Intravascular ultrasound (IVUS) examination reverses therapeutic decision from percutaneous intervention to a surgical approach in patients with alterations of the left main stem

Intravascular ultrasound (IVUS) represents a new method to assess vessel lu men and wall morphology. To prospectively evaluate the usefulness of IVUS f or further therapeutic decisions in left main stem (LM) lesions with unclea r angiographic definition, this study was launched. We studied 56 patients with significant stenosis of the LAD and/or LCX arteries and questionable L M morphology. 30-MHz IVUS catheters with 2.9 or 3.2 F outer diameters were used. A significant luminal reduction of the left main stem was defined as an area stenosis greater than 50% or a minimal luminal diameter smaller tha n 3 mm as determined by IVUS. 36 of 56 patients (61 %) fulfilled these crit eria. Additionally, 12 patients showed a ruptured plaque within the LM. 30 of these 36 patients were originally thought to be candidates far angioplas ty. After positive IVUS 34 of these 36 patients were sent to surgery. No pe rioperative ischemic complications occurred. In angiographically unclear le ft main stem findings, IVUS establishes a definitive diagnosis. After IVUS confirmation of significant left main stem pathology operative management s hould be the preferred approach as compared to transluminal coronary interv entions. However, prospective randomized studies are needed to define the m ost efficient approach.