Changes in Internal Thoracic Artery Blood Flow According to the Degree of Stenosis of the Anterior Descending Branch of the Left Coronary Artery.

PURPOSE: Computational fluid dynamics has enabled the evaluation of coronary flow reserve. The purpose of this study was to clarify the hemodynamic variation and reserve potential of the left internal thoracic artery (LITA). METHODS: Four patients were selected on the basis of various native coronary stenosis patterns and graft design. The wall shear stress and oscillatory shear index were measured, and one patient was selected. Next, we created three hypothetical lesions with 75%, 90%, and 99% stenosis in front of the graft anastomosis, and compared the changes in LITA blood flow and coronary flow distribution. RESULTS: In the 75% to 90% stenosis model, blood flow was significantly higher in the native coronary flow proximal to the coronary artery bypass anastomosis regardless of time phase. In the 99% stenosis model, blood flow from the LITA was significantly dominant compared to native coronary flow at the proximal site of anastomosis. The range of LITA flow variability was the largest at 99% stenosis, with a difference of 70 ml/min. CONCLUSION: The 99% stenosis model showed the highest LITA flow. The range of LITA flow variability is large, suggesting that it may vary according to the rate of native coronary stenosis.

Association of the extent of myocardial ischemia with outcomes in patients with suspected coronary artery disease in Japan.

BACKGROUND: There is an ongoing controversy regarding the necessity of single-photon emission computed tomography (SPECT) for patients with ischemic heart diseases after the publication of the results of the ISCHEMIA trial. We aimed to evaluate the association of the extent of myocardial ischemia with outcomes in patients with suspected coronary artery disease in Japan. METHODS: From the data of 2780 patients with stable angina who were enrolled prospectively between January 2006 and March 2008 in Japan and had undergone physician-referred non-invasive imaging tests (Japanese Coronary-Angiography or Myocardial Imaging for Angina Pectoris Study), 1205 patients managed with SPECT were stratified by 10 % myocardial ischemia. Major adverse cardiac events (MACEs), including death, myocardial infarction, hospitalization for heart failure, and late revascularization, were followed-up for 1 year. RESULTS: Patients with ≥10 % myocardial ischemia (n = 173) were less likely to be women than patients with <10 % myocardial ischemia (n = 1032) and had a significantly higher 1-year cumulative incidence of MACEs (6.9 % vs. 1.8 %, p < 0.0001). After adjusting for confounders, the risk of ≥10 % myocardial ischemia relative to <10 % myocardial ischemia for MACEs remained significant [adjusted hazard ratio (95 % confidence interval), 2.40 (1.09-5.26), p = 0.029]. After adjusting including treatments, the risk of MACEs became insignificant between the ≥10 % myocardial ischemia group and the <10 % myocardial ischemia group [adjusted hazard ratio (95 % confidence interval), 1.04 (0.45-2.45), p = 0.92]. CONCLUSION: The presence of ≥10 % myocardial ischemia at diagnosis was significantly associated with the 1-year risk for MACEs in Japanese patients with suspected coronary artery disease.

The characteristics of Japanese guidelines on diagnosis and treatment of cardiac sarcoidosis compared with the previous guidelines.

Sarcoidosis in Japanese sarcoidosis is characterized by a high prevalence of cardiac involvement. In this regard, cardiac sarcoidosis (CS) continues to be an important focus of study among physicians caring for sarcoidosis in Japan. The Japanese Ministry of Health, Labor and Welfare (MHLW) and Japan Society of Sarcoidosis and other Granulomatous Disorders (JSSOG) have published clinical guidelines aiming to assist clinical practices. Recently, the Japanese Circulation Society (JCS) has published new clinical guidelines for the diagnosis and treatment of CS that contain several new insights compared to previously published guidelines in Japan and other countries.

T2-weighted short-tau-inversion-recovery imaging reflects disease activity of cardiac sarcoidosis.

