Inter-observer agreement and diagnostic accuracy of myocardial perfusion reserve quantification by cardiovascular magnetic resonance at 3 Tesla in comparison to quantitative coronary angiography

Background

Quantification of cardiovascular magnetic resonance (CMR) myocardial perfusion reserve (MPR) at 1.5 Tesla has been shown to correlate to invasive evaluation of coronary artery disease (CAD) and to yield good inter-observer agreement. However, little is known about quantitative adenosine-perfusion CMR at 3 Tesla and no data about inter-observer agreement is available. Aim of our study was to evaluate inter-observer agreement and to assess the diagnostic accuracy in comparison to quantitative coronary angiography (QCA).

Methods

Fifty-three patients referred for coronary x-ray angiography were previously examined in a 3 Tesla whole-body scanner. Adenosine and rest perfusion CMR were acquired for the quantification of MPR in all segments. Two blinded and independent readers analyzed all images. QCA was performed in case of coronary stenosis. QCA data was used to assess diagnostic accuracy of the MPR measurements.

Results

Inter-observer agreement was high for all myocardial perfusion territories (ρ = 0.92 for LAD, ρ = 0.93 for CX and RCA perfused segments). Compared to QCA receiver-operating characteristics yielded an area under the curve of 0.78 and 0.73 for RCA, 0.66 and 0.69 for LAD, and 0.52 and 0.53 for LCX perfused territories.

Conclusions

Inter-observer agreement of MPR quantification at 3 Tesla CMR is very high for all myocardial segments. Diagnostic accuracy in comparison to QCA yields good values for the RCA and LAD perfused territories, but moderate values for the posterior LCX perfused myocardial segments.     

Incremental value of dual-energy CT to coronary CT angiography for the detection of significant coronary stenosis: comparison with quantitative coronary angiography and single photon emission computed tomography

To determine the value of dual-energy CT (DECT) and combined information of perfusion and angiography in diagnosing coronary artery disease (CAD), with single photon emission computed tomography (SPECT) and quantitative coronary angiography (QCA) as a reference standard. Thirty-four patients were enrolled in this study. DECT was used as a contrast-enhanced retrospectively ECG-gated scan protocol during the rest state and tubes were set at 140/100 kV. DECT angiography (DE-CTA) and DECT perfusion (DE-CTP) were calculated from two kV images. DE-CTP results were compared with SPECT and DE-CTA with QCA, respectively. The combined DE-CTP with DE-CTA data were compared to QCA in diagnosis of obstructive CAD (stenosis ≥ 50%). DECT showed diagnostic image quality in 31 patients. Using SPECT as a reference, DE-CTP had sensitivity of 68%, specificity of 93%, and sensitivity of 81%, and specificity of 92% for identifying any type of perfusion deficits on the segment- and territory-based analysis, respectively. Using QCA as a reference standard, DE-CTA showed sensitivity of 82%, specificity of 91% and accuracy of 86% for detecting ≥50% coronary stenosis on the vessel-based analysis, whereas the combination of DE-CTA and DE-CTP gave sensitivity of 90%, specificity of 86% and accuracy of 88% for detecting ≥50% coronary stenosis, respectively. Combination of DE-CTP and DE-CTA may improve diagnostic performance compared to CTA alone for the diagnosis of significant coronary stenosis.     

Color-Encoded Semiautomatic Analysis of Multi-Slice First-Pass Magnetic Resonance Perfusion: Comparison to Tetrofosmin Single Photon Emission Computed Tomography Perfusion and X-Ray Angiography

