Porcine Left Atrial Wall Stress After Ventricular Tachypacing Mimicking the Effects of Early Atrial Fibrillation

Atrial Fibrillation (AF) is the cardiac arrhythmia most commonly encountered in clinical practice. Current statistics referring to the US population indicate a prevalence of AF up to 2.2 million people, projected to increase to 2.66 million by the end of 2010. AF has a high impact on society in terms of human costs, with an annual mortality rate of 11,438 patients. AF also increases the risk of ischemic stroke at least by a factor of 4 and it is responsible for at least 15% of all ischemic strokes, which represent the main cause of long-term disability and one of the main contributors to health care costs [1]. AF results from the synergic action of electrophysiological, biochemical and structural remodeling. Ventricular tachypacing (VTP) has been successfully used in animal models to reproduce relevant features observed in patients suffering from AF, such as ion-channel alterations, fibrosis development and atrial dilatation [2] [3].