Autologous bone marrow-derived progenitor cell transplantation for myocardial regeneration after acute infarction

BACKGROUND: Experimental and first clinical studies suggest that the transplantation of bone marrow derived, or circulating blood progenitor cells, may beneficially affect postinfarction remodelling processes after acute myocardial infarction. AIM: This pilot trial reports investigation of safety and feasibility of autologous bone marrow-derived progenitor cell therapy for faster regeneration of the myocardium after infarction. METHODS AND RESULTS: Four male patients (age range 47-68 years) with the first extensive anterior, ST elevation, acute myocardial infarction (AMI), were treated by primary angioplasty. Bone marrow mononuclear cells were administered by intracoronary infusion 3-5 days after the infarction. Bone marrow was harvested by multiple aspirations from posterior cristae iliacae under general anesthesia, and under aseptic conditions. After that, cells were filtered through stainless steel mesh, centrifuged and resuspended in serum-free culture medium, and 3 hours later infused through the catheter into the infarct-related artery in 8 equal boluses of 20 ml. Myocardial viability in the infarcted area was confirmed by dobutamine stress echocardiography testing and single-photon emission computed tomography (SPECT) 10-14 days after infarction. One patient had early stent thrombosis immediately before cell transplantation, and was treated successfully with second angioplasty. Single average ECG revealed one positive finding at discharge, and 24-hour Holter ECG showed only isolated ventricular ectopic beats during the follow-up period. Early findings in two patients showed significant improvement of left ventricular systolic function 3 months after the infarction. There were no major cardiac events after the transplantation during further follow-up period (30-120 days after infarction). Control SPECT for the detection of ischemia showed significant improvement in myocardial perfusion in two patients 4 months after the infarction. Echocardiographic assessment in these two patients also showed significant improvement of systolic function three months after the infarction. CONCLUSION: Preliminary results of the study showed that the transplantation of bone marrow-derived progenitor cells into the infarcted area was safe, and feasible, and might improve myocardial function. Further follow-up will show if this treatment is effective in preventing negative remodeling of the left ventricle and reveal potential late adverse events (arrhythmogenicity and propensity for restenosis).     

Prevalence and prognostic significance of silent myocardial ischemia in patients after myocardial infarction

BACKGROUND/AIM: Silent myocardial ischemia (MI) can be detected in subjects with any symptoms, in patients after myocardial infarction and in coronary patients who have episodes of symptomatic, as well as of silent MI. This study was carried out to evaluate the frequency, characteristics and prognostic significance of silent MI detected in stress echocardiography test in patients after myocardial infarction. METHODS: In 210 patients within three months after myocardial infarction exercise test was performed. In those patients with ischemic ST depression on exercise electrocardiogram, in order to confirm MI stress echocardiography was additionally performed. To assess the incidence of major cariovascular events, all the patients were followed at least five years after the first myocardial infraction. RESULTS: Out of 210 patients 88 (42%) had ischemic response during stress echocardiography test. Out of 88 patients with MI 54 (61%) had anginal pain (patients with symptomatic MI), while 34 (39%) were free of symptoms (patients with silent MI). Level of exercise test, heart rate, time to the onset of ST segment depression, and the magnitude of ST segment depression were similar in both subgroups of the patients with MI. Duration of exercise test was longer in patients with silent MI (p < 0.05). Wall motion score index during stress echocardiography was higher in patients with symptomatic MI (p < 0.05). Coronary angiography findings were similar in patients with silent and those with symptomatic MI. During a five-yearsfollow-up period the occurrence of major cardic events (cardiac mortality and recurrent myocardial infarction) was similar in both subgroups of the patients with MI. CONCLUSION: In more than one third of patients after myocardial infarction silent MI during stress echocardiography was detected. The patients with silent ischemia had longer duration of exercise test and smaller wall motion score index on stress echocardiography. There was no difference in coronary angiography finding between patients with silent and those with symptomatic MI. The incidence of major cardiac events during a five- years- follow-up was similar in the patients with silent and those with symptomatic MI.     

