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Many studies rely on self-reported smoking status. We hypothesized that patients with acute coronary syndrome (ACS), a smoking-related condition, would be more prone to misclassify themselves as ex-smokers, because of pressure to quit. We compared patients admitted with ACS with a general population survey conducted in the same country at a similar time. We determined whether ACS patients who classified themselves as ex-smokers (n = 635) were more likely to have cotinine levels suggestive of smoking deception than self-reported ex-smokers in the general population (n = 289). On univariate analysis, the percentage of smoking deceivers was similar among ACS patients and the general population (11% vs. 12%, p = .530). Following adjustment for age, sex and exposure to environmental tobacco smoke, ACS patients were significantly more likely to misclassify themselves (adjusted OR = 14.06, 95% CI 2.13-93.01, p = .006). There was an interaction with age whereby the probability of misclassification fell significantly with increasing age in the ACS group (adjusted OR = 0.95, 95% CI 0.93-0.97, p<.001), but not in the general population. Overall, smoking deception was more common among ACS patients than the general population. Studies comparing patients with cardiovascular disease and healthy individuals risk introducing bias if they rely solely on self-reported smoking status. Biochemical confirmation should be undertaken in such studies.

Background: Diagnosing suspected left ventricular systolic dysfunction (LVSD) in the community is a challenge for GPs. We developed and validated a clinical prediction rule (CPR) for LVSD based on history, examination and electrocardiogram (ECG)., Methods: Prospective cohort studies of 458 symptomatic patients (derivation cohort) and 535 patients (validation cohort) in 26 general practices in Tayside and Fife, Scotland. All patients underwent a structured clinical examination and ECG and the 'reference standard' investigation of echocardiography to establish the presence of LVSD., Results: Four elements from the clinical history and examination were all independently associated with LVSD--male sex [adjusted odds ratio (OR) 2.5; 95% CI 1.1, 5.0], presence of orthopnoea (OR 5.4; 1.9, 13.8) history of myocardial infarction (OR 5.6; 2.3, 13.6) and elevated jugular venous pulsations (OR 15.1; 4.6, 49.3). Addition of ECG (OR 20.6; 2.7, 158.6) provides important diagnostic information in terms of probability of LVSD. A CPR based on the presence or absence of these five elements will generate probabilities ranging from 1% to 97% for LVSD when applied to an individual patient. In the validation cohort, the model under-predicted the probability of LVSD, particularly at lower levels of expected risk, reflecting differences in the risk-factor profiles of the derivation and validation cohorts., Conclusions: The derived CPR provides quantitative estimates of post-test probability for LVSD. This rule requires further validation in other populations and settings because of the difficulties encountered in the validation cohort.

Background: In coronary artery disease (CAD), a potentially reversible factor leading to cardiac death is left ventricular hypertrophy (LVH). However, LVH will only have a large impact overall in CAD if it is highly prevalent. Therefore we aimed to assess the prevalence of LVH in patients with stable, treated angina and its relationship with blood pressure (BP)., Methods: Three hundred twenty-two consecutive patients with angiographically confirmed coronary artery disease were recruited. Echocardiographic LV mass was performed and correlated with both office and 24-h ambulatory BP., Results: Of the 267 patients with LV mass measurements, 195 (73%) had LVH. The mean 24-h ambulatory BP reading was systolic 125 +/- 12 mm Hg and diastolic 68 +/- 8 mm Hg in the LVH group. Of the LVH patients 62% had a nonhypertensive 24-h BP reading. On multivariate logistic regression analysis, factors independently related to LVH were history of hypertension (odds ratio [OR] 1.848, 95% confidence interval [CI] 1.051-3.248), body mass index (OR 1.085, 95% CI 1.011-1.165), and age (OR 1.039, 95% CI 1.004-1.076)., Conclusions: We conclude that echo LVH is very common in patients with stable, treated angina and the majority of these patients had a nonhypertensive BP at the time of study. Studies are now required to determine whether identifying and vigorously treating LVH in CAD would reduce the risk of premature death in these patients.

