静息^99mTc—MIBI心肌灌注显像估测心肌梗塞患者预后的价值

目的探讨99mTc-MIBI静息心肌灌注显像估测心肌梗塞患者预后的价值.材料与方法追踪了74例行99mTc-MIBI静息心肌灌注显像的心肌梗塞患者,随访时间4～36月,平均23月,未发生心脏事件者随访时间≥12月.心脏事件包括心源性死亡,非致死性心肌梗塞,心肌显像三月后的血运重建术(CABG或PTCA).结果74例心肌梗塞患者随访中发生心脏事件23例,总发生率为31.1%.多因素Cox回归分析表明,心肌显像心肌灌注缺损节段数与发生心脏事件有密切关系(P＜0.001).31例心肌灌注缺损节段数≥4的心肌梗塞患者心脏事件发生率为61.3%,明显高于43例心肌灌注缺损节段数≤3心肌梗塞患者的9.3%(x2=22.73 P＜0.001).单因素时序检验(Log-rank)显示,两者未发生心脏事件率差异有显著性(x2=14.64P＜0.001).结论99mTc-MIBI静息心肌灌注显像心肌灌注缺损节段数是预测心肌梗塞患者日后发生心脏事件的较好指标.     

~(99m)Tc-MIBI心肌灌注断层显像对老年冠心病心脏事件的预后评价

目的 :探讨99mTc MIBI -(甲氧基异晴 )心肌灌注断层显像 (下称心肌显像 )对老年冠心病 (CHD)心脏事件的预测价值。方法 :对 3 2 4例老年 (≥ 60岁 )CHD患者进行99mTc MIBI核素心肌显像及 2 4h动态心电图 (动态ECG)和ECG等检查 ,并进行 10年随访观察心肌显像正常与否与CHD心脏事件的相关性。结果 :心肌显像正常组(A组 )和异常组 (B组 )年心脏事件发生率分别为 0 47%及 1 81% ,两组比较差异有显著意义 (P <0 0 1)。B组发生心源性猝死 (SCD) 2 0起 (8 2 6% ) ,A组无一例发生。SCD在 48起心脏事件中 ,心肌显像异常者 93 75 % ,其相近时期的运动ECG及ECG阳性者分别为 47 91%及 2 2 91% ,提示心肌显像对心肌缺血的诊断及CHD事件的预后比ECG及动态ECG有更高的临床价值[1] 。结论 :99mTc MIBI心肌显像检查对老年CHD患者心脏事件有较高的预测价值 ,是老年CHD患者判断预后的重要指标     

冠状动脉造影与核素心肌断层显像的对比分析

1996年10月～1998年1月，对临床拟诊为冠心病的41例患者，进行冠状动脉造影（CAG）和核素心肌断层显像（SPECT）检查，结果报道如下。1资料与方法1．1一般资料：本组41例，男28例，女13例，年龄38～71岁，平均年龄60±7．2岁。其中典型心绞痛23例，心肌梗塞18例，均符合WHO冠心病诊断标准。1．2检查方法：核素心肌断层显像：（1）静态显像：病人在安静状态下静脉注射99mTc－MIBI20mCi，1小时后取心脏垂直长轴，水平长轴和心脏短轴3个断层显像；（2）运动显像：采用踏车分级（次极量级）运动试验，在达到运动高峰时，静脉注射””TC…     

^99mTc—MIBI心肌灌注显像定量分析评价体外反搏治疗的疗效

研究99mTc－seastmibi心肌显像在评价体外反搏治疗后疗效中价值。方法：本文对18例接受了体外反搏治疗的冠心病心肌缺血,在治疗前后进行了99mTc－MIBI心肌灌注显像,并对其结果作了定性与定量评价。结果：经一疗程的体外反搏治疗后,18例中有16例心肌缺血有不程程度的改善,其缺血面积由治疗前35．44％±15．83％缩小到27．63％±1277％（P＜0．005）,相对灌注指数由0．69±0．12增加到0．72±0．12（P＜0.05）,有效率为88．9％;2例患有严重冠脉病变的患者,治疗中病情恶化,缺血面积有扩大。结论：应用99mTc－MIBI心肌显像定量分板是评价体外反搏治疗效果、观察心肌血流改善程度准确、可靠的方法。     

