Sonographic and Angiographic Features of Intramural Hematoma as a Cause of Failed Coronary Angioplasty

A characteristic feature of a specific type of dissection after PTCA was observed in seven cases with severe obstruction of the vessel segments proximal and/or distal to the dilatation site. The underlying cause in the absence of an angiographically visible dissection flap was revealed by intravascular ultrasound. The obstruction was caused by an extraluminal obstruction by an echodense mass increasing in size with time, and without a dissection flap even as assessed by intravascular ultrasound. This phenomenon was interpreted as an intramural hematoma extending between media and adventitial border of the vessel. In six of seven cases, bailout therapy by either stenting or redilatation and creation of a typical dissection flap relieved the vessel obstruction. In one case of extension of the hematoma into the left main coronary artery, CABG was performed. Intravascular ultrasound provided a conclusive insight into the underlying morphology of failed PTCA in cases without angiographic features of a dissection. It helped in deciding and controlling the bailout strategy, which was the stenting of the entry into the hematoma at the initial dilatation site.