存活心肌定量分析评价溶栓及PTCA急诊治疗AMI的效果

目的采用硝酸酯类药物介入心肌断层显像,用存活心肌定量分析结果评价溶栓和PTCA治疗AMI的效果.方法将35例AMI病人随机分成溶栓组和PTCA组,10天后做静态及异舒吉介入心肌断层显像,分别计算心肌缺损面积(%).治疗12周后行静态显像,并计算出缺损面积(%).结果溶栓组和PTCA组比较静态显像缺损面积(%)为32.04±17.95和29.88±15.43(P＞0.05),异舒吉介入显像缺损面积(%)为26.62±15.13和15.07±13.80(P＜0.05),存活心肌面积(%)为9.45士6.63和14.81±4.97(P＜0.05).术后12周缺损面积增加者溶栓组和PTCA组各为4例和7例.结论PTCA较溶栓治疗AMI可以得到更大面积的存活心肌,但术后12周PTCA组中病变面积又扩大的病人较溶栓组有增多趋势.     

含服硝酸甘油介入99mTc-MIBI心肌断层显像估测心肌存活性的价值

目的探讨舌下含服硝酸甘油(NTG)介入心肌血流灌注断层显像在评价心肌存活性中的价值.方法33例心肌梗塞患者进行了静息、NTG介入和经皮冠状动脉成形术(PTCA)后99mTc-MIBI心肌断层显像.以PTCA术后心肌断层显像结果为标准,对比分析NTG介入显像在心肌存活性评价中的准确性;并将所有患者按心电图有无病理性Q波分为两组,比较两组病例NTG介入显像时心肌灌注改善的差异.结果33例心肌梗塞患者共297个心肌节段中,静息心肌显像有121个节段(40.7%)灌注得到改善,而PTCA后显像中有68个心肌节段(56.2%)灌注改善,两者共有90个节段显像结果一致,总符合率为74.3%.无Q波组NTG介入显像改善率为56.6%,有Q波组仅为31.6%(＜0.01).结论含服硝甘油介入99mTc-MIBI心肌断层显像能较好的评价心肌心肌存活性,且方法简便,易于临床推广;无Q波心肌梗死患者可望在心肌血流重建治疗中有更多的频临死亡心肌得到存活.     

应用PET及SPECT评价干细胞心肌移植模型的稳定性和可靠性

目的:应用正电子发射断层摄影术(PET)、单光子放射计算机断层显像术(SPECT)评价干细胞心肌移植模型稳定性和可靠性。方法:12只杂种犬分两组,在全麻下左侧开胸建立前降支根部结扎和心尖区CO2冷冻慢性心肌梗死模型,分别于建立模型前、后4,8周应用18F-FDG心肌代谢PET(代谢显像)和99TCm-MIBI心肌SPECT(灌注显像)对两种模型进行评价,计数显像减低总节段数及心肌灌注与代谢的匹配关系,计算放射性分布缺损计数(F值)。结果:12只犬无1例死亡,正常心肌PET,SPECT显像清晰,F值接近零,结扎组术后8周心肌灌注F值(6.67±1.03),糖代谢F值(5.83±0.75)与术后4周(10.47±0.51,10.33±0.66)比较,均有不同程度的下降(P<0.05),冰冻组术后4,8周心肌灌注F值(5.67±0.82,5.17±0.98),糖代谢F值(5.50±1.31,5.00±1.55),差异无显著性意义(P>0.05)。在灌注减低区,结扎组术后4周梗死心肌占41.9%,8周占70%,冰冻组术后4周梗死心肌占91.7%,8周几乎占100%。结论:犬CO2冷冻慢性心肌梗死模型较结扎模型稳定,不受冠状动脉侧支循环的干扰,适宜进行犬慢性心肌梗死细胞移植的实验研究。     

