**1. Introduction**

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#### **1.1. Health impact of cardiovascular disease (CVD)**

Cardiovascular disease (CVD) is the principal cause of death worldwide, representing nearly 30% of the annual global mortality and 10% of global health burden [1]. The cur‐ rent status of CVD is now on international scale; which can be considered as the com‐ monest chronic illness in both developed and developing countries, causing the most deaths and the greatest impact on morbidity [2]. In 2006, CVD was the leading cause of death for Canadians, representing 30% of all deaths [3]. A total number of 1.3 million Canadians are diagnosed having heart disease accounting for 5% among those above 12 years and 23% at 75 years and older. The increased rate of obesity and diabetes com‐ bined with further aging of the population will likely lead to an increase in the number of people with CVD in the future. This will compromise the health of Canadians, put a strain on the health care system, and have a significant economic impact on Canada [4]. Similarly, over the past five decades the prevalence of CVD has steadily increased in eco‐ nomically developing countries [5]. These countries will account for 76% of an estimated 25 million death due to CVD in 2020 [6]. On an international basis, by 2020 CVD will reach nearly epidemic proportions and become the cause of more deaths, disability and economic loss than any others group of diseases. The number of fatalities by CVD pro‐ jected to increase to over 20 million a year by 2020 and over 24 million a year by 2030 [7]. Apparently, understanding the aetiology of CVD and accordingly develop preventive and therapeutic approaches to address this health threat continues to be critically impor‐ tant in the next decades although significant achievements have been made in the past decades.

© 2013 Nair and Wang; licensee InTech. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2013 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
