I-MIBG myocardial scintigraphy as a noninvasive screen for the diagnosis of coronary artery spasm

Background. It has been suggested that the sympathetic nervous system might play an important role in the development of coronary artery spasm. However, no cardiac imaging modality has been able to demonstrate abnormal sympathetic innervation in patients with coronary artery spasm. The purpose of this study was to assess the presence and location of abnormal sympathetic innervation using iodine 123-metaiodobenzylguanidine (¹²³I-MIBG) single photon emission computed tomography (SPECT) and to evaluate the clinical efficacy of ¹²³I-MIBG SPECT as a noninvasive screening test in patients with coronary artery spasm.Methods and Results. Coronary arteriography and a provocative test with intravenous administration of ergonovine maleate were performed in 26 patients (20 men, 6 women, mean age 48.2 ± 12.0 years, range 20 to 67 years) who were suspected of having a coronary artery spasm. The subjects were divided into 2 groups: group 1 (n = 18) comprised subjects with a positive provocative test result, and group 2 (n = 8) comprised subjects with negative provocative test results. Ten healthy subjects served as controls. No abnormal MIBG uptake was observed in the control subjects. Abnormal sympathetic nervous innervation using ¹²³I-MIBG SPECT was observed either as a reduced uptake or a defective pattern in the perfused areas in 13 of the 18 regions supplied by vessels of ergonovine-induced vasospasm. Normal sympathetic innervation, as evidenced by normal ¹²³I-MIBG uptake, was noted in all of the 60 segments of normal vessel territories. Reduced uptake of ¹²³I-MIBG was not detected in the perfused areas of 5 vasospasm-induced vessels (perfusion territory of left anterior descending coronary artery [LAD] and the right coronary artery [RCA] in 2 and 3 patients, respectively). The sensitivity and specificity of ¹²³I-MIBG for detection of coronary artery spasm were 72.2% (95% confidence interval [CI] 55 % to 89 %) and 100 %, respectively. The positive predictive and negative predictive values were 100% and 92.3% (95% CI 91% to 93%), respectively.Conclusion. ¹²³I-MIBG SPECT is a feasible method to evaluate noninvasively and localize the territories of coronary arteries with spasm. Invasive diagnostic coronary arteriography with ergonovine provocation test may be unnecessary for diagnosis of coronary artery spasm in patients with typical resting pain, negative exercise test or normal thallium perfusion scan results, but showing abnormalities in ¹²³I-MIBG SPECT.     

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.     

Serial change in123I-MIBG myocardial scintigraphy in non-insulin-dependent diabetes mellitus

PURPOSE: We performed 123I-MIBG (MIBG) myocardial scintigraphy twice in patients with non-insulin-dependent diabetes mellitus (NIDDM) to investigate whether MIBG distribution was improved by pertinent clinical control. To determine the influential factors for MIBG distribution, we investigated the association between various clinical parameters and the serial change in MIBG uptake parameters. PATIENTS AND METHODS: Twenty NIDDM patients with no cardiac disorders were evaluated. Planar images were taken at 30 minutes (early) and 3 hours (delayed) after MIBG injection. The heart-to-upper-mediastinum uptake ratio (H/M) and washout ratio (WR) were calculated as parameters for estimating cardiac sympathetic function. Patients were divided into two groups, eight in the improved group and twelve in the unimproved group, according to the serial change in H/M. The mean interval between the baseline and the follow up study was 2.1 +/- 0.6 year. Differences between the means of the laboratory data in patients in both groups were compared for the baseline and the follow up study by using the paired t-test. As a means of determining the influential factors for a serial change of MIBG uptake, Fisher's exact test was performed to evaluate the association between the serial change in cardiac MIBG parameters and changes in other clinical parameters, such as blood sugar (BS) control, BS control method (insulin therapy), serum cholesterol control, and severity of diabetic complications. We also analyzed the association between the changes in CV(R-R) (coefficient variance of R-R intervals at rest ECG) or NCV (velocity of posterior tibial nerve) and those of other clinical parameters. Associations among these neurological parameters (MIBG parameters, CV(R-R) and NCV) were also analyzed. RESULTS: Paired t-tests showed a significant decrease in fasting blood sugar and fructosamine in the improved group in the follow up study compared to those in the baseline study. Nevertheless, Fisher's exact test showed no significant association between FBS, HbA1C, fructosamine and the improvement in cardiac MIBG uptake. The only significant association was observed between the serial change in H/M and the BS-control method (insulin therapy). Within the neurological parameters, a significant association was noted between the serial changes in H/M and CV(R-R). CONCLUSION: Although BS control was likely to be an important factor, it did not always ameliorate cardiac MIBG uptake. Based on the significant association between the BS-control method (insulin therapy) and MIBG uptake change, the severity of diabetes mellitus was likely to be a more influential factor. It was suggested that cardiac MIBG uptake could improve within the mild stage if controlled by diet therapy or an oral hypoglycemic agent in NIDDM.     