BACKGROUND AND PURPOSE: Cardiovascular magnetic resonance (CMR) perfusion can accurately detect coronary artery disease (CAD). However, the absence of efficient, easy-to-use and reliable image analysis software is an obstacle to its introduction into clinical practice. The aim of this study was to evaluate new color-encoded semiautomatic software for analysis of first-pass CMR perfusion in comparison to tetrofosmin myocardial single photon emission computed tomography (SPECT), using X-ray angiography as the standard of truth for the detection of CAD. METHODS: Thirty-two patients underwent both SPECT and CMR perfusion at rest and adenosine stress. Twenty of these patients also underwent X-ray angiography. Off-line CMR image analysis consisted of six steps to generate a color display of the myocardial perfusion reserve index (MPRI). The MPRI color-maps were analyzed visually and compared to SPECT. RESULTS: In comparison to X-ray angiography overall accuracy was 87% for CMR and 77% for SPECT perfusion to detect significant CAD (stenosis > or =70%). In comparison with SPECT sensitivity was 80%, specificity 91%, and the overall agreement 89% for CMR. CONCLUSIONS: Post-processing of CMR perfusion data using new semiautomatic software to generate and display the MPRI visually as color-encoded images is feasible and fast. In this study it yielded higher accuracy than SPECT to detect significant CAD on X-ray angiography. Correlation between SPECT and CMR accuracy for detection of perfusion defects was high. This method may accelerate the time-consuming analysis of CMR perfusion data, thus enabling a more widespread clinical utility.     

Comparison of thallium-201 exercise SPECT and dobutamine stress echocardiography for diagnosis of coronary artery disease in patients with left bundle branch block

The present study assessed and compared the diagnostic accuracy of thallium-201 (Tl-201) exercise myocardial single photon emission computerised tomography (SPECT) and dobutamine stress echocardiography (DSE) for detection of coronary artery disease (CAD) in patients with left bundle branch block (LBBB). Study population consisted of 26 consecutive patients with permanent LBBB who were suffering from chest pain. Patients (8 women, 18 men mean age = 57 ± 8 years) were studied with DSE, Tl-201 SPECT and coronary angiography (CAG). Three different approaches for diagnosis of CAD were used to identify CAD in left arterial descending (LAD) coronary artery territories in scintigraphic studies: (1) Approach A (conventional approach): involvement of septal, and/or anterior, and/or apical wall. (2) Approach B: involvement of anterior and septal wall irrespective of apical wall. (3) Approach C: involvement of septum, anterior and apical wall. DSE gave a sensitivity of 91%, specificity of 92% and accuracy of 92% for diagnosis of CAD in the LAD coronary artery territory. Tl-201 SPECT (conventional approach) gave a sensitivity of 100%, specificity of 42% and diagnostic accuracy of 69% for diagnosis of CAD in the LAD coronary artery territory. Sensitivity, specificity and diagnostic accuracy of approach C were 33, 85 and 57% respectively. The specificity of Tl-201 SPECT significantly increased in approach C when compared with approach A and B (p < 0.02). However sensitivity of the Tl-201 SPECT with approach C showed significant decrease when compared with DSE and approach A and B (p < 0.005). Specificity of DSE for diagnosis of CAD in LAD were significantly higher than those of Tl-201 SPECT regarding the approach A and B (p < 0.01). In conclusion the use of DSE for diagnosis of CAD in patients with LBBB seems to be more suitable than Tl-201 SPECT.     

Adenosine stress cardiac magnetic resonance imaging for the assessment of ischemic heart disease

Aims  This prospective study was designed to determine the diagnostic value of adenosine stress cardiac magnetic resonance imaging (CMRI) in patients referred to elective coronary angiography. Methods and results  Myocardial perfusion measurements at rest and adenosine stress were performed in 141 patients (105 men, 36 women, mean age 63.4 years) at 1.5 T with a Turbo Flash sequence. Stress-induced perfusion deficits were correlated to angiographic stenoses ≥75%. The overall sensitivity for CMRI depicting coronary artery disease (CAD) with relevant stenoses was 90.4%, the specificity was 77.4%, the positive predictive value was 85.9%, the negative predictive value was 84.2% and the accuracy 85.2%. Subgroup analysis was performed for 3-vessel disease (n = 44, sensitivity 92.3%, specificity 75.0%), 2-vessel disease (n = 43, sensitivity 92.6%, specificity 92.9%), 1-vessel disease (n = 27, sensitivity 93.1%, specificity 71.4%) and patients without CAD (n = 27, specificity 70.4%) as well as for patients with prior myocardial infarction (n = 44, sensitivity 92.9%, specificity 86.7%), prior coronary artery bypass surgery (n = 21, sensitivity 88.2%, specificity 66.7%), prior coronary interventions (n = 88, sensitivity 91.9%, specificity 75.0%), or diabetics (n = 27, sensitivity 90.5%, specificity 83.3%). Conclusion  Our study shows that stress perfusion CMRI can accurately predict relevant CAD and contributes to the identification of hemodynamic relevant stenoses in patients scheduled for coronary angiography. C. Doesch and A. Seeger have equally contributed to this publication.     

