皿井 正義

Background and purpose: Many patients with atrial fibrillation (AF) and coronary artery stent deployment are given both antiplatelet drug and warfarin. Little information is available as to the relationship between the antithrombotic therapies in the late phase after stenting and the clinical outcomes of these patients. We examined the clinical outcomes of AF patients 12 months after coronary artery stenting. Methods: We retrospectively examined 146 patients and classified them into three groups according to the antithrombotic therapies [dual antiplatelet therapy (DAPT), single antiplatelet therapy (SAPT) plus warfarin, and DAPT plus warfarin] 12 months after stenting. We defined the primary endpoint as Thrombolysis in Myocardial Infarction major bleeding and the secondary endpoint as a composite of adverse events (CAE: all-cause death, nonfatal myocardial infarction, intracranial bleeding, and cerebral infarction). Results: During a median follow-up of 37 months, major bleeding and CAE were observed in 14(9.6%) and 46 (31.5%) patients, respectively. DAPT plus warfarin was an independent risk factor for major bleeding in a multivariate Cox hazard regression model after adjustment for age, gender, and the type of AF (hazard ratio: 4.20; 95% confidence interval: 1.13-17.27; p = 0.033). No significant clinical variables were found for CAE. Conclusions: Prolonged use of DAPT with warfarin significantly increases the risk of major bleeding in AF patients after coronary artery stenting. Individualized antithrombotic treatment is required in these patients to prevent major bleeding. (C) 2014 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

Background: The additive value of plaque characteristics determined by computed tomography angiography (CTA) in patients undergoing invasive coronary angiography (ICA) has not been established. Methods and Results: We studied 676 patients undergoing ICA and CTA within 3 months. The luminal diameter narrowing based on ICA and the presence of high risk plaque (HAP) based on CTA were assessed in all coronary artery segments except for those after or before scheduled treatment. We followed their cardiac events including cardiac death, acute coronary syndrome (ACS), and revascularization for de novo lesions months after ICA. The incidence of coronary events was higher in the segments including >25% luminal narrowing than in those without (2.94% vs. 0.31%, P<0.0001), and higher in the segments containing HAP than in those without (12.6 vs. 0.46%, P<0.0001). Greater than 25% residual luminal narrowing and the presence of HAP were identified as independent predictors of cardiac events after risk adjustment for age, gender, and history of ACS (hazard ratio [HR], 3.22; 95% confidence interval [Cl]: 1.29-10.76; P=0.0092, HR, 2.64; 95% Cl: 1.59-4.35; P=0.0002, respectively). Adding the presence of HAP to a model including age, gender, ACS history, and >25% residual stenosis improved the prediction of cardiac events. Conclusions: Assessment of coronary plaque characteristics on CTA improves the prediction of cardiac events in patients undergoing ICA.

Background: The additive value of plaque characteristics determined by computed tomography angiography (CTA) in patients undergoing invasive coronary angiography (ICA) has not been established. Methods and Results: We studied 676 patients undergoing ICA and CTA within 3 months. The luminal diameter narrowing based on ICA and the presence of high risk plaque (HAP) based on CTA were assessed in all coronary artery segments except for those after or before scheduled treatment. We followed their cardiac events including cardiac death, acute coronary syndrome (ACS), and revascularization for de novo lesions months after ICA. The incidence of coronary events was higher in the segments including >25% luminal narrowing than in those without (2.94% vs. 0.31%, P<0.0001), and higher in the segments containing HAP than in those without (12.6 vs. 0.46%, P<0.0001). Greater than 25% residual luminal narrowing and the presence of HAP were identified as independent predictors of cardiac events after risk adjustment for age, gender, and history of ACS (hazard ratio [HR], 3.22; 95% confidence interval [Cl]: 1.29-10.76; P=0.0092, HR, 2.64; 95% Cl: 1.59-4.35; P=0.0002, respectively). Adding the presence of HAP to a model including age, gender, ACS history, and >25% residual stenosis improved the prediction of cardiac events. Conclusions: Assessment of coronary plaque characteristics on CTA improves the prediction of cardiac events in patients undergoing ICA.