OBJECTIVE: We investigated the diagnostic performance of semi-quantitative hyperintensity on T2-weighted short-tau-inversion-recovery black-blood (T2W-STIR-BB) images in identifying active cardiac sarcoidosis (CS) in patients, and compared it with that of 18F-fluoro-2-deoxyglucose positron emission tomography (FDG-PET). METHODS: This retrospective study included 40 steroid-naive patients (age 63.1±12.9 years, 20 men) diagnosed with CS who underwent both cardiac MRI and FDG-PET imaging. Active CS cases were defined as satisfying at least one of the following criteria for conventional indices: exacerbation of ventricular arrhythmia, newly identified advanced atrioventricular block, greater than 5% decrease in left ventricular ejection fraction on echocardiography, positive finding on gallium-scintigraphy or elevated levels of sarcoidosis-related serum biomarkers. T2W-STIR-BB images were semi-quantitatively analysed using a myocardium-to-spleen ratio (MSR). The diagnostic performance of T2W-STIR-BB and FDG-PET imaging for detecting active CS was investigated. RESULTS: Thirty-three patients satisfied at least one criterion and were considered as having active CS. Thirty patients (75%) tested positive with T2W-STIR-BB imaging, and 25 patients (63%) tested positive with FDG-PET. The sensitivity, specificity, accuracy, and positive and negative predictive values for identifying active CS by semi-quantitative MSR on T2W-STIR-BB images were 79%, 43%, 73%, 87% and 30%, respectively. These results were statistically comparable to those of FDG-PET (70%, 71%, 70%, 92% and 33%, respectively). CONCLUSIONS: When using conventional diagnostic indices for active CS as the gold standard, T2W-STIR-BB imaging demonstrated comparable diagnostic performance to that of FDG-PET. The semi-quantitative analysis of high signal intensity on T2W-STIR-BB images using MSR was useful for detection of active CS.

High-Density Lipoprotein Cholesterol Efflux Capacity as a Novel Prognostic Surrogate for Coronary Artery Disease.

AIM: We examined the impact of baseline high-density lipoprotein cholesterol efflux capacity (CEC) on major cardiac adverse events (MACE) in patients with coronary artery disease (CAD) during a long-term secondary prevention. METHOD: CEC was measured using a cell-based efflux system in (3)[H]-cholesterol-labeled J774 macrophages in apolipoprotein B-depleted plasma between January 2011 and January 2013. Patients with CAD were divided into 2 groups as a boundary CEC value of 1: 0.19 ≤ CEC ＜1 (impaired CEC group, mean CEC of 0.76±0.16, n=136), and 1 ≤ CEC ≤ 2.08 (enhanced CEC group, 1.20±0.19, n=44). MACE, comprised the incidence of cardiac death, non-fatal myocardial infarction, and any revascularizations (RV) without restenosis approximately 1 year after vascularization, was retrospectively investigated at September 2019. Impact of enhanced CEC on MACE among 22 variables was examined by applying a Cox proportional hazard model. RESULT: The frequency of MACE in impaired CEC group (16.9%, mean observational interval of 2111±888 days) was significantly higher than that in enhanced CEC group (2.3%, 2,252±685, p=0.013), largely driven by the significantly higher RV incidence (14.0 % versus 2.3 %, p=0.032). Enhancement of CEC was the significant predictor of MACE (hazard ratio: 0.11; 95% CI: 0.013-0.879; p=0.038). CONCLUSION: A baseline CEC level of more than 1 in patients with CAD brought favorable long-term clinical outcomes, suggesting that CEC is a useful prognostic and therapeutic surrogate for secondary prevention of CAD.

Association of coronary revascularisation after physician-referred non-invasive diagnostic imaging tests with outcomes in patients with suspected coronary artery disease: a post hoc subgroup analysis.

