The role of first-pass radionuclide angiography in the era of gated SPECT myocardial perfusion imaging

Summary  All is not bleak as to the future of RNA, but to do it right, we need to approach it based on evidence gleaned from well-conducted clinical studies. Only then will we determine the added value of exercise EF over MPI in patient management.     

门控心肌灌注SPECT在冠心病方面的应用进展

门控心肌灌注SPECT能同时获得心肌血流灌注情况和左心室功能参数,是目前核素心脏检查中常用的方法。此法可重复性强,在临床应用广泛,为冠心病患者的诊断、危险度分层、心肌活力评价、治疗、预后及疗效的评价提供了可靠的依据。     

门控断层显像在心肌灌注断层显像中的应用

使用门控心肌断层显像不但减低了心脏搏动产生的图像边缘模糊,提高了对心肌缺血诊断的灵敏度和特异性,而且通过傅立叶变换和图像边缘识别技术等图像处理技术,可以在一次采集的信息基础上同时获得心脏的心肌血流灌注、心肌活力、室壁运动、射血功能和收缩协调性等参数,提高了核素心脏检查的价值,为临床准确判断患者的心脏状况,选择治疗方案,预后及疗效评价提供了更可靠的数据。本文就其近年来的临床应用进行综述。     

Procedure guidelines for radionuclide myocardial perfusion imaging

Radionuclide myocardial perfusion imaging (MPI) is an established and non-invasive imaging technique with diagnostic and prognostic efficacy in the investigation of coronary artery disease. It is the only widely available test for assessing myocardial perfusion directly but there are variations in the way it is performed in different centres. Harmonization of practice, at least at a national level, is therefore essential, and clinical governance now makes it mandatory for practice to be based upon evidence whenever possible [ 1]. This is best achieved by expert analysis of the evidence and to this end the British Nuclear Cardiology Society (BNCS) in association with the British Cardiac Society (BCS) and the British Nuclear Medicine Society (BNMS) have developed procedure guidelines for tomographic myocardial perfusion imaging. A systematic literature search was performed and every effort was made to conform with the AGREE recommendations [ 2]. All recommendations are therefore based on either evidence from clinical studies, previous published guidelines or expert consensus of the writing and advisory groups. The guidelines cover the clinical indications of MPI, the methods used for stress testing, the radiopharmaceuticals and the injected activities and also issues related to acquisition, processing and interpretation of images. They do not cover the benefits or drawbacks of the technique in specific circumstances; neither do they address its cost effectiveness in clinical diagnosis and management nor its potential impact on clinical outcomes. The guidelines aim to assist medical practitioners and other health care professionals in recommending, performing, interpreting and reporting single photon emission computed tomography (SPECT) of myocardial perfusion.     

用门控心肌显像评价重组腺病毒-肝细胞生长因子治疗缺血性心脏病

目的 探讨99Tcm-甲氧基异丁基异腈(MIBI)静息门控心肌灌注显像(G-MPI)评价重组腺病毒-肝细胞生长因子(Ad-HGF)心肌内直接注射对缺血性心脏病早期治疗的价值.方法 18例冠心病患者根据随机分组表分为小、中、大剂量Ad-HGF治疗组,分别接受5×108,1.5×109,5×109空斑形成单位(PFU)/点(均分10点注射)的Ad-HGF心肌内直接注射.所有患者于治疗前后分别行静息G-MPI,以评价心功能和注射部位心肌血流灌注的变化.采用Stata 7.0软件进行统计学处理.结果 (1)与治疗前相比,小剂量组中有3例、中剂量组中有5例、大剂量组中有6例患者于Ad-HGF注射区域出现心肌血流灌注的改善,改善情况与注射剂量有量-效关系(X2=4.34, P＜0.05).(2)18例患者治疗前静息左心室射血分数(LVEF)、左心室舒张末期容积(EDV)和收缩末期容积(ESV)分别为(50.1±6.4)%,(137.7±33.2)和(70.2±22.4)ml;治疗后分别为(58.7±5.6)%,(123.7±32.7)和(51.9±14.9)ml.LVEF治疗后较治疗前有增加(t=6.1, P＜0.01),EDV和ESV则明显降低(t值分别为5.9,6.4,P均＜0.01).(3)低、中、高剂量Ad-HGF治疗组治疗前LVEF为(50.3±4.9)%,(52.0±5.4)%和(47.8±8.8)%,治疗后LVEF为(54.7±4.1)%,(58.8±3.9)%和(62.5±6.3)%.治疗前后LVEF的差值分别为(4.3±1.2)%,(6.8±5.7)%和(8.6±5.9)%,各组治疗后LVEF均增加:其中高剂量组的增加幅度明显高于中、低剂量组(t=3.3, P＜0.05; t=4.3, P＜0.01),中、低剂量组之间差异无统计学意义(t=1.1, P＞0.05).治疗前后LVEF的变化幅度与注射Ad-HGF剂量有量-效关系(Spearman相关系数为0.67, P＜0.01).结论 G-MPI可用于评价Ad-HGF心肌内直接注射治疗缺血性心脏病早期疗效.     

