Effect of Acute Smoking on Diastolic Function

Background: Smoking is a known risk factor of atherosclerosis, endothelial dysfunction, athermanous plaque rupture, unstable coronary syndrome and sudden cardiac death. Methods: The present study comprised 40 randomly selected healthy male hospital staff without a history of hy- pertension or cardiac or pulmonary disease. Participants were divided into two groups. The first group included 20 professional smokers (at least 5 pack/year till the time of study) and the second group consisted of 20 non- professional smokers defined as 0.5 pack/ year or less till the time of study. Participants were instructed not to smoke for 6 hours before the study. Patients underwent echocardiography before smoking. The participants were then asked to smoke a whole cigarette. After smoking, echocardiography was repeated within 7 to 15 minutes. Echocardiographic indices of diastolic function (E wave, A wave, Ea, E/A ratio and deceleration time) were measured before and after smoking. Results: There was no statistically significant difference in the baseline measures in both groups before smoking and also there was no significant difference between measures in the two groups after smoking. The analysis of the pooled data from two groups showed that, smoking resulted in significant increase of heart rate (P<0.001). A wave, E wave, Ea, E/A ratio and deceleration time changed significantly after smoking (P<0.001, P=0.027, P=0.011, P<0.001 and P<0.001 respectively). Conclusion: Smoking of only a cigarette in both professional and nonprofessional smokers, resulted in the same significant diastolic dysfunction.