Exercise electrocardiogram in asymptomatic middle-aged Egyptian smokers

ABSTRACT

50 asymptomatic middle-aged smokers and 15 non-smokers [as a control group] were included in our work. All were males, and their ages ranged from 35 to 55 years with a mean of 42 +/- 6.52 years for the smokers and of 42.3 +/- 6.36 years for the non-smokers. All our subject were free of any suspicion of being cardiac patients. All were subjected to careful history taking including detailed smoking history, thorough physical examination, resting surface ECG and exercise testing using the electric bicycle ergometer. Our results were analysed using the [Chi-square] and the mean [t] student tests. In our study, the relative body weight was significantly lower [P<0.05] in smokers with an inverse relation between it and the smoking rate and duration. The prevalence of latent ischaemia was 6% in smokers and 0% in non-smokers. The incidence of exercise induced arrhythmia was also higher in smokers with a significant difference [P<0.05] achieved only by those consuming >40 cig./day. Smokers consuming >40 cig./day and those with smoking duration >20 years acheived maximal exercise systolic BP which was significantly higher [P<0.05] then, non-smokers. Also, smokers with more than 40 cigarettes smoked per day showed a significantly lower exercise duration than non-smokers [P<0.05]. Our results prove that cigarette smoking is deleterious to CVS, and this is more pronounced in heavy smokers. Using only ST segment depression as a criterion for abnormal ECG response, the incidence of latent ischaemia was 6% and 0% for smokers and non-smokers respectively. Thus, it is clear that exercise ECG test is not an appropriate "screening" test for asymptomatic subjects, especially those without CAD risk factors