Objective This study aimed to compare the diagnostic value of I-123-metaiodobenzylguanidine (MIBG) myocardial scintigraphy, N-isopropyl-p[I-123] iodoamphetamine (IMP) brain perfusion single-photon emission computed tomography (SPECT), and brain magnetic resonance imaging (MRI) voxel-based morphometry (VBM) for the differentiation of dementia with Lewy bodies (DLB) and Alzheimer's disease (AD). Methods Thirty-five and 34 patients with probable DLB and probable AD, respectively, were enrolled. All patients underwent I-123-MIBG myocardial scintigraphy, I-123-IMP brain perfusion SPECT, and brain MRI. For I-123-MIBG imaging, we calculated early and delayed heart-to-mediastinum (H/M) uptake ratios. Three-dimensional stereotactic surface projections (3D-SSP) were used to analyze the results of I-123-IMP SPECT. VBM with statistical parametric mapping 8 plus diffeomorphic anatomical registration using exponentiated Lie algebra (DARTEL) was used to analyze the brain MRI data. Results The area under the receiver operating characteristic curves (AUC) for discriminating DLB and AD was highest (0.882) for the delayed H/M ratio on I-123-MIBG scintigraphy. AUC for z-score measurement in the occipital lobe was 0.818 and that for the extent of gray matter (GM) atrophy in the whole brain was 0.788. AUC for the combination of 3D-SSP and VBM analysis was 0.836. The respective sensitivities and specificities for distinguishing DLB from AD were 97.1 and 100 % for the delayed H/M ratio using I-123-MIBG scintigraphy; 88.6 and 73.5 % for the occipital lobe z-score using 3D-SSP analysis; 85.7 and 64.7 % for the extent of whole brain GM atrophy using voxel-based MRI morphometry; and 91.4 and 76.5 % for the combination of 3D-SSP analysis and VBM. Conclusions I-123-MIBG myocardial scintigraphy was superior to brain perfusion SPECT and brain MRI using an advanced statistical technique to differentiate DLB and AD.

Background: The role of combined evaluation of myocardial perfusion imaging (MPI; by single-photon emission computed tomography) and computed tomography angiography (CTA) for risk stratification of coronary artery disease was evaluated. For CTA, the extent of luminal stenosis, and also the features of high-risk plaques (HRP, including positive remodeling and low attenuation) were evaluated. Methods and Results: A total of 304 patients (65 +/- 11 years, male 72%, median follow-up: 24 months) who underwent CTA and MPI were enrolled in the study. Summed stress scores and summed difference scores (SDS) for MPI, stenosis, and HRP were evaluated, and event rates were compared. Cardiac events were defined as acute coronary event including cardiac death or non-fatal acute myocardial infarction, and unstable angina requiring revascularization. Of 304 patients, 51 (16.8%) underwent early revascularization. In the remaining 253 patients, an event occurred in 11 (4.3%). HRP (hazard ratio [HR], 4.75, P=0.00171) and stenosis (+) with SDS >0 (HR, 4.58, P=0.0461) were). HRP (hazard ratio [HR], 4.75, P=0.00171) and stenosis (+) with SDS >0 (HR, 4.58, P=0.0461) were significant independent predictors of cardiac event. The event rate for stenosis (+) with SDS >0 was significantly higher than others (log-rank P=0.0490). The event rates were significantly different between HRP(+) and HRP(-) (16.1% vs. 2.7%, log-rank P=0.0013). Conclusions: HRP on CTA was an independent predictor of acute coronary events, as was stenosis (+) with SDS >0, and HRP had increased prognostic value over stenosis and abnormal MPI findings. (Circ J 2013; 77: 411-417)

INTRODUCTION Myocardial scintigraphy with I-123-15-(p-iodophenyl)-3-methyl pentadecanoic acid (I-123-BMIPP) is used to evaluate impaired fatty acid metabolism. B-type natriuretic peptide (BNP), which is secreted by the ventricular myocardium on stretching and/or pressure overload, is a useful cardiac biomarker. This study aimed to evaluate the usefulness of I-123-BMIPP imaging and serum BNP levels in patients with heart failure (HF). METHODS 113 patients with HF were enrolled. There were 68 patients with ischaemic heart disease (IHD) and 22 with overt HF. Cardiac scintigraphy was performed 7 +/- 3 days after admission, and heart-to-mediastinum (H/M) count ratios on early and delayed images and washout rates (WR) of I-123-BMIPP were recorded. Serum BNP levels were recorded on the day of I-123-BMIPP imaging. The ejection fraction (EF) was calculated just before cardiac scintigraphy using conventional echocardiography. RESULTS The mean BNP level and EF were 282 pg/mL and 47%, respectively, with significant correlation between them. The mean H/M count ratios on early and delayed images were 2.29 and 1.93, respectively, showing significant positive correlations with EF (r = 0.31, p = 0.0006). The WR was significantly correlated with EF (r = -0.36, p < 0.0001) and BNP levels (r = 0.33, p = 0.003), and mean WR was significantly higher in patients with overt HF compared to those without (p < 0.001). Patients with IHD had significantly higher EFs than those with non-IHD (p = 0.03). CONCLUSION The evaluation of impaired myocardial metabolism using I-123-BMIPP scintigraphy and serum BNP levels appears to be useful for the evaluation of severity of HF.