OBJECTIVE: We aimed to evaluate the association of the prognostic impact of coronary revascularisation with physician-referred non-invasive diagnostic imaging tests (single photon emission CT (SPECT) vs coronary CT angiography) for coronary artery disease. DESIGN: A post hoc analysis of a subgroup from the patient cohort recruited for the Japanese Coronary-Angiography or Myocardial Imaging for Angina Pectoris Study. SETTING: Multiple centres in Japan. PARTICIPANTS: From the data of 2780 patients with stable angina, enrolled prospectively between January 2006 and March 2008 in Japan, who had undergone physician-referred non-invasive imaging tests, 1205 patients with SPECT as an initial strategy and 625 with CT as an initial strategy were analysed. We assessed the effect of revascularisation (within 90 days) in each diagnostic imaging stratum and the interaction between the two strata. PRIMARY AND SECONDARY OUTCOME MEASURES: Major adverse cardiac events (MACEs), including death, myocardial infarction, hospitalisation for heart failure and late revascularisation, were followed up for 1 year. The χ2 test, Student's t-test, Kaplan-Meier analysis, log-rank test and multivariable Cox proportional hazard model were used in data analysis. RESULTS: A total of 210 (17.4%) patients in the SPECT stratum and 149 (23.8%) in the CT stratum underwent revascularisation. Although in each stratum, the cumulative 1 year incidence of MACEs was significantly higher in patients who underwent revascularisation than in those who did not (SPECT stratum: 9.1 vs 1.2%, log-rank p<0.0001; CT stratum: 6.1 vs 0.8%, log-rank p=0.0001), there was no interaction between the risk of revascularisation and the imaging strata (SPECT stratum: adjusted HR (95% CI), 4.25 (1.86-9.72); CT stratum: 4.13 (1.16-14.73); interaction: p=0.97). CONCLUSION: The association of revascularisation with the outcomes of patients with suspected coronary artery disease was not different between SPECT-first and CT-first strategies in a physician-referred fashion.

Impact of renal dysfunction on the choice of diagnostic imaging, treatment strategy, and outcomes in patients with stable angina.

We investigated the interaction between the prognostic impact of a decrease in eGFR and the choice of initial diagnostic imaging modality for coronary artery disease. Out of 2878 patients who enrolled in the J-COMPASS study, 2780 patients underwent single photon emission computed tomography (SPECT), coronary computed tomography (CT) angiography, or coronary angiography (CAG) as an initial diagnostic test. After excluding patients with routine hemodialysis or lacked serum creatinine levels, 2096 patients in the non-decreased eGFR group (eGFR ≥ 60 ml/min/1.73 m2) and 557 patients in the decreased eGFR group (eGFR < 60 ml/min/1.73 m2) were analyzed in this study. Major adverse cardiac events, including death, myocardial infarction, heart failure hospitalization, and late revascularization, were followed, with a median follow-up duration of 472 days. SPECT or CAG was preferable to CT in patients in the decreased eGFR group (p < 0.0001 and p = 0.0024, respectively). There was a marginally significant interaction between the prognostic impact of a decrease in eGFR and the choice of diagnostic imaging modality (interaction-p = 0.056). A decrease in eGFR was not associated with a poor outcome in patients who underwent CT, while a decrease in eGFR was associated with poor outcomes in patients who underwent SPECT or CAG. In conclusion, the prognostic impact of a decrease in eGFR tended to be different among the initial imaging modalities.

Long-term events after physician-referred initial tests by myocardial perfusion imaging or computed tomography coronary angiography in patients with suspected coronary artery disease.

BACKGROUND: The effects of initial tests on long-term events have been unknown. PATIENTS AND METHODS: In this observational retrospective study, we analyzed the effects of initial noninvasive tests by myocardial perfusion imaging (MPI) and computed tomography angiography (CTA) on long-term major adverse cardiac events (MACEs) among patients with suspected coronary artery disease during a median follow-up of 8.1 years (interquartile range: 7.7-8.9). RESULTS: Sex difference in the rate of abnormal findings on initial tests was observed in both the MPI (female vs. male: 32.6 vs. 55.5%; P<0.0001) and CTA groups (30.6 vs. 47.9%; P<0.0001). Early revascularization in the MPI was significantly lower than that in the CTA (16 vs. 23%; P=0.0005). A total of 109 MACEs (39 of 1830 patients during the original follow-up period and 70 of 616 patients during the extended follow-up period) occurred: 77 MACEs (6.4%) in the MPI group and 32 (5.1%) in the CTA group (adjusted hazard ratio for MPI: 0.78; 95% confidence interval: 0.50-1.23; P=0.29). In the total cohort, the risk-adjusted MACE rate in the females was ∼50% of the males. CONCLUSION: The long-term MACE rates did not differ between physician-referred initial tests of MPI and CTA despite a higher frequency of early revascularization in the CTA group. In this extended cohort, female sex was associated with a lower rate of positive findings and a lower MACE rate compared with the male sex.

