on October 8, 2009
Published online before print October 8, 2009, doi: 10.1161/ATVBAHA.109.195024
Submitted on March 26, 2009
Accepted on September 15, 2009
Effects of Cigarette Smoke Exposure on Clot Dynamics and Fibrin Structure. An Ex Vivo Investigation
Rajat S. Barua ;
From the Division of Cardiovascular Medicine (R.S.B., F.S., S.S., G.H., U.J., C.B., J.A.A.), University of California San Francisco, Fresno; and San Joaquin Agricultural Sciences Center (D.M.), Parlier, Calif.
* To whom correspondence should be addressed. E-mail: jamambrose{at}yahoo.com.
Objectives—The purpose of this study was to examine the effect of cigarette smoke exposure (CSE) on clot dynamics and fibrin architecture and to isolate the relative contribution of platelets and fibrinogen to clot dynamics.
Methods and Results—From young healthy males smokers (n=34) and nonsmokers (n=34) a baseline blood was drawn, and smokers had another blood draw after smoking 2 regular cigarettes. Using thromboelastography (TEG) the degree of platelet-fibrin interaction was measured. In additional experiments, abciximab (20 μg/mL) was added to the smokers samples (n=27) to reduce the effects of platelet function from the TEG parameters. The maximum clot strength (G) obtained with abciximab measured mainly the contribution of fibrinogen to clot strength (GF). By subtracting GF from G, the contribution of platelets to clot strength (GP) was presumed. A significant difference was found for all TEG parameters between nonsmokers versus postsmoking and pre- versus postsmoking samples. Postsmoking both GF and GP were significantly higher as compared to presmoking. On electron microscopy and turbidity analysis, postsmoking fibrin clots were significantly different compared to presmoking and nonsmoking samples.
Conclusions—Acute CSE changes clot dynamics and alters fibrin architecture. Both functional changes in fibrinogen and platelets appear to contribute to heightened thrombogenicity after acute CSE.
Key words: smoking • thrombosis • platelet • fibrinogen