^99mTc—MIBI心肌灌注断层显像对老年冠心病心脏事件的预后评价

目的：探讨^99mTc-MIBI-（甲氧基异晴）心肌灌注断层显像（下称心肌显像）对老年冠心病（CHD）心脏事件的预测价值。方法：对324例老年（≥60岁）CHD患者进行^99mTc-MIBI核素心肌显像及24h动态心电图（动态ECG）和ECG等检查,并进行10年随访观察心肌显像正常与否与CHD心脏事件的相关性。结果：心肌显像正常组心源性猝死（SCD）20起（8．26％）,A组无一例发生。SCD在48起心脏事件中,心肌显像异常93．75％,其相近时期的运动ECG及ECG阳性者分别为47．91％,提示心肌显像对心肌缺血的诊断及CHD事件的预后比ECG及动脉ECG有更高的临床价值^[1]。结论：^99mTc-MIBI心肌显像检查对老年CHD患者心脏事件有较高的预测价值,是老年CHD患者判断预后的重要指标。     

改良硝酸甘油法介入^99mTc—MIBI心肌显像检测存活心肌的观察

目的：研究49例心肌梗塞患者PTCA术前及术后2－3个月进行药物介入核素心肌显像,研究改良硝酸甘油法（简称改良硝甘法）介入^99mTc-甲氧基异丁基异腈心肌显像对存活心肌的检测。方法：分别对33例改良组及16例普通组的心肌梗塞患者进行了静息－改良硝甘法和静息－普通硝甘法介入心肌显像,并于术后2－3个月重复显像。结果：改良组静息显像异常节段97个,改良硝甘法介入后有62个节段再填充,再填充率63．9％;普通组静息显像异常节段51个,普通硝甘法介入后有24个节段再填充,再填充率47．1％;两组差异有显著意义（P＜0．01）。经皮血管再通术后复查静息心肌显像,与术前硝甘法显像比较,灌注改善的预测准确率为90．7％和70．6％。结论：改良硝甘法介入可明显提高对存活心肌检测的灵敏度和特异性,且副作用少。     

不稳定型心绞痛患者全球急性冠状动脉事件注册评分与心肌灌注显像危险分层的相关研究

目的：研究不稳定型心绞痛患者^99mTc-甲氧基异丁基异腈（MIBI）负荷／静息门控心肌灌注显像危险度分层与全球急性冠状动脉事件注册（GRACE）评分的相关性。方法：2006年6月--2007年11月确诊为不稳定型心绞痛的住院患者37例。首先依据GRACE评分方法进行评分；然后行^99mTc-MIBI运动或腺苷负荷门控心肌灌注显像和静息心肌灌注显像，依据负荷／静息门控心肌灌注显像所测定的可逆性心肌缺血计分值（SDS）和负荷后左室射血分数（LVEF）将患者分为低危组和中危组。分析^99mTc-MIBI负荷／静息门控心肌灌注显像危险分层与GRACE评分的相关性。结果：37例患者均顺利完成^99mTc-MIBI运动或腺苷负荷门控心肌灌注显像和静息心肌灌注显像。低危组和中危组之间的GRACE评分有显著差异（P〈0．01）。GRACE评分与负荷状态下心肌缺血计分值（SSS）呈正相关（r=0．561，P〈0．01），与SDS呈正相关（r=0．623，P〈0．01），与静息状态下心肌缺血计分值（SRS）无关（r=0．175，P〉0．05）。结论：GRACE评分对不稳定型心绞痛患者的核素心肌灌注显像危险度分层有一定的预测价值。     

^99mTc—MIBI显像在恶性肿瘤中的应用进展

99mTc－MIBI（99m锝-甲氧基异丁基异腈）作为一种心肌显像剂，广泛应用于心肌显像，诊断冠心病及各种心肌疾患。实践中人们发现心肌并不是它唯一的靶器官。1989年，Hassan等[1]首次报道99mTc－MIBI显像可诊断肺癌,其后，国内外的许多研究均证实了多种恶性肿瘤细胞可特异性摄取99mTc－MIBI，摄取量远高于正常细胞，并且排出又慢于正常细胞[2]。因此99mTc－MIBI目前又作为一种肿瘤阳性显像剂，在肺癌、乳腺癌、甲状腺癌等各种恶性肿瘤的诊断中普遍应用［3，4］。199mTc－MIBI恶性肿瘤显像的机制恶性肿瘤细胞摄取99mTc－MIBI的机…     

