P-40: Acute and chronic detrimental effect of smoking on aortic elasticity

Abstract

Aortic elasticity is an important determinant of left ventricular performance and coronary blood flow and has been identified as an independent prognosticator of cardiovascular risk. The effect of smoking on aortic elastic properties has not been fully elucidated.

In the acute phase of the study 20 subjects (all male 40±4.2 yrs) were studied according to a randomized, sham-procedure controlled, crossover design. Aortic elastic properties were evaluated at baseline and 10 minutes after smoking one standard cigarette (1.1 mg nicotine) or sham-smoking. In the chronic study, 95 current smokers (all male, 38.2±8.3 yrs) were compared with 45 non smokers (all male, 38.4±9.7 yrs). Aortic elastic properties were evaluated by measuring aortic distensibility (ascending aorta diameters were measured by transthoracic echocadiography and pressures were measured by sphygmomanometry).

Acute Study:

Distensibility was reduced significantly with smoking (from 2.36±0.81 to 1.72±0.82 10-6.cm2.dyn-1, P=0.01), whereas no changes were observed with sham-smoking.

Chronic Study:

Smokers had impaired aortic elastic properties compared with non-smokers (distensibility: 2.15±0.97 vs. 2.75±1.07 10-6.cm2.dyn-1, P<0.005). Multiple linear regression analysis showed that pack-years of smoking were inversely associated with aortic distensibility (standardized beta = -0.18, p = 0.037), after controlling for age, and body mass index of the participants. Partial correlation analysis revealed that the number of cigarettes smoked was more strongly related with distensibility (partial r = -0.21 vs. r = -0.12), than the years of smoking (partial r = -0.24 vs. r = -0.19).

Smoking has a both acute and chronic detrimental effect on aortic elastic properties. Intensity and duration of smoking are inversely associated with aortic elastic properties. These findings add to the deleterious consequences of smoking on the cardiovascular system.

Aortic distensibility, Smoking