急性高血糖犬心表冠状动脉和心肌微血管储备功能的实验研究

目的　探讨急性高血糖对犬心表大冠状动脉和心肌微血管血流量和血流储备的影响。方法　静注双嘧达莫前后 ,应用血流仪和心肌对比超声心动图 (MCE)测量犬基础状态和高血糖状态时冠状动脉前降支和心肌微血管的血流量。结果　应用双嘧达莫前 ,基础状态和高血糖状态的前降支和心肌微血管的血流量 ( 13 .94± 2 .92比 15 .0 5± 8.61ml/min和 45 .49± 14 .2 8比 48.62± 2 9.5 9,P >0 .0 5 )以及微血管密度 ( 5 7.0 5± 7.87比 68.65± 10 .0 0 ,P >0 .0 5 )均无差异 ;应用双嘧达莫后 ,前降支血流量和血流储备无明显变化 ,而心肌微血管的血流量 ( 91.71± 42 .67比 41.16± 2 3 .15 ,P <0 .0 1)、血流储备 ( 2 .15± 1.3 0比 0 .84± 0 .44 ,P <0 .0 5 )和血管密度 ( 86.78± 2 1.84比65 .18± 2 8.5 8,P <0 .0 5 )明显下降。结论　急性高血糖减少双嘧达莫负荷后的心肌微血管的血流量、血流储备和血管密度     

经导管急性微血管栓塞对冠状动脉血流和冠状动脉血流储备的影响

目的　建立经导管的急性微血管栓塞动物模型 ,研究不同微栓塞水平冠状动脉血流(CBF)和冠状动脉血流储备 (CFR)的变化。方法　 10头小型猪 (2 1～ 2 5kg) ,不开胸经导管由前降支重复注入微栓塞球 (4 5 μm) ,使用多普勒导丝、压力导丝和腔内超声导管测量前降支中段平均流速、压力和腔内面积 ,CBF =平均流速×面积。冠状动脉内注射腺苷 18μg达到最大充血状态 ,CFR =充血CBF 基础CBF。在微栓塞前、注入 5万、10万、12万、14万和 15万微栓塞球时分别测量基础状态和充血状态的血流动力学指标。结果　注入 5万微球时基础CBF(rCBF)升高 ,较微栓塞前差异有显著性[(0 30± 0 0 9)ml·s- 1 vs (0 2 6± 0 10 )ml·s- 1 ,P <0 0 5 ],随着微球量的增加rCBF降低。CFR在微栓塞后降低 ,不同微栓塞水平的CFR与微栓塞前比较差异均有显著性。结论　经导管急性微血管栓塞中 ,随着微栓塞球量增加 ,rCBF呈现先增加后下降的双期改变 ;微栓塞后CFR下降 ,CFR在一定微栓塞程度时又有增加。     

硝酸甘油对狗的心表冠状动脉和心肌微循环血流的影响

目的：探讨硝酸甘油(NTG)对狗心表冠状动脉和心肌微血管血流量的影响。方法：对10只雄性杂种狗静脉注射NTG后,应用心肌对比超声心动图测量心肌微血管血流量,动脉血流仪测量冠状动脉前降支血流量,超声心动图测量心脏腔径和容积。结果：NTG对心表冠状动脉和心肌微血管的血流量均无明显影响,注射NTG前后,前降支血流量为(13．91±2．91)ml/min对(14．59±4,63m)1/min；A·β值为：45．57±14．27对80．13±36．63,P均＞0．05；NTG对心率、血压、平均动脉压、中心静脉压和冠状动脉血管阻力也无明显影响。但可明显减少心脏腔径和心腔容积,尤其右心腔径和容积减少更明显；与舒张末期容积比较,NTG对心脏收缩末期容积影响更大。结论：NTG对狗的心表大冠状动脉和心肌微血管的血流量无影响,其抗心绞痛的作用可能是通过减少心脏容积和心室壁张力,减少心肌耗氧量而实现的。     

硝酸甘油对狗的心表冠状动脉和心肌微循环血流的影响

目的:探讨硝酸甘油(NTG)对狗心表冠状动脉和心肌微血管血流量的影响.方法:对10只雄性杂种狗静脉注射NTG后,应用心肌对比超声心动图测量心肌微血管血流量,动脉血流仪测量冠状动脉前降支血流量,超声心动图测量心脏腔径和容积.结果:NTG对心表冠状动脉和心肌微血管的血流量均无明显影响,注射NTG前后,前降支血流量为(13.91±2.91)ml/min对(14.59±4.63m)l/min;A·β值为:45.57±14.27对80.13±36.63,P均＞0.05;NTG对心率、血压、平均动脉压、中心静脉压和冠状动脉血管阻力也无明显影响.但可明显减少心脏腔径和心腔容积,尤其右心腔径和容积减少更明显;与舒张末期容积比较,NTG对心脏收缩末期容积影响更大.结论:NTG对狗的心表大冠状动脉和心肌微血管的血流量无影响,其抗心绞痛的作用可能是通过减少心脏容积和心室壁张力,减少心肌耗氧量而实现的.     