硝酸甘油介入心肌断层显像在心肌存活评价的临床应用

目的：探讨硝酸甘油介入心肌断层显像在心肌存活评价的临床应用价值．方法：应用静息、硝酸甘油介入99m^TC-MIBI心肌血流灌注断层显像，对20例不稳定型心绞痛患(其中8例有陈旧性心梗病史)PTCA术前术后进行自身对比分析。结果：20例患160个心肌节段中、静息显像异常积分为196(1分33个节段、2分20个节段、3分41个节段)：硝酸甘油介入显像及PTCA术后静息显像异常积分均较术前静息显像明显减少且两积分接近，分别为104和97分。而核素分布正常节段分别增加46和53个心肌节段增加67.7％．77.9％．两相似(P>0.05)．两和术前静息显像相比有显差异(P<0.01)。术前患射血分数为44.5±12.6％，术后为56.4±16.3％，增加26.8%。结论：揭示桉素心肌硝酸甘油介入心肌断层显像对存活心肌评价简便无创，客观准确．为心绞痛患PTCA术前疗效提供了有力手段。     

经胸超声冠状动脉血流显像技术评价支架术前后冠状动脉血流储备的初步临床应用

目的　探讨经胸超声冠状动脉血流显像技术评估冠心病支架术前、后冠状动脉血流储备(CFR)的价值。方法　 2 8例冠状动脉前降支狭窄的冠心病患者对狭窄的冠状动脉行经皮冠状动脉内成形术 (PTCA)后各置入 1枚支架。分别于术前、术后 72h内 ,采用经胸超声多普勒冠状动脉血流显像技术检测左冠状动脉前降支狭窄远端静息舒张期血流峰速 (r Vd)、注射潘生丁时最大舒张期血流峰速 (d Vd)及CFR。结果　 2 8例患者行支架术均获成功 ,狭窄率由术前 84.2 %± 8.6%降至术后 5 .4%± 0 .8% ,(P <0 .0 5 ) 。 2 8例患者共 40支病变血管中 ,3 4支狭窄冠状动脉远端检测到多普勒频谱 (检出率 85 % )。支架术后r Vd较术前r Vd有增加趋势 ,但差异无显著性意义 ( P >0 .0 5 ) ;术后静脉注射潘生丁后最大d Vd及CFR均较术前明显增加 [( 0 .94± 0 .2 1)m/s对 ( 0 .5 1± 0 .18)m /s ,3 .2 1± 1.2 1对 1.89± 0 .40 ,均P <0 .0 5 ]。结论经胸超声多普勒冠状动脉血流显像技术结合潘生丁试验是一种简便、易行、无创性评价冠心病患者冠状动脉介入治疗前后血流储备变化的新方法。     

^99mTc—MIBI静息心肌显像观察PTCA支架术治疗不稳定性心绞痛的临床价值

目的比较PTCA+支架术前、后不稳定性心绞痛患者心肌缺血的程度.材料与方法50例不稳定性心绞痛患者均于术前及术后2周行99mTc-甲氧基丁基异(MIBI)静息心肌显像,将左室心肌分为20个节段,并对心肌摄99mTc-MIBI的程度进行打分,分别计算2次心肌显像的总积分(SWS)和两者相减的积分(SDS).结果PTCA+支架术后心肌显像的总积分S2WS(9.8±3.3)明显低于术前S1WS(15.2±3.4),SDS为5.6±2.5,改善程度为36.8%.结论用术前及术后的99mTc-甲氧基丁基异(MIBI)静息心肌显像比较可以较好的评价PTCA+支架术的疗效.     

腺苷负荷心肌核素显像在冠心病诊断与介入治疗中的作用

目的探讨腺苷负荷心肌核素显像在冠心病诊断及介入治疗中的作用。方法冠心病的可疑患者,行腺苷负荷心肌核素显像,部分患者进行冠脉造影和介入治疗,介入治疗前后进行腺苷负荷心肌核素显像检查对比。腺苷负荷心肌核素显像采用单光子发射断层显像图像采集系统,腺苷总量为840μg/kg静脉泵入,3 min后静脉推注99mTc-MBI925 MBq,90 min后进行心肌断层显像,如果发现心肌显像异常,次日再行静息心肌显像。结果134例冠心病患者,年龄21~85(63.3±14.8)岁,男90例,女44例,进行腺苷负荷心肌核素显像,109例提示有心肌缺血现象,25例正常,诊断阳性率达81.3%。12例患者经过冠状动脉造影,有冠脉狭窄的患者行PCI,前后复查腺苷心肌核素显像,介入后心肌核素血流灌注较介入前明显改善(P<0.01)。结论腺苷负荷心肌核素显像在冠心病的诊断中起着重要的作用,其敏感性与特异性较高,同时在冠心病介入治疗前后疗效评价方面有一定的临床意义。     