Sixty-four-slice computed tomography coronary angiography compared with myocardial perfusion scintigraphy for the diagnosis of functionally significant coronary stenoses in patients with a low to intermediate likelihood of coronary artery disease

Background. Multislice computed tomography coronary angiography (CTA) was proposed as a method for investigating possible coronary artery disease (CAD) in patients who present with chest pain but with a low to intermediate likelihood of CAD. Sixty-four-channel CTA was compared prospectively with ^99mTc-tetrofosmin myocardial perfusion scintigraphy (MPS) (as the gold standard in the detection of flow-limiting stenoses) for the detection of functionally significant CAD. Methods and Results. Fifty-two consecutive symptomatic patients with a low to intermediate likelihood of coronary artery disease, and who were referred for MPS, also underwent CTA. The CTA datasets were analyzed by two experienced observers who were blinded to the MPS data, and coronary artery segments were reported as <50%, 50% to 69%, 70% to 99% stenoses, or occluded. The MPS images were similarly analyzed for inducible perfusion abnormalities, and coronary territories were identified. At the patient level, agreement between CTA and MPS for CTA lesions at ≥50% was 87% (sensitivity, 100%; specificity, 84%; positive predictive value, 50%; negative predictive value, 100%). For CTA lesions, agreement at ≥70% was 96% (sensitivity, 86%; specificity, 98%; positive predictive value, 86%; negative predictive value, 98%). Conclusions. In patients with a low to intermediate likelihood of CAD, there is good correlation between MPS and CTA for the detection of functionally significant coronary artery stenoses when CTA detects a narrowing of ≥70% severity. Computed tomography coronary angiography stenoses of 70% should be used to determine functional significance, and not 50%, as is the usual practice at present. This work was funded by an unrestricted research grant from the United Kingdom Defence Postgraduate Medical Deanery. We also thank the Royal Air Force Medical Branch for financial support.     

Myocardial scintigraphy with I-123 heptadecanoic acid as a test for coronary heart disease

We have evaluated ¹²³I-heptadecanoic acid for myocardial scintigraphy in the diagnosis of coronary heart disease by comparing the results obtained with it in subject groups with high and low probabilities of disease. We conclude that although some patients in the former group can be identified, the test is neither sufficiently sensitive nor specific for routine clinical use.     

冠心病早期诊断中磁共振药物负荷心肌灌注成像的应用

目的:研究药物负荷磁共振心肌成像在冠心病早期诊断中的应用价值。方法:34例经冠状动脉造影确诊的患者,静脉注射腺苷前后进行心脏磁共振扫描,观察药物负荷对心肌灌注的影响。结果:①冠状动脉狭窄造成的心肌缺血性改变,在MRI心肌灌注中表现为灌注减低和延迟扫描无增强;②腺苷药物负荷试验可加重心肌缺血性改变,提高心肌灌注减低检测的阳性率,在<50%、50%～75%、>75%的3组冠状动脉狭窄患者中,50%～75%狭窄组增加的阳性率最为明显,与其他两组间有统计学意义(P<0.05)。结论:①腺苷药物负荷MRI心肌灌注成像和延迟扫描可用作冠心病早期诊断中的心肌缺血评估,是冠心病早期诊断的灵敏性指标。MRI心肌灌注减低和延迟增强无强化的心肌段,代表其相对应供血冠状动脉有狭窄存在;②3.0T磁共振仪可通过心肌缺血的状况评估,完善指导冠心病的临床诊断和治疗。     

Scintigraphic assessment of regional cardiac sympathetic nervous system in patients with single-vessel coronary artery disease