核素心肌灌注显像血流定量技术在冠状动脉微血管功能障碍中的应用进展

冠状动脉微血管功能障碍(CMD)广泛存在于包括冠心病在内的多种心血管疾病中。核素心肌灌注显像血流定量技术,包括正电子发射断层成像(PET)和单光子发射计算机断层成像(SPECT),可无创测定心肌血流量和冠状动脉血流储备用于CMD的评估。现就PET和SPECT血流定量分析在CMD中的应用进展进行综述。     

CZT-SPECT测定心肌血流量和血流储备对冠状动脉重度狭窄的预测价值

目的:探讨基于碲锌镉(CZT)心脏专用SPECT(CZT-SPECT)测定心肌血流量(MBF)及血流储备(CFR)对冠状动脉(冠脉)重度狭窄的预测价值。方法:回顾性分析2021年1月—2021年8月于泰达国际心血管病医院完成CZT-SPECT检查的可疑或已确诊冠心病患者129例。本研究根据患者是否存在冠脉重度狭窄病变分为缺血组和对照组(冠脉重度狭窄病变的定义标准为血管直径≥2 mm且狭窄≥70%的病变)。绘制静息MBF(rMBF)、负荷MBF(sMBF)及CFR预测冠脉重度狭窄的受试者工作特性(ROC)曲线,并根据Youden指数确定截断值。结果:共纳入129例患者,平均年龄为(60.3±9.6)岁,男性占比51.2%,单支病变患者33例(25.6%),双支病变患者22例(17.1%),三支病变患者18例(13.9%)。分别在血管水平和患者水平进行分析,结果显示缺血组rMBF、sMBF、CFR均明显低于对照组(P<0.01),其中sMBF差异最为明显。绘制rMBF、sMBF、CFR预测冠脉重度狭窄的ROC曲线,结果显示rMBF、sMBF、CFR预测冠脉重度狭窄的AUC分别为0.6...     

冠状动脉微血管病患者的三支冠状动脉血流储备的差异

目的 :观察冠状动脉 (冠脉 )造影正常而有冠脉微血管病基础者的三支冠脉血流储备 (Coronaryflowreserve ,CFR)之间是否有差异。方法 :临床上有不典型胸闷或胸痛的患者 4 5例 ,冠脉造影及左室射血分数正常 ,按有无冠脉微血管病基础分为甲、乙两组。甲组为冠脉微血管病组 ,共 2 9例 ,男 19例 ,女 10例 ,年龄 37～ 78(5 8±9.9)岁 ,其中心电图有左室肥厚或劳损表现的高血压患者 11例 ,糖尿病 3例 ,肥厚型心肌病 2例 ,长期吸烟者 10例 ,高血脂 8例 ;乙组为无冠脉微血管病组 ,共 16例 ,男 11例 ,女 5例 ,年龄 38～ 5 8(5 1± 8.6 )岁。冠脉造影过程中随机测定冠脉CFR值 (甲组 6 2支 ,左冠脉前降支 2 4支 ,冠脉左旋支 17支 ,右冠脉 2 1支 ;乙组 36支 ,左冠脉前降支13支 ,冠脉左旋支 8支 ,右冠脉 14支 )。结果 :甲组 6 2支冠脉的平均CFR为 2 .32± 0 .6 1,乙组 3.15± 0 .5 5 ,P <0 .0 1。甲组三支冠脉之间的CFR差异有统计学意义 ,P <0 .0 1;乙组三支冠脉的CFR差别无统计学意义P >0 .0 5。甲组前降支的CFR远低于右冠脉与回旋支 (2 .0 4± 0 .5 2∶2 .5 9± 0 .6 5 ,2 .39± 0 .5 5 ,均 P<0 .0 5 ) ;回旋支较右冠脉的CFR低 ,但差异无统计学意义 (2 .39± 0 .5 5∶2 .5 9± 0 .6 5 ,P >0 .0 5 )。结论 :冠脉微血     