心肌灌注SPECT显像采用X线CT衰减校正的临床应用

目的：评价SPECT/CT复合成像装置采用CT X线对心肌灌注显像衰减校正的临床应用价值。方法：受检者65例，35例经临床病史、心电图、超声心动图等检查排除冠心病患者；30例临床诊断明确的冠心病患者。均行99mTc-甲氧基异丁基异晴（99mTc-MIBI）常规心肌断层显像及X线衰减校正显像，并与冠状动脉造影结果进行对比分析。结果：①非冠心病组和冠心病组下壁和后壁放射性摄取率由未采用X线CT衰减校正方法的（77.0±4.77）%和（76.0±5.7）%、（31±4.3）％和（35±5.5）％增至采用X线衰减校正方法的（85.0±4.5）%和（83.0±5.2）%、（38±5.1）％和（42±5.5）%，两组校正后均P＜0.001。②35例非冠心病患者经目测定性分析，衰减校正后，原下后壁放射性减低明显改善者82.8%，中度改善14.3%；30例冠心病患者经X线衰减校正后有改善者73.7%。③非冠心病35例和30例冠心病患者与冠状动脉造影结果对比，经X线衰减较正后心肌灌注显像符合率分别提高了8.6%和15.4%。结论：SPECT/CT复合显像装置对心肌灌注显像行X线衰减校正技术，方法简便，可以使大多数由于γ射线在组织中的衰减造成的放射性计数减低得到校正，尤其对左室下后壁的衰减校正更明显。经衰减校正后提高了心肌灌注图像质量，在临床诊断中减少了假阳性的发生，使诊断符合率提高。     

冠状动脉造影与99Tcm-MIBI心肌断层显像的对比分析

目的评价冠状动脉造影(CAG)与心肌灌注单光子发射计算机断层显像(SPECT)次极量99Tcm-甲氧基异丁基异腈(MIBI)运动心肌核素显像两项检查对冠心病的诊断价值.方法选择60例冠状动脉造影检查的患者,并在同期内(间隔＜8周)接受SPECT检查,将CAG结果与SPECT结果进行对比分析.结果60例患者中冠心病35例,其它心脏病14例中,高血压病11例,心肌核素4例为阳性(占36.4%),3例肥厚型心肌病1例为阳性(占33.3%),11例无器质性心脏病中2例心肌核素阳性(占18.2%).在冠心病的诊断中,冠状动脉造影的敏感性为97.1%,运动心肌核素的敏感性为91. 4%,特异性为81.8%.结论冠状动脉造影和核素心肌显像均为诊断冠心病的有效手段.由于后者的无创性,易于重复,是临床随访的较好方法.     

99m Tc-MIBI 心肌显像定量分析用于判定急性心梗溶栓术后存活心肌的价值

目的采用硝酸酯类药物介入心肌断层显像,研究急性心梗病人溶栓术后存活心肌的范围。方法将32例接受急性溶栓术的病人分成溶栓再通组(19例)和未再通组(13例),10天后行异舒吉介入的心肌断层显像,并分别计算出静态的及异舒吉介入的心肌缺损面积(%)和体积(%),得出存活心肌的面积(%)和体积(%)。结果溶栓再通组和未再通组比较静态显像缺损面积(%)为32.04±17.95和52.13±22.99(P<0.05),异舒吉介入显像缺损面积(%)为26.62±15.13和51.93±21.10(P<0.05),存活心肌面积(%)9.45±6.43和2.75±3.57(P<0.05)。静态显像缺损体积(%)为28.45±12.79和39.56±11.89(P<0.05),异舒吉介入显像缺损体积(%)为18.61±16.52和36.94±11.35(P<0.05),存活心肌体积(%)为9.84±2.39和2.62±1.45(P<0.05)。结论急性心肌梗塞溶栓再通是否成功与存活心肌的面积、体积有明显的关系,并且异舒吉介入心肌显像定量分析方法判断存活心肌的范围有一定临床价值。     