In coronary artery disease, the cardiac sympathetic nervous system is closely associated with myocardial ischemia. I-123 metaiodobenzylguanidine (MIBG) imaging allows us to assess the cardiac sympathetic nervous system regionally. One-hundred and eleven patients with single-vessel disease underwent regional quantitative analysis of MIBG imaging before successful percutaneous transluminal coronary angioplasty (PTCA), and repeat angiography 6 months after PTCA. Based on the results of the follow-up left ventriculogram, patients were divided into 3 groups: 39 angina pectoris (AP), 48 prior myocardial infarction without asynergy (MI without asynergy) and 24 prior myocardial infarction with asynergy (MI with asynergy). AP and MI without asynergy had significant correlations between uptake parameters and regional washout in the territory of diseased vessels, among which the severity score in AP was the most closely correlated with regional washout (r = 0.79, p < 0.0001). These correlations disappeared in MI with asynergy. To compare regional MIBG parameters in the territory of the diseased vessel as well as in the territories of the other major coronary arteries among the 3 groups, we examined MIBG parameters in 57 patients with left anterior descending artery (LAD) disease selected from among the study patients. Regional washout in the territory of the LAD was significantly higher in the MI without asynergy group than in the other two groups. The left circumflex artery (LCX) region showed significantly reduced MIBG uptake and an increased extent score in the MI with asynergy group compared with the AP group, although only a difference in the extent score existed between the MI with asynergy group and the AP group in the right coronary artery (RCA) region. In addition, the global ejection fraction before PTCA showed a significant negative correlation with each regional washout rate. In this way, regional quantitative analysis of MIBG imaging can detect the regional differences in the cardiac sympathetic nervous system in coronary artery disease, which may be associated with the degree of regional left ventricular dysfunction due to myocardial ischemia.     

Use of coronary calcium scanning for predicting inducible myocardial ischemia: Influence of patients’ clinical presentation

Background  The selection of patients for cardiac stress tests is generally based on assessment of chest pain symptoms, age, gender, and risk factors, but recent data suggest that coronary artery calcium (CAC) measurements can also be used to predict inducible myocardial ischemia. However, the potential influence of clinical factors on the relationship between CAC measurements and inducible ischemia has not yet been investigated. Methods and Results  We prospectively performed CAC scanning in 648 patients undergoing exercise myocardial perfusion single photon emission computed tomography. The frequency of ischemia on myocardial perfusion single photon emission computed tomography was assessed according to CAC magnitude after dividing patients according to chest pain symptom class and Bayesian likelihood of angiographically significant coronary artery disease (ASCAD), Estimates of ASCAD likelihood and CAC scores were poorly correlated. The frequency of inducible myocardial ischemia was very low among patients with a low ASCAD likelihood if CAC scores were less than 400. By contrast, the threshold for increasing ischemia occurred at low CAC scores among patients with a high ASCAD likelihood. When characterized by chest pain classification, asymptomatic and nonanginal chest pain patients had a low frequency of ischemia if CAC scores were less than 400, whereas lower CAC scores did not exclude ischemia among typical angina or atypical angina patients. Conclusions  CAC scores predict myocardial ischemia, with a threshold score of greater than 400 among patients with a low likelihood of ASCAD and those who are asymptomatic or have nonanginal chest pain. These data appear to extend the pool of patients for whom CAC scanning may be useful in ascertaining the need for cardiac stress testing. This study was supported by a grant from the Eisner Foundation, Los Angeles. Calif.     

Specific perfusion pattern in stress 201Tl myocardial scintigraphy of left main coronary artery disease

The usefulness of stress ²⁰¹Tl myocardial scintigraphy for identifying left main coronary artery disease was evaluated with data from 23 patients with 50% or more narrowing of the left main coronary artery and 56 patients with 75% or more narrowing of the major coronary arteries but without left main coronary artery involvement (no left main coronary artery disease). Quantitiative evaluation of stress perfusion scintigrams in all five patients with narrowing of the left main coronary artery of 99% or more showed a characteristic perfusion pattern (left main pattern) of extensive homogeneous defect over the whole anterolateral segment and simultaneous defects in all radii of the high anteroseptal and high posterolateral segments. On the other hand, such a perfusion pattern was noted in only 1 of 18 patients with less than 90% stenosis of the left main coronary artery and in only 1 of 56 patients with no left main coronary artery disease     

Cardiac sympathetic activity pre and post resynchronization therapy evaluated by 123I-MIBG myocardial scintigraphy