冠心病患者PTCA术前后核素心脏显像结果对比分析

目的　应用99Tcm 甲氧基异丁基异腈心肌灌注断层显像及心室显像随访经皮冠状动脉腔内成形术 (PTCA)及支架置入术后的效果。方法　患者在成功的PTCA及支架置入术前及随访期进行负荷 /静息或静息 /含硝酸甘油心肌灌注断层显像及心室显像检查。结果　 44例患者在术前及术后平均 11.4个月进行了心肌灌注断层显像 ,其中 40例患者进行了心室显像。结果显示 ,术后患者心肌缺血及不可逆缺损节段数减少 ,分别为 2 .5± 0 .4与 1.5± 0 .3(P =0 .0 6 )及 3.5± 0 .5与 2 .3± 0 .4(P <0 .0 5 ) ;左室射血分数、高峰射血率及高峰充盈率无明显变化 ,运动低下节段数有所下降 ,但未达到统计学差异。结论　成功的PTCA及支架置入术后心肌缺血明显改善 ,左室功能无明显变化 ,部分节段运动改善     

99Tcm-NOET门控心肌灌注SPECT评价冠心病的价值

目的评价99Tcm--双（N-乙氧基,N-乙基-二硫代氨基甲酸酯）氮化锝（99Tcm-NOET）静息门控断层心肌灌注显像对冠心病患者的诊断价值。方法疑诊为冠心病的45例患者注射925MBq 99Tcm-NOET后1h用SPECT行静息门控心肌灌注显像,获得舒张未期容积（EDV）、收缩未期容积（ESV）、左室射血分数（LVEF）等心功能参数和舒张末期容积灌注、局部射血分数、局部室壁活动和室壁增厚度4个靶心图。所有患者在1周内行冠状动脉造影,将冠状动脉狭窄≥50％定为病变血管。根据冠状动脉造影结果将其分为心肌梗死组、心肌缺血组和对照组三组。结果99Tcm-NOET静息门控SPECT诊断冠心病的灵敏度和特异度分别为68．42％和83．33％。心肌梗死组的心功能参数[EDV=（129．32±9．14）ml,ESV=（80．97±9．49）ml,LVEF=（40．15±3．28）％】与对照组【EDV=（80．91±3．12）ml,ESV=（30．12±1．79）ml,LVEF=（63．51±1．04）％]相比,统计学差异有显著性（EDV：F=22．103,ESV：F=32．277,LVEF：F=42．60：4,均为P〈0．01）,心肌缺血组的心功能参数[（EDV=（70．83±3．46）ml,ESV=（25．13±2．85）ml,LVEF=（65．55±2．62）％1与对照组相比,统计学差异无显著性意义。心肌梗死组左室心肌共分为460个节段,其中209个节段局部灌注、局部射血分数、局部室壁活动和室壁增厚度4个靶心图均异常。局部灌注异常的节段共328个节段,伴有局部射血分数、局部室壁活动和室壁增厚度异常分别有250个、240个和276个节段。局部灌注异常的节段与局部射血分数、局部室壁活动和室壁增厚度异常的节段不完全匹配。结论99Tcm-NOET静息门控心肌灌注显像对冠心病的诊断有较大临床应用价值,所获得的整体心室功能参数在心肌梗死的评价中有优越性,但对心肌缺血的诊断价值不大。心肌梗死中存在有不少的局部灌注与心肌?     