Emission tomography with 99mTc-pyrophosphate in the diagnosis of acute myocardial infarction

Electrocardiograms (ECG) and enzyme criteria are usually used to confirm the diagnosis of acute myocardial infarction in the case of chest pain. However, ECG is not always diagnostic. Elevated enzyme values may be due to causes other than myocardial infarction. In uncertain cases, the ECG and enzyme criteria can be supplemented by emission tomography, performed with technetium pyrophosphate that will accumulate in the site of infarction. Twenty-nine patients with suspected acute myocardial infarction were studied with emission tomography. Of these 12 had acute transmural infarction. Both enzyme tests and ECG were diagnostic in only 7 of these 12 cases, 4 had positive enzyme tests but a nondiagnostic ECG and in one case neither enzymes nor ECG were diagnostic. In 11 patients the infarcted myocardial area was detected with emission tomography. Six patients had acute nontransmural infarction. Only 2 of these had positive emission tomography. The chest pain was not due to infarction in 11 patients. All these patients had negative emission tomography. The sensitivity of emission tomography was 92% and specificity 100% in transmural acute infarction. In nontransmural infarction the specificity was only 33%. Emission tomography is a valuable diagnostic tool. It may be the decisive method when ECG and enzymes are not diagnostic. Emission tomography also shows the localization and size of the infarcted area in the myocardium.     

Exercise myocardial perfusion imaging in elderly patients

BACKGROUND: Exercise myocardial perfusion imaging (MPI) has significant value for risk stratification, but most patients studied have been middle-aged. In particular, the value of exercise MPI in elderly patients with interpretable electrocardiographic (ECG) stress test results has not been well defined. MEHODS AND RESULTS: Clinical, ECG stress test, MPI, and follow-up data for 626 outpatients aged 65 years or older with interpretable electrocardiograms undergoing symptom-limited exercise MPI between 1992 and 1996 were analyzed. Follow-up was 97% complete after 4.4 +/- 1.3 years. After exclusion of the 27 patients who underwent revascularization within 90 days of MPI, there were 361 men and 217 women, aged 70.7 +/- 4.4 years. By univariate analysis, male sex, increasing age, an abnormal rest ECG result, lower exercise tolerance and lower peak exercise heart rates, exercise ST-segment depression, left ventricular dilatation, and the number of ischemic regions predicted death or myocardial infarction. By multivariable modeling, only increasing patient age, male sex, limitation of exercise tolerance, and the number of ischemic segments by MPI were predictive of subsequent death or myocardial infarction. CONCLUSIONS: In elderly patients referred for exercise MPI, age, sex, exercise tolerance, and MPI ischemia provide significant prognostic information.     

The usefulness of 123I-BMIPP myocardial SPECT in diagnosis for silent myocardial ischemia induced by vasospasm

This study was designed to evaluate the clinical usefulness of 123I-BMIPP myocardial SPECT in patients with silent myocardial ischemia induced by vasospasm. Ultrasonic echocardiography (UCG), Holter electrocardiogram recording (Holter ECG), exercise 201Tl myocardial SPECT (EX-Tl) and rest 123I-BMIPP myocardial SPECT (BMIPP) were performed in 8 patients with asymptomatic vasospasm without history of myocardial infarction. The sensitivity of each modality in detecting coronary artery spasm was 37.5% (3 of 8 cases) for UCG, 37.5% (3 of 8 cases) in Holter ECG, 25.0% (2 of 8 cases) in Ex-Tl, 62.5% (5 of 8 cases) on initial BMIPP images and 75.0% (6 of 8 cases) on delayed BMIPP images. Severity of regional left ventricular wall motion abnormality in UCG correlated with the severity of regionally decreased tracer uptake in BMIPP. The washout rate of BMIPP was 18.7 +/- 2.4 in normal controls, 32.4 +/- 5.9 in asymptomatic vasospasm, and 38.2 +/- 4.0 in asymptomatic vasospasm with abnormal left ventricular wall motion. It was suggested that 123I-BMIPP myocardial SPECT might be useful for assessing asymptomatic vasospasm.     