High-density lipoprotein cholesterol efflux capacity as a relevant predictor of atherosclerotic coronary disease.

BACKGROUND: We examined the clinical relevance of high-density lipoprotein cholesterol (HDL-C) efflux capacity from macrophage (cholesterol efflux capacity) as a predictor of atherosclerotic coronary artery disease (CAD) in comparison with that of conventional coronary and lipid risk variables in Japanese daily practice. METHODS AND RESULTS: Fasting blood sampling, including 6 routinely measured dyslipidemia-related variables, was performed at the time of coronary angiography (CAG) or multi-slice coronary computed tomography (MSCT) between January 2011 and January 2013. CAD, defined as native coronary atherosclerosis stenosis >50% by CAG or MSCT, was identified in 182 patients (CAD group), but not in 72 patients (non-CAD group). Cholesterol efflux capacity, measured using a cell-based efflux system in (3)[H]-cholesterol-labeled J774 macrophages in apolipoprotein B-depleted plasma, was significantly impaired in the CAD group compared with the non-CAD group (0.86 ± 0.26 vs. 1.02 ± 0.38; p = 0.001). After adjusting 15 patient and dyslipidemia-related variables using a propensity score matching analysis produced 55 patients in each arm, cholesterol efflux capacity in the CAD group remained to be significant compared with the non-CAD group (0.83 ± 0.24 vs. 0.97 ± 0.36; p = 0.019). Stepwise logistic regression analysis using a backward method after the baseline adjustment showed that cholesterol efflux capacity (odds ratio [OR]: 0.23; 95% confidence interval [CI]: 0.056-0.91; p = 0.037) was the single predictor of CAD, while other variables including HDL-C (p = 0.088) and apolipoprotein (apo) A-I (p = 0.681) were removed owing to those insignificance. The area under the receiver operating characteristic curve after the baseline adjustment was 0.67 (95% CI: 0.51-0.73, p = 0.048 by Hosmer-Lemeshow goodness-of-fit statistics). CONCLUSIONS: The present observational study conducted under daily clinical practice confirmed that cholesterol efflux capacity is a clinically relevant predictor of CAD among the conventional coronary risk factors and dyslipidemia-related variables.

Utility of ECG-gated MDCT to differentiate patients with ARVC/D from patients with ventricular tachyarrhythmias.

BACKGROUND: The accuracy of electrocardiogram-gated CT for diagnosing arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) is uncertain. OBJECTIVE: We propose a comprehensive system for scoring characteristic CT findings to diagnose ARVC/D and discuss its utility. METHODS: Seventy-seven patients (mean age, 43.1 years; 48 male) diagnosed with ARVC/D or with suspected ARVC/D on the basis of ventricular tachyarrhythmias underwent CT with and without contrast enhancement. We retrospectively graded characteristic CT findings (fatty tissue, bulging appearance, and dilatation of the right ventricle) as minor (1 point) or major (2 points) and then validated our scoring system's utility for diagnosing ARVC/D with the use of the modified 2010 Task Force criteria as the reference standard. RESULTS: We diagnosed 27 of 77 patients with ARVC/D (23 definite, 4 borderline), observing each CT finding more often in patients with ARVC/D than in patients without ARVC/D: fatty tissue, 74.1% versus 12.0%; bulging appearance, 74.1% versus 34.0%; and RV dilatation, 92.6% versus 44.0%. However, observation of each finding in both groups could cause false positive diagnosis. Recursive partitioning analysis showed the superiority of our CT scoring system over methods that used each CT finding and CT findings without fatty tissue for distinguishing ARVC/D and non-ARVC/D. For overall (definite and borderline) and definite ARVC/D diagnosis, sensitivities were 77.8% and 87.0%, specificities were 96.0% and 94.4%, positive predictive values were 91.3% and 87.0%, negative predictive values were 88.9% and 94.4%, and accuracies were 89.6% and 92.2%, respectively. CONCLUSIONS: Our CT scoring system showed excellent diagnostic ability and might aid differentiation of ARVC/D from ventricular tachyarrhythmias.

