Effect of Coronary Artery Stenosis on the Transmural Extent of the Rest Myocardial Perfusion of Different Segments of Left Ventricular Wall Using 640 Slices CT

目的 确定静息态下透壁心肌灌注指数(TPR)的正常值,并探讨静息态下不同分支的冠状动脉狭窄与各冠状动脉分支的不同狭窄程度对左室壁不同节段TPR的影响.方法 274例患者行Toshiba 640层CT检查,包括冠状动脉CTA及左心室室壁CT灌注(CTP)检查.根据冠状动脉狭窄程度及17节段进行分组.计算正常组及不同冠状动脉狭窄程度组之间相应节段内TPR是否存在差异,以及冠状动脉狭窄程度与相应节段TPR的相关性.结果 前降支及左旋支病变对于左室壁心肌灌注影响较为明显,前降支狭窄主要影响中间段前壁(r=-0.288)、心尖段前壁(r=-0.263)及中间段间隔壁(r=-0.196),左旋支主要影响基底部前侧壁(r=-0.241)、基底部后侧壁(r=-0.279)及心尖段侧壁(r=-0.201),而右冠状动脉病变影响较小,主要影响中间段后壁(r=-0.195);冠状动脉中、重度狭窄组对于左室壁心肌灌注影响程度较大(P＜0.05),轻度狭窄影响较小;左室前壁心肌灌注最易受到冠状动脉狭窄影响;在静息状态下前降支供血区域组、左旋支供血区域组及右冠状动脉供血区域组正常心肌和重度狭窄心肌平均TPR值分别为1.14±0.09和1.07±0.13、1.13±0.11和1.06±0.14、1.15±0.14和1.10±0.12.结论 不同冠状动脉分支狭窄分别可以影响不同节段的心肌透壁灌注;不同冠状动脉狭窄程度可以不同程度地影响心肌的TPR,二者具有相关性;静息状态下TPR正常值大于负荷状态下TPR.本研究提供了TPR静息态下的正常值.     

静息态下左前降支肌桥对透壁心肌灌注影响的640层CT研究

目的 探讨静息态下左前降支(LAD)单纯肌桥及其伴随的近端动脉粥样硬化对左室壁不同节段透壁心肌灌注指数(TPR)的影响.方法 对1200例患者采用640层CT行冠状动脉CTA检查,对LAD心肌桥组121例及另外36例正常对照组行左心室壁TPR分析,对121例LAD心肌桥组根据肌桥厚度及是否伴有近端粥样硬化分为多个亚组.评价不同厚度肌桥、肌桥伴粥样硬化对于相应节段心肌TPR的影响.结果 121例LAD肌桥并发其近端粥样硬化者60例(49.6％).肌桥组与对照组中间段前壁(t=2.299)、中间段间隔壁(t=2.591)、心尖段前壁(t=2.545)及心尖段间隔壁(=2.157)TPR值差异具有统计学意义(P＜0.05).单纯深、浅肌桥组之间及其与对照组间所有节段TPR差异均无统计学意义.浅肌桥伴粥样硬化组与对照组比较,中间段前壁(t=-2.59)、中间段前间隔(t=-2.81)、心尖段前壁(t=-2.78)TPR差异有统计学意义(P＜0.05);深肌桥伴粥样硬化组与正常对照组在基底部前间隔壁(t=-3.59)、中间段前壁(t=-3.08)、中间段前间隔(t=-3.49)、心尖段前壁(t=-3.01)及心尖段室间隔(t=-2.78)TPR差异存在统计学意义(P＜0.05).LAD肌桥前粥样硬化病例的中、重度狭窄组TPR下降明显,轻度狭窄组仅影响心肌前壁.另外深肌桥组与浅肌桥伴发其近端冠状动脉粥样硬化的差异无统计学意义(x2=0.203).结论 单纯LAD肌桥对于心肌透壁灌注影响无明显临床意义;肌桥伴其近端动脉粥样硬化影响心肌灌注,主要是使前壁及心尖部心肌灌注下降,且中重度狭窄时对TPR影响更明显.     