ASCI 2010 contrast media guideline for cardiac imaging: a report of the Asian Society of Cardiovascular Imaging cardiac computed tomography and cardiac magnetic resonance imaging guideline working group

To evaluate the accuracy of myocardial perfusion SPECT (MPI) in the detection and allocation of vessel specific perfusion defects (PD) using standard distribution territories in a routine clinical procedure of patients with multivessel disease (MVD). Combined quantitative coronary angiography and fractional flow reserve (QCA/FFR) measurements were used as invasive reference standard. 216 vessels in 72 MVD patients (67 ± 10 years, 28 female) were investigated using MPI and QCA. FFR of 93 vessels with intermediate stenoses was determined. MPI detected significant stenoses according to QCA/FFR findings with a sensitivity of 85%. However, vessel-based evaluation using standard myocardial distribution territories delivered a sensitivity of only 62% (28 MPI+ out of 45 (QCA/FFR)+ findings), with specificity, PPV and NPV of 90, 62 and 90%. 7/17 false positive and 7/17 false negative findings (41%) could be attributed to incorrect allocation of reversible PD to their respective coronary arteries. 6/17 (35%) perfusion territories were classified as false negative when additional fixed PD were present. MPI had reasonable sensitivity for the detection of significant coronary artery disease in patients with multivessel disease. However, sensitivity decreased markedly, when the significance of each individual stenosis was evaluated using standard myocardial supplying territories. In this setting, 41% of false negative and false positive MPI findings resulted from incorrect allocation of reversible perfusion defects to their determining supplying vessel.     

SPECT门控心肌灌注显像定量分析的诊断价值

目的:探讨SPECT门控心肌灌注显像定量分析在提高诊断准确性方面的应用价值。方法:回顾分析112例具有完整的~(99m)Tc-MIBI门控静息/负荷心肌灌注显像资料和冠状动脉造影结果的患者资料。由3名有经验的核医学医师首先对SPECT心肌灌注显像的断层图像进行了分析并做出诊断,然后应用定量分析软件对门控图像进行定量分析获得左心室射血分数(LVEF)等功能指标并动态显示室壁运动情况,结合断层图像再次进行图像分析。以冠状动脉动脉造影的结果为标准,对比分析是否应用定量分析软件时诊断的敏感性、特异性和准确性。分析除LVEF外的其他功能性指标对诊断是否具有帮助。结果:112例患者冠状造影结果显示共计有147支冠状动脉管腔狭窄>50%。单纯SPECT心肌灌注显像断层图像目测分析诊断的敏感性、特异性和准确性分别为91.8%、86.8%和90.0%。综合分析断层图像与定量分析指标,诊断的敏感性、特异性和准确性分别为95. 9%、94.2%和94.9%。除LVEF外,其他定量分析指标被认为对诊断具有帮助的占59.8%(67/112),认为不确定者23.2%(26/ 112),认为没有价值者占17.0%(19/112)。结论:借助于定量分析软件可以明显的提高SPECT心肌灌注显像诊断的准确性。     