^99mTc—MIBI肺摄取定量判断冠心病心功能的临床价值

目的：探讨^99mTc－甲氧基异丁基异腈（MIBI）肺摄取定量判断冠心病心功能的临床价值。方法：对心绞痛组、心梗组和对照组病人作^99mTc-MIBI单光子断层摄影术时测量其前位投影图的动静态的肺心比值（LHR);用核素心室显像测定左室射血分数（LVEF）。结果：心绞痛组和对照组LHR运动较静息时低（P＜0．01）;静息时心绞痛组较对照组高（P＜0．05）;运动时两者无显著差异;静息时心梗组较对照组和心绞痛组高（P＜0．01）;心绞痛组运动和静息LHR均与LVEF呈显著负相关（均P＜0．01）。结论：冠心病患者运动和静息时LHR升降有诊断价值,HLR有助于预测左心室功能。     

运动心肌灌注显像对可疑或确诊冠心病患者预后的判断价值

目的探讨运动心肌灌注显像对可疑或确诊冠心病患者预后的判断价值。方法对116例可疑或确诊冠心病患者行运动试验和心肌灌注显像,并进行心脏事件随访。结果得到随访资料106例,平均随访(25±8)个月,共发生心脏事件11例,单因素分析显示,年龄、陈旧性心肌梗死史、运动高峰心率、从静息到运动高峰的心率变化、运动高峰收缩压、从静息到运动高峰的收缩压变化、异常心肌显像、心肌灌注缺损数目和缺血容积率(IVR)的大小是预测心脏事件发生的有价值的危险因素。多因素逐步Lo-gistic回归分析显示,IVR的大小是心脏事件发生的最有价值的预测因子,IVR≥25%时心脏事件发生的危险性明显升高(相对危险度5.9,P<0.005);尤其当心肌灌注显像正常时,IVR<25%发生心脏事件的危险性极低。结论运动心肌灌注显像可作为预测可疑或确诊冠心病患者发生心脏事件的无创性检查方法;根据心肌灌注显像时IVR的大小可有效区分高危和低危患者。     

High prevalence of (99m)tc-tetrofosmin reverse perfusion pattern in patients with myocardial infarction and angiographically smooth coronary arteries

Background: There are no published data in the literature on the scintigraphic perfusion pattern in patients with myocardial infarction (MI) and normal coronary arteries (NCA) Objectives: To evaluate myocardial perfusion imaging in a series of patients with MI and NCA. Methods: Twenty-seven patients who had developed a MI and had NCA were studied. As a control group we included 27 patients with a recent MI and coronary artery disease (CAD). All patients underwent stress/rest tetrofosmin myocardial perfusion SPECT within 6 months from MI. Results: In patients with NCA tetrofosmin stress images revealed 41 hypoperfused segments in 17 patients (63%). On rest images, 13 segments remained unchanged, 4 showed partial reperfusion, 10 normalized and 14 worsened. Additionally, there were 18 new hypoperfused segments in nine patients. Therefore, perfusion worsened at rest in 18 patients (67%) (32 segments). Overall, at rest there were 49 hypoperfused segments in 22 patients (81%). In patients with CAD, stress images revealed 71 hypoperfused segments. On rest images, 39 segments remained unchanged, 16 showed partial reperfusion and 12 normalized. Four segments worsened at rest and only four patients (15%) showed new perfusion defects at rest. Conclusions: Myocardial perfusion with tetrofosmin might appear considerably worse at rest than at stress in patients with MI and NCA. Specifically, a reverse perfusion pattern in the infarct area is a frequent finding and is likely to be due to residual tissue viability. We postulate that in these patients the hyperemic response to exercise may mask resting underperfusion areas.     

Left ventricular cavity-to-myocardium count ratio in exercise and resting technetium-99m-tetrofosmin SPECT: correlation with left ventricular function

The aim of this study was to assess the value of the cavity-to-myocardium count ratio (C/M ratio) calculated in exercise and resting technetium-99m (Tc-99m) tetrofosmin single photon emission computed tomography (SPECT) images to identify patients with depressed exercise and resting left ventricular ejection fraction (LVEF). We studied 60 patients with recent coronary artery diseases (CAD) undergoing first-pass ventriculography to calculate LVEF and myocardial perfusion SPECT imaging to calculate left ventricular C/M ratios. The group A of 30 CAD patients with higher LVEF (40%) had significant higher C/M ratios than the group B of 30 CAD patients with abnormal LVEF (<40%) during exercise and rest. However, C/M ratios between exercise and rest did not differ significantly in the both groups A and B. There is significant correlation between exercise/rest LVEF and exercise/rest C/M ratios. Tc-99m tetrofosmin C/M ratios calculated SPECT perfusion images are useful parameters in identifying patients with depressed LVEF in CAD patients.     