左冠状动脉前降支重度狭窄CT血管成像的影像特征

目的 评价左冠状动脉前降支(LAD)重度狭窄CT血管成像(CTA)的影像特征.方法 回顾性分析同期行冠状动脉CT血管成像(CCTA)及选择性冠状动脉造影检查43例,LAD管腔狭窄＞70％,运用图像后处理软件在心脏短轴乳头肌层面,测量前壁、侧壁心肌CT值,结合收缩期及舒张期,测量心腔内径及节段心肌厚度,计算节段心肌收缩幅度及心肌增厚率,评价节段心肌早期灌注及心肌功能.以侧壁心肌作为对照,行单因素方差分析,P＜0.05认为有统计学差异.结果 病变位于LAD开口或近段17例(39.5％),位于近中段26例(60.5％),其中钙化斑块11例(25.6％),纤维斑块8例(18.6％),软斑块24例(55.8％).43例中,前壁心肌平均CT值(57.9±7.05) HU,41例心肌早期灌注减低(95.3％).侧壁心肌平均CT值(86.8±2.57)HU.心脏短轴乳头肌层面前壁心肌平均收缩幅度(32.2±7.75)％,侧壁心肌平均收缩幅度(46.3±4.02)％,前壁平均心肌增厚率(17.3±23.67)％,侧壁平均心肌增厚率(52.0±17.43)％.前壁心肌密度减低且伴有心肌功能减退33例.前壁与侧壁节段心肌CT值、心肌收缩幅度及节段心肌增厚率均存在显著性差异(P＜0.05).结论 CCTA能准确显示冠状动脉狭窄的部位、程度,可提供管壁斑块性质信息,冠状动脉管腔重度狭窄导致心肌早期灌注减低,且伴随相应节段心肌功能减低.     

心肌灌注显像对症状性冠状动脉心肌桥患者的临床应用价值

目的 探讨心肌灌注显像对症状性冠状动脉(以下简称冠脉)心肌桥患者的临床应用价值.方法 回顾性分析19例因胸痛、胸闷等症状行冠脉造影排除阻塞性冠脉狭窄,诊断为心肌桥并接受运动-静息99Tcm-甲氧基异丁基异腈(MIBI)心肌灌注显像的患者资料,分析心肌灌注显像结果,并与运动心电图、冠脉造影结果比较.应用Stata 7.0软件,对符合正态分布的计量资料行t检验比较,用χ2检验分析组间频数差别.结果 19例症状性心肌桥患者冠脉造影示收缩期冠脉狭窄程度为(65.4±22.1)%,18例为左前降支肌桥、1例为左前降支合并左回旋支肌桥.运动-静息心肌灌注显像示心肌缺血10例、正常9例,其中心肌缺血位于前壁和(或)心尖部8例、下壁1例、后侧壁和后间壁1例;心肌灌注显像诊断心肌缺血的阳性率为52.6%(10/19),明显高于运动心电图的21.1%(4/19)=4.07,P<0.05.19例心肌桥患者按Nobel分级法,Ⅰ级狭窄5例、Ⅲ级狭窄6例、Ⅲ级狭窄8例;Ⅰ级狭窄患者中1例心肌灌注显像心肌缺血阳性,Ⅱ级狭窄患者中2例阳性,Ⅲ级狭窄患者中7例阳性.心肌桥患者心肌灌注显像心肌缺血组收缩期冠脉狭窄明显高于心肌灌注显像正常组[(78.0±4.7)%与(52.8±6.7)%,t=3.06,P<0.01],2组肌桥长度差异无统计学意义[(15.1±2.1)mm与(11.8±1.0)mm,t=1.43,P>0.05].结论 运动-静息心肌灌注显像能有效评价症状性心肌桥患者所致心肌缺血,明确心肌桥与临床症状的关系及其临床意义.     

