論文種別	原著(症例報告除く)
言語種別	英語
査読の有無	査読あり
表題	Usefulness of strain rate imaging in detecting ischemic myocardium during dobutamine stress.
掲載誌名	正式名：International journal of cardiology 略　 称：Int J Cardiol ISSNコード：01675273/18741754
巻・号・頁	102(2),pp.225-231
著者・共著者	Miyasaka Y, Haiden M, Kamihata H, Nishiue T, Iwasaka T.
発行年月	2005/07
概要	BACKGROUND: Tissue Doppler imaging-derived systolic myocardial velocity can detect subtle alterations in contractility during dobutamine stress. However, increased cardiac translation and tethering during dobutamine stress may affect measurements. METHODS: To examine the hypothesis that regional ischemic myocardium can be sensitively detected during dobutamine stress using myocardial strain rate, a new indicator of regional myocardial contraction that is independent of cardiac translation and tethering, we studied seven closed-chest pig confirmed chronic ischemic models produced by placing an ameroid constrictor on the left circumflex artery. Left ventricular short-axis tissue Doppler imaging was obtained at baseline and during dobutamine stress (10 and 30 microg/kg/min). Peak systolic myocardial velocity and peak systolic myocardial strain rate in anterior and posterior segments were derived offline at each stage. RESULTS: In peak systolic myocardial velocity and peak systolic myocardial strain rate, repeated-measures analysis of variance showed significant interaction between nonischemic and ischemic segments during dobutamine stress. Statistical significance between nonischemic and ischemic segments was reached at baseline, 10 microg/kg/min dobutamine, and 30 microg/kg/min dobutamine in peak systolic myocardial strain rate, and at 30 microg/kg/min dobutamine in peak systolic myocardial velocity. By receiver operating characteristic (ROC) analysis for predicting ischemic segments at 30 microg/kg/min dobutamine, a cutoff value of peak systolic myocardial strain rate was 4.84, with a sensitivity of 100% and a specificity of 100%. Peak systolic myocardial velocity was the less discriminating parameter (cutoff, 6.46; sensitivity, 86%; specificity, 86%). CONCLUSIONS: Myocardial strain rate imaging might represent an accurate parameter for clinical recognition of regional ischemic myocardium during dobutamine stress echocardiography.
文献番号	15982489