Causal relationship between influenza infection and risk of acute myocardial infarction: pathophysiological hypothesis and clinical implications

Presently several evidences support an association between acute myocardial infarction and influenza infection. The pathophysiology rationale rests on the release of inflammation cytokines, rupture of atherosclerotic plaque, and triggering of prothrombotic events leading to coronary artery occlusion. Several observational evidences support a potential role of influenza vaccine in cardiovascular prevention. It is estimated that the efficacy of influenza vaccine in preventing myocardial infarction could range between 15% and 45%. Notwithstanding the clear recommendation of numerous guidelines concerning patients with cardiovascular diseases, vaccination rates are still low in the high-risk groups. Influenza vaccine as preventive measure of cardiovascular disease still awaits support from randomized clinical trials. Nonetheless, considering the favourable cost-efficacy and safety profile of influenza vaccination, its use should be encouraged in everyday clinical practice.