心脏磁共振在冠状动脉非阻塞性心肌梗死中的应用价值

【摘要】目的：探讨心脏磁共振（CMR）多序列成像在冠状动脉非阻塞性心肌梗死（MINOCA）中的应用价值。方法：筛选出临床拟诊为急性心肌梗死（AMI）并接受冠状动脉造影（CAG）或冠状动脉CTA检查,同时符合欧洲心脏病协会（ESC）诊断标准的21例MINOCA患者,所有患者在冠状动脉检查后一周内完成CMR检查。CMR检查包括心脏形态、首过心肌灌注、磁共振延迟增强（LGE）扫描。根据LGE结果分析心肌梗死节段的分布;冠状动脉狭窄程度与心肌梗死节段数的相关性。根据心肌首过灌注结果,将MINOCA患者左心室节段分为灌注缺损、灌注降低、灌注正常节段,并与LGE检测的心梗透壁程度进行对照,分析不同透壁程度与不同灌注类型间的相关性。结果：21例MINOCA患者共84个心肌节段发生心肌梗死,61.9%的心肌梗死发生于前壁、前间壁和下间壁。相对于无明显狭窄的冠状动脉,冠状动脉轻度狭窄者所支配的心肌发生MINOCA的概率更大（OR=1.924,95%CI=1.165~3.177,P=0.012）。不同灌注类型与心梗透壁程度的Kendall等级相关分析结果显示,心肌首过灌注量越低,心肌梗死透壁程度越高（等级相关系数τb=－0.819,P=0.025）。结论：MINOCA多发生于前壁及间壁;轻度狭窄的冠状动脉所支配的心肌发生MINOCA的概率更大;MINOCA患者不同的心肌灌注状态与心梗透壁程度具有显著的相关性。     

~(99)Tc~m-NOET门控心肌灌注SPECT评价冠心病的价值

目的 评价~(99)Tc~m-双(N-乙氧基,N-乙基-二硫代氨基甲酸酯)氮化锝(~(99)Tc~m-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925 MBq~(99)Tc~m-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 ~(99)Tc~m-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=42.604,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)%]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 ~(99)Tc~m-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室壁功能异常节段的不匹配,对心肌存活的评价有帮助.     

双源CTA评价非ST段抬高型急性冠脉综合征

目的:探讨双源CT血管成像(DSCTA)评价非ST段抬高型急性冠脉综合征(NSTE-ACS)的价值.方法:搜集临床疑似NSTE ASC且经DSCTA判断为左冠状动脉前降支管腔临界狭窄(狭窄程度为50％～70％)的患者57例,1周内行冠脉造影(CAG)证实狭窄程度,并行导管法测量血流储备分数(FFR),以FFR 0.80为临界值将57例患者分为A组(FFR＜0.80)和B组(FFR≥0.80),测量左室前壁、侧壁心肌、左心室腔CT值及舒张末期、收缩末期节段室壁厚度,比较两组间前壁与侧壁相对CT值、舒张末期心肌厚度及室壁增厚率.结果:A、B两组前壁与侧壁心肌相对CT值及舒张末期心肌厚度差异均有统计学意义(P＜0.05),A组前壁与侧壁室壁增厚率差异有统计学意义(P＜0.05),B组前壁与侧壁室壁增厚率差异无统计学意义(P＞0.05);前壁心肌相对CT值及室壁增厚率A、B两组间差异有统计学意义(P＜0.05),而舒张末期心肌厚度A、B两组间差异无统计学意义(P＞0.05).结论:DSCTA评价左冠状动脉前降支管腔临界狭窄联合节段心肌CT值、舒张末期心肌厚度及室壁增厚率分析,可为NSTE-ACS的诊断及治疗提供依据.     

心肌声学造影和二维斑点追踪成像在冠心病诊断中的应用价值

目的 分析对比冠心病患者的心肌声学造影(MCE)、二维斑点追踪成像技术(2D-STI)与冠状动脉血管造影术的结果，评价左心室心肌声学造影及2D-STI在冠心病节段室壁血流灌注异常中的应用价值。方法 选取本院50例临床初诊为冠心病患者的心肌声学造影及2D-STI,将其分别与冠状动脉造影结果进行对照分析，评估其在室壁节段血流灌注异常的准确性与一致性。结果 50例冠心病患者经冠状动脉造影纳入血管共150支，其中40例患者经冠状动脉造影证实有单支或多支冠状动脉狭窄>50%,病变血管56支，左前降支30支，左旋支12支，右冠状动脉14支。单支病变22例，多支病变18例，冠状动脉造影正常10例。按照冠状动脉的供血范围与左心室壁17节段相对应关系入选的心肌节段共850个，冠状动脉狭窄0%～49%的心肌节段共672个，冠状动脉狭窄50%～75%的心肌节段共65个，冠状动脉狭窄76%～99%的心肌节段共103个，冠状动脉完全闭塞的心肌节段10个。MCE检出心肌灌注异常与冠状动脉狭窄≥50%的一致性为89%,2D-STI检出节段室壁运动异常与相应供血支冠状动脉狭窄≥50%的一致性为87%;以冠状动脉...     

