Localization of Post-Infarction Myocardial Ischemia by 201T1 Emission Computed Tomography

SummaryIn 41 patients with a history of a single myocardial infarction, the location of myocardial ischemia was studied by 201T1 emission computed tomography immediately and 3 h after intravenous dipyridamole. Distant ischemia was distinguished from periinfarctional ischemia by the presence of transient thallium defects in, or slow thallium washout from, myocardium not supplied by the infarct-related coronary artery. Distant ischemia occurred in 13 patients and was always accompanied by peri-infarctional ischemia. Peri-infarctional ischemia without distant ischemia was observed in 15 patients. The occurrence of distant ischemia was found to be dependent on the severity of stenosis in non-infarct coronary vessels. Twelve (86%) of 14 patients with non-infarct stenosis of 75% or greater had distant ischemia, but only 1 (4%) of 27 patients with non-infarct stenosis of less than 75%. In the presence of distant ischemia, peri-infarctional ischemia was in 11 patients (85%) associated with collaterals supplying the infarct zone, whereas in 13 (87%) of the patients with peri-infarctional ischemia only, incomplete obstruction of the infarct vessel was observed. It is concluded that, by the distinction between peri-infarctional and distant is-chemia, the presence of significant stenosis in non-infarct vessels can be non-invasively predicted from tomographic thallium scintigraphy with dipyridamole.Dedicated to Prof. Dr. med. C. Schneider on the occasion of his 60th birthday.

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Abstract 152: Tri-Dimentional Fusion Image of Multidetector 64-Slice-Computed Tomography and Single-Photon Emission Computed Tomography enables us to Evaluate Complicated Hemodynamics in Patients with Coronary Artery Lesions after Kawasaki Disease

Circulation ◽

10.1161/circ.131.suppl_2.152 ◽

2015 ◽

Vol 131 (suppl_2) ◽

Author(s):

Masanori Abe ◽

Makoto Watanabe ◽

Ryuji Fukazawa ◽

Shunichi Ogawa

Keyword(s):

Myocardial Infarction ◽

Computed Tomography ◽

Coronary Artery ◽

Kawasaki Disease ◽

Myocardial Ischemia ◽

Fusion Imaging ◽

Emission Computed Tomography ◽

Coronary Artery Lesions ◽

Collateral Arteries ◽

Fusion Images

Introduction: An important complication of Kawasaki disease (KD) is myocardial ischemia and acute myocardial infarction which occurs by thrombosis in coronary aneurysms and severe stenosis. The most characteristic features of coronary artery lesions (CALs) are dilation or aneurysm in acute stage and stenosis after convalescence stage. As these lesions exist singly or multiply in one coronary branch or multiple branches, coronary hemodynamics can be complicated. Ordinal methods have less potential for detection of these diseased states. Recently, Fusion imaging from coronary CT angiography (CTA) /SPECT has been thought good method for evaluation of location and severity of myocardial damages in adults. Therefore, we evaluate CALs, ischemia, and infarction after KD by Fusion imaging. Patients and Method: Seventeen patients (16 males and 1 female, age10 to 34 y) were subject. Eight patients had coronary artery bypass grafting (CABG). These tests were performed 8 to 30 years after onset of KD. CTA are performed by 64-slice-CT (LightSpeed VCT:GE Healthcare) ,and SPECT (Infinia:GE) by Tc-tetrofosmin was performed at rest and at stress after infusing adenosine. CTA and SPECT images were fused by the software (CardIQ Fusion:GE). Results and findings: In all cases, we had enough good images to detect the location of CALs and the area of ischemia. 1) Fusion images showed that no patient had significant stenotic findings at the anastomosis of bypass-graft at least several years after CABG. 2) Coronary native small branches arose from giant aneurysm were occluded by thrombosis and sub-aneurysmal lesions were infracted which were not detected by ordinal method. 3) Minimum sized myocardial ischemic lesions along to the normal visual epicardial coronary artery were detected and were suspected the existence of abnormal micro-coronary circulation caused by fibrous plaque or micro-thrombosis. 4) Collateral arteries at the stenotic and/or occluded lesions with or without ischemia were clearly detected by Fusion method. conclusion: Fusion images can visualize morphologically and functionally complicated CALs, myocardial ischemia ,and myocardial infarction after KD. Also, we can realize that peripheral coronary vessels are damaged with myocardial ischemia.

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