核素心肌显像在冠状动脉旁路移植术中的应用

心肌存活的判断对于严重冠心病患者选择再血管化适应证、估测疗效和判断预后有着极其重要的临床意义。传统的^201T1静息-再分布显像能较好又经济地评估心肌活力，门控显像技术显示的室壁运动情况能帮助医师更准确地判断缺血心肌的活力，^18F-氟代脱氧葡萄糖（^18F-FDG）心肌代谢显像是迄今评估心肌活力最准确的方法。患者在冠状动脉旁路移植术后出现胸闷症状时，核素心肌显像也能准确地判断有无新发缺血灶或是原有病变术后再狭窄。     

CCTA评价冠状动脉狭窄程度与SPECT心肌灌注显像关系的研究

目的：探讨冠心病患者CCTA不同狭窄程度与SPECT MPI间的关系。方法68例患者进行了CCTA和MPI检查,所有患者均行冠状动脉造影。CCTA按管腔狭窄程度分为5个级别,即0,1%~24%,25%~49%,50%~74%,75%~100%。MPI分为正常和灌注缺损(包括可逆缺损和不可逆缺损)。结果68例患者共204根血管纳入分析。以患者为单位进行分析,40例CCTA显示管腔重度狭窄的患者中,29例(72.5%)MPI显示灌注缺损。另外11例(27.5%)CCTA异常的患者心肌灌注 MPI显示正常。在28例CCTA显示未见明显狭窄的患者中,17例(60.1%)显示心肌灌注正常,而另外11例(39.9%)显示灌注缺损。根据CCTA冠状动脉狭窄程度分组,心肌灌注缺损(包括不可逆性灌注缺损和可逆性灌注缺损)出现的比率：0,1%~24%,25%~49%,50%~74%,75%~100%分别为5(27.7%)/18,1(33.3%)/3,5(71.5%)/7,4(50%)/8,25(78.1%)/32。结论冠状动脉狭窄和灌注缺损的不匹配多发生在冠状动脉中度狭窄的患者。在轻度狭窄和重度狭窄的患者中,二者多匹配。冠状动脉中度狭窄的患者应进行CCTA和 MPI联合检查评价冠心病。     

Noninvasive perfusion control by thallium-201 myocardial scintigraphy after coronary artery bypass surgery

Thallium-201 myocardial scintigraphy, which has been shown accurate in the assessment of myocardial perfusion, was employed in the evaluation of 34 patients after coronary artery bypass surgery. In 28 patients (82.4%), there was a clear correspondence in the postoperative studies between the defects shown on scintigraphy and the coronary artery stenosis documented by arteriography. Thallium imaging after coronary artery bypass revealed an increased or newly developed scintigraphic defect in eight of 10 patients with recurrent angina. Follow-up arteriography in these 10 patients revealed occlusion or stenosis of the bypass graft in five, perioperative myocardial infarction in two, and increased stenosis of a preoperatively less occluded artery in two. In 24 patients with postoperative clinical improvement or relief of angina,²⁰¹Tl scintigraphy revealed complete normalization of thallium uptake in three, improvement of uptake in 17, and unchanged uptake defects in four. Presented at the 5. Herbsttagung der Deutschen Gesellschaft für Kreislaufforschung, October 28, 1978, Berlin.     

SPECT myocardial perfusion imaging with prone-only acquisitions: correlation with coronary angiography

Background  Recent evidence suggests that combining supine and prone acquisitions during stress-gated SPECT myocardial perfusion imaging (MPS) improves detection of obstructive coronary artery disease (CAD), though the additional imaging time required may not be feasible in routine clinical practice. MPS with prone-only acquisitions is occasionally performed in many laboratories, though little is known about the ability of modern MPS with prone-only acquisitions to detect obstructive CAD. Our goal was to assess the ability of MPS with prone-only acquisitions to detect obstructive CAD as determined by coronary angiography. Methods and Results  We studied 386 patients referred for MPS with either recent coronary angiography or a low pretest likelihood of coronary artery disease. All rest and stress images were obtained exclusively in the prone position. The sensitivity of prone-only MPS was 88% for detecting ≥50% coronary artery stenosis and 92% for detecting ≥70% coronary artery stenosis as determined by coronary angiography. Normalcy rate for prone-only MPS in patients with low probability for CAD was 95%, and normalcy rates did not significantly differ among coronary artery distributions. Conclusions  The findings of this study suggest that MPS using prone-only acquisitions is a reasonable diagnostic option for the detection of ischemia due to obstructive coronary artery disease.     