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?     

冠状动脉CT成像与冠状动脉造影检查心肌桥一壁冠状动脉的结果差异分析

目的探讨冠状动脉CT成像与冠状动脉造影检查心肌桥-壁冠状动脉的效果。方法选择我院收治的426例疑似心肌桥-壁冠状动脉患者,先后实施冠状动脉CT成像与冠状动脉造影检查,比较分析两者检查心肌桥-壁冠状动脉的结果差异。结果经CTA检查显示,50例患者(占比11.74%)合计存在61段心肌桥-壁冠状动脉:处于左前降支为52段,处于对角支为2段,处于左回旋支为5段,处于右冠状动脉为2段;其中属于深在型心肌桥的有21段,属于浅表型心肌桥的有40段。经CAG检查显示,43例患者中有有71段存在心肌桥-壁冠状动脉:处于左前降支为50段,处于对角支为1段,处于左回旋支为4段;其中属于深在型心肌桥21段,属于浅表型心肌桥37段。CTA与CAG检查深在型心肌桥(Kappa=1.000)和浅表型心肌桥(Kappa=0.868)的结果Kappa检验一致性好。CTA测量出来的深在型与表浅型心肌桥之长度均多于CAG所测量出来的长度(P0.05),但是CAG测量出来的壁冠状动脉狭窄程度则多于CTA测量出来的狭窄程度(P0.05)。结论在深在型与表浅型心肌桥-壁冠状动脉存在与心肌桥长度的测量方面,CTA检查优于CAG,但是在壁冠状动脉狭窄程度的测量方面则相反。     

Cardiac MRI in ischemic heart disease with severe coronary artery stenosis

RATIONALE AND OBJECTIVES: The aim was to evaluate the left ventricular wall motion abnormalities, perfusion and late contrast enhancement patterns on magnetic resonance imaging (MRI) in patients with 70% or higher degree stenosis or occlusion of coronary arteries on coronary angiography. MATERIALS AND METHODS: Twenty-four patients (5 women, 19 men, age range 38-78, mean age 59.1) who had 70% or higher degree stenosis or occlusion of coronary arteries on coronary angiography who had been referred for cardiac MRI were included. On coronary angiography, 20 vessels were totally occluded [left anterior descending artery (LAD) 12; left circumflex coronary artery (LCx) 2; right coronary artery 6] and 20 vessels were severely stenotic (70-99%). In 5 patients' three vessels, in 6 patients' two vessels, and in 13 patients' a single vessel was involved. Wall motion, perfusion abnormalities, and late contrast enhancement consistent with nonviable myocardium were analyzed at apical, at midventricular, and basal levels on short-axis images of cardiac MRI in concordance with the segmental irrigation areas of the coronary arteries. RESULTS: Impaired perfusion was observed on the corresponding irrigation segments of 39 vessels of 40 coronary artery branches. Wall motion abnormalities were present on corresponding irrigation areas of 30 severely stenotic vessels. Combined evaluation of wall motion and perfusion, segments with the decreased left ventricular contraction, and perfusion matched with the corresponding irrigation areas of all of the 40 stenotic or occluded vessels. CONCLUSION: A correlation was found between the combined assessments of myocardial perfusion, wall motion, and viability on late contrast enhancement on cardiac MRI with the clinical and angiography findings. Thus this combined MRI protocol can be used for the evaluation of ischemic heart disease.     

Assessment of regional differences in myocardial blood flow using T2-weighted 3D BOLD imaging.

The feasibility of detecting regional differences in myocardial blood flow based on the blood oxygen level-dependent (BOLD) effect was evaluated in vivo in dogs (N = 9) using a 3D T2-prepared segmented gradient-echo sequence at 1.5 T. Regional differences in myocardial blood flow were created by administering adenosine through a catheter placed in the left circumflex coronary artery (LCX). The difference in the R2 (1/T2) relaxation rate between the left ventricular myocardial region supplied by the LCX and regions supplied by the left anterior descending coronary artery (LAD) or septal artery during adenosine administration was correlated to the corresponding regional myocardial blood flow difference determined using fluorescent microspheres. A correlation coefficient of 0.80 was found between the MR BOLD measurements and the myocardial flow assessment. Our results show that the sequence used in this study allows fast 3D BOLD imaging of the heart, and is a promising technique for detecting regional myocardial perfusion differences.     