Background: The differences in the coronary plaque characteristics between patients with mild chronic kidney disease (CKD) (estimated glomerular filtration rate [eGFR] 30-59 ml . min(-1) . 1.73 m(-2)) and those without CKD (eGFR >= 60) by 320-row area detector computed tomography (CT) have not been studied. Methods and Results: We enrolled 487 patients undergoing coronary CT angiography with suspected stable coronary artery disease (mean age: 66.6 +/- 10.8 years, 131 with mild CKD) and analyzed 6,352 segments. All coronary plaques were characterized for the presence of vessel remodeling, plaque consistency and the disposition of coronary calcification, and a plaque with positive vessel remodeling and/or low-attenuation was defined as high risk. The number of diseased segments per patient was higher in mild CKD patients than in those without CKD (4.61 +/- 3.83 vs. 2.95 +/- 3.11, P<0.0001). The prevalence of severe stenosis (>= 70% luminal diameter) was significantly higher in cases of mild CKD than in no CKD (35.1% vs. 19.4%, P=0.0003), but there was no significant difference in the prevalence of high-risk plaque (13.0% vs. 9.8%, P=0.3189). Conclusions: The severity of coronary artery stenosis was higher in the patients with mild CKD, though there was no significant difference in the prevalence of high-risk plaque. We suggest that the high risk of coronary events in patients with CKD is related to the severity of stenosis rather than to the characteristics of plaque. (Circ J 2012; 76: 1436-1441)

I-123-beta-methyl-iodophenyl pentadecanoic acid (BMIPP) and Tc-99m-Tetrofosmin (TF) mismatch designated as stunned myocardium having both systolic and diastolic components. The degree of mismatch might reflect subsequent functional improvement, and this study was designed to unravel the impact of mismatched defect score (MMDS) on recovery of both systolic and diastolic function following acute myocardial infarction (AMI). Forty patients with recent AMI were recruited, and all of them underwent emergency percutaneous coronary intervention. Echocardiography and BMIPP and TF cardiac scintigraphy were performed on 7 +/- A 3 days of admission. Follow up echocardiography was performed after 3 months. MMDS were compared with the systolic [ejection fraction (EF) and wall motion score index (WMSI)] and diastolic [peak velocity of early diastolic filling of mitral inflow/peak early diastolic velocity of the mitral annulus(E/E') and left atrial volume index(LAVI)] parameters. BMIPP defect score was significantly higher than the TF defect score and there was a strong positive correlation between them (r = 0.90, P < 0.00001). Thirty-two (80%) patients showed mismatched defect and rest 8(20%) showed matched defect. Of 32 patients 24(75%), 22(69%), 19(59%), and 20(62.5%) showed improved EF, WMSI, E/E' and LAVI respectively. Conversely out of 8 only 2(25%), 1(12.5%), and 2(25%) patients showed improvement of EF, WMSI and LAVI, respectively. E/E' was not improved in patients with matched defect. MMDS were significantly correlated with the improvement of EF (r = -0.46, P = 0.002), WMSI (r = 0.41, P = 0.007), E/E' (r = 0.56, P < 0.0002), and LAVI (r = 0.44, P = 0.004). Mismatched defect score could predict the approximate amount of viable dysfunctional myocardium, and the degree of mismatch showed a significant correlation with the improvement of both systolic and diastolic function.

The optimal cardiac phases for coronary CT angiography (CTA) are end-systole and mid-diastole, in which cardiac movement is slow. In conventional methods, these cardiac phases are determined by visual selection. We have compared the images in the optimal cardiac phases that were selected by the conventional method and cardiac-phase search software (Phase Navi), and examined the clinical usefulness of Phase Navi in patients with atrial fibrillation. The subjects were 38 patients (regular rhythm: 20, atrial fibrillation: 18). The continuity scores of patients with regular rhythm (Phase Navi, conventional methods) were 2.4±0.3–2.5±0.3 in end-systole and 2.4±0.5–2.4±0.4 in mid-diastole. The scores of patients with atrial fibrillation (Phase Navi, conventional methods) were 2.3±0.4–2.3±0.4 in end-systole, and 2.2±0.5–2.1±0.6 in mid-diastole. Because the continuity scores of the optimal images from Phase Navi were similar to those from the conventional method, Phase Navi had clinical usefulness in patients with atrial fibrillation.