Myocardial perfusion in patients with typical chest pain and normal angiogram

BACKGROUND: Approximately 10-30% of patients with typical chest pain present normal epicardial coronaries. In a proportion of these patients, angina is attributed to microvascular dysfunction. Previous studies investigating whether angina is the result of abnormal resting or stress perfusion are controversial but limited by varying inclusion criteria. Therefore, we investigated whether microvascular dysfunction in these patients is associated with perfusion abnormalities at rest or at stress. PATIENTS AND METHODS: In 58 patients (39 female, 19 male, mean age 58+/-10 years) with angina and normal angiogram as well as 10 control patients with atypical chest pain and normal coronaries (six female, four male, mean age 53+/-11 years) myocardial blood flow (MBF) was measured at rest and under dipyridamole using 13N-ammonia PET. Resting MBF and coronary flow reserve (CFR) as the ratio of hyperaemic to resting MBF were corrected for rate-pressure-product (RPP): normalized resting MBF (MBFn)=MBFx10,000/RPP and CFRn=CFRxRPP/10,000. RESULTS: Sixteen/58 patients had a normal CFRn (=2.5; group I; CFRn: 3.1+/-0.88); the same as the controls (CFRn: 3.3+/-0.74). Forty-two/58 patients presented a reduced CFRn (group II; CFRn: 1.78+/-0.57). Group II had both a higher MBFn (group II: 1.30+/-0.33 vs. Group I: 1.03+/-0.26; P<0.05 and vs. controls: 1.07+/-0.19; P<0.01) and a lower hyperaemic MBF (group II: 2.25+/-0.76 mL g-1 min-1 vs. Group I: 3.07+/-0.78 mL g-1 min-1; P<0.001 and vs. controls: 3.41+/-0.94 mL g-1 min-1; P<0.0001). CONCLUSION: Impaired CFRn in patients with typical angina and normal angiogram is owing to both an increased resting and reduced hyperaemic MBF. Therefore, PET represents a prerequisite for further studies to optimize treatment in individuals with anginal pain and normal coronary angiogram.     

Value of myocardial contrast echocardiography for predicting left ventricular remodeling and segmental functional recovery after anterior wall acute myocardial infarction.

OBJECTIVE: We sought to study the value of microvascular perfusion assessed by myocardial contrast echocardiography in predicting left ventricular remodeling after anterior wall acute myocardial infarction. METHODS: In 31 patients myocardial contrast echocardiography was performed up to 48 hours after acute myocardial infarction with determination of end-diastolic and end-systolic volumes, wall-motion score index, and myocardial perfusion score index (MPSI) at rest and under dobutamine stress at 6 months. Patients were classified into remodeling group (RG) (n = 19) and non-RG (n = 12), and, according to number of segments without opacification, reflow (< or =2 segments, n = 15) and no-reflow (>2 segments, n = 16) groups. RESULTS: Wall-motion score index (1.84 +/- 0.22 vs 1.64 +/- 0.3; P =.049), MPSI (1.53 +/- 0.25 vs 1.26 +/- 0.17; P =.006), and number of segments without contrast (3.11 +/- 2.23 vs 1.08 +/- 1.38; P =.018) were higher in RG than in non-RG. End-diastolic and end-systolic volumes, and wall-motion score index, increased significantly in RG at 6 months and decreased in non-RG. MPSI increased in RG (1.53 +/- 0.25-1.66 +/- 0.21; P =.011) and was the only independent predictor of left ventricular remodeling (odds ratio = 1.8; 95% confidence interval = 1.15-2.82; P =.010). No-reflow group presented 27.8 +/- 19.9% of segments with resting functional recovery or contractile reserve, and reflow group presented 69.9 +/- 31.2% (P <.001). CONCLUSION: MPSI obtained 48 hours after acute myocardial infarction is an independent predictor of left ventricular remodeling. Patients with two or fewer segments without opacification revealed a better prognosis of resting ventricular function and contractile reserve.     

