The secondary goal of the program is to evaluate the health related quality of life (HRQOL) impact associated with early invasive intervention, in comparison to primary AAD therapy. This analysis will be centered on an evaluation of generic and disease-specific HRQOL instruments in order to determine the impact of an early invasive approach. A secondary benefit is the derivation of a Quality Adjusted Life Years (QALYs) score, which can be used as a summary measure of health outcome and to inform subsequent healthcare resource allocation decisions.