Background Imaging with ¹²³I-metalodobenzylguanidine (MIBG) is used for the assessment of cardiac sympathetic activity (CSA). We analyzed CSA before and after cardiac resynchronization therapy (CRT), and correlated these data with CRT response. Methods and Results Thirty patients with chronic heart failure and classic indications for CRT were prospectively studied before and at least 3 months after CRT. The variables analyzed were: QRS width, left-ventricular ejection fraction (LVEF), left-ventricular end-diastolic diameter (LVEDD), heart/mediastinum MIBG uptake ratio (H/M), and washout rate (WR). After CRT, patients were divided into two groups: group 1 (21 patients), responders improving to functional class (FC) I or II; and group 2 (9 patients), nonresponders remaining in FC III or IV. After CRT, only group I showed favorable changes in QRS width (P=.003), LVEF (P=.01), LVEDD (P=.04), and H/M ratio (P=.003). The H/M ratio and WR were associated with CRT response (P=.005 and P=.04, respectively). The H/M ratio was the only independent predictor of CRT response (P=.01). Receiver operating characteristic curves showed that the optimal H/M ratio cutoff point was 1.36 (sensitivity, 75%; specificity, 71%). Conclusions Improvement in CSA correlated with a positive CRT response. Lower MIBG uptake before therapy was associated with CRT nonresponse. The H/M ratio could be helpful in selecting patients for CRT.     

Myocardial scintigraphy with iodine-123 phenylpentadecanoic acid and thallium-201 in patients with coronary artery disease: a comparative dual-isotope study

To characterise the clinical usefulness of serial myocardial scintigraphy with iodine-123 phenylpentadecanoic acid (IPPA) in comparison with thallium-201, dual-isotope investigations were performed in 41 patients with angiographically documented coronary artery disease. Both tracers were administered simultaneously during symptom-limited ergometry. Planar scintigrams were acquired immediately after stress, and delayed imaging was performed after 1 h for IPPA and 4 h for ²⁰¹Tl. Scintigrams were evaluated both qualitatively and quantitatively using a newly developed algorithm for automated image superposition. Initial myocardial uptake of both tracers was closely correlated (r=0.75, p<0.001). Both tracers also revealed a similar sensitivity for the identification of individual coronary artery stenoses 75% (IPPA: 70.0%, ²⁰¹Tl: 66.3%, P=NS) with identical specificity (69.8%). The number of persistent defects, however, was significantly higher with IPPA (P=0.021), suggesting that visual analysis of serial IPPA scintigrams may over-estimate the presence of myocardial scar tissue. On the other hand, previous Q wave myocardial infarction was associated with a decreased regional IPPA clearance (29% ± 11% vs 44%±11% in normal myocardium, P<0.05). The data indicate that serial myocardial scintigraphy with IPPA is essentially as sensitive as scintigraphy with ²⁰¹Tl for the detection of stress-induced perfusion abnormalities. Quantitative analysis of myocardial IPPA kinetics, however, is required for the evaluation of tissue viability.This study was supported by a grant from the Deutsche Forschungsgemeinschaft/Bonn within the SFB 320 Herzfunktion und ihre Regulation, Ruprechts-Karls University, Heidelberg     

CT angiography unmasking catheter-induced spasm as a reason for left main coronary artery stenosis

Invasive catheterization can lead to mechanically induced spasm of coronary arteries. In this case report, CT angiography allowed us to unmask catheter-induced coronary spasm as the underlying reason for isolated left main coronary artery stenosis seen in invasive angiography.     

Accuracy of stress Tc-99m tetrofosmin myocardial perfusion tomography for the diagnosis and localization of coronary artery disease in women

Background  Earlier studies have suggested a modest accuracy of stress thallium 201 myocardial perfusion imaging (MPI) for the diagnosis of coronary artery disease (CAD) in women. The accuracy of stress MPI with technetium 99m tetrofosmin has not been studied in women. The aim of this study was to assess the accuracy of stress Tc-99m tetrofosmin MPI for the diagnosis and localization of CAD in women. Methods and Results  We studied 88 women who underwent exercise or dobutamine stress Tc-99m tetrofosmin tomography and coronary angiography within 3 months. Significant CAD was defined as a stenosis 50% or greater in diameter in at least 1 major epicardial coronary artery. Myocardial perfusion abnormalities were detected in 44 of 53 patients with significant CAD and in 7 of 35 patients without significant CAD (overall sensitivity, 83% [95% confidence interval (CI), 73%-93%]; specificity, 80% [95% CI, 67%-93%]; and accuracy, 82% [95% CI, 74%-90%]). The sensitivity was 72% (18/25) in patients with single-vessel CAD and 93% (26/28) in patients with multivessel CAD. Perfusion abnormalities were detected in 2 or more vascular distributions in 20 of 28 patients with multivessel CAD and in 4 of 60 patients without multivessel CAD (sensitivity for the identification of multivessel CAD, 71% [95% CI, 55%-88%]; specificity, 93% [95% CI, 86%-98%]; and accuracy, 86% [95% CI, 79%-93%]). The sensitivity, specificity, and accuracy were 82%, 84%, and 83%, respectively, for the diagnosis of CAD in the left anterior descending artery; 77%, 84%, and 81%, respectively, for CAD in the right coronary artery; and 74%, 80%, and 78%, respectively, for CAD in the left circumflex artery. Conclusion  Stress Tc-99m tetrofosmin MPI is an accurate noninvasive technique for the diagnosis and localization of CAD in women. Supported in part by a publication grant from GE Healthcare     