实验性顿抑心肌微血管结构和功能改变

目的 探讨心肌顿抑时心肌微血管结构和功能改变。方法 制备冠状动脉左前降支（LAD）不同阻断时间（15min和60min)后再灌注犬心肌顿抑模型，在不同观察时间点静脉注射含全氟丙烷声振白蛋白微泡造影剂，采用二次谐波成像和间歇发射技术行心肌声学造影。由主动脉根部分别注射乙酰胆碱（ACH）和硝酸甘油（NG）后重复心肌声学造影，并计算用药后／前二维超声上所示心肌灰阶峰值比值（PVIR）和顿抑区与正常区心肌灰阶峰值比值的比值PVIRR。心肌标本行透射电镜检查。结果 （1）LAD阻断15min组再灌注早期NG－PVIR和ACH－PVIR明显减低，但分别在再灌注60min和120min时恢复至结扎前水平；（2）LAD阻断60min组再灌注早期NG－PVIR减低，至再灌注120min时才恢复到结扎前水平，而再灌注ACH-PVIR明显减低，随着再灌注时间的延长虽有逐渐回升趋势，但至再灌注120min仍未恢复至结扎前水平；（3）两组PVIRR的变化与PVIR一致，唯恢复稍慢；（4）LAD阻断15min组心肌毛细血管和内皮细胞结构未见明显改变，而LAD阻断60min组毛细血管内皮细胞肿胀，内皮细胞间连接间隙稍增宽。结论 顿抑心肌微血管舒张功能受损，缺血时间较长则还有微血管结构改变，其受损的细胞主要是内皮细胞。     

实时心肌声学造影检测高血压心肌微血管功能

目的:通过实时心肌声学造影(MCE),检测有心绞痛症状而冠状动脉造影(CAG)正常的高血压患者心肌微血管功能. 方法:入选有心绞痛症状而CAG正常的患者12例(高血压组),心绞痛症状不典型而CAG正常的非高血压患者8例(对照组),采用声学造影剂声诺维进行实时MCE检查,分别测定静息状态和腺苷负荷后造影剂微泡达到峰值的平台期强度(A),再充盈平均速度(β)及A·β,并测定A比值、β比值和冠状动脉血流储备(CFR)值.结果:高血压组静息时反映局部心肌血容量的A值、反映局部心肌血流量的A·β值与对照组差异无统计学意义(P>0.05),而反应局部心肌血流速度的β值小于对照组(P<0.05),反应心肌血容量储备的A比值、反应心肌血流速度储备的β比值较对照组低(P<0.05),高血压组CFR低于对照组(P<0.01).结论:有心绞痛症状而CAG正常的高血压患者心肌缺血与心肌微血管密度下降、CFR减退有关,实时MCE可定量检测心肌微血管功能.     

高血压病心肌微血管功能损害的研究

目的　探讨高血压病患者是否存在心肌微血管病变以及其与疾病严重程度和心肌肥厚的关系。方法　应用心肌对比超声心动图 ,静注含氟碳气体声振白蛋白微泡造影剂 (全氟显 )后 ,采用间断谐波成像技术测量静息时和注射潘生丁后心肌的A、β和A·β值 ,并计算出A、β比值和冠脉微血管的血流储备 (CMVFR)。 结果　高血压病患者静息时的A、β和A·β值均较对照组增高 (P >0 0 5) ,而注射潘生丁后明显降低 (P <0 0 1 ) ,A、β比值以及CMVFR显著降低(P <0 0 5和 0 0 1 ) ;随着高血压病情的加重 ,A和A·β值增高 ,A比值和CMVFR下降 ,A和A·β值与SBP、DBP显著正相关 (P <0 0 1 )、CMVFR与DBP负相关 (P <0 0 5) ;高血压左室肥厚 (LVH)患者静息状态的A、β和A·β值较无肥厚者增加 ,A、β比值和CMVFR下降 ;A和A·β与LVM和LVMI显著相关 (P <0 0 1 ) ;CMVFR与室间隔厚度负相关(P <0 0 5)。结论　高血压病患者静息时的心肌微循环血流量增加、心肌微血管储备功能和非内皮依赖性的血管扩张能力明显受损、心肌毛细血管密度明显减少 ,并且随着疾病的进展而加重 ;高血压LVH患者较无LVH者的微血管功能受损程度更严重     

Regional myocardial perfusion reserve determined using myocardial perfusion magnetic resonance imaging showed a direct correlation with coronary flow velocity reserve by Doppler flow wire