新型心肌灌注显像剂^99mTc—tetrofosmin诊断冠心病的价值

目的：探讨新型心肌灌注显像剂^99mTc-tetrofosmin诊断冠心病的临床价值。材料与方法：对59例确诊或疑诊并已行冠状动脉造影的患者进行运动。静息心肌灌注断层显像,分别在运动高峰及静息状态静脉注射^99mTc-tetrofosmin740MBq后30－60min按常规方法做SPECT断层采集。结果：在注射^99mTc-tetrofosmin的后无任何不适反应,并获得良好心肌断层图像,以冠状动脉造影结果为金标准,^99mTc-tetrofosmin诊断冠心病的灵敏度、特异性及准确度分别为89．1％,84．6％及88．1％。结论：^99mTc-tetrofosmin具有标记简便,给药后无需脂餐促排、显像时间短、图像质量清晰及诊断准确度较高等特点,有着良好的临床应用前景。     

腺苷超声与核素心肌显像推测心绞痛相关狭窄血管的比较

目的 比较腺苷超声心动图与腺苷核素心肌灌注显像诊断冠心病及推测稳定型心绞痛患者相关狭窄血管的价值。方法 51例临床诊断为稳定型心绞痛的住院患者同期进行腺苷超声心动图与腺苷核素心肌灌注显像检查,超声心动图示室壁运动障碍,心肌显像检测核素分布稀疏或缺损,并在2周内行冠状动脉造影对照。结果 51例患者接受冠状动脉造影,诊断冠心病42例,9例排除冠心病,诊断狭窄血管74支。超声心动图阳性者33例,心肌显像阳性者39例。超声心动图诊断狭窄血管敏感性62%,特异性86%,准确性75%。核素心肌显像诊断狭窄血管敏感性80%,特异性89%,准确性84%。二者诊断符合率84%。结论 研究结果显示,与腺苷超声心动图诊断稳定型心绞痛患者狭窄血管相比较,腺苷心肌灌注显像具有更高的敏感性,尤其识别多支病变及中重度狭窄血管更敏感。     

CT angiography for evaluation of coronary artery disease in inner-city outpatients: an initial prospective comparison with stress myocardial perfusion imaging

To evaluate the utility of CT coronary angiography (CTA) for demonstrating coronary artery disease in inner-city outpatients, we prospectively compared CTA with stress SPECT myocardial perfusion imaging in an ethnically diverse, gender balanced population. All patients gave written informed consent for this IRB approved, HIPAA compliant study. Sixty-one patients completed both CTA and SPECT. About 67% were ethnic minorities, 51% were women. A stenosis of ≥70% on CTA was considered positive. Results were compared with perfusion defects on SPECT and correlated with clinical endpoints (hospital admissions, cardiovascular events, coronary interventions and deaths). CTA and SPECT data were compared with results of coronary angiography, when performed. There was moderate global agreement of 79% (48/61) between CTA and SPECT, κ = 0.483 (SE ± 0.13, P = 0.0001). With SPECT as the reference standard, CTA had sensitivity of 73% (11/15), specificity of 80% (37/46), negative predictive value of 90% (37/41) and positive predictive value of 55% (11/20). Positive SPECT was associated with positive CTA, (P < 0.0001, OR = 22). Eleven (18%) underwent subsequent cardiac catheterization, which was positive in 91% (10/11). CTA and SPECT had positive predictive values of 90 and 83% compared with catheterization. This study lends preliminary evidence to support to the utility of CTA as an alternative modality for the evaluation of CAD in an ethnically diverse, gender balanced inner-city outpatient population. Similar to more homogenous groups, CTA had a high negative predictive value and demonstrated disease occult to SPECT. Further study is necessary to evaluate the impact of CTA on patient outcomes.     