Severe regional ischemia alters coronary flow reserve in the remote perfusion area

BACKGROUND: Clinical and experimental studies suggest that coronary flow reserve (CFR) may be abnormal in regions remote from myocardial infarction. We sought to determine the possible relation among stenosis severity, ischemic dysfunction, and impairment of CFR in remote regions. METHODS AND RESULTS: In 7 open-chest dogs, acute graded left circumflex (LCX) ischemia was created and maintained based on measurement of the transstenotic (aortic-distal LCX) pressure gradient (measured in millimeters of mercury). Regional thickening was assessed with sonomicrometers. Regional myocardial flow was assessed at rest with radiolabeled microspheres. Doppler flow probes were placed on proximal LCX and left anterior descending (LAD) arteries to measure resting flow and CFR in response to intracoronary injection of adenosine (36 microg). These parameters were assessed under baseline conditions and during transstenotic gradients of 10, 20, 30, and 40 mm Hg. Increasing LCX stenosis severity caused progressive impairment of LCX CFR: baseline (2.22+/-0.10), stenosis 10 (1.80+/-0.06), stenosis 20 (1.56+/-0.08), stenosis 30 (1.30+/-0.04), and stenosis 40 (1.17+/-0.06) (P<.01 vs. baseline). Remote LAD CFR was not altered by mild to moderate LCX stenosis (baseline [2.33+/-0.19]; stenosis 10 [2.30+/-0.25]; stenosis 20 [2.15+/-0.26]). However, critical LCX stenosis producing mild to moderate reduction in thickening in the ischemic region was associated with a significant impairment of LAD CFR: stenosis 30 (1.90+/-0.26) and stenosis 40 (1.80+/-0.22) (P<.01 vs. baseline). These changes in remote CFR persisted after correction for changes in the rate-pressure product. CONCLUSION: In an acute canine model of progressive LCX coronary stenosis, CFR was impaired in both ischemic and remote nonischemic regions in association with mild to moderate ischemic-induced regional myocardial dysfunction. Thus pharmacologic vasodilation provoked only mild heterogeneity in CFR in the presence of a critical LCX stenosis as a result of concurrent reduction of LAD CFR. This phenomenon warrants further clinical and experimental investigation because it may affect detection of flow heterogeneity during acute ischemia (which induced myocardial dysfunction).     

64层螺旋CT冠状动脉粥样硬化斑块稳定性分析

目的探讨64层螺旋CT冠状动脉成像在判别冠心病不同类型间斑块性质方面的价值。方法经冠状动脉造影(CAG)证实明确诊断为冠心病的患者126例,行64层螺旋CT冠状动脉成像,并对主要冠状动脉狭窄节段数、狭窄程度以及斑块性质进行比较。结果本组患者冠状动脉评估节段数368个,其中狭窄节段195个(35.4%)。狭窄<50%共98个节段,狭窄50%～75%共71个节段,狭窄>75%共26个节段(左前降支中段、近段、后降支中段、左回旋支近段),其中完全闭塞2个(右冠状动脉近段以远、左回旋支中段以远)。软斑块46个(27.3%),纤维斑块42个(31.5%),混合斑块78个(29.5%),钙化斑块93个(12.6%)。对应斑块测量的CT值分别为软斑块(17±26)HU,纤维斑块(97±35)HU,钙化斑块(489±195)HU。结论 64层螺旋CT冠状动脉成像有助于显示斑块性质。     

Accuracy of 99mTc-tetrofosmin myocardial tomography in the evaluation of coronary artery disease