Objectives The purpose of this study was to evaluate the role of caspase inhibitors on acute resolution of apoptosis in atherosclerotic lesions as evaluated by imaging with annexin AS. Background Extensive apoptosis of macrophages has been reported at the site of plaque rupture in patients dying of acute coronary syndrome. Methods Of 31 New Zealand White atherosclerotic rabbits, 6 received broad caspase, 3 received caspase-1, 3 received caspase-3, 3 received caspase-8, and 4 received caspase-9 inhibitors; 12 animals did not receive any caspase inhibitors (treatment control group). Six unmanipulated rabbits were used for comparison (disease control group). Technetium-99m-labeled annexin A5 was used for imaging atherosclerotic lesions; 6 of the 12 uninhibited atherosclerotic rabbits received Tc-99m-labeled mutant annexin A5 (radiotracer control group). Gamma images were obtained, and quantitative radiotracer uptake was compared with pathologic findings. Results Atherosclerotic lesions were best visible in untreated atherosclerotic rabbits. Quantitative annexin uptake, defined as the percent of injected dose per g of abdominal aorta tissue, was significantly higher in untreated atherosclerotic animals (mean +/- SD = 0.0515 +/- 0.0099) compared with the normal rabbits (0.0065 +/- 0.0008; p < 0.0001) or atherosclerotic rabbits receiving mutant annexin (0.014 +/- 0.0024; p < 0.0001). Among all caspase inhibitor-treated rabbits, uptake was 39% lower (0.0314 +/- 0.0151) than in untreated atherosclerotic animals (p < 0.01). Uptake was also significantly lower in rabbits receiving broad caspase (0.0206 +/- 0.0058; p < 0.0001) or caspase-1, -3, or -9 (0.0272 +/- 0.0088, p < 0.01; 0.0286 +/- 0.0095, p < 0.01; 0.0300 +/- 0.0021, p < 0.01, respectively) inhibitors. Caspase-8 inhibitor did not affect apoptosis (0.0618 +/- 0.0047; p = NS). Upon histologic characterization, a substantial decrease in macrophage apoptosis was observed in caspase-inhibited animals. Conclusions Molecular imaging, using radiolabeled annexin AS, allows the detection of acute resolution of apoptosis as a result of caspase inhibition in experimental atherosclerosis. If proven clinically, this may allow development of novel intervention strategies in acute vascular events.

Moyamoya disease is a vascular disease of unknown aetiology characterized by chronic progressive stenosis leading to occlusion of the supraclinoid internal carotid arteries and the proximal anterior and middle cerebral arteries along with abundant collateral vessel formation. Clinically the disease manifests with features of cerebral ischaemia including recurrent TIA's, headache, seizures or motor deficits. Characteristic angiographic features on MR angiography and conventional angiography confirm diagnosis. However, as the presence of complete arterial occlusion on angiography does not reliably predict haemodynamic impairment, single photon emission computed tomography (SPECT) is indicated for quantitative assessment of regional cerebral blood flow. SPECT is thus employed to detect regional perfusion instability prior to treatment and to determine the extent of improvement of functional perfusion after treatment. Affected patients with recurrent or progressive cerebral ischemic episodes and haemodynamic deficits SPECT findings require surgical management aimed at improving blood supply to the hypoperfused ischaemic cortical regions. The most commonly suggested revascularization procedure for children is encephaloduroarteriosynangiosis (EDAS). We describe an illustrative case report of 7-year-old boy who presented with sudden-onset of left sided herniparesis. Findings on CT, MRI and SPECT were consistent with a diagnosis of moyamoya disease with acute cerebral infarction. The boy underwent encephaloduroarteriosynangiosis twice with good outcome. Motor power in his left extremities improved from grade I to 3 without cognitive deficit. Postoperative MRI confirmed vascular patency while SPECT showed satisfactory cerebral perfusion consistent with his clinical outcome. We thus conclude that MRI and SPECT are invaluable tools in pre and postoperative evaluation of patients with moyamoya disease.

Background Restenosis still occurs, even with the sirolimus-eluting stent (SES), and the precise mechanisms and the impact of stent fracture on restensosis have not yet been elucidated. Methods and Results Intravascular ultrasound (IVUS)-guided SES implantation was performed in 184 lesions in 151 patients with stable and unstable angina. Serial (pre-, post- and follow-up) quantitative coronary angiography analysis was obtained in 169 lesions in 138 patients (angiographic follow-up rate: 91%) and 12-month clinical follow-up was done in all patients. Restenosis occurred in 13 (7.7%) of 169 lesions. Stent fracture occurred in 4 (2.4%) of 169 lesions at follow-up. Of the 13 restenotic lesions, 8 had intimal hyperplasia, 4 had stent fracture, and 1 had late stent thrombosis at 7 months. Although multivariate logistic regression analysis revealed that minimal lumen area (min-LA) post (p=0.027), total stent length (p=0.003) and diabetes (p=0.032) were significant independent predictors of restenosis, univariate analysis showed that stent fracture was more common in the restenosis than in the non-restenosis groups (p=0.001). Conclusions Although min-LA post by IVUS, total stent length by QCA and diabetes are independent predictors for angiographic restenosis, stent fracture occurred in 4 lesions (2.4%) and all of them resulted in restenosis (31% of the restenosis). The impact of stent fracture and its potential role in the development of restenosis deserves further study.