Diagnostic accuracy of myocardial perfusion imaging with single photon emission computed tomography and positron emission tomography: a comparison with coronary angiography

Objective The aim of this study was to compare the diagnostic accuracy of myocardial perfusion imaging (MPI) by positron emission tomography (PET) with the diagnostic accuracy of MPI by single photon emission computed tomography (SPECT) in two comparable patient cohorts, using coronary angiography (CA) as the standard of reference. Methods A “SPECT-group” of 80 patients (15 female, 65 male; mean age 60 ± 9 years) and a “PET-group” of 70 patients (14 female, 56 male; mean age 57 ± 10 years) underwent a one day stress/rest examination either with attenuation-corrected ¹³N-ammonia PET or attenuation-corrected ²⁰¹TlCl SPECT or ^99mTc-hexakis-methoxy-isobutyl-isonitril (MIBI) SPECT. PET and SPECT results were semiquantitatively graded using a 6-segment heart model. All patients underwent CA, and stenoses were graded as a diameter reduction ≥50%. Results Coronary findings between both groups did not significantly differ at CA. For the SPECT-group overall sensitivity and specificity for localisation of stenoses was 77% and 84%. Respective values for the PET-group were 97% and 84%. The specificity of MPI by SPECT in the detection of ischemia was 74% and 91% for MPI by PET. The diagnostic accuracy of MPI improves when the individual coronary dominance and previous coronary revascularisations are taken into account. Conclusion MPI by ¹³N-ammonia PET is more sensitive in the detection and localisation of coronary stenoses, and more specific in the detection of ischemia than MPI by ²⁰¹TlCl/^99mMIBI SPECT.     

Quantification of left ventricular volumes and ejection fraction from gated 99mTc‐MIBI SPECT: MRI validation of the exini heart software package

The aim of the study was to validate the accuracy of the exini heart software (exini ) package in assessing left ventricular end‐diastolic/systolic volumes (EDV, ESV) and ejection fraction (LVEF) from gated ^99mTc‐MIBI single‐photon emission tomography (SPECT). Cardiac magnetic resonance imaging (cMRI) was used as reference. Furthermore, effects of perfusion defects and image quality in SPECT on correlation between gated SPECT and magnetic resonance imaging were investigated. Methods: Seventy patients were examined using gated SPECT (rest study, eight gates per cardiac cycle). EDV, ESV and LVEF were calculated from gated SPECT using exini . Directly before or after SPECT, cMRI (20 gates cardiac per cycle) was performed. EDV, ESV and LVEF were calculated using Simpson’s rule. Perfusion defects were quantified using the summed‐rest‐score (SRS). Total number of myocardial counts were used to rate image quality. Results: Correlation between results of gated SPECT and cMRI was high for EDV (R = 0·89) and ESV (R = 0·94) and good for LVEF (R = 0·78). ESV (exini 54 ± 31 ml versus cMRI 57 ± 34 ml) and LVEF (exini 62·9 ± 11·7% versus cMRI 60·6 ± 13·9%) did not differ significantly whereas exini overestimated EDV significantly compared with cMRI (exini 144 ± 41 ml versus cMRI 137 ± 36 ml; P<0·005). No correlation was found between absolute differences of the results given by gated SPECT and cMRI and SRS or total myocardial counts (R < 0·18). Conclusion: End‐diastolic volume, ESV and LVEF calculated from gated SPECT using exini agree with cMRI over a wide range of values. Correlation between both the methods was good for EDV and ESV, and acceptable for LVEF. No relevant influence of image quality or SRS on the accuracy of exini results was found.     

Value of additional myocardial perfusion imaging during dobutamine stress magnetic resonance for the assessment of intermediate coronary artery disease