BACKGROUND: Technetium 99m-labeled myocardial agents have been proposed as an alternative to thallium 201. The aim of this study was to assess retrospectively the accuracy of exercise myocardial 99mTc-tetrofosmin scintigraphy with tomographic imaging (SPECT) in a large group population in the evaluation of coronary artery disease. Furthermore we evaluated the relation between the severity of scintigraphic impaired myocardial perfusion and the angiographic coronary artery stenoses in patients without myocardial infarction and with stenosis localized exclusively in the proximal segment of the 3 main coronary arteries. METHODS AND RESULTS: The study group consisted of 235 consecutive patients, 204 (87%) of whom were men, with a mean age of 57+/-10 years, and with suspected or known coronary artery disease, who underwent 99mTc-tetrofosmin SPECT and coronary angiography. Furthermore, 61 patients in a low-likelihood group for coronary artery disease were also studied. Significant disease was defined by > or = 50% luminal coronary artery stenosis in > or = 1 native coronary artery or major branch or in a saphenous vein graft or arterial mammary graft. The overall sensitivity was 95%, specificity was 76%, and predictive accuracy was 95%. The normalcy rate for the low-likelihood group was 93%. Sensitivity was 71% for the left anterior descending artery, 61% for the left circumflex artery, and 73% for the right coronary artery. Specificity was 94% for the left anterior descending artery, 96% for the left circumflex artery, and 91% for the right coronary artery. Predictive accuracy was 79% for the left anterior descending artery, 78% for the left circumflex artery, and 81 % for the right coronary artery. In patients without myocardial infarction linear regression analysis between scintigraphy and angiography showed a significant correlation in patients with severe proximal coronary artery stenosis (r = 0.53, P < .002), but not in those with moderate proximal stenosis (r = 0.31, P = NS). CONCLUSIONS: This study shows that 99mTc-tetrofosmin SPECT is accurate in the detection of coronary artery disease. The relation of the severity of scintigraphic impaired myocardial perfusion and angiographic coronary artery stenosis, however, may differ significantly in patients with proximal stenosis of different severity.     

Right ventricular function in healed myocardial infarction in man. A cineangiographic assessment

To evaluate the frequency of right ventricular dysfunction following recovery from myocardial infarction (MI) and the relationship of segmental right ventricular (RV) wall motion abnormalities to left ventricular (LV) function or location of coronary arterial stenosis, biplane right and left ventricular cineangiograms were obtained in 100 consecutive patients (4 +/- 3 months post MI). Thirty (group A) had anterior MI and significant stenosis or obstruction of left anterior descending artery (LAD). The remaining 70 patients had inferior MI. They were divided into three groups according to the site of the main coronary stenosis or obstruction and corresponding LV akinesia: right coronary artery (RCA) proximal to the acute marginal artery (RMA), (group B: 32 patients), RCA distal to the RMA (group C: 18 patients), left circumflex artery (LCF), (group D: 18 patients). RV and LV end-diastolic volume index (EDV), end-systolic volume index (ESV), stroke volume (SV) and ejection fraction (EF) have been determined. RV segmental wall motion was assessed in RAO and LAO projection by determining the percentage of systolic shortening (+ delta R) along 11 hemiaxes. Mean axial shortening (delta R) of the RV inferior and free walls were considered. When compared with that in 10 normal subjects, RV end-diastolic volume (RVEDV), RV end-systolic volume (RVESV) were increased and RV ejection fraction (RVEF) was lower in patients with anterior or inferior MI. Inferior delta R exhibited comparable sequential changes in the three groups of inferior MI and similar LVEF alteration.(ABSTRACT TRUNCATED AT 250 WORDS)     

Cardiac adrenergic innervation is affected in asymptomatic subjects with very early stage of coronary artery disease.