Late ventricular potentials in risk assessment of the occurrence of complex ventricular arrhythmia in patients with myocardial infarction and heart failure

AIM: To determine the prognostic significance of late ventricular potentials on signal-averaged electrocardiogram and left ventricular ejection fraction for the occurrence of complex ventricular arrhythmia in patients treated with accelerated tissue-type plasminogen activator, using the rapid protocol, within six months of acute myocardial infarction. METHODS: In this analytic observational prospective study patients were divided into four groups: patients with left ventricular ejection fraction bellow 40% and late ventricular potentials, patients with left ventricular ejection fraction bellow 40% and without late ventricular potentials, patients with left ventricular ejection fraction over 40% and late ventricular potentials, and patients with left ventricular ejection fraction over 40% and without late ventricular potentials. Complex ventricular arrhythmias (Lown grade IVa, IVb, and V) were recorded using standard electrocardiography and 24-hour Holter monitoring 21, 60, and 90 days after acute myocardial infarction, respectively. Serial recordings of signal-averaged electrocardiogram were obtained 30, 90, and 180 days after acute myocardial infarction. Left ventricular ejection fraction was determined by echocardiography between 15 and 21 days after acute myocardial infarction. Multivariant logistic regression analysis was used to evaluate the relation between late ventricular potentials and left ventricular ejection fraction with the occurrence of complex ventricular arrhythmias. Sensitivity, specificity, positive and negative predictive values of late ventricular potentials and left ventricular ejection fraction for the occurrence of complex ventricular arrhythmias were determined. RESULTS: The prospective study included 80 patients (73% men), mean age 64 +/- 3.5 years. Complex ventricular arrhythmias were recorded in 34 (42.5%) of patients, all 17 (50%) of which were from the first group (p < 0.01). Complex ventricular arrhythmias were recorded in 25 (73.5%) patients with late ventricular potentials, and in 23 (67.6%) patients with left ventricular ejection fraction bellow 40%. Left ventricular ejection fraction bellow 40% and late ventricular potentials represented independent predictors for the occurrence of complex ventricular arrhythmias (RR = 14.33, p < 0.01). When combined with left ventricular ejection fraction bellow 40%, late ventricular potentials had sensitivity (0.50), specificity (0.93), and positive predictive accuracy (0.85) higher than late ventricular potentials alone (0.44, 0.67, and 0.37, respectively) for the occurrence of complex ventricular arrhythmias following acute myocardial infarction. CONCLUSION: In this study, late ventricular potentials in patients with left ventricular ejection fraction bellow 40% represented the independent predictor for the occurrence of complex ventricular arrhythmias in the first six months after the first myocardial infarction treated with accelerated tissue-type plasminogen activator, using the rapid protocol.     

双源CT双能量心肌灌注对诊断心肌梗塞及其罪犯血管关系的研究

目的 探讨双源CT双能量心肌灌注对心肌梗塞的诊断价值及其与罪犯血管的关系.方法 用双源CT双能量灌注成像方法对42例临床疑诊或确诊为冠心病的患者进行扫描.分析心肌灌注情况与罪犯冠脉狭窄程度的关系;对19例临床确诊为陈旧性心梗患者的心电图与心肌灌注情况进行了对比分析.结果 42例患者的心肌灌注改变与冠脉狭窄程度存在线性变化趋势(P＞0.05),11例冠脉轻及中度狭窄患者心肌灌注未见异常,31例重度及完全闭塞患者,26例可见心肌灌注减低;19例临床确诊为陈旧性心梗患者心电图均见病理性Q波、心肌灌注均有缺损.结论 双源CT双能量心肌灌注成像.可一站式评价冠心病心肌缺血或梗死情况及其与罪犯血管的关系,对冠心病的诊断、治疗及预后评估具有重要指导意义.     