Aims: Quantitative analysis of rest–stress myocardial perfusionmagnetic resonance imaging (MRI) can provide assessments ofregional myocardial perfusion reserve (MPR). The purpose ofthis study was to compare regional MPR determined by myocardialperfusion MRI with coronary flow reserve (CFR) by intracoronaryDoppler flow wire. Methods and results: Twenty patients with suspected coronary artery disease (CAD)were studied. Average peak velocity was measured by Dopplerflow wire in the resting state and during adenosine triphosphate(ATP) stress in 36 coronary arteries. CFR measurements for eachpatient were performed in the culprit and one non-culprit non-stenoticartery. First-pass, contrast-enhanced myocardial perfusion MRimages were obtained in the resting state and during ATP stresswithin the week before the Doppler wire procedure. Regionalmyocardial blood flow (MBF) was quantified in 16 myocardialsegments by analysing arterial input and myocardial output usinga Patlak plot method. MPR was calculated as stress MBF dividedby rest MBF. CFR measured by Doppler flow wire was comparedwith MPR in the myocardial segments corresponding to vesselterritories. The average MPR measured by perfusion MRI was 1.77± 0.62 for the culprit arteries and 3.45 ± 0.78for the non-culprit arteries, respectively (P < 0.001). Theaveraged CFR by Doppler flow wire was 1.72 ± 0.44 inthe culprit arteries and 3.14 ± 0.74 in the non-culpritarteries, respectively (P < 0.001). For both culprit andnon-culprit vessel groups, significant direct correlations wereobserved between MR assessments of MPR and Doppler assessmentsof CFR (culprit artery: R = 0.87, Non-culprit artery: R = 0.86)On Bland–Altman analysis, the mean differences betweenMPR determined by myocardial perfusion MRI and CFR measuredby Doppler wire were 0.05 in culprit arteries (95% limit ofagreement; –0.65 to 0.56) and 0.36 in non-culprit arteries(95% limit of agreement; –1.24 to 0.44). The sensitivityand specificity of MR measurement of MPR for predicting physiologicallysignificant reduction of Doppler CFR (<2) was 88% (95% CI61.7–98.5) and 90% (95% CI 68.3–98.8), respectively. Conclusion: The current results using Doppler flow wire as a reference methoddemonstrated that quantitative analysis of stress–restmyocardial perfusion MRI can provide a non-invasive assessmentof reduced MPR in patients with CAD.     

心肌血流储备分数在冠心病诊断及介入治疗中的应用研究进展

冠状动脉造影（CAG）是目前诊断冠心病最常用和最重要的手段,是进一步行经皮冠状动脉介入治疗（PCI）或冠脉搭桥术（CABG）的金标准。但是随着对冠脉血流动力学及病理学研究的不断深入,单纯冠脉造影提供的形态学已不能满足临床对狭窄病变解剖特征和生理功能评价的需要。     

心肌血流储备分数在急性冠状动脉综合征中的应用现状

<正>自从冠状动脉造影技术问世以来,它已经成为解剖学上评价冠状动脉病变的重要方法,以及对病变进行冠状动脉介入治疗的重要依据,然而,冠状动脉造影术并不能准确评价冠状动脉狭窄病变引起血流功能性变化。1993年,Pijls     

Effects of endothelin-1 on epicardial coronary tone,coronary blood flow,ECG-ST change and regional wall motion in anesthetized dogs

Summary The effects of intracoronaryadministrated endothelin-1 on coronary hemodynamics and regional myocardial function were studied in anesthetized open-chest dogs. Epicardial coronary diameter (CoD) and coronary blood flow (CBF) were measured by a sonomicrometer of 10 MHz piezoelectric crystals and an electromagnetic flow probe on the left circumflex coronary artery (LCX). Regional wall motion was sonomicrometrically measured at regions supplied by the LCX and left anterior descending artery (LAD) and electrocardiograms were recorded. Endothelin-1, administered as a bolus injections into the LCX via an intracoronary cannula, in a dose-dependent manner reduced COD and CBF. The extent of the reduction of COD and CBF at a dose of 300 pmol was 12.3±1.5% (P<0.01) and 86±5% (p<0.01), respectively, of the control. The extent of CBF reduction and deterioration of systolic wall motion were linearly related with the dosage of endothelin-1. ST-elevation (lead II) and fatal ECG abnormalities, including complete atrioventricular block or ventricular fibrillation, were observed with doses above 60 and 100 pmol, respectively. Coronary angiography revealed that filling defects of dye were propagated from the third or distal branches to those of more proximal arteries when the doses of endothelin-1 were cumulatively infused into the LCX. Accordingly, lethal myocardial ischemia induced by endothelin-1 is produced by critical obstruction of rather small coronary vessels.Part of the study was supported by Grants-in-Aid for Scientific Research (Nos. 02454259, 02404045) from the Ministry of Education, Science, and Culture, Japan, and a Research Grant for Cardiovascular Disease (1S-1) from the Ministry of Health and Welfare, Japan.     