The Significance of Left Ventricular Cavity-to-Myocardial Count Ratio in Patient with Angina Pectoris

为探讨心绞痛患者左窒腔、心肌计数比值(C/M)作为心功能参数的临床价值,选择30例冠心病心绞痛患者及7例正常人进行~(99m)Tc-MIRI心肌灌注显像,图像重建后在短轴图像得C/M比值。37例受检者中有14例同时行平衡法核素心功能检查,获得左室射血分数(LVEF)、最大射血率(PER)、最大充盈率(PFR)等心功能参数,与C/M比值作相关分析,相关系数分别为0.91、0.54、0.75。结果表明,心绞痛患者C/M比值可反映其左室整体收缩功能,C/M比值可作为一个新的心功能指标,应用于临床。     

Global longitudinal strain measured by two-dimensional speckle tracking echocardiography is closely related to myocardial infarct size in chronic ischaemic heart disease

2D-STE (two-dimensional speckle tracking echocardiography) is a novel echocardiographic modality that enables angle-independent assessment of myocardial deformation indices. In the present study, we tested whether peak systolic epsilon(parallel) (longitudinal strain) values measured by 2D-STE could identify areas of MI (myocardial infarction) as determined by CE MRI (contrast-enhanced magnetic resonance imaging). Conventional echocardiographic apical long-axis recordings were performed in 38 patients, 9 months after a first MI. Peak systolic epsilon(parallel) measured by 2D-STE in 16 left ventricle segments was compared with segmental infarct mass and transmurality assessed by CE MRI. Segmental values were averaged to global and territorial values for assessment of global function and myocardial function in the coronary distribution areas. CE MRI identified transmural infarction in 27 patients, and a mean infarct size of 36+/-25 g. Peak systolic epsilon( parallel) correlated with the infarct mass at the global level (r=0.84, P<0.001). A strain value of -15% identified infarction with 83% sensitivity and 93% specificity at the global level and 76% and 95% at the territorial level, and a strain value of -13% identified transmural infarction with 80% sensitivity and 83% specificity at the segmental level. Global infarct mass correlates with the wall motion score index (r=0.70, P<0.001), and left ventricular ejection fraction measured by MRI or echocardiography (r=-0.71 and -0.58, both P<0.001). In chronic infarction, peak systolic epsilon(parallel) measured by 2D-STE correlates with the infarct mass assessed by CE MRI at a global level, and separates infarcted from non-infarcted tissue. Global strain is an excellent predictor of myocardial infarct size in chronic ischaemic heart disease.     

Myocardial perfusion and wall motion in infarction border zone: assessment by myocardial contrast echocardiography.

Several mechanisms have been proposed to explain the decreased wall motion (WM) at the borders of myocardial infarction (MI). We used myocardial contrast echocardiography (MCE) to investigate the relation of perfusion to WM in infarcted border zones (BZs) 6 weeks after MI in 5 sheep. After quantifying the extent of WM abnormality and the perfusion defect, normal (NL), infarcted, and BZs were defined. Peak intensity after contrast was measured in acoustic units (AU). Radiolabeled microspheres were injected to measure regional blood flow. The heart was stained with 2,3, 5-triphenyltetrazolium chloride (TTC). The perfusion defect on MCE was 33% +/- 7% of the total myocardial area and correlated well with TTC (r = 0.92, P <.03). The BZ was 8% +/- 5% of the total myocardial area. Peak intensity after contrast was decreased in MI compared with BZ and NL (MI: 2.5 +/- 1.9 AU, BZ: 8.0 +/- 3.8 AU, P <.005; NL: 10.2 +/- 6.9 AU, P <.02) and comparable in NL and BZ. The blood flow measured by microspheres was not different in NL and BZ but was decreased in MI (NL: 1.6 mL/g/min, BZ: 1.5 +/- 0.5 mL/g/min, MI: 0.7 +/- 0.5 mL/g/min; P <.0001). In this model of chronic ovine MI, the BZ was small and its perfusion was preserved. These findings support the hypothesis that tethering of normal myocardial segments explains the abnormal wall motion noted at the borders of MI.     