Fatty acid exercise scintigraphy after percutaneous transluminal coronary angioplasty

Summary . We performed a sequential fatty acid exercise-rest scintigraphy in 18 patients with an initially successful percutaneous transluminal coronary angioplasty (PTCA) to study the concordance of trends in symptoms, exercise tolerance and myocardial metabolism. Eleven patients stopped the exercise because of angina pectoris in the preoperative test; 2 days after PTCA this number decreased to two, but again increased to eight 3 months later. Exercise time (9–7 ± 0–6 min, mean ± SEM) and maximum exercise heart rate (128 ± 4 beats min^-1) were at least as good immediately after the operation as originally (8–8 ± 0–6 min and 121 ± 4 beats min^-1, respectively). After 3 months both parameters were significantly (P<0–05) better (10–3 ± 0–6 min and 136 ± 4 beats min^-1, respectively) than originally. Some relative improvement in washout was noticed in 61% 2 days and in 56% of cases 3 months after PTCA. Fatty acid exercise uptake was more homogeneous in 72% of cases immediately after angioplasty and in 44% 3 months later. The trend in fatty acid uptake, exercise characteristics, and also in symptoms was most favourable among the eight patients with a dilatated left anterior descending coronary artery. Although the gamma camera technique possibly underestimated the effects of angioplasty, the impaired fatty acid metabolism could be linked with persistent symptoms after the operation. We conclude that most patients can safely participate in a symptom-limited (maximal) ergometry test already 2 days after PTCA, and that postoperatively myocardial perfusion and metabolism improve rapidly. However, this advantage is eventually lost to some degree, even if exercise tolerance continues to improve.     

Variability of coronary flow reserve obtained immediately after coronary angioplasty

Coronary flow reserve (CFR) improves in most patients immediately following coronary angioplasty (PTCA). The degree of improvement, however, may be variable and its predictive value for a favorable long-term angiographic result is unknown. To evaluate these issues, we used digital subtraction angiography to measure CFR in 15 patients before and immediately after PTCA. Minimum coronary diameter improved and percent diameter stenosis was reduced immediately following PTCA (from 0.75 ± 0.35 mm to 2.19 ± 0.56 mm, and from 74 ± 12% to 27 ± 15%, respectively; p<0.001). While CFR improved in patients immediately following PTCA (from 1.49 ± 0.75 to 2.68 ± 1.73; p<0.05), a substantial variability in CFR measurements (range 0.80 to 8.33) was present. At repeat arteriography 2.9 ± 0.6 months later, 4 patients demonstrated restenosis. Compared with the 11 patients without restenosis, those with restenosis had similar coronary dimensions and CFRs immediately following PTCA. We conclude that coronary flow reserve, determined by digital subtraction angiography, improves in most patients immediately after PTCA but the degree of improvement is variable. Its ability to predict long-term angiographic outcome remains uncertain.     

多巴酚丁胺负荷多普勒组织超声心动图预测PTCA术后冬眠心肌功能改善的价值

目的：探讨PWDTI结合LDDSK预测PTCA术后冬眠心肌功能改善的价值。方法：采用PWDTI结合LDDSK测量36例陈旧性心梗患者(静息下观察82个室壁运动异常节段)PTCA术前1天静息下和负荷下室壁运动异常节段峰值收缩速度Vs，并计算负荷下S％增长。PTCA术后4～6周随访分析。结果：PTCA术后，46节段室壁运动改善，36节段室壁运动未改善。以S％＞35％为裁断值，PWDTI结合LDDSK预测PTCA术后室壁功能改善的敏感性86．9％、特异性86．1％、准确性86．6％、阳性预测值88．9％、阴性预测值83．8％。结论：脉冲多普勒组织成像结合多巴酚丁胺负荷超声心动图可识别冬眠心肌并准确地预测PTCA术后局部左室功能改善。     