血糖对急性ST段抬高心肌梗死再灌注治疗前冠状动脉血流的预测价值

目的评价急性ST段抬高心肌梗死(STEMI)患者血糖水平增高与急诊介入治疗(PCI)前患者冠状动脉TIMI血流的相关性。方法选择120例STEMI行急诊PCI治疗的患者,收集患者入院前全血血糖、PCI前冠状动脉造影梗死相关血管TIMI血流以及患者临床资料。血糖≥7·8mmol/L(140mg/dL)定义为高血糖症。结果在接受急诊PCI术前仅有18例(15%)患者冠状动脉造影血流达到TIMI3级,高血糖症患者87例(72·5%)。正常血糖组在PCI术前TIMI3级的患者多于高血糖症组(两组分别为27·3%和10·3%,P<0·01),但两组随诊期间主要心脏事件的发生率差异无统计学意义。结论高血糖症是STEMI患者PCI前冠状动脉TIMI血流重要的预测因素之一。     

Impaired myocardial perfusion and perfusion reserve associated with increased coronary resistance in persistent idiopathic atrial fibrillation.

AIMS: Patients with atrial fibrillation (AF) present with symptoms of myocardial ischaemia despite exclusion of coronary artery disease. A small vessel disease has been suggested. We quantified myocardial perfusion, perfusion reserve, and coronary vascular resistance (CVR) in AF patients using positron emission tomography (PET). METHODS AND RESULTS: Twenty-five male patients (age: 58 +/- 13 years) with persistent idiopathic AF were compared with 13 age- and risk-matched male controls (age: 56 +/- 8 years). Using H(2)(15)O-PET, myocardial blood flow (MBF) was quantified at rest, at hyperaemia (adenosine), and during cold-pressor-testing (CPT). Scans were repeated 4.1 +/- 2.3 months after cardioversion in 10 AF patients. In AF, resting MBF (0.95 +/- 0.19 vs. 1.14 +/- 0.22 mL/min/mL; P = 0.009), hyperaemic MBF (2.07 +/- 0.80 vs. 3.33 +/- 0.78 mL/min/mL; P < 0.001), and MBF under CPT (0.90 +/- 0.25 vs. 1.14 +/- 0.25 mL/min/mL; P < 0.014) were significantly reduced compared with matched controls. Hyperaemic CVR was increased in AF (47 +/- 21 vs. 29 +/- 7 mmHg x mL/min/mL; P = 0.012) but unchanged at rest and under CPT. After cardioversion, resting MBF and MBF under CPT in AF were similar to matched controls, however, hyperaemic MBF and CVR were not recovered. CONCLUSION: In AF, MBF at baseline, at hyperaemia, and at CPT is reduced, whereas CVR under hyperaemic conditions is increased. Following electrical cardioversion, these findings are partly reversible and therefore most likely secondary to the arrhythmia.     

临界性高血压患者冠状动脉血流储备功能的研究

目的 :了解无症状临界性高血压患者是否有冠状动脉功能异常。方法 :经食管超声心动描记术研究 2 0例正常人 (正常对照组 )及 17例无症状临界性高血压患者 (临界性高血压组 )的冠状动脉血流储备 (CFR)。以潘生丁静脉注射后和静息时舒张期的最大血流速度比率 (D/R PDV)和收缩期最大血流速度比率 (D/R PSV )作为CFR指标。结果 :1两组受检者静息时的 PDV无显著性差异〔(43± 10 ) m m/s∶ (46± 8) mm /s,P >0 .0 5〕;2静脉注射潘生丁后临界性高血压组的 D/R PDV、D/R PSV较正常对照组明显减少 ,两组之间有显著性差异 (D/RPDV:2 .2 5± 0 .36∶ 2 .86± 0 .42 ,D/R PSV:2 .0 0± 0 .2 6∶ 2 .5 6± 0 .41,P<0 .0 5 )。结论 :无症状临界性高血压患者 CFR能力降低。