静息门控心肌显像评价冠心病患者CABG术后早期疗效

目的应用^99Tc^m-甲氧基异丁基异腈（MIBI）心肌灌注及心室显像评价冠状动脉旁路移植（CABG）术的近期疗效。方法对52例接受CABG术的患者于手术前1周、术后3～5周分别行静息心肌灌注及心室显像，采用QGSPECT专用软件程序定量分析整体及局部心室功能，并与超声心动图检查结果进行比较。结果①术后^99Tc^m-MIBI显像示左室射血分数（LVEF）提高（P〈0．05），左室舒张末期容积（EDV）、收缩末期容积（ESV）均明显减小（P〈0．001），与超声心动图检查示EDV、ESV变化结果符合。②手术前后LVEF改变值与整体室壁运动（WM）改变值（r=0．75，P〈0．01）及整体室壁收缩增厚率（WT）改变值（r=0．51，P〈0．01）均有良好相关性；手术前后整体-12,肌血流灌注值与整体WM值（r=0．54、0．36，P均〈0．01）及整体WT值（r=0．63、0．65，P均〈0．01）均有较好的相关性。③术后心肌显像剂相对摄取值提示前壁、间隔、下壁多节段心肌灌注明显改善（P〈0．05）。④术后显像提示前壁、间隔的WM降低（P〈0．05），下壁、前侧壁、下侧壁WM明显改善（P〈0．05），并与超声心动图结果基本符合；WT仅下侧壁明显改善（P〈0．05），在间隔无变化（P〉0．05）。结论CABG术后心肌显像的WM低估间隔室壁运动，高估侧壁运动；WT与心肌血流灌注在手术前后均有较好的相关性，可能更适用于评价CABG术后心功能。     

The additive value of gated SPET myocardial perfusion imaging in patients with known and suspected coronary artery disease

In myocardial perfusion scintigraphy, the clinical significance of fixed defects presents some difficulty. In this study, we evaluated whether additional information on left ventricular function assessed by quantitative gated single-photon emission computed tomography (gated SPET) would increase the diagnostic yield of the study in such patients. We studied 55 patients with a previous myocardial infarction and 20 patients without a previous myocardial infarction using gated SPET 99Tc(m)-tetrofosmin myocardial perfusion imaging. Each patient had to have a persistent perfusion defect consisting of at least three contiguous segments in the same vascular territory. The left ventricle was divided into 20 segments which were analysed for perfusion and wall thickening on a 4-point severity scale. Of the 55 patients with myocardial infarction, 19 (35%) patients showed preserved wall thickening in the region of the previous infarction with fixed perfusion abnormalities, which suggested residual myocardial viability. In the 20 patients without myocardial infarction, preserved wall thickening was seen in 10 (50%) patients with fixed perfusion defects, suggesting an attenuation artefact. Conversely, in 16 (29%) patients in the myocardial infarction group and two (10%) patients in the non-myocardial infarction group normal perfusion was associated with severely diminished wall thickening possibly due to stunning. We found an excellent correlation between wall thickening and left ventricular ejection fraction both for the patients with myocardial infarction and the patients without myocardial infarction (r = 0.86 and r = 0.82, respectively, both P<0.0001). A reasonable correlation between perfusion and left ventricular ejection fraction was found for the patients with myocardial infarction (r = 0.41, P = 0.002), and a non-significant correlation for the patients without myocardial infarction (r = 0.37, P = 0.1). Quantitative gated SPET myocardial imaging allows the detection of residual wall thickening in patients with a previous myocardial infarction who show severe fixed perfusion defects. In patients without myocardial infarction, gated SPET imaging allows differentiation between an attenuation artefact and a fixed perfusion defect due to coronary artery disease. In addition, gated SPET may show diminished ventricular function in normally perfused segments possibly due to myocardial stunning. The addition of gated SPET myocardial perfusion imaging increases diagnostic confidence and may have direct clinical implications for optimal patient management.     

