Abstract

Introduction

The conventional risk factors, like age, smoking, hyperlipidaemia do not explain all the mortality and morbidity due to coronary artery disease^[1]. Recently non-conventional factors like plasma fibrinogen, C reactive protein, homocysteine have been recognized as independent risk factors to explain the present epidemic of coronary artery disease in Indian patients.^[2] Serum fibrinogen is a newer independent risk factor for CAD^[3]. Fibrinogen increases the blood viscosity and plays a key role in thrombosis, both of which promotes coronary artery atherosclerosis.

In cardiovascular disease, fibrinogen has been mainly considered as being involved in thrombotic occlusion and hence in the final stage of atherosclerosis^[5]. Fibrinogen is a well-known acute phase protein and the most abundant coagulation factor in the blood. As a short half-life protein and indicator of procoagulant state which was swiftly consumptions, circulating Fib was not only involved in acute phase of acute coronary syndrome (ACS) but also participated in chronic inflammatory response, which could accelerate the progress of atherosclerosis, and subsequently lead to the development of clinical CAD.^[6]

Experimental studies have also suggested that fibrinogen and fibrin degradation products may increase coronary plaque vulnerability by stimulating coagulation, platelet aggregation, and vascular endothelial dysfunction.^[7] However a number of investigators have suggested that fibrinogen may play a more active role in the development and progression of atherosclerotic plaque.^[8] Smooth muscle cell proliferation stimulated by fibrinogen, suggests that fibrinogen is involved in the earliest stage of plaque formation.^[9]