This study was performed to assess the role of additional myocardial perfusion imaging during high dose dobutamine/atropine stress magnetic resonance (DSMR-wall motion) for the evaluation of patients with intermediate (50?C70%) coronary artery stenosis. Routine DSMR-wall motion was combined with perfusion imaging (DSMR-perfusion) in 174 consecutive patients with chest pain syndromes who were scheduled for a clinically indicated coronary angiography. When defining CAD as the presence of a????50% stenosis, the addition of perfusion imaging improved sensitivity (90 vs. 79%, P?<?0.001) with a non-significant reduction in specificity (85 vs. 90%, P?=?0.13) and an improvement in overall diagnostic accuracy (88 vs. 84%, P?=?0.008). Adding perfusion imaging improved sensitivity in patients with intermediate stenosis (87 vs. 72%, P?=?0.03), but not in patients with severe (??70%) stenosis (93 vs. 84%, P?=?0.06). In patients with severe stenosis specificity of DSMR-perfusion versus DSMR-wall motion decreased (61 vs 70%, P?=?0.001) resulting in a lower overall accuracy (71 vs 74%, P?=?0.03). Using a cutoff of ??50% for the definition of CAD, sensitivity of DSMR-perfusion compared to DSMR-wall motion was significantly higher in patients with single vessel (88 vs. 77%, P?=?0.03) and multi vessel disease (93 vs. 79%, P?=?0.03), whereas no significant differences were found using a cutoff of ??70% stenosis for the definition of CAD. The addition of perfusion imaging during DSMR-wall motion improved the sensitivity in patients with intermediate coronary artery stenosis. Overall diagnostic accuracy increased only when defining CAD as ??50% stenosis. In patients with ??70% stenosis DSMR-wall motion alone had higher accuracy due to more false-positive cases with DSMR-perfusion.     

The accuracy of 1-day dual-isotope myocardial SPECT in a population with high prevalence of coronary artery disease

Background: In order to evaluate the diagnostic efficacy of the 1-day separate acquisition dual-isotope single-photon emission computed tomography (SPECT) protocol, using ²⁰¹Tl for the rest and ^99mTc-tetrofosmin for the stress images, a consecutive series of patients with suspected or known coronary artery disease (CAD) was studied that also underwent coronary angiography. Methods: The results of myocardial SPECT, using a semi-quantitative visual analysis, were acquired in 123 patients and compared with the results of coronary angiography. Sensitivity and specificity were calculated, using thresholds of 50 and 70% stenosis. As an alternative for specificity, the normalcy rate was determined in a separate group of 87 patients with a <5% pre-test likelihood of CAD. Results: The prevalence of CAD using 50 and 70% stenosis was 88 and 78%, respectively. The sensitivity for detection of patients with 50 and 70% stenosis was 94 and 97%, respectively while specificity was 62 and 59%, respectively. The high rate of false positive perfusion defects resulting in a low specificity could be explained by specific clinical issues. However, the routine assessment with additional clinical and electrocardiographic data resulted in a correct interpretation of most of the false positive perfusion defects. The positive predictive value was 92 and 85% and the negative predictive value 46 and 77%, using thresholds of 50 and 70% stenosis, respectively. The normalcy rate was 91%. Conclusion: The one-day separate acquisition rest ²⁰¹Tl/stress ^99mTc-tetrofosmin SPECT protocol is an efficient procedure for myocardial perfusion scintigraphy with high sensitivity for detection of CAD. Specific clinical issues caused a low value for specificity. Therefore, clinical information and knowledge of the electrocardiogram is essential for a correct interpretation of SPECT images.     

心肌灌注显像在女性冠心病诊断中价值

目的评价心肌灌注显像对女性冠心病患者的诊断价值。方法 344例有胸痛、胸闷症状女性患者,行静息+药物负荷心肌灌注显像检测,并与冠状动脉造影结果进行对比分析。结果冠状动脉狭窄178例患者中心肌灌注显示异常者130例;冠状动脉造影无异常或不规则166例中心肌灌注显像异常50例,无异常116例;以冠状动脉造影结果为标准,心肌灌注显像对女性冠心病诊断的敏感度、特异度、阳性预测值、阴性预测值分别为73.0%,69.9%,72.2%,70.7%。结论心肌灌注显像对女性冠心病患者的诊断及是否进一步行冠状动脉造影的筛选有一定价值。     

Accuracy of quantitative coronary angiography with computed tomography and its dependency on plaque composition