We evaluated the diagnostic usefulness of combination studies with a statistical mapping method in N-isopropyl-p-I-123-iodoamphetamine (I-123-IMP) brain perfusion SPECT, cardiac sympathetic nerve function by I-123-metaiodobenzylguanidine (I-123-MIBG), and myocardial function by electrocardiographically gated Tc-99m-sestamibi (Tc-99m-MIBI) SPECT for patients with probable or possible dementia with Lewy bodies (DLB). Methods: Twelve patients with probable DLB (7 male, 5 female; mean age +/- SID, 72.3 +/- 5.63 y; range, 65-82 y) and 9 patients with possible DLB (3 male, 6 female; mean age +/- SID, 73.1 +/- 9.23 y; range, 59-88 y) were enrolled in this study. I-123-IMP SPECT images were analyzed with 3-dimensional stereotactic surface projections (3D-SSP) and the severity of ischemia was classified objectively using quantitatively analytic and display software; stereotactic extraction estimation (SEE) methods were compared with a normal database. In addition, we evaluated I-123-MIBG heart-to-mediastinum (H/M) uptake ratios. Moreover, we performed 99mTc-MIBI SPECT to evaluate myocardial perfusion and the left ventricular ejection fraction (LVEF) compared with a normal database. Results: 3D-SSP images of group comparison with healthy control subjects showed significantly decreased perfusion in the parietotemporal, occipital cortex, posterior cingulated, and precuneus regions in the probable DLB group but no significant reduction in the possible DLB group. Mean H/M ratios in the probable DLB group were significantly lower than those of the possible DLB group and the control group, respectively. Ten of 12 patients (83.3%) with probable DLB and 1 of 9 patients (11.1%) with possible DLB showed severe reduction in the bilateral occipital lobe and also a low I-123-MIBG uptake. One patient (8.3%) with probable DLB and 2 patients (22.2%) with possible DLB showed no bilateral occipital hypoperfusion but showed low I-123-MIBG uptake. One patient (8.3%) with probable DLB and 6 patients (66.7%) with possible DLB showed no occipital hypoperfusion and normal I-123-MIBG uptake. 99mTc-MIBI gated SPECT did not indicate any wall motion abnormality in any subjects. Conclusion: These results suggest that combined examination of cerebral blood flow with 3D-SSP and SEE analysis, and cardiac sympathetic nerve function with I-123-MIBG, would be a useful supporting diagnostic method in patients with DLB-particularly, in possible DLB and when cerebral blood flow does not indicate occipital hypoperfusion.

Objectives To evaluate the feasibility of noninvasive assessment of the characteristics of disrupted atherosclerotic plaques, the authors interrogated the culprit lesions in acute coronary syndromes (ACS) by multislice computed tomography (CT). Background Disrupted atherosclerotic plaques responsible for ACS histopathologically demonstrate large lipid cores and positive vascular remodeling. It is expected that plaques vulnerable to rupture should bear similar imaging signatures by CT. Methods Either 0.5-mm X 16-slice or 64-slice CT was performed in 38 patients with ACS and compared with 33 patients with stable angina pectoris (SAP) before percutaneous coronary intervention. The coronary plaques in ACS and SAP were evaluated for the CT plaque characteristics, including vessel remodeling, consistency of noncalcified plaque (NCP < 30 HU or 30 HU < NCP < 150 HU), and spotty or large calcification. Results In the CT profile of culprit ACS and SAP lesions, the frequency of 30 HU < NCP < 150 HU (100% vs. 100%, p NS) was not different, and large calcification (22% vs. 55%, p = 0.004) was significantly more frequent in the stable lesions. Positive remodeling (87% vs. 12%, p < 0.0001), NCP < 30 HU (79% vs. 9%, p < 0.0001), and spotty calcification (63% vs. 21%, p = 0.0005) were significantly more frequent in the ACS lesions. Presence of all 3 (i.e., positive remodeling, NCP < 30 HU, and spotty calcification) showed a high positive predictive value, and absence of all 3 showed a high negative predictive value for the culprit plaques associated with ACS. Conclusions The CT characteristics of plaques associated with ACS include positive vascular remodeling, low plaque density, and spotty calcification. It is logical to presume that plaques vulnerable to rupture harbor similar characteristics. (J Am Coll Cardiol 2007;50:319-26) (c) 2007 by the American College of Cardiology Foundation.