Myocardial perfusion imaging evidence of functionally complete revascularization by minimally invasive direct coronary artery bypass in 2-vessel coronary artery disease

Background Whether patency of a second diseased vessel still impacts myocardial perfusion when complete revascularization of the left anterior descending coronary artery (LAD) territory has been achieved is currently undetermined. In patients with 2-vessel coronary artery disease and complex LAD lesions, we evaluated the impact of single LAD or integrated revascularization on single photon emission computed tomography-assessed reversible myocardial ischemia. Methods and Results Thirty-five candidates for revascularization with double-vessel disease including the LAD and a preoperative stress single photon emission computed tomography study were studied. Revascularization was performed by minimally invasive direct coronary artery bypass (MIDCAB) alone (n=15) or by an integrated procedure with second-vessel angioplasty, either soon after surgery (n=13) or at 2 months (n=7), according to the extent of reversible perfusion defects in the second vessel territory. At 1 year, the total ischemic area decreased from 9.3±5.1 to 0.8±1.5 in MIDCAB-only patients and from 8.2±4.9 to 1.6±2.9 in the integrated group (P=.87 for treatment and P<.001 for time). The ischemic area in the second vessel territory similarly decreased in both groups (P=.81 for treatment and P<.001 for time). Conclusions In 2-vessel coronary artery disease involving the LAD, MIDCAB alone achieves, in a substantial proportion of patients, functionally complete revascularization even in the nonrevascularized second vessel territory. The study was supported by grant ICS030.6 RF99/15 from the Italian National Ministry of Health.     

Comparison of dobutamine stress echocardiography, dobutamine SPECT, and adenosine SPECT myocardial perfusion imaging in patients with end-stage renal disease

Objectives  We sought to assess and compare the diagnostic accuracy and prognostic value of dobutamine stress echocardiography (DSE), dobutamine SPECT, and adenosine SPECT myocardial perfusion imaging (MPI) in patients with end-stage renal disease (ESRD). Background  The optimal stress imaging modality for patients with ESRD has not yet been determined. Methods  Forty-nine patients with ESRD underwent DSE, dobutamine SPECT MPI, and adenosine SPECT MPI. The primary endpoint of the trial was concordance between stress tests with respect to the presence or absence of ischemia. Results  Agreement on the presence or absence of ischemia between adenosine SPECT MPI and DSE was 69% (kappa = .25, P = NS). Agreement on the presence or absence of ischemia between adenosine and dobutamine SPECT MPI was 77% (kappa = .37, P = <.009). Summed stress scores for adenosine and dobutamine SPECT MPI studies were highly correlated (r = .9, P = <.0001). DSE and SPECT MPI results provided incremental prognostic information when added to clinical variables. Conclusions  There is moderate concordance between DSE and adenosine SPECT MPI in ESRD patients referred for stress testing. Interobserver agreement was higher for SPECT MPI compared to DSE. Based on these observations, the optimal approach for diagnosing severe coronary artery disease and assessing risk in patients with ESRD has yet to be determined, but appears to warrant further investigation. Supported by grants from Hennepin Faculty Associates, the Minneapolis Medical Research Foundation, and DuPont Pharmaceuticals.     

Dobutamine Tc-99m furifosmin SPECT in detection of coronary artery disease: Evaluation of same day,rest-stress protocol

The purpose of this study was to evaluate the feasibility and diagnostic accuracy of same day rest-stress myocardial perfusion SPECT (MP SPECT) protocol by using technetium-99m (Tc-99m) furifosmin in conjunction with dobutamine stress test in subjects in whom coronary artery disease (CAD) had been proven or excluded at coronary angiography (CA). The study group consisted of 25 patients (8 female and 17 male with a mean age of 53.04±8.56 yrs) unable to perform treadmill exercise or unsuitable for pharmacologic vasodilator stress testing. Ten mCi (370 MBq) of Tc-99m furifosmin was injected intravenously at rest. Sixty min after injection, planar and SPECT images were acquired. One hour later all patients underwent dobutamine stress test. At the peak stress, 20 mCi (740 MBq) of Tc-99m furifosmin was injected. Sixty min after stress dose injection, planar and SPECT images were acquired. Rest-stress planar and SPECT data were evaluated by using visual and quantitative analysis. Heart to adjacent organ (Heart/Lung; H/Lu and Heart/Liver; H/Li) activity ratios were calculated from anterior planar images by using regions of interest (ROI). SPECT data were interpreted by using 20 segment-5 point scoring system from short axis and vertical long axis slices. The results of rest-dobutamine stress Tc-99m furifosmin MP SPECT were compared with CA results. There were statistically significant differences between H/Lu and H/Li ratios at rest and stress conditions. Heart/adjacent organ activity ratios were similar and significant statistical difference could not be found between CA positive and CA normal patients. Sensitivity, specificity and accuracy for Tc-99m furifosmin SPECT study were calculated as 90%, 80% and 84% for left anterior descending (LAD), 87%, 94% and 92% for left circumflex (LCx) and 67%, 86% and 80% for right coronary artery (RCA), respectively. Overall sensitivity, specificity and accuracy were calculated as 83%, 87% and 85%, respectively. According to the results obtained in this study, it may be concluded that same day rest-dobutamine stress Tc-99m furifosmin SPECT protocol is a feasible and accurate technique in the evaluation of CAD, especially in patients unable to perform treadmill exercise or unsuitable for pharmacologic vasodilator stress testing.     