99Tcm-MIBI静息心肌断层显像对年轻心肌梗死患者心肌损伤的评价

目的　用99Tcm 甲氧基异丁基异腈 (MIBI)静息SPECT显像评价年轻心肌梗死患者的心肌损伤。方法　总结分析了 42例年龄 <40岁的心肌梗死患者99Tcm MIBI静息心肌灌注断层显像 ,并与冠状动脉造影和ECG进行比较。结果　 42例年轻心肌梗死患者 ,90 % (38例 )心肌灌注显像异常 ,10 % (4例 )未见明显异常 ,诊断灵敏度为 90 %。与ECG相比 ,心肌灌注显像对梗死灶定位更准确 ,特别是心尖和后壁梗死。结论　心肌灌注显像显示年轻心肌梗死患者心肌受损较严重。     

Prognostic value of myocardial ischemia in patients with uncomplicated acute myocardial infarction: direct comparison of stress echocardiography and myocardial perfusion imaging.

This study directly compared the prognostic value of predischarge dobutamine stress echocardiography (DSE) and dobutamine myocardial SPECT perfusion imaging in patients with prior myocardial infarction. METHODS: The study population consisted of 146 consecutive patients who underwent predischarge DSE and SPECT with (99m)Tc-sestamibi after a first acute uncomplicated myocardial infarction treated with thrombolysis. Fifty patients who underwent revascularization within 90 d from the imaging studies were excluded. Cardiac death and nonfatal myocardial infarction were considered events. Follow-up was 98% complete in a mean period of 44 +/- 19 mo. RESULTS: Myocardial ischemia was detectable in 55 (58%) patients at SPECT and in 63 (67%) patients at DSE. Concordance between SPECT and DSE in detecting ischemia was observed in 68 (72%) of the 94 patients (kappa value, 0.41). During the follow-up, there were 20 cardiac events (9 deaths and 11 nonfatal myocardial infarctions). Ischemia at SPECT was a significant predictor of events (hazards ratio = 4.8; 95% confidence interval, 1.4-16.3; P < 0.01). However, ischemia at DSE (biphasic or worsening patterns) was not associated with events, whereas biphasic pattern alone was associated with a poor outcome compared with direct worsening (P < 0.05). Finally, at Cox multivariate analysis, ischemia at SPECT but not biphasic pattern at DSE was a significant independent predictor of events (P < 0.01). CONCLUSION: These results indicate that, after uncomplicated myocardial infarction, ischemia at SPECT is associated with an increased risk of cardiac events at long-term follow-up. However, ischemia at DSE was unable to stratify patients after myocardial infarction.     

Myocardial adrenergic derangement due to myocardial ischemia: decreased myocardial uptake of I-123 metaiodobenzylguanidine after PTCA in a patient with effort angina

Regional denervation of adrenergic nerves has been clinically demonstrated in patients with myocardial infarction using I-123 metaiodobenzylguanidine (MIBG) scintigraphy. However, it is not clarified whether adrenergic denervation can be induced by prolonged myocardial ischemia as well as by myocardial infarction. This case with effort angina had 99% stenosis of right coronary artery and showed perfusion defects at inferior myocardial regions in the exercise thallium-201 study. However, inferior wall motion estimated by echocardiography and left ventriculography was normal indicating the absence of myocardial infarction. After percutaneous transluminal coronary angioplasty for the stenosis, I-123 metaiodobenzylguanidine (MIBG) and thallium-201 (Tl-201) myocardial scintigraphies were done to estimate the therapeutic effect of PTCA. Although the Tl-201 study during exercise showed normal findings indicating the success of PTCA, marked defects was detected at inferior myocardial regions in the I-123 MIBG studies just after and 4 hours after an intravenous injection of I-123 MIBG. These results suggest that adrenergic derangement may be induced by prolonged myocardial ischemia and may persist for periods even though myocardial perfusion is normalized.     

