Evaluation of microvascular obstruction after acute myocardial infarction with cardiac magnetic resonance imaging, 201-thallium and 99 m-technetium pyrophosphate scintigraphy by Ohnishi Yuko, Kobayashi Isshi, Nakamura Hiroaki, Kawashima Tomoyuki, Kato Nobutaka, Ohnishi Takayuki, Umezawa Shigeo, Niwa Akihiro