SUMMARY Sixteen healthy subjects, ages 18-35 years, were studied in the supine position by means of systolic time intervals and echocardiography before and after smoking a high-nicotine cigarette (2.5 mg nicotine) and a tobacco cigarette of very low nicotine content (< 0.02 mg nicotine) to assess and compare the immediate effects upon left ventricular function.Smokers (n = 12) and nonsmokers (n = 4) behaved alike. High-and low-nicotine cigarettes both caused significant increases in heart rate, systolic and diastolic blood pressure and the triple product (systolic blood pressure X left ventricular ejection (LVET) X heart rate), prolonged LVETc and decreased the preejection period (PEP) and PEP/LVET. In addition, smoking a nicotine reference cigarette increased the echocardiographically derived LV end-diastolic volume by 7.5%, augmented ejection fraction by 4%, while significantly enhancing mean normalized circumferential fiber shortening by 12.5% and mean normalized posterior wall velocity by 9%. Smoking a tobacco cigarette of ultra-low nicotine content resulted in comparable increases in ejection fraction and mean circumferential fiber shortening, albeit on the basis of a significant decrease in end-systolic volume without alteration in end-diastolic volume.These data suggest that in the supine position smoking a high-nicotine cigarette acutely increases venous return and augments the principal determinants of myocardial oxygen consumption heart rate, contractility, preload and afterload and that cigarette smoke may contain inotropic and chronotropic substances other than nicotine.CIGARETTE SMOKING has been linked epidemiologically as a risk factor in the development of myocardial infarction and has been associated with an increase in sudden death among chronic cigarette consumers.', I The cause of this increased morbidity and mortality has not been established; among the factors under consideration are hypoxemia,3 enhanced cor-
Microvascular angina is associated with enhanced Na+/H+ exchange in erythrocytes, probably due to more extensive phosphorylation of the membrane antiporter sites.
The role of negative affectivity on patients' perceptions of and behavior during asthma attacks was explored among 47 asthmatic subjects. Patients completed 17 to 30 daily questionnaires assessing negative affect, asthma perception, additional drug intake, search for medical assistance, and peak-flow measures of respiratory distress. Asthma perceptions were correlated with negative affect and educational level; the perception of the asthma severity, but not negative affect, did predict behavior during an attack. The importance of symptom perceptions for the clinical management of chronic asthma is underscored.
A semiotic conceptualization of pain in the chronic pain syndrome is proposed. It is suggested that among chronic pain patients pain ceases to be an icon or an index and acquires a symbolic structure: this transformation interferes with the usual patient-physician relationship. The semiotic perspective on the structure of meaning in the chronic pain syndrome underlines the need to include a psychotherapeutic approach in the patient-physician relationship; specific aspects of the approach to chronic pain as a symbolic communication are discussed.
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