Clinical utility of coronary calcium scoring after nonischemic myocardial perfusion imaging

BACKGROUND: Coronary artery calcium (CAC) scoring is increasingly being used after myocardial perfusion imaging (MPI) to detect preclinical coronary artery disease (CAD). However, there are few data to support this approach. METHODS AND RESULTS: We reviewed 200 consecutive patients without known CAD who were referred for CAC scoring shortly after nonischemic MPI. Of these, 13 (6.5%) had CAC scores greater than 400, indicating significant CAD; 22 (11%) had CAC scores of 101 to 400; 27 had CAC scores of 11 to 100; and the remainder (n = 138) has CAC scores of 1 to 10. Traditional risk factors and patient characteristics were not significant predictors of CAC scores of 101 or greater. However, age and the Framingham risk score were predictors of CAC scores greater than 0. At follow-up, significantly more patients with CAC scores of 101 or greater had been given the advice to take lipid-lowering medication and aspirin compared with those with CAC scores of 0. CONCLUSIONS: Of patients referred for CAC scoring after nonischemic MPI, 17.5% were identified as having CAD based on a CAC score greater than 100, allowing intervention with aggressive medical therapy. Patients who were reclassified were not easily identifiable by traditional risk factors, but Framingham risk score did predict the presence of CAC. Clinicians modified medical therapy based on the results of CAC scoring.     

慢性稳定型冠心病的核素心肌灌注显像临床应用进展

多项临床试验证明,核素心肌灌注显像在冠心病诊断、危险度分层、预后判断、病人处理方案等方面具有突出的作用和优越的价值。在ACC/AHA(美国心脏病学院/美国心脏学会)有关冠心病和核心脏病学指南中,心肌灌注显像的上述作用得到了充分肯定。合理应用该项技术可以提高对冠心病诊断、处理的整体水平,并使有限的医疗资源得到更合理利用,这在我国目前显得十分迫切和需要。     

Assessment of perfusion, function, and myocardial metabolism after infarction with a combination of low-dose dobutamine tetrofosmin gated SPECT perfusion scintigraphy and BMIPP SPECT imaging

BACKGROUND: Tetrofosmin gated single photon emission computed tomography (SPECT) allows simultaneous assessment of regional myocardial perfusion, global and regional left ventricular function, and function at rest and during pharmacologic intervention. SPECT with fatty acid analogues, such as beta-methyl-iodophenyl-pentadecanoic acid (BMIPP), can be used to monitor metabolic changes induced by myocardial ischemia. In this work, the results of both studies obtained in patients with recent myocardial infarction are integrated. METHODS: Twenty patients underwent tetrofosmin and BMIPP scintigraphy with a 3-head camera. Two consecutive tetrofosmin gated SPECT acquisitions were performed 60 minutes after administration of technetium-99m tetrofosmin (925 MBq) at rest (3x20 stops of 9 s; matrix 64x64 over 360 degrees . One acquisition was made at rest, and the second was made during dobutamine infusion (10 microg/kg/min). Regional functional abnormalities were quantified and expressed as wall thickening severity (WTsev) in arbitrary units. Left ventricular ejection fraction and volumes were assessed with the Cedars Sinai algorithm. BMIPP imaging started 20 minutes after iodine 123-BMIPP (150 MBq) administration at rest (3x32 stops of 60 s; matrix 64x64 over 360 degrees; medium energy collimators). Tracer uptake was scored according to a 25-segment model. RESULTS: Sixteen of 18 patients had regional functional abnormalities at baseline (average WTsev 13.7 units). The WTsev score at baseline correlated well with the degree of residual perfusion. During dobutamine infusion, WTsev did not change (from 23.4 to 23.6 units) in 5 patients; it decreased (from 16.1 to 5.9 units) in 11 patients; and it increased (from 13.0 to 22.3 units) in 3 patients. An increase or decrease in WTsev during dobutamine infusion was associated with the presence of a considerable amount of BMIPP mismatched myocardium, whereas no change in WTsev was preferentially associated with a BMIPP matched pattern and perfusion defects with a higher severity score. CONCLUSION: Immediately after infarction, the severity of regional dysfunction at rest correlated well with the perfusion defect severity. Improvement in regional function during dobutamine administration is associated with less severe perfusion defects and a considerable amount of BMIPP mismatched myocardium, both suggesting viability.     

