We present the case of a 74-year-old female patient with a 50 mm ascending aortic aneurysm who underwent ascending aorta replacement. During routine open heart surgery, suboptimal flow in the cardiopulmonary bypass circuit, led to the discovery of a type B aortic dissection with substantial flow in the false lumen. Conservative management was chosen, focusing on blood pressure control in the ICU. Despite an initial uneventful recovery the patient developed malperfusion syndrome prompting consideration of endovascular repair. Following a temporary improvement, malperfusion symptoms recurred, leading to a successful endovascular repair, with complete thrombosis of the false lumen.