Background It has been proposed that 0.5-mm-slice multislice computed tomography (MSCT) is a noninvasive tool for the detection of atherosclerotic plaque, but the validity of such an assessinent has not been demonstrated by an invasive investigation. The present study was performed to compare the 0.5-mm-slice NISCT density of plaques with intravascular ultrasound (IVUS) findings. Methods and Results Atherosclerotic plaques were characterized in 37 consecutive patients undergoing percutaneous interventions. Based on the IVUS echogenecity, the plaques were classified as soft (n= 18), fibrous (n= 40) or calcified (n=40). In these 98 plaques, 0.5-mm-slice MSCT plaque density was calculated in 443 regions-of-interest, including 331 lesional foci and 112 luminal cross-sections, and represented as Hounsfield units (HU). MSCT density of the 3 types of plaque was 11 +/- 12 HU, 78 +/- 21 HU, and 516 +/- 198 HU respectively. Computed tomography density of the (contrast-filled) lumen was 258 +/- 43HU. There were statistically highly significant differences in the densitometric characteristics among the 4 groups (soft, fibrous, calcified plaque and lumen) by nonparametric Kruskal-Wallis test (p < 0.0001). Conclusions The IVUS-based coronary plaque configuration can be accurately identified by 0.5-mm slice MSCT. Noninvasive assessment of plaque characterization will ensure emphasis on the vessel wall beyond the vascular lumen.

Transgenic mice such as apolipoprotein E-deficient (apoE(-/-)) and low-density-lipoprotein receptor-deficient (LDLR-/-) mice exhibit hypercholesterolemia and develop complex atherosclerotic lesions similar to those seen in humans. Radiolabeled annexin A5 has been successfully used to noninvasively image experimental and clinical atherosclerotic disease. We evaluated the feasibility of annexin A5 imaging in transgenic apoE(-/-) and LDLR-/- mice with or without a cholesterol diet. Methods: Thirty-three mice (mean age, 62 +/- 0.9 wk old) were used. Of these 33 mice, apoE(-/-) mice with the cholesterol diet for 4 mo (n = 5) and without the cholesterol diet (n = 8) and LDLR-/- mice with the cholesterol diet for 6 mo (n = 7) and without the cholesterol diet (n = 7) were compared with 6 normal wild-type (C57BL/6) mice with the same genetic background. Tc-99m-annexin A5 was injected in 31 animals for noninvasive imaging using micro-SPECT/CT. After in vivo micro-SPECT/CT, aortas were explanted to acquire ex vivo images and calculate the percentage injected dose per gram (%ID/g) annexin uptake, followed by histologic and immunohistochemical characterization. For the evaluation of precise target localization, biotinylated annexin A5 was injected in the remaining 2 normally fed apoE(-/-) mice. Results: Aortic lesions were clearly visualized noninvasively by micro-SPECT and aorta calcification was detectable by micro-CT. The quantitative uptake of annexin A5 was highest in the cholesterol-fed apoE-/- (0.88 +/- 0.27 %ID/g) mice, followed by the normal chow-fed apoE(-/-) (0.60 +/- 0.16 %ID/g), the cholesterol-fed LDLR-/- (0.59 +/- 0.14 %ID/g), the chow-fed LDLR-/- (0.40 +/- 0.31 %ID/g), and the control (0.15 +/- 0.05 %ID/g) mice. The histologic extent of atherosclerosis paralleled radiotracer uptake, and immunohistochemical studies revealed a significant correlation between radiotracer uptake and both macrophage infiltration and the extent of apoptosis. Intravenously injected biotinylated annexin A5 localized in apoptotic and nonapoptotic macrophages. Conclusion: This study demonstrates the feasibility of noninvasive imaging of atherosclerosis with radiolabeled annexin A5 in transgenic mouse models of human atherosclerosis.