放射性核素心肌灌注显像在急性冠状动脉综合征中的临床应用

近年来,急性冠状动脉综合征(ACS)在临床上越来越受到重视。应用放射性核素心肌灌注显像(MPI)可以对常规方法不能明确诊断的急性胸痛患者排除或确诊ACS作出迅速、准确判断,其诊断的灵敏度和阴性预测值均很高。MPI还有助于评价心肌缺血和梗死灶的范围和程度,对ACS患者进行危险分层,为ACS的预后判断和疗效评估提供重要信息。     

Assessment of cardiac function in patients with heart disease by quantitative gated myocardial perfusion SPECT

Objective We examined the cardiac function of patients who underwent Tc-99m sestamibi quantitative gated myocardial single photon emission computed tomography with 16-framing data acquisition between January 1, 2004 and March 31, 2006 for an evaluation of suspected or known heart disease in our hospital. Methods In 192 patients aged ≥40 years, the left ventricular (LV) systolic function [parameter: ejection fraction (EF)] and diastolic function [first third filling fraction (1/3FF), peak filling rate (PFR), and time-to-peak filling (TPF)] were estimated by volume curve analysis. In 51 (age ≥60 years) of 192 patients, brachial-ankle pulse wave velocity (baPWV) was also measured. Results The correlation between diastolic parameters PFR and 1/3FF was mild (r = 0.28, P < 0.001). On the basis of EF and PFR, 192 patients were divided into four groups: P (preserved LV function), Q (isolated systolic dysfunction, EF < 50%), R (isolated diastolic dysfunction, PFR < 1.8 EDV/s), and S (both dysfunctions). The numbers of patients in P, Q, R, and S groups were 94 (49.0%), 7 (3.6%), 31 (16.1%), and 60 (31.3%), respectively. The 1/3FF correlated weakly but significantly with age (r = −0.16, P < 0.05). The TPF also correlated weakly with age (r = 0.25, P < 0.01), but EF did not. The baPWV, an indicator of cardiovascular stiffness, correlated inversely with 1/3FF (r = −0.59, P < 0.001) or correlated positively with TPF (r = 0.45, P < 0.001), but not with EF. Conclusions Our study suggests that cardiovascular stiffness associated with increased baPWV may contribute to the occurrence of diastolic dysfunction in elderly patients.     

肌聚糖病的99Tc^m—MIBI门控心肌灌注断层显像评价

目的探讨99Tc^m一MIBIG—MPI评价肌聚糖病患者心肌受损的价值。方法临床、分子病理确诊的肌聚糖病患者8例（男3例,女5例,年龄10—30岁）、对照者4名均接受99TcmMIBIG—MPI。原始数据按常规处理成断层图像,再应用定量门控分析软件（QGS）进行左室功能定量分析。采用将左心室分为7个节段、20个亚段的5分制（0—4分）半定量方法,用于评估心肌受损的程度。结果8例患者99Tcm-MIBIG—MPI阳性7例。7例阳性患者140个心肌亚段中共检出59个亚段异常。按病变累及室壁节段（7个节段）分为：单一室壁节段异常1例,2个室壁节段异常2例,3个及3个以上室壁节段异常、病灶呈散在性分布4例。8例肌聚糖患者中5例患者左心室扩大,其中3例左室射血分数为（43．1±2．8）％。结论99Tcm-MIBIG—MPI能直观探测肌聚糖病患者的心肌损害,可作为肌聚糖病患者心肌损害早期诊断和远期随访的辅助诊断方法。