心肌灌注显像联合冠状动脉钙化积分诊断冠心病的价值及最新进展

心肌灌注显像（MPI）在冠心病的诊断、危险度分层及预后评价中扮演着越来越重要的角色,冠状动脉钙化积分（CACS）可协助对冠心病患者进行进一步的危险度分层,但两者有各自的局限性和不足。将两者联合应用可以相互弥补不足,为临床提供更多的信息。行SPECT/CT心肌灌注显像时,需进行衰减矫正CT（CTAC）扫描,若采用心电门控的呼气末屏气螺旋CT扫描,则在用于MPI衰减矫正的同时又可用于CACS测定,实现一站式检查,在减少患者辐射剂量的同时又可为临床提供更多的信息。笔者综述了CACS、MPI及两者联合应用的临床价值,并对一站式采集MPI与CACS的最新进展进行了综述。     

多层螺旋CT无创性冠状动脉造影对冠状动脉疾病的诊断价值

目的:探讨16层螺旋CT冠状动脉造影对冠状动脉病变的临床诊断价值。方法:57例疑似冠状动脉病变的患者行16排螺旋CT检查和冠状动脉造影,不包括5例为冠状动脉支架置入术后(支架12个)。将冠状动脉分为13个节段,分析所有管腔大于2mm的节段,评价图像是否能满足管腔评价。管腔狭窄大于50%认为有意义,以常规冠状动脉造影作为金标准,比较16层螺旋CT在诊断有意义的冠状动脉狭窄方面的敏感性、特异性、阳性预测值、阴性预测值。结果:在所有638个节段中,588个节段(占92.16%)能够满足冠状动脉管腔评价。对于16层螺旋CT能够显示有意义冠状动脉狭窄,与ICA相对照,若以动脉节段计数,MSCT显示中度以上狭窄的敏感性、特异性、阳性预测值、阴性预测值和准确度分别为93.61%、91.11%、89.79%、98.12%和94.63%。以动脉主干计数,MSCT显示中度以上狭窄的敏感性、特异性、阳性预测值、阴性预测值和准确度分别为92.82、、91.31%、80.43%、97.37%和82.08%。以患者计数,MSCT显示中度以上狭窄的敏感性、特异性、阳性预测值、阴性预测值和准确度分别为94.73%、90.00%、93.01%、92.99%和82.75%。结论:16层螺旋CT结合回顾性心电门控技术冠状动脉成像无创、简单易行。既能显示管腔情况又能显示冠脉管壁,弥补了ICA的不足;经严格控制影响因素,具有较高的敏感性和特异性,较高的阴性预测值可避免不必要的有创性检查。对支架术后的随访也有较高的应用价值,对血管变异的显示直观确切。可作为一种有效的筛查和随访手段应用于临床。     

A comparison of dobutamine and maximal exercise as stress for thallium scintigraphy

In the assessment and evaluation of patients with suspected coronary artery disease there is a need for pharmacological stress combined with thallium scintigraphy. Thallium images were obtained following stress both with dobutamine infusion (5–20 g kg^–1 min^–1) and with symptom-limited bicycle ergometry in 20 patients (age 39–70 years) with chest pain who had been admitted for coronary angiography. Percentage thallium uptake was calculated using a region of interest technique. Detailed comparison was performed of the presence, size and distribution of left ventricular thallium perfusion defects; the percentage thallium uptake in ventricles, lung and liver; and the haemodynamic response to stress. Each stress produced a similar number of abnormal segments in each of three views (total EX 166/300; DOB 167/295), but exercise produced larger defects in the anterior view (P<0.025). Thallium uptake in left and right ventricles and relative uptake to lungs were similar, but dobutamine produced higher relative liver uptake [EX 1.55 (0.67); DOB 2.97 (1.23) P<0.0001]. Fourteen patients were able to tolerate dobutamine 20 g kg^–1 min^–1. The ratio of peak stress to rest double product was smaller with dobutamine in both patients with (DOB 1.3; EX 2.0; P<0.0047) and patients without -blockade (DOB 1.5; EX 2.4; P<0.008). Dobutamine produced fewer conventional stress endpoints of chest pain and ST depression. In conclusion, dobutamine produces a well-tolerated incremental pharmacological stress with thallium images similar to maximal exercise, and provides a useful alternative stress in patients unable to perform adequate dynamic exercise.Correspondence to: D.R. Wallbridge     

