Decompensated heart failure affects 5 million Americans and nearly 15 million individuals worldwide. Heart failure can be attributed to numerous etiologies, with autoimmune conditions representing a rare category of acute decompensations. Here, we report of case of a 66-year-old woman who presented with acute decompensated heart failure as a result of a rare vasculitis known as idiopathic aortitis. In addition to describing the case, we highlight the importance of proper ascending aorta evaluation in patients presenting with new onset heart failure, especially in the setting of aortic regurgitation. We use this case to discuss the entity of idiopathic aortitis, and review the literature on its clinical manifestations and long-term management.