the only significant predictor of LVMI (r = 0.32, p < 0.05). Exercise SBP responses were associated to LVMI in men (r = 0.63, p = 0.02), but not in women (r = 0.02, p = n.s.). Multivariate regression analyses revealed that SBP during mental stress was significantly predictive of LVMI (beta = 0.65, p = 0.05), independent of baseline SBP, 24-hour ambulatory SBP, and other control variables. CONCLUSION: The present results indicate that SBP responses to mental stress are significantly related to LVM among healthy individuals, independently of baseline SBP, 24-hour ambulatory BP, age, body size, and sex. Blood pressure responses to exercise show a robust association with LVM in men but not in women. Hemodynamic responses elicited during laboratory tasks may therefore reveal important information about the pathophysiological processes involved in the development of cardiac end-organ damage.

Adaptation, Psychological↗
PubMed2000

Predictors of congestive heart failure in the elderly: the Cardiovascular Health Study.

OBJECTIVES: We sought to characterize the predictors of incident congestive heart failure (CHF), as determined by central adjudication, in a community-based elderly population. BACKGROUND: The elderly constitute a growing proportion of patients admitted to the hospital with CHF, and CHF is a leading source of morbidity and mortality in this group. Elderly patients differ from younger individuals diagnosed with CHF in terms of biologic characteristics. METHODS: We analyzed data from the Cardiovascular Health Study, a prospective population-based study of 5,888 elderly people >65 years old (average 73 +/- 5, range 65 to 100) at four locations. Multiple laboratory measures of cardiovascular structure and function, blood chemistries and functional assessments were obtained. RESULTS: During an average follow-up of 5.5 years (median 6.3), 597 participants developed incident CHF (rate 19.3/1,000 person-years). The incidence of CHF increased progressively across age groups and was greater in men than in women. On multivariate analysis, other independent predictors included prevalent coronary heart disease, stroke or transient ischemic attack at baseline, diabetes, systolic blood pressure (BP), forced expiratory volume 1 s, creatinine >1.4 mg/dl, C-reactive protein, ankle-arm index <0.9, atrial fibrillation, electrocardiographic (ECG) left ventricular (LV) mass, ECG ST-T segment abnormality, internal carotid artery wall thickness and decreased LV systolic function. Population-attributable risk, determined from predictors of risk and prevalence, was relatively high for prevalent coronary heart disease (13.1%), systolic BP > or =140 mm Hg (12.8%) and a high level of C-reactive protein (9.7%), but was low for subnormal LV function (4.1%) and atrial fibrillation (2.2%). CONCLUSIONS: The incidence of CHF is high in the elderly and is related mainly to age, gender, clinical and subclinical coronary heart disease, systolic BP and inflammation. Despite the high relative risk of subnormal systolic LV function and atrial fibrillation, the actual population risk of these for CHF is small because of their relatively low prevalence in community-dwelling elderly people.

Aged↗
PubMed2000

Race- and sex-specific ECG models for left ventricular mass in older populations. Factors influencing overestimation of left ventricular hypertrophy prevalence by ECG criteria in African-Americans.

The validity of the reported high prevalence of left ventricular hypertrophy (LVH) among African-American men and women has been questioned owing to conflicting echocardiographic evidence. We used echocardiographic left ventricular mass (LVM) from M-mode measurements to evaluate associations between LVM, body size, and electrocardiographic (ECG) variables in 3,627 white and African-American men and women 65 years of age and older who were participants of the Cardiovascular Health Study (CHS), a multicenter cohort study of risk factors for coronary heart disease and stroke. ECG amplitudes used in LVH criteria were substantially higher in African-Americans, with apparent LVH prevalence 2 to 3 times higher in African American men and women than in white men and women, although there was no significant racial difference in echocardiographic LVM. The higher apparent LVH prevalence by Sokolow-Lyon criteria in African-American men is in part owing to smaller lateral chest diameter. In women, reasons for racial differences in ECG LVH prevalence remain largely unexplained although a small part of the excess LVH in African-American women by the Sokolow-Lyon criteria appears to be owing to a larger lateral chest semidiameter in white women. ECG variables alone were too inaccurate for LVM prediction, and it was necessary to incorporate in all ECG models body weight that was properly adjusted for race and sex. This resulted in modest LVM prediction accuracy, with R-square values ranging from .22 to .36. Race- and sex-specific ECG models introduced for LVM estimation with an appropriate adjustment for body size differences are expected to facilitate evaluation of LVH status in contrasting racial population groups.

Age Factors↗
PubMed1999

Prognostic value of mental stress testing in coronary artery disease.