CT features of myocardial fat and correlation with clinical background in patients without cardiac disease.

OBJECTIVE: To evaluate the frequency and common locations of myocardial fat and its associated factors using coronary CT angiography (CCTA) in patients without cardiac disease. METHODS: Using CCTA findings for 298 consecutive patients without cardiac disease, we categorized the myocardium into nine locations, scored fat in those locations, and correlated the fat score with the thickness of the right ventricular (RV) free wall and factors including gender, age, and body mass index (BMI) as well as history of diabetes mellitus, hypertension (HT), and dyslipidemia. RESULTS: We observed myocardial fat in 68.5 % of patients, most commonly in the RV outflow tract (RVOT, 64.1 %), followed by the base (42.3 %) and middle (28.9 %) of the RV free wall, RV trabeculations (22.5 %), and the left ventricular apex (11.4 %). The RV free wall thickened significantly with increasing fat score. Dependent variables for myocardial fat were female gender (P < 0.0001), age ≥65 years (P = 0.0043), BMI ≥25 (P = 0.0050), and HT (P = 0.0139). CONCLUSION: Myocardial fat is a common finding on CCTA in patients without cardiac disease, is often observed in the RVOT, and is more frequent in female patients, those older than 65 years, those with BMI ≥25, and those with HT.

Late gadolinium enhancement in cardiac sarcoidosis: characteristic magnetic resonance findings and relationship with left ventricular function.

PURPOSE: Cardiac involvement is an important prognostic factor in sarcoidosis, and cardiovascular magnetic resonance (CMR) imaging with late gadolinium enhancement (LGE) can facilitate the identification of cardiac sarcoidosis (CS). In patients with CS, we investigated LGE characteristics and their relationship with left ventricular (LV) function to identify those characteristics unique to severely reduced LV function. We also investigated the relationship between LGE and duration of sarcoidosis. MATERIALS AND METHODS: We retrospectively evaluated 19 patients with CS diagnosed according to the 2006 revised guidelines of the Japanese Ministry of Health and Welfare who underwent CMR imaging. We analyzed LGE location using 17-segment and subsegment (subepicardial, midwall, subendocardial, and transmural) models and evaluated the relationship between the characteristics of LGE and LV ejection fraction (LVEF) and duration of sarcoidosis. RESULTS: Images of 17 of the 19 patients showed LGE most frequently in the subepicardial layer. The total number of affected segments with LGE correlated significantly with LVEF (r=-0.84, P<0.0001) and LV-diastolic volumes (r=0.88, P<0.0001). Transmural lesions were significantly more common in patients with LVEF of 35% or lower than in those with LVEF exceeding 35% (P=0.0004). All patients with LVEF of 35% or lower had both subepicardial and transmural lesions. The total number of affected segments with LGE correlated with the duration of sarcoidosis in patients with onset in an extracardiac organ (r=0.76, P=0.005). CONCLUSIONS: Demonstration of a characteristic LGE pattern and location allows diagnosis of CS, and CMR imaging with LGE aids in prediction of LV function.

Prognostic value of (123)I-betamethyl-p-iodophenyl-pentadecanoic acid single-photon emission computed tomography in diabetic patients with suspected ischemic heart disease.