Objective: To determine the impact of plaque composition on accuracy of quantitative 64-slice computed tomography coronary angiography (CTCA). Methods: The institutional review board approved this study; written informed consent was obtained from all patients. One hundred consecutive patients (42 women, mean age 64.6 ± 9.4 years, age range 39–87 years) underwent CTCA and invasive quantitative coronary angiography (QCA) to determine (a) the diagnostic accuracy of CTCA for the detection of significant stenosis (diameter reduction of ≥50%), and (b) the accuracy of stenosis grading. In CTCA stenosis severity was graded in 10% steps and evaluated separately for calcified and non-calcified coronary lesions using Pearson-linear-regression analysis, Bland/Altman-analysis (BA), and Mann-Whitney-U-test. Results: In 60/100 patients 139 significant coronary artery stenoses were identified with QCA. On a per-segment analysis, sensitivity of CTCA was 75.5%, and specificity was 96.6% (positive predictive value: 72.9%, negative predictive value: 97.0%). Quantification of stenosis grading correlated moderately between methods (r = 0.60; P < 0.001), with an overestimation by CTCA of 5.5% (BA limits-of-agreement −29 to 39%). BA limits-of-agreement were greater in calcified lesions (−29.2 to 45.6%; mean error 8.2%) than in non-calcified lesions (−25.9 to 30.2%; mean error 2.2%) and differed significantly (P < 0.05). Conclusions: Diagnostic accuracy of CTCA is high, however agreement for quantitative lesion severity assessment between CTCA and QCA is moderate for calcified but superior for non-calcified lesions.     

MRI检测活性心肌及其与冠状动脉造影、SPECT和PET对比研究

目的：分析MRI对冠心病患者心肌活性的诊断价值并与冠状动脉造影、SPECT和PET结果对比。方法：应用MRI对21例临床符合冠心病的患者进行检查，并将结果与冠状动脉造影、SPECT和PET检查结果对照。结果：MRI静息心肌灌注扫描检出的缺血节段比狭窄冠状动脉的供血节段少但无统计学差异（Z=-1.732，P=0．083）；比SPECT心肌灌注扫描检出的缺血节段多且有统计学差异（Z=-3．691，P=0．000）。SPECT心肌灌注扫描检出的缺血节段比狭窄冠状动脉的供血节段少且有统计学差异（Z=-3．029，P=0．002）。以正电子发射断层显像（PET）结果为标准，MR延迟扫描检测活性心肌的灵敏度为97．6％，特异度为98．4％，总符合率为98．2%，Kappa值为0．953。MR延迟扫描检出的活性心肌比PET检出的少但无统计学差异（Z=-0．209，P=0．835）。结论：MR心脏检查清晰显示心肌梗死的位置、程度和附壁血栓情况，并可对左室室壁运动进行直观显示。常规SPECT心肌灌注显像由于空间分辨率低明显低估心肌缺血范围。心肌PET显像空间分辨率低，无法显示心肌梗死的透壁程度，且不能直观显示室壁运动情况。     

Noninvasive diagnosis of coronary artery disease in patients with diabetes by dobutamine stress real-time myocardial contrast perfusion imaging

OBJECTIVE: The aim of this study was to assess the accuracy of real-time myocardial contrast perfusion imaging (MCPI) during dobutamine stress in the diagnosis and localization of coronary artery disease (CAD) in patients with diabetes. Myocardial contrast echocardiography is a new technique that allows evaluation of myocardial perfusion. Its utility in diabetic patients has not been defined. RESEARCH DESIGN AND METHODS: Dobutamine-atropine stress test was performed in conjunction with MCPI using Optison or Definity at rest and at peak stress in 128 patients with diabetes and suspected CAD who underwent coronary angiography within 1 month. CAD was defined as > or =50% stenosis in one or more coronary artery. MCPI was considered diagnostic of CAD in the presence of reversible perfusion abnormalities. The normalcy rate of MCPI was additionally determined in 18 asymptomatic nondiabetic patients with low probability. RESULTS: CAD was detected in 101 (79%) patients by angiography. Reversible perfusion abnormalities were detected in 90 patients with and 13 patients without CAD. The overall sensitivity of MCPI was 89% (95% CI 83-95), specificity 52% (33-71), and accuracy 81% (75-88). Reversible abnormalities were detected in two or more vascular distributions in 44 of 56 patients with multivessel CAD and in 8 of 63 patients without (sensitivity 68%, specificity 87%, positive predictive value 84%, and accuracy 79%). Regional sensitivity was 75% (65-85) for left anterior descending CAD, 71% (60-83) for left circumflex, and 67% (55-78) for right CAD. MCPI was normal in 16 of the 18 patients with low clinical probability of CAD (normalcy rate 89%). CONCLUSIONS: MCPI is a useful noninvasive technique for the diagnosis and localization of CAD in diabetic patients. The extent of perfusion abnormalities can identify patients with multivessel CAD with a moderate sensitivity and high specificity.     