This study assesses the prognostic value of mental stress-induced ischemic left ventricular wall motion abnormalities and hemodynamic responses in patients with stable coronary artery disease (CAD). Seventy-nine patients (76 men and 3 women) with prior positive exercise test results were exposed to mental arithmetic and a simulated public speech stress in 2 prior studies. Ischemic wall motion abnormalities were monitored using echocardiography or radionuclide ventriculography (RNV). During mental stress testing, new or worsened ischemic wall motion abnormalities to mental stress and exercise were ascertained, as were peak changes in blood pressure and heart rate to mental stress. The occurrence of subsequent cardiac events (including cardiac death, nonfatal myocardial infarction, or revascularization procedures) was ascertained. New cardiac events were observed in 28 of 79 patients (35%) after a median follow-up duration of 3.5 years (range 2.7 to 7.3). Survival analysis indicated that 20 of 45 patients with mental stress ischemia (44%) experienced new cardiac events more frequently than those without mental stress ischemia (8 of 34; 23%; p = 0.048). Type of cardiac event did not differ between mental stress-positive and stress-negative patients. After controlling for baseline blood pressure and study group status (echocardiography vs RNV), there was a significantly higher relative risk of subsequent events for patients with high versus low peak stress-induced diastolic blood pressure responses (RR = 2.4, confidence interval 1.1 to 5.2; p = 0.03). These results demonstrate that ischemic and hemodynamic measures obtained from mental stress testing may be useful in assessing prognosis in CAD patients with prior positive exercise test results.

Adult↗
PubMed1999

Epidemiological approach to quality assessment in echocardiographic diagnosis.

OBJECTIVES: This study sought to determine whether statistical analysis of a computerized clinical diagnostic database can be used as a tool for quality assessment by determining the contribution of reader bias to variance in diagnostic output. BACKGROUND: In industry, measurement of product uniformity is a key component of quality assessment. In echocardiography, quality assessment has focused on review of small numbers of cases, or prospective determination of reader variability in selected and relatively small subsets. However, diagnostic biases in clinical practice might be discerned utilizing large computerized databases to determine interreader differences in diagnostic prevalence and, with use of appropriate statistical methods, to determine the association of reader selection with diagnostic prevalence independently of other covariates. METHODS: We analyzed 6,026 echocardiograms in a computerized database, read by one of three level 3 (American Society of Echocardiography) readers, for differences in frequency among four coded echocardiographic diagnoses: mitral valve prolapse, valvular vegetations, left ventricular (LV) thrombus, and LV regional wall-motion abnormality. RESULTS: Significant differences (up to fourfold) were found between readers, which persisted after statistical adjustment for those population characteristics, which differed slightly between readers. The low population prevalence of these conditions would have made it unlikely that these interreader differences could be detected by nonstatistical methods. Additionally, chamber dimensions differed between readers and were not normally distributed. CONCLUSIONS: Statistically based quality assessment analysis of computerized clinical databases facilitates ongoing monitoring of interreader bias despite low diagnostic prevalence, and targets opportunities for subsequent quality improvement.

Diagnostic Errors↗
PubMed1999

Traditional risk factors and subclinical disease measures as predictors of first myocardial infarction in older adults: the Cardiovascular Health Study.

BACKGROUND: Risk factors for myocardial infarction (MI) have not been well characterized in older adults, and in estimating risk, we sought to assess the individual and joint contributions made by both traditional risk factors and measures of subclinical disease. METHODS: In the Cardiovascular Health Study, we recruited 5888 adults aged 65 years and older from 4 US centers. At baseline in 1989-1990, participants underwent an extensive examination that included traditional risk factors such as blood pressure and fasting glucose level and measures of subclinical disease as assessed by electrocardiography, carotid ultrasonography, echocardiography, pulmonary function, and ankle-arm index. Participants were followed up with semiannual contacts, and all cardiovascular events were classified by the Morbidity and Mortality Committee. The main analytic technique was the Cox proportional hazards model. RESULTS: At baseline, 1967 men and 2979 women had no history of an MI. After follow-up for an average of 4.8 years, there were 302 coronary events, which included 263 patients with MI and 39 with definite fatal coronary disease. The incidence was higher in men (20.7 per 1000 person-years) than women (7.9 per 1000 person-years). In all subjects, the incidence was strongly associated with age, increasing from 7.8 per 1000 person-years in subjects aged 65 to 69 years to 25.6 per 1000 person-years in subjects aged 85 years and older. Glucose level and systolic blood pressure were associated with the incidence of MI, but smoking and lipid measures were not. After adjustment for age and sex, the significant subclinical disease predictors of MI were borderline or abnormal ejection fraction by echocardiography, high levels of intimal-medial thickness of the internal carotid artery, and a low ankle-arm index. Forced vital capacity and electrocardiographic left ventricular mass did not enter the stepwise model. Excluding subjects with clinical cardiovascular diseases such as prior angina or congestive heart failure at baseline had little effect on these results. Risk factors were generally similar in men and women. CONCLUSIONS: After follow-up of 4.8 years, systolic blood pressure, fasting glucose level, and selected subclinical disease measures were important predictors of the incidence of MI in older adults. Uncontrolled high blood pressure may explain about one quarter of the coronary events in this population.

Age Distribution↗