负荷心肌灌注显像与双源CT冠脉成像诊断冠心病的对比研究

目的:通过对心肌灌注显像(MPI)与心脏双源CT(DSCT)检查结果进行对比分析,探讨两者对冠心病的临床诊断价值.方法:对38例拟诊为冠心病的患者行MPI及心脏DSCT检查;分别对MPI图像及DSCT图像进行分析处理,其中29例经冠状动脉造影(CAG)证实为冠心病.结果:DSCT显示有29例冠脉狭窄程度＞50％,其中大...     

飞行员冠状动脉痉挛致急性心肌梗死一例并文献复习

目的 探讨飞行员冠状动脉痉挛(coronary artery spasm,CAS)致急性心肌梗死(acute myocardial infarction,AMI)的临床特征、诱发因素、诊断、治疗及医学鉴定. 方法 分析1例直升机飞行员冠状动脉痉挛致急性心肌梗死的病史、临床诊断、治疗过程及医学鉴定结论,并进行相关文献复习. 结果 本例飞行员有大量饮酒、吸烟、高血脂、疲劳等多种诱发因素;临床表现为心前区疼痛,胸闷,左肩及左臂发麻,出汗;心电图及心肌酶谱符合急性心肌梗死演变过程;冠状动脉造影未见粥样硬化狭窄,造影过程中发生左冠状动脉全程僵硬,左前降支中段95％狭窄,右冠状动脉僵硬;左、右冠状动脉内推注硝酸甘油后僵硬及狭窄缓解,考虑为冠状动脉痉挛,痉挛血管与心肌梗死部位吻合,证实心肌梗死由CAS所致.该飞行员病后无明显并发症,心电图大致正常,超声心动图正常.经积极控制诱发因素,其病情稳定,未再出现心前区不适等症状,能正常参加体能训练,地面观察半年后复查心电图正常,心功能等指标良好,最后结论:飞行合格.安全飞行1年余无任何不适. 结论 CAS可发生于冠状动脉无粥样硬化狭窄基础上,可引起心绞痛、心律失常、急性心肌梗北等;CAS与冠状动脉内皮功能受损有关,其发作往往有饮酒、吸烟、疲劳等诱因,对高危人群应采取积极预防措施.     

Tolerance and diagnostic accuracy of an abbreviated adenosine infusion for myocardial scintigraphy: A randomized, prospective study

BACKGROUND: The objectives of this study were 2-fold: (1) to determine the tolerance of adenosine perfusion tomography with the use of an abbreviated (3-minute) infusion in comparison to the standard (6-minute) infusion, and (2) to assess the relative diagnostic accuracy of a 3-minute adenosine infusion in patients referred for arteriography. An abbreviated adenosine infusion may decrease the frequency and duration of side effects and be a more cost-effective alternative. METHODS AND RESULTS: We prospectively randomized 599 patients undergoing adenosine myocardial perfusion tomography to either a 3-minute or 6-minute adenosine infusion at 140 microg/kg per minute. Among the 599 enrolled patients, 142 subsequently underwent coronary angiography. Patients randomized to the 3-minute adenosine infusion tolerated the procedure better than those randomized to the standard infusion (P <.01). Flushing, headache, neck pain, and atrioventricular block were all significantly less frequent (P <.01) with the abbreviated infusion. Moreover, patients receiving the abbreviated infusion had less hypotension and tachycardia (P <.05). The sensitivity of the test for detection of coronary artery disease was 88% for both the 3- and 6-minute infusions. In patients with abnormal scan results, perfusion defect size was slightly larger in those receiving a 6-minute infusion versus those receiving a 3-minute infusion (P =.05). CONCLUSIONS: An abbreviated 3-minute adenosine infusion, in combination with perfusion tomography, has similar sensitivity for detection of coronary artery disease and is better tolerated than the standard 6-minute infusion.