Detection of single‐vessel coronary artery disease by dipyridamole stress echocardiography: no longer a problem?

We aimed to evaluate whether addition of myocardial contrast echocardiography (MCE) perfusion data improves the sensitivity of stress echocardiography for detection of single‐vessel coronary artery disease (svCAD) and to compare the diagnostic value of MCE and single‐photon emission computed tomography (SPECT) for detection of svCAD. Methods One hundred and three patients with suspected or known stable CAD underwent dipyridamole (0·84 mg kg^?1 intravenously over 4 min)‐atropine (up to 1 mg intravenously) stress echocardiography combined with MCE. Wall motion abnormalities (WMA) and perfusion defects were assessed visually. Presence of CAD was detected by coronary angiography. Results Single‐vessel coronary artery disease defined as ≥70% stenosis was detected in 30% of patients, whereas 26% of patients had svCAD defined as ≥50% stenosis. Presence of inducible WMA had 35% and 26% sensitivity for detection of svCAD defined as ≥70% and ≥50% stenosis, respectively. Concomitant evaluation of MCE increased the sensitivity to 74% (P = 0·005) and 56% (P = 0·053), respectively, using any inducible abnormality (WMA or perfusion defects) as a criterion. Presence of any (inducible or fixed) WMA had 77% and 59% sensitivity for detection of svCAD defined as ≥70% and ≥50% stenosis, respectively. In case of such criterion for stress test positivity, the improvement in sensitivity provided by addition of MCE (to 94% and 78%, respectively) did not reach statistical significance. Conclusions Addition of MCE perfusion analysis during stress echocardiographical examination based on evaluation of inducible abnormalities improves the test sensitivity for detection of svCAD. This benefit is less apparent when fixed WMA and perfusion defects are incorporated into the stress test positivity criterion.     

Myocardial perfusion cardiac magnetic resonance for the diagnosis of coronary artery disease: do we need rest images?

Adenosine stress cardiovascular magnetic resonance (CMR) has been reported to be useful for the diagnosis of coronary artery disease (CAD). Most studies use rest and stress perfusion images. The objectives of this study were to determine (Barkhausen et al. in J Magn Reson Imaging 19(6):750–757, 1) the accuracy of visual assessment and myocardial perfusion reserve index (MPRI) in the diagnosis of CAD and (Rieber et al. in Fur Heart J 27(12):1465–1471, 2) the accuracy of analysis based on rest–stress and stress images. We enrolled patients with suspected CAD and referred them for coronary angiography (CAG). All the patients underwent adenosine stress CMR before CAG. Rest and stress perfusion images were analyzed by calculation of MPRI and visual assessment separately. Visual assessment was performed separately by using rest and stress images and by using only stress images. CAG was considered the gold standard. Sensitivity, specificity, and accuracy of both methods were calculated and compared. A total of 66 patients (mean age, 61.3 ± 11.7 years) were studied. Thirty-eight patients (57.6%) were diagnosed with CAD. The sensitivity and specificity for the diagnosis of CAD (≥50% stenosis) were 89.5 and 78.6% for MPRI, 76.3 and 75% for stress–rest visual method, and 86.8 and 75% for stress visual method, respectively. CMR perfusion had a relatively lower accuracy in patients with left ventricular systolic dysfunction, high left ventricular mass, or presence of late gadolinium enhancement than in patients without those CMR findings. Visual assessment of stress image of CMR perfusion is accurate and comparable to MPRI for the detection of CAD.