Although apoptosis within atherosclerotic plaques is associated with plaque vulnerability and rupture, the role of inhibition of the apoptotic process is not clear. We evaluated the impact of dietary modification and statin therapy (measures known to favorably influence outcomes in coronary disease) on the incidence of apoptosis in experimental atherosclerotic lesions. Methods: A total of 30 animals were studied; 1 group of 6 animals served as the controls (group 1), and the remaining 24 animals were subjected to balloon de-endothelialization of the abdominal aorta and a high-cholesterol diet. These atherosclerotic animals were randomized as follows: high-cholesterol diet for 4 mo (n = 6; untreated atherosclerotic group [group 2]), high-cholesterol diet for 3 mo and normal chow diet for 1 mo (n = 6; diet withdrawal group [group 3]), and high-cholesterol diet for 4 mo and simvastatin orally every day of the last month (n = 6; statin therapy group [group 4]). Tc-99m-Annexin A5 was used for noninvasive detection of apoptosis in groups 1-4. The remaining 6 rabbits on a high-cholesterol diet for 4 mo were studied with radiolabeled mutant annexin A5 (n = 6; nonspecific control group [group 51). Quantitative annexin A5 uptake in the abdominal aorta was determined and compared with the histologic and immunohistochemical characteristics of the atherosclerotic lesions. Results: Maximum annexin A5 uptake (mean +/- SD, 0.051 +/- 0.009 percentage injected dose per gram [%ID/g] of tissue) was observed in the untreated atherosclerotic animals. The uptake was substantially reduced in the diet withdrawal (0.03 +/- 0.006 %ID/g; P < 0.0001) and statin therapy (0.03 +/- 0.006 %ID/g; P < 0.0001) groups. The plaques in the untreated high-cholesterol group demonstrated advanced atherosclerotic lesions. On the other hand, the diet withdrawal and statin therapy groups showed histologic characteristics of stabilization, including the resolution of macrophage infiltration and an increase in smooth muscle cell content. There was a marked reduction in the apoptosis of macrophages. No significant uptake of annexin A5 or mutant annexin A5 was seen in rabbits on the normal chow diet or atherosclerotic rabbits, respectively. Conclusion: Dietary modification and statin therapy in atherosclerosis lead to a reduction in apoptosis and contribute to plaque stabilization. It can be hypothesized that a reduction in apoptosis is a favorable process in atherosclerotic disease.

Background Multislice computed tomography coronary angiography (CTCA) is reconstructed by ECG gating and consequently it is difficult to obtain coronary artery images from patients with arrhythmias, such as atrial fibrillation (AF), by the conventional method. Methods and Results Eleven patients with AF (9 males, 2 females; mean age: 62.5 years) underwent CTCA using a slice thickness of 0.5 mm, gantry rotation of 0.4 or 0.5 s/rot and pitch of 3.2-4.0. A segmented reconstruction method was used to construct CTCA images at the conventional relative 70-75% (mid-diastolic phase) and 30-35% (end-systolic phase) of the R-R interval and furthermore, the absolute mid-diastolic phase and end-systolic phase from the R wave. Three investigators, who were unaware of the coronary angiography results, independently evaluated the curved multiplanar reconstruction (MPR) images. In both the relative and absolute phase reconstruction, there were motion artifacts in the mid-diastolic than in the end-systolic phase. The absolute phase images had less motion artifacts than the conventional relative phase images. Optimal curved MPR images were obtained in the absolute end-systolic phase. The quality and motion artifacts of those optimal images from AF patients were similar to those from patients in sinus rhythm. Conclusion The absolute end-systolic phase is the best time to get optimal CTCA images in AF patients.

Background Multislice helical computed tomography ( MSCT) has been used to depict coronary anatomy noninvasively, and proved useful for evaluating ventricular function. The aim of our study was to assess the accuracy of ventricular volume as measured by MSCT. Methods Fourteen human left ventricular (LV) and 15 right ventricular ( RV) casts were scanned by MSCT. A series of LV and RV short-axis images were reconstructed later with slice thickness of 2.0 mm, 3.5 mm, 5.0 mm, 7.0 mm, and 10.0 mm. Ventricular volume was calculated by the multislice tomographic Simpson's method. True LV and RV cast volumes were determined by water displacement. Results Both calculated LV and RV volumes correlated highly with the corresponding true volumes (all r > 0.95, P < 0.01). But with slice thickness from 2.0 mm to 10.0 mm, MSCT scanning overestimated the corresponding true volume by (3.21 +/- 5. 95) ml to (12.58 +/- 8. 56) ml for LV and (10.22 +/- 8.45) ml to (23.91 +/- 12.24) ml for RV ( all P < 0.01). There was a very high correlation between the overestimation and the selected slice thickness for both LV and RV volume measurements ( r = 0.998 and 0.996, P < 0.01, respectively). However, when slice thickness was reduced to 5.0 mm, the overestimation for both LV and RV volume measurements became nonsignificant for slice thickness from 2.0 mm to 5.0 mm. Conclusions Both LV and RV volumes can be accurately estimated by MSCT. Thinner slice has more accurate calculated volume. However, 5.0 mm slice thickness is thin enough for an accurate measurement of LV or RV volume.