Stress radionuclide myocardial perfusion imaging detects more residual ischemia than stress echocardiography following acute myocardial infarction

OBJECTIVES: This investigation sought to compare the abilities of stress radionuclide myocardial perfusion imaging and stress echocardiography to detect residual ischemia in patients following acute myocardial infarction (MI). BACKGROUND: Stress radionuclide myocardial perfusion imaging and stress echocardiography are both commonly used to assess patients (patients.) in the immediate post MI period. However, the relative value of these techniques in identifying post MI ischemia remains unclear. METHODS: Eighteen patients. underwent both dipyridamole radionuclide perfusion imaging and dobutamine stress echocardiography on the same day or on consecutive days, 3-7 days following uncomplicated acute MI. Pts. who had an acute percutaneous intervention were excluded. Images were reviewed with clinical information available, but blinded to the opposing modality, for perfusion defects, wall motion abnormalities (WMA), and evidence of ischemia (reversible defect(s) on perfusion imaging, worsening WMA on stress echocardiography). Of the 18 patients, 11 subsequently underwent cardiac catheterization. RESULTS: Perfusion imaging identified defects in 16 (89%) patients, of whom 15 (83% of total) were found to be ischemic. Stress echocardiography identified a fixed wall motion abnormality in 17 (94%) and ischemia in 8 (44%, p < 0.05 compared with perfusion imaging ischemia). Among 11 patients who underwent catheterization, there was a trend towards perfusion imaging identifying more ischemia in the territory of an obstructed (> or = 70%) vessel--100% (11/11) vs. 64% (7/11) for stress echocardiography (p = 0.09). CONCLUSION: In the immediate post-infarction period, dipyridamole stress radionuclide myocardial perfusion imaging more often shows evidence of residual ischemia than dobutamine stress echocardiography.     

门控心肌灌注显像相位分析在2型糖尿病无症状性心肌缺血患者中的应用价值

目的探讨99mTc标记的甲氧基异丁基异腈(99mTc-MIBI)门控静息/运动负荷心肌灌注显像(MPI)相位分析在2型糖尿病无症状性心肌缺血(SMI)患者中的应用价值。方法将符合条件的53例行门控静息/运动负荷MPI扫描的2型糖尿病患者纳入研究,根据心肌灌注结果将其分为灌注正常组和灌注异常组。比较两组门控相关数据及BW、SD异常的发生率。结果灌注异常组左心室BW和SD均高于灌注正常组(P<0.01)。灌注正常组中左心室BW、SD异常的发生率均显著低于灌注异常组(P<0.01)。结论门控静息/运动负荷MPI通过一次检查既可得到患者的心肌血流灌注情况,同时也可以得到患者左室心肌运动同步性等室壁运动的相关数据,对2型糖尿病SMI患者具有重要价值。     

Prognostic value of dobutamine-atropine stress myocardial perfusion imaging in patients with diabetes

OBJECTIVE: Exercise tolerance in patients with diabetes is frequently impaired due to noncardiac disease such as claudication and polyneuropathy. This study assesses the prognostic value of dobutamine stress myocardial perfusion imaging in patients with diabetes. RESEARCH DESIGN AND METHODS: A total of 207 consecutive diabetic patients who were unable to undergo exercise stress testing underwent dobutamine-atropine stress myocardial perfusion imaging. Follow-up was successful in 206 of 207 (99.5%) patients. A total of 12 patients underwent early (<60 days) revascularization and were excluded from the analysis. End points during follow-up were hard cardiac events, defined as cardiac death and nonfatal myocardial infarction. RESULTS: Abnormal myocardial perfusion was detected in 125 (64%) patients. During 4.1 +/- 2.4 years of follow-up, 73 (38%) deaths occurred, 36 (49%) of which were due to cardiac causes. Nonfatal myocardial infarction occurred in 7 (4%) patients, and 45 (23%) patients underwent late coronary revascularization. Cardiac death occurred in 2 of 69 (3%) patients with normal myocardial perfusion and in 34 of 125 (27%) patients with perfusion abnormalities (P < 0.0001). A multivariable Cox proportional hazard model demonstrated that, in addition to clinical and stress test data, an abnormal scan had an incremental prognostic value for prediction of cardiac death (hazard ratio 7.2, 95% CI 1.7-30). The summed stress score was an important predictor of cardiac death; the hazard ratio was 1.2 (95% CI 1.07-1.34) per one-unit increment. CONCLUSIONS: Dobutamine-atropine stress myocardial perfusion imaging provides additional prognostic information incremental to clinical data in patients with diabetes who are unable to undergo exercise stress testing.