The aim of this study was to investigate whether, in subjects with a very early stage of coronary artery disease without hemodynamically significant coronary artery stenoses, cardiac adrenergic innervation is already affected. METHODS: Quantitative coronary angiography and dual-isotope SPECT with 123I-metaiodobenzylguanidine (MIBG) and 99mTc-sestamibi (MIBI) were conducted to assess the function of cardiac adrenergic innervation and myocardial perfusion, respectively, in 30 asymptomatic volunteers with a high familial risk for coronary artery disease. Regional quantitative analysis of MIBG uptake and washout rates was performed using the SPECT data from the anteroseptal, lateral, and inferior myocardial regions, which represented vascular supply by the left anterior descending coronary artery (LAD), left circumflex coronary artery (LCX), and right coronary artery (RCA), respectively. RESULTS: The average severity of stenoses was 33% +/- 11% in the LAD, 29% +/- 14% in the LCX, and 26% +/- 19% in the RCA. The severity of stenosis was not related to MIBI uptake in any corresponding myocardial region at rest or during exercise. However, the degree of LAD stenosis correlated directly with delayed MIBG uptake (r = 0.43; P < 0.05) and inversely with MIBG washout (r = -0.34; P = 0.06) of the anteroseptal myocardium. When subjects were divided into tertiles according to the separate severity of stenosis for each coronary artery, delayed MIBG uptake in the anteroseptal region was significantly lower in the lowest LAD tertile (0.34 +/- 0.05) than in the middle (0.41 +/- 0.06; P < 0.01) or highest (0.43 +/- 0.05; P < 0.001) LAD tertile. Correspondingly, delayed MIBG uptake in the lateral region was also lower in the lowest LCX tertile than in the middle tertile (0.34 +/- 0.04 vs. 0.41 +/- 0.06, respectively; P < 0.01). Washout rate was also higher in the lowest LAD tertile (44% +/- 7%) than in the middle (36% +/- 10%; P < 0.05) or highest LAD tertile (34% +/- 8%; P < 0.01). CONCLUSION: The degree of coronary artery stenosis was associated directly with MIBG uptake and inversely with MIBG washout. This finding suggests that the function of cardiac adrenergic nerve endings is modified even in mild coronary artery disease before denervation occurs.     

Videodensitometric analysis of coronary stenoses. In vivo geometric and physiologic validation in humans

Assessment of the severity of coronary stenoses on arteriograms conventionally is based on subjective estimates of percent luminal diameter narrowing. However, in studies in patients with multivessel coronary artery disease, we have found a poor correlation between percent stenosis and the physiologic significance of an individual coronary obstruction. The purpose of this study was to determine whether computerized videodensitometry would allow estimation of coronary luminal area and therefore prediction of the physiologic significance of individual coronary stenoses in humans. Videodensitometry was used to define the minimal luminal area of 15 left anterior descending, 15 circumflex, and 15 right coronary artery segments in 43 patients. Computer-assisted quantitative coronary arteriography (method of Brown et al) was used to determine the minimal luminal cross-sectional area of these same segments. In each arterial segment, coronary vasodilator reserve was assessed using intraoperative (n = 18 segments) or intracoronary (n = 27 segments) Doppler measurements of coronary vasodilator reserve. Videodensitometric estimates of coronary luminal area correlated well with minimal luminal area defined using the independent geometric technique of quantitative coronary arteriography (r = 0.82, y = 0.97 X + 0.71, SEE = 1.83 mm2, n = 45) and with lesion physiologic significance as defined by studies of the peak-to-resting velocity ratio (r = 0.71, 0.92, and 0.74 for the left anterior descending, circumflex, and right coronary arteries, respectively). Thus, videodensitometry is a promising method that may supplement geometric approaches to quantitative analysis of coronary arteriograms in humans.     

Whole-heart steady-state free precession coronary artery magnetic resonance angiography.

Current implementations of coronary artery magnetic resonance angiography (MRA) suffer from limited coverage of the coronary arterial system. Whole-heart coronary MRA was implemented based on a free-breathing steady-state free-precession (SSFP) technique with magnetization preparation. The technique was compared to a similar implementation of conventional, thin-slab coronary MRA in 12 normal volunteers. Three thin-slab volumes were prescribed: 1) a transverse slab, covering the left main (LM) artery and proximal segments of the left anterior ascending (LAD) and left circumflex (LCX) coronary arteries; 2) a double-oblique slab covering the right coronary artery (RCA); and 3) a double-oblique slab covering the proximal and distal segments of the LCX. The whole-heart data set was reformatted in identical orientations. Visible vessel length, vessel sharpness, and vessel diameter were determined and compared separately for each vessel. Whole-heart coronary MRA visualized LM/LAD (11.7 +/- 3.4 cm) and LCX (6.9 +/- 3.6 cm) over a significantly longer distance than the transverse volume (LM/LAD, 6.1 +/- 1.1 cm, P < 0.001; LCX, 4.2 +/- 1.2 cm, P < 0.05). Improvements in visible vessel length for RCA and LCX in the whole-heart approach vs. their respective targeted volumes were not significant. It is concluded that the whole-heart coronary MRA technique improves visible vessel length and facilitates high-quality coronary MRA of the complete coronary artery tree in a single measurement.