Background: The complexity of right ventricular (RV) shape makes it more difficult for measuring its volume. However, the short-axis view of the right ventricle usually is crescent and might be assumed as half of a circle. This hypothesis can be applied to calculate RV volume by using the single-plane Simpson's method, but the final RV volume should be about half of the original calculated value. The aim of this study was to test the accuracy of RV volume measurement based on this new assumption in human RV casts. Methods: Fifteen human RV casts were scanned with multislice helical CT and RV sagittal image that corresponds to right anterior oblique view were reconstructed. Single-plane Simpson's method was used to calculate RV volumes. The calculated RV volume was defined as the original calculated value divided by 2. The true RV cast volume was determined by water displacement. Results: The true RV volume was 64.23 +/- 24.51 ml; the calculated volume was 53.18 +/- 26.22 ml. The calculated RV correlated closely with true volume with a regression equation of RV actual volume= 21.04 0.406 x RV calculated volume (r= 0.869, P< 0.001), but significantly underestimated the actual volume by 11.05 +/- 13.09 ml (P < 0.006). Conclusion: Right ventricular volume could be calculated with single-plane Simpson's method based on the new proposed half-circle model. (C) 2003 Elsevier Ireland Ltd. All rights reserved.

To study whether thrombolytic therapy affects Gd-DTPA-enhanced pattern and whether its pattern indicates myocardial viability, Gd-DTPA-enhanced magnetic resonance imaging (MRI) was performed in 43 patients with reperfused acute myocardial infarction 14.8 ± 5.0 days after onset with breathhold scanning on a 1.5T whole body system. The hypoenhanced area at 90 sec after contrast injection was defined as a perfusion defect (PD). Patients were divided into PD(+) and PD(-) groups. The PD was detected in 77.8% of patients treated with direct percutaneous transluminal coronary angioplasty (PTCA) and in 28.6% of patients treated by thrombolytic therapy with or without PTCA in the thrombolysis in myocardial infarction grade 3 group (p &gt 0.05). The myocardial wall was divided into seven segments based on the American Heart Association committee report. Wall motion of each segment was classified by one of six patterns (wall motion score [WMS]: dyskinesis, -1 akinesis, 0 severe hypokinesis, 1 hypokinesis, 2 slight hypokinesis, 3 normal, 4). By echocardiography, the average WMS and ejection fraction were similar between the PD(+) group and the PD(-) group on admission. Those parameters were significantly worse in the PD(+) group than in PD(-) group 1 month after onset. The change in WMS was significantly lower in the PD(+) group than in the PD(-) group. The number of patients and segments with more than two grades of improvement of WMS in the PD(+) group was significantly lower than that in the PD(-) group. Angiographically, left ventricular ejection fraction and WMS of the PD(+) group were significantly lower than those of the PD(-) group 3 months later. PDs were detected significantly less frequently in patients treated with thrombolytic therapy, suggesting that microvascular embolization related to formation of the no-reflow phenomenon.

Objective: To determine the usefulness of vectorcardiography (VCG) in assessing myocardial infarct size. Methods: The correlation of spatial and scalar parameters of VCG with the percent defect volume (% DV) of thallium myocardial single photon emission computed tomography (SPECT) was investigated in 63 patients with first-onset myocardial infarction (MI). VCG parameters included: (1) spatial parameters: magnitude, azimuth and elevation of the maximal vector, vectors at 20 ms and 30 ms, and (2) scalar parameters: amplitudes of 20 ms and 30 ms vectors at X, Y, and Z scalar leads abbreviated as X20, Y20, Z20, X30, Y30 and Z30, respectively. Results: For anteroseptal MI, the azimuth of 30 ms vector and Z20 showed a significant correlation with % DV (r=0.572, P&lt 0.05 and r=0.832, P&lt 0.001) while in anteroseptal MI with involvement of lateral wall, the azimuth of 30 ms vector and X30 were correlated with %DV significantly (r=0.775, and 4=0.780, P&lt 0.01). For inferior and inferoposterior MI, the elevation of 30 ms vector and Y30 were correlated well with %DV (r=0.871, P&lt 0.01, r=0.928, P&lt 0.001 for inferior MI and r=0.678, P&lt 0.01, r=0.760, P&lt 0.001 for inferoposterior MI). Conclusion: VCG parameters, especially scalar parameters, can be used to evaluate myocardial infarct size easily and non-invasively with remarkable accuracy.

A 41-year-old man visited our hospital with the complaint of palpitation by atrial flutter. He was finally diagnosed as total anomalous pulmonary vein drainage by helical computed tomography (CT). This case is very unusual due to the lack of symptoms until the age of 41. The absence of pulmonary artery stenosis, and the presence of atrial septal defect providing sufficient right to left shunt flow to maintain the output of left ventricle are some of the reasons to explain the lack of symptoms and very slight impact on daily life. Helical CT, in particular 3-dimensional imaging, is very useful in diagnosing complicated cardiovascular deformation as in this case.