BACKGROUND: Because of their high risk for cardiovascular events, we investigated the role of (123)I-betamethyl-p-iodophenyl-pentadecanoic acid (BMIPP) SPECT in evaluating the prognosis of diabetic patients with suspected coronary heart disease. METHODS AND RESULTS: We retrospectively registered 186 diabetic patients with suspected coronary heart disease, but no previous diagnosis of heart disease, who had been examined by BMIPP and thallium (TL) dual SPECT. They were followed for over 2 years. The dual SPECT images were scored to obtain summed defect scores for each SPECT image (BMDS, TLDS and mismatch score [MS]). The primary endpoint was the first incidence of all-cause cardiac events. The secondary endpoint was cardiac death. Clinical classical risk factors in addition to the stage of chronic kidney disease (CKD), as well as cardiac function, were included in the prognostic analysis. Cardiac events occurred in 39 patients, including 8 cardiac deaths. Kaplan-Meier analysis revealed significantly more frequent cardiac event rates in patients with than without MS ≥5 or BMDS ≥6 (P<0.0001). Cox hazard multivariate analysis showed that MS and CKD stage or BMIPP and CKD stage were independent predictors. Only hemodialysis was a significant prognostic indicator for cardiac death. CONCLUSIONS: BMIPP SPECT when combined with CKD stage accurately predicts cardiac events among diabetic patients with suspected ischemic heart disease.

Clinical implications of midventricular obstruction in patients with hypertrophic cardiomyopathy.

OBJECTIVES: We investigated the prevalence, clinical characteristics, and prognosis of hypertrophic cardiomyopathy (HCM) patients with midventricular obstruction (MVO). BACKGROUND: Previous descriptions of patients with MVO have been confined to case reports or small patient series, and this subgroup of HCM patients has therefore remained underrecognized. METHODS: The study population included 490 HCM patients. Left ventricular MVO was diagnosed when the peak midcavitary gradient was estimated to be ≥30 mm Hg. RESULTS: MVO was identified in 46 patients (9.4%). Patients with MVO were more likely to be symptomatic than those without. MVO was found to be an independent determinant of HCM-related death in multivariate models (hazard ratio [HR]: 2.23, p = 0.016), and this trend was especially pronounced for the combined endpoint of sudden death and potentially lethal arrhythmic events (HR: 3.19, p < 0.001). Apical aneurysm formation was identified in 28.3% of patients with MVO and strongly predicted HCM-related death (HR: 3.47, p = 0.008) and the combined endpoint of sudden death and potentially lethal arrhythmic events (HR: 5.08, p < 0.001). In addition, MVO without apical aneurysm was also identified as an independent determinant of the combined endpoint of sudden death and potentially lethal arrhythmic events (HR: 2.43, p = 0.045). CONCLUSIONS: This analysis identified MVO as an independent predictor of adverse outcomes, especially the combined endpoint of sudden death and potentially lethal arrhythmic events. Our results suggest that longer periods of exposure to MVO might lead to unfavorable consequences. They also support the principle that the presence of MVO in patients with HCM has important pathophysiological implications.

Myocardial fat at cardiac imaging: how can we differentiate pathologic from physiologic fatty infiltration?

Myocardial fat is often seen at cardiac computed tomography (CT) and magnetic resonance (MR) imaging of healthy adults and patients with myocardial diseases. Physiologic myocardial fat develops with aging and is commonly seen at CT in the anterolateral right ventricular (RV) free wall and RV outflow tract with normal or thickened RV myocardium and a normal-sized RV in elderly patients. Pathologic conditions with myocardial fat include healed myocardial infarction (MI); arrhythmogenic RV cardiomyopathy or dysplasia (ARVC); and others, such as cardiac lipoma, lipomatous hypertrophy of the interatrial septum, tuberous sclerosis complex, dilated cardiomyopathy, and cardiomyopathy with muscular dystrophy. In patients with healed MI, CT and MR imaging show fat in left ventricular myocardium that is of normal thickness or thin and follows the distribution of the coronary artery; CT often depicts fat in mostly subendocardial regions. In patients with ARVC, characteristic CT and MR imaging findings include a thin RV outflow tract and free wall caused by subepicardial fatty infiltration; fat in the RV moderator band, trabeculae, and ventricular septum; and RV enlargement and wall motion abnormality. Recognition of patient age, characteristic locations of myocardial fat, myocardial thickness, and ventricular size helps in differentiating physiologic and pathologic myocardial fat at cardiac imaging; findings of wall motion abnormality and late gadolinium enhancement at MR imaging help narrow the diagnosis.