Prospective multicenter evaluation of rapid, gated SPECT myocardial perfusion upright imaging

Background  A novel three-dimensional (3D) iterative image reconstruction method (3D-OSEM) has been developed that in phantom studies yielded comparable image quality at one half the imaging time. In this study, we compared standard (STD) and rapid (nSPEED) protocols for diagnostic quality of images and quantitation of end-diastolic volume (EDV), end-systolic volume (ESV), left ventricular ejection fraction (LVEF), and perfusion defect severity. Methods  At 11 US community centers, 448 patients prospectively underwent rest–stress-gated SPECT imaging using Tc-99m-labeled agent. The difference in quality and diagnostic equivalence of STD and nSPEED images were blindly evaluated by three experts. Defect intensity was quantitated as %normal in the three coronary artery territories. Results  Studies were abnormal in 40% of patients. In 98.7% of stress and 98% of rest images, the nSPEED image quality was identical to or better than the STD images. nSPEED images were diagnostically equivalent to the STD in 444/448 (99%) patients. A high correlation was observed between nSPEED and STD studies for measurement of EDV (Y = 0.957X, R ² = 0.99), ESV (Y = 0.962X, R ² = 0.99), and LVEF (Y = 1.005X, R ² = 0.96). STD and nSPEED studies were not significantly different (P = ns) for quantitative perfusion defect severity. Conclusion  Rapid, gated rest–stress myocardial perfusion upright SPECT imaging may be achieved without compromising perfusion and function information. Financial support for this study was partly provided by Digirad Corporation, Poway, CA.     

核素心肌显像在冠状动脉旁路移植术中的应用

心肌存活的判断对于严重冠心病患者选择再血管化适应证、估测疗效和判断预后有着极其重要的临床意义。传统的201Tl静息-再分布显像能较好又经济地评估心肌活力,门控显像技术显示的室壁运动情况能帮助医师更准确地判断缺血心肌的活力,18F-氟代脱氧葡萄糖(18F-FDG)心肌代谢显像是迄今评估心肌活力最准确的方法。患者在冠状动脉旁路移植术后出现胸闷症状时,核素心肌显像也能准确地判断有无新发缺血灶或是原有病变术后再狭窄。     

核素心肌显像在冠心病处理决策中的合理应用及其原理

核素心肌显像在冠心病诊断、危险度分层及预后判断方面积累了大量资料,并可据此制定冠心病的有效处理策略。在ACC/AHA(美国心脏病学会/美国心脏协会)有关冠心病和核心脏病学指南中,核素心肌显像的上述作用得到了充分肯定。合理应用该技术可以提高我们对冠心病诊断处理的整体水平,并使有限的医疗资源得到更合理利用,目前这在我国显得十分迫切和必要。     

Diagnostic value of MDCT angiography in assessment of coronary artery bypass graft

Purpose

To evaluate the diagnostic value of MDCT angiography in assessment of coronary bypass grafts. We studied 51 patients from April 2008 to October 2011. All patients gave written informed consent, and the study protocol was approved by the Institutional Review Board. 96 grafts including 35 left internal mammary artery (LIMA) grafts, 5 radial artery grafts, and 56 saphenous vein grafts (SVG) were assessed by 64-MDCT and the results were compared with conventional coronary angiography as reference standard.

Results

The diagnostic value of multi-detector computed tomography for graft occlusion was: 100% sensitivity, 100% specificity, 100% positive predictive value, and 100% negative predictive value. The diagnostic power of multi-detector computed tomography for stenosis of the graft anastomosis was: 100% sensitivity, 96% specificity, 87.5% positive predictive value, and 100% negative predictive value, and 96.4% accuracy.