Background: Smaller echocardiography machines, when used in hospitals, are accurate for detecting left ventricular dysfunction and valvular disease. This paper assessed the detection of left ventricular dysfunction and of valvular disease in the community setting by a smaller machine., Aims: To measure the agreement in patients with suspected heart failure between community echocardiography and traditional echocardiography in the hospital in detecting left ventricular dysfunction and significant valve disease., Methods: Suspected heart failure patients were referred to one of the authors (SJ) for community echocardiography using a Siemens Cypress machine. The patients had a second echocardiogram in the hospital by another sonographer who was blinded to the results of the first echocardiogram. The reports of the two sonographers were assessed for agreement using kappa statistics., Results: 458 patients had a community echocardiogram and 136 agreed to a second echocardiogram in the hospital. There was excellent agreement, kappa = 0.87 (0.06 SE), for the detection of left ventricular dysfunction between community echocardiography and the hospital machine. The detection of significant valvular disease was good, kappa = 0.75 (0.06) between the community echocardiogram and hospital machines., Conclusions: In suspected heart failure patients, community echocardiography gives comparable results to traditional hospital echocardiography for left ventricular dysfunction detection and for significant valvular disease detection.

Aims: To investigate the relationship between serum markers of Chlamydia pneumoniae infection and subsequent coronary events., Methods and Results: In a nested case-control study, based on the Scottish Heart Health Study cohort, we estimated IgG, IgA and IgM antibodies to C. pneumoniae, and circulating immune complexes containing C. pneumoniae antigen in baseline serum samples from 217 cases experiencing a subsequent coronary event during follow-up (mean 7.5 years) and from their matched controls. In men, the proportion of specimens positive for IgG, IgA and IgM antibodies showed no case-control differences (80% vs 80%, 57% vs 53% and 3% vs 3%, respectively). The odds ratio for a coronary event was 1.00 (95% confidence interval 0.59-1.69) for the presence of IgG antibodies to C. pneumoniae; 1.21 (0.76-1.92) for IgA and 0.75 (0.17-3.35) for IgM. Similar results were seen in women. The proportion of specimens with circulating immune complexes with C. pneumoniae antigen also showed no case-control differences (12% vs 12%, both sexes combined) with an odds ratio of 1.00 (0.57-1.76)., Conclusion: Prior infection with C. pneumoniae, as estimated by these markers, does not appear to be a risk factor for subsequent coronary heart disease., (Copyright 2001 The European Society of Cardiology.)

Aims: Resting plasma levels of atrial natriuretic peptide and B-type natriuretic peptide rise with left ventricular dysfunction, but little is known about effects of cardiac ischaemia on atrial natriuretic peptide and B-type natriuretic peptide levels during exercise. We investigated exercise levels of atrial natriuretic peptide and B-type natriuretic peptide in patients with suspected angina to determine whether these measurements could improve non-invasive assessment of coronary disease severity., Methods and Results: One hundred patients performed an exercise test (Bruce protocol) within 2 weeks of coronary angiography. Plasma levels of atrial natriuretic peptide and B-type natriuretic peptide were measured at rest and at peak exercise. Multivariate regression analysis was used to assess effects of age, sex, coronary anatomy, exercise time and ventricular function on atrial natriuretic peptide and B-type natriuretic peptide levels. Increasing age and female sex were significantly associated with higher resting atrial natriuretic peptide levels; age alone was associated with higher exercise atrial natriuretic peptide levels. As expected, left ventricular end-diastolic pressure and disease of left anterior descending and circumflex coronary arteries were associated with increased resting B-type natriuretic peptide levels. However, the usual rise in B-type natriuretic peptide levels during exercise was independently reduced by disease of the right coronary artery., Conclusion: This paradoxical effect of right coronary artery disease limits the value of natriuretic peptide measurements as predictors of coronary disease severity. Impaired release of B-type natriuretic peptide may reduce exercise tolerance in patients with right coronary artery disease.