Image integration of three-dimensional cone-beam computed tomography angiogram into electroanatomical mapping system to guide catheter ablation of atrial fibrillation.

AIMS: To evaluate the feasibility of integrating three-dimensional images created by intra-procedural cone-beam computed tomography (CBCT) into three-dimensional electroanatomical maps (EAM) and compare its accuracy with that of pre-procedural multi-slice CT (MSCT). METHODS AND RESULTS: In 24 patients with drug-refractory atrial fibrillation (AF), atriography using CBCT with pulmonary arterial contrast injection was performed at the beginning of the AF ablation procedure. Intra-procedural CBCT images and pre-procedural MSCT images were individually imported into the EAM system and compared their integration accuracy (point-to-surface distance) of each image and EAM just before ablation. The CBCT images were assessed qualitatively and quantitatively in comparison with MSCT images. All CBCT images were graded as optimal or useful in delineating the left atrium-pulmonary vein anatomy and were successfully integrated with the EAM. Overall, integration accuracy was similar for CBCT and MSCT. However, in 11 patients, the MSCT was performed 5 or more days prior to EAM, resulting in significantly shorter surface-to-point distance in CBCT than that in MSCT (P = 0.047). Radiation exposure with CBCT was significantly reduced compared with MSCT (P < 0.001). CONCLUSION: It is feasible to integrate CBCT image into EAM, and the integration is relatively accurate. Intra-procedural atriography by CBCT may replace pre-procedural MSCT as the imaging source for image integration.

Ability of 201Tl and 123I-BMIPP mismatch to diagnose myocardial ischemia in patients with suspected coronary artery disease.

OBJECTIVE: A mismatch defect between (201)TL and (123)I-BMIPP dual isotope SPECT (d-SPECT) is useful to detect myocardial ischemia in patients with acute coronary syndrome. However, whether mismatched d-SPECT findings reflect actual myocardial ischemia in stable patients with suspected, but unknown ischemic heart disease is unclear. The present study assesses the significance of a d-SPECT mismatch among such patients. METHODS: Forty-nine patients with suspected stable coronary heart disease who had been referred for chest pain, ECG abnormalities or multiple risk factors (66 +/- 11 years old, 34 males) with a d-SPECT mismatch participated in this study. All of them underwent coronary angiography (CAG) to assess coronary artery disease. The entire myocardial area on d-SPECT images was divided into 17 segments, each of which was scored from 0 (normal) to 4 (defect). The d-SPECT mismatch score (MS) was defined as the summed BMIPP defect score (BM-TDS) minus the summed defect score (TL-TDS). The inclusion criterion was MS >or= 1, and the mismatch was defined as true positive if the mismatched area was concordant with the territories supplied by significant coronary stenotic arteries by CAG. RESULTS: Ischemic heart disease was judged by coronary angiography in 31 (63%) patients (IHD group), of which 24 (49.0%) were true positives. Of the remaining 18 (37%) patients without no significant coronary stenosis (non-IHD group), 12 (24%) had some types of organic heart disease. If MS >or= 4 was defined as the threshold for an ischemic positive mismatch, then the sensitivity and specificity were 80% and 63%, respectively. However, mismatch scores did not significantly differ between the groups with true positive-IHD and organic heart disease in non-IHD group (6.6 +/- 4.4 vs. 6.4 +/- 3.7). CONCLUSION: A d-SPECT mismatch score of >or=4 was an appropriate cutoff at which diagnosis of myocardial ischemia in patients who were screened for ischemic heart disease. However, since patients with non-ischemic but organic heart disease can also present with abnormal mismatch findings, coronary angiography or CT might be warranted to differentiate IHD from non-IHD.