Conclusion

Multi-detector computed tomography has become an alternative to coronary angiography to diagnose graft occlusion and stenosis after coronary artery bypass. In addition, multidetector CT has the added advantage over traditional angiographic evaluation of simultaneously allowing evaluation for alternate postoperative complications that may also manifest with chest pain and dyspnea, thereby mimicking recurrent angina.     

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。     

N末端脑钠肽前体对冠脉搭桥术后情况预测作用

目的探讨N末端脑钠肽前体(NT-pro BNP)水平对冠脉搭桥术术后并发症的预测作用及其预测精确程度。方法选择哈尔滨医科大学附属第四医院自2012年6月至2013年3月行冠脉搭桥术的40例患者为研究对象。于手术当天诱导麻醉前,测量40例行孤立冠脉搭桥术患者的术前血浆NT-pro BNP水平,探讨其与冠脉搭桥术后早期死亡(出院前或出院后30 d内)、引流过多(引流量>850 ml)、输血(新鲜冰冻血浆、浓缩红细胞悬液、冷沉淀凝血因子、去白细胞血小板等)、呼吸衰竭、机械通气时间延长(通气时间>12 h)、心房颤动、心衰综合征、使用主动脉内球囊反搏或者变力性药物支持血流动力学改变、谵妄、急性肾衰或内脏缺血发生情况的相关性。结果纳入研究的冠心病患者术前平均NT-pro BNP血浆水平为380.6 ng/L(92~3 496 ng/L)。心肺转流平均时间157 min(82~213 min),主动脉夹闭平均时间106 min(53~160 min)。术前NT-pro BNP血浆水平可精确诊断(ROC曲线下面积>0.8)机械通气时间延长、呼吸功能衰竭、变力性药物(肾上腺素)应用;NT-pro BNP中度诊断敏感(ROC曲线下面积0.7~0.8)为变力性药物(多巴胺)应用;NT-pro BNP较弱诊断敏感(ROC曲线下面积0.6~0.7)术后引流过多、血小板输入、心房颤动、心衰综合征。结论行孤立冠状动脉旁路移植术的冠心病患者术前血浆NT-pro BNP浓度是预测冠脉搭桥术术后情况的一项有价值的诊断方式。NT-pro BNP术前预测价值尤其适用于机械通气时间延长、呼吸功能衰竭、变力性药物(多巴胺,肾上腺素)应用。     

非体外循环心脏跳动下冠状动脉旁路移植术582例

目的总结582例非体外循环辅助下冠状动脉旁路移植术(OPCAB)的手术技巧及术后处理的临床经验,并对其疗效及治疗经验进行初步探讨。方法回顾1998年10月~2005年4月共完成OPCAB582例,男506例,女76例,年龄35~86岁,其中不稳定型心绞痛558例,术前合并其他疾病480例。结果搭桥为2·6±1·3支/例,搭桥术后辅助呼吸时间为3·2±1·2h,术后住院为7±1·6天,心绞痛症状均消失。死亡2例,再次开胸止血1例,其余患者术后无纵隔感染和出血等并发症,均痊愈出院。近、中期随访临床效果满意。结论OPCAB由于避免了体外循环,减少了手术创伤和全身炎症反应,缩短了术后恢复时间,术后早期并发症发生率和死亡率低,对高危患者具明显优势。     

老年患者冠状动脉旁路移植术围术期处理策略

目的总结65岁以上老年患者行冠状动脉旁路移植术(CABG)的结果,研究围术期处理策略。方法对65岁以上患者行CABG术394例进行总结,其中357例(90·6%)为不稳定型心绞痛,364例(92·4%)合并其他疾病;246例(62·4%)采用非体外循环心脏不停跳下CABG(OPCAB),148例(37·6%)选择常规体外循环下CABG(CCABG)。胸膜外技术游离左乳内动脉(LIMA),保持胸膜腔完整,常规将LIMA与左前降支吻合,其余桥用大隐静脉。术中使用即时超声血流仪测量移植血管血流,保证吻合口通畅。术后加强物理治疗和营养支持,严格控制血糖于6~10mmol/L。结果移植血管数行CCABG患者为3·1±0·6支,行OPCAB患者为2·4±0·8支;379例(96·2%)使用LIMA。全组死亡3例(0·76%),发生并发症9例(2·28%)。术后呼吸机使用时间OPCAB患者为9·7±5·4h,CCABG患者为20·3±15·0h。术后住ICU时间2·7±1·0天,住院时间11·8±5·0天。结论术前充分评估手术风险,选择恰当的手术方案,围术期进行精细处理,老年患者亦可取得良好手术效果。