Current clinical use of intravascular ultrasound imaging to guide percutaneous coronary interventions (update).

There are 3 main reasons to promote the practical application of IVUS during PCI. First reason is to understand the mechanism of vessel dilatation. Even if angiographic stenoses are similar, their pathophysiologies are different. It is important to understand what can happen by dilating coronary artery with balloon/stent, and to develop a strategy to achieve the maximum effect. Second reason is to anticipate possible complications and to reduce them in advance. In that case, we can deal with it as calmly as possible. Third reason is to validate the PCI performed. This should lead to further improvements of the procedures, which in turn will lead to improved short- and long-term prognosis. Then, high-quality PCI could be possible. This review summarizes the standard usage of IVUS in routine clinical practice and the use of IVUS in specific situations, especially complex lesions.