经皮冠脉腔内球囊成形术对冠心病患者冠状循环中内皮素和其他血管活性物质的影响

10例冠心病患者于前降支腔内球囊成形术前、中、后5～10分钟和30～40分钟分别从升主动脉和冠状静脉窦取血测定内皮素(ET)、心钠素(ANP)和血管紧张素Ⅱ(ATⅡ)的水平.结果显示术中及术后早期冠状循环中血浆ET的水平无变化,至术后30～40分钟有轻度升高,但未达到统计学差异;术中ANP的水平明显升高(P<0.05)至30～40分钟降至术前水平;术中及术后ATⅡ的水平变化不明显.     

99mTc- MIBI心肌显像对心脏功能改善程度的评价

目的通过 99mTc- MIBI心肌显像评价 PTCA治疗后心脏功能改善的程度 . 方法对 31例病人分别在 PTCA治疗前后进行 99mTc- MIBI心肌显像 , 将左心室分成 9个节段 , 对 279个心肌节段进行治疗前后的对比分析 . 结果治疗后放射性分布稀疏的节段大部分接近正常 , 明显稀疏的节段有一半以上得到改善 , 放射性缺损节段无明显变化 . 结论 99mTc- MIBI心肌显像可预测血流灌注改善后存活心肌细胞恢复的可能性 , 客观地评估 PTCA治疗效果 .     

Dobutamine stress echocardiography early after myocardial infarction treated with thrombolysis

The aim of the study was to assess the ability of dobutamine stress echocardiography to detect myocardial viability and ischemia in patients with acute myocardial infarction treated with thrombolysis and to correlate the acute response to dobutamine with late spontaneous functional recovery at follow-up. Forty-two consecutive patients with myocardial infarction treated with thrombolysis underwent low- (5 and 10 mcg/kg/min) and high-dose (20 to 40 mcg/kg/min) dobutamine stress echocardiography at a mean of 7 ± 3 days of the acute phase. A follow-up 2D-echocardiogram was performed in all patients to evaluate the spontaneous recovery of function in the infarct area. On the basis of the response to the test, 3 groups of patients were identified: group 1 included 7 patients showing an improvement in left ventricular asynergy score index at low doses (from 1.5±0.3 to 1.3±0.2, p<0.05) with no deterioration at high doses, indicative of myocardial viability without ischemia; group 2 (23 patients) showed a significant improvement in the asynergy index at low doses (from 1.58±0.3 to 1.32±0.32, p<0.05) followed by a deterioration at high doses (1.68±0.4, p<0.05 vs low-dose), suggestive of residual myocardial ischemia in the infarct zone; group 3 included 12 patients who showed no significant changes in the baseline asynergy score index (1.67±0.2) either at low or at high doses. The acute response to dobutamine stress echocardiography accurately predicted the spontaneous recovery of function in the infarct area at follow-up: both group 1 and group 2 patients showed a significant reduction in the asynergy score index (group 1: 1.16±0.3 vs 1.5±0.2, p<0.001; group 2: 1.43±0.3 vs 1.58±0.3, p<0.05), while group 3 had no recovery in the asynergy index (1.67±0.2 vs 1.67±0.2). Thus, in patients with acute myocardial infarction treated with thrombolysis dobutamine stress echocardiography can detect myocardial viability in 71% and ischemia in the infarct zone in 55% of patients; moreover, the response to the test during the acute phase is correlated with the degree of the late spontaneous recovery of function in the infarct area.     

Caffeine intake inverts the effect of adenosine on myocardial perfusion during stress as measured by T1 mapping

Caffeine intake before adenosine stress myocardial perfusion imaging may cause false negative findings. We hypothesized that the antagonistic effect of caffeine can be measured by T1 relaxation times in rest and adenosine stress cardiac magnetic resonance imaging (CMR), as T1 mapping techniques are sensitive to changes in myocardial blood volume. We prospectively analyzed 105 consecutive patients with adenosine stress perfusion CMR on a 1.5-T MRI system. Rest and stress T1 mapping was performed using Modified Look-Locker Inversion recovery. T1 reactivity was defined as difference in T1_rest and T1_stress (?T1). Fifteen patients drank coffee within 4 h of CMR (<4H caffeine group), and 10 patients had coffee the day before (>8H caffeine group). Comparison was made to patients without self-reported coffee intake: 50 with normal CMR (control group), 18 with myocardial ischemia, and 12 with myocardial infarction. The national review board approved the study; all patients gave written informed consent. The <4H caffeine group showed inverted ?T1 of ?7.8?% (T1_rest 975?±?42 ms, T1_stress 898?±?51 ms, p?<?0.0005). The >8H caffeine group showed reduced T1 reactivity (1.8?%; T1_rest 979 ms, T1_stress 997 ms) compared to the controls (4.3?%; T1_rest 977?±?40 ms, T1_stress 1018?±?40 ms), p?<?0.0005. Ischemic and infarcted myocardium showed minimal T1 reactivity (0.2 and 0.3?%, respectively). Caffeine intake inverts the adenosine effect during stress perfusion CMR as measured by T1 mapping. T1 reactivity can assess the adequacy of adenosine-induced stress in perfusion CMR.     

Improvement of coronary morphology and blood flow after stenting

Intravascular ultrasound (IVUS) and intracoronary Doppler (ICD) were performed in eight patients (54.3±6.5 years, 6 male) immediately after PTCA and after stenting. ICD was also performed before PTCA. After PTCA, IVUS has demonstrated intimal rupture in all patients. After stenting, IVUS revealed wall wrapping of the intimal flap with a free lumen in all patients. The lumen diameter was 2.42±0.55 mm after PTCA and was 2.74±0.49 mm after stenting (p<0.001). The cross-sectional area increased from 4.70±1.99 mm² post-PTCA to 6.40±2.15 mm² post-stent (p<0.005). Coronary flow velocity reserve, calculated by the ratio of mean flow velocity at rest and after intracoronary papaverine administration, increased from 2.05±1.01 to 2.99±1.14 after PTCA (p = 0.015); and increased to 4.51±1.33 after stenting (p<0.001). The morphological data derived from IVUS correlated with the functional information obtained with ICD. In addition to its established role in bail out situations, stent implantation may be considered when a suboptimal morphological and functional result has been demonstrated.     

纤维蛋白溶解系统功能与冠状动脉腔内成形术后再狭窄的关系

目的 :探讨纤维蛋白溶解 (纤溶 )系统成分在冠状动脉腔内成形术 (PTCA)后再狭窄过程中的作用 ,明确纤溶功能与再狭窄的关系。方法 :因单支血管病变或多支血管病变仅有单支血管行择期 PTCA的 2 8例患者 ,男 2 3例 ,女 5例 ,平均年龄 (5 5 .8± 9.5 )岁 ,于手术后平均 (6 .4± 2 .4)个月进行冠状动脉 (冠脉 )造影随访。分别测定患者 PTCA术前 ,术后 1周 ,术后 3个月及冠脉造影随访前血浆中组织型纤溶酶原激活剂 (t PA) ,纤溶酶原激活剂抑制物 (PAI 1)和纤维蛋白原 (Fg)的水平。结果 :再狭窄组术后 1周、3个月的 t PA活性分别为 (1.86± 0 .5 8) k U/ L、(1.91± 0 .44 ) k U/ L,较术前 (2 .83± 0 .72 ) k U/ L 明显降低 (P均 <0 .0 5 ) ;再狭窄组术后 1周、3个月的 PAI 1活性分别为 (12 .37± 2 .33) k AU/ L、(12 .36± 2 .2 9) k AU/ L,较术前 (9.13±2 .14) k AU/ L显著升高 (P均 <0 .0 0 5 ) ,而且明显高于非再狭窄组〔分别为 (8.35± 2 .10 ) k AU/ L、(8.39±2 .74) k AU/ L,P均 <0 .0 5〕;术前、术后 Fg无明显差异。结论 :PTCA术后 1周～ 3个月纤溶功能受损影响血管损伤的修复 ,与再狭窄密切相关 ,连续监测纤溶成分可能有助于预测再狭窄发生