Tomographic myocardial perfusion scintigraphy in children with Kawasaki disease

Myocardial infarction and stenotic coronary lesions are serious late complications in children with Kawasaki disease. For the noninvasive assessment of myocardial perfusion, dipyridamole-redistribution 201Tl emission computed tomography (ECT) was performed in seven children (age 2 8/12-8 7/12 yr) 3-20 mo after the acute stage of the disease. In all patients, coronary aneurysms had been demonstrated by cross-sectional echocardiography. The scintigrams of six children showed no significant regional reduction of myocardial thallium uptake. These children had remained asymptomatic since the acute stage of Kawasaki disease. Persistent and transient thallium defects were present in one child with documented myocardial infarction. For this patient, obstruction of corresponding coronary vessels was confirmed by contrast angiography. It is suggested, that 201Tl ECT after dipyridamole-induced vasodilation may be used as a safe alternative to invasive coronary angiography for follow-up investigations in patients with Kawasaki disease.     

Myocardial enhancement pattern in patients with acute myocardial infarction on two-phase contrast-enhanced ECG-gated multidetector-row computed tomography

AIM: To evaluate the myocardial enhancement pattern of the left ventricle on two-phase contrast-enhanced electrocardiogram (ECG)-gated multidetector computed tomography (MDCT) images in patients with acute myocardial infarction (AMI). METHODS: Two-phase contrast-enhanced ECG-gated MDCT examinations were performed in 16 patients with AMI. The presence, location and pattern of myocardial enhancement were evaluated. MDCT findings were compared with the catheter angiographic results. RESULTS: Subendocardial (n = 9) or transmural (n = 6) area of early perfusion defects of the myocardium was detected in 15 of 16 patients (94%) on early-phase CT images. Variable delayed myocardial enhancement patterns on late-phase CT images were observed in 12 patients (75%): (1) subendocardial residual perfusion defect and subepicardial late enhancement (n = 6); (2) transmural late enhancement (n = 1); (3) isolated subendocardial late enhancement (n=1); and (4) isolated subendocardial residual perfusion defect (n = 2). On catheter angiography, 14 of 15 corresponding coronary arteries showed significant stenosis. CONCLUSION: Variable abnormal myocardial enhancement pattern was seen on two-phase, contrast-enhanced ECG-gated MDCT in patients with AMI. Assessment of myocardial attenuation on CT angiography gives additional information of the location and extent of infarction.     

Scintigraphic, electrocardiographic, and enzymatic diagnosis of perioperative myocardial infarction in patients undergoing myocardial revascularization.

To assess the incidence of perioperative myocardial infarction, 214 consecutive patients were evaluated 1-5 days after coronary bypass surgery, using Tc-99m pyrophosphate (TcPPi) myocardial imaging, serial electrocardiograms (ECG), and enzyme levels (SGOT, LDH, CPK). On the basis of the clinical course and scintigraphic, enzymatic, and ECG changes, the diagnosis of perioperative infarction was definite in 17 of 241 cases (7.9%) and probable in six of 241 (2.8%). In all of these 23 patients, TcPPi scans were abnormal; one additional patient had a false-positive scintigram. Only 13 of the 23 had ECG evidence of infarction, but there were no false positives. We set the threshold for abnormality of enzyme changes quite high, owing to experience in more than 900 postoperative patients (SGOT greater than 200, LDH greater than 500, CPK greater than 500 on the same day). Using these criteria, 22 of the 23 infarct patients had abnormal enzymes, and six others were falsely positive. These results indicate a relatively low sensitivity for the ECG in diagnosing perioperative infarction, but the lack of false positives suggests high specificity. The sensitivity and specificity of the enzymes and the TcPPi image were both excellent and quite similar; the main difference was a reduction of certainty of infarction with the enzyme criteria, caused by the six patients whose enzyme values were falsely positive. Considering its sensitivity, specificity, and ability to locate and to a certain extent quantitate necrosis. TcPPi imaging is probably the most valuable means of diagnosing perioperative myocardial infarction.     

前列地尔对冠状动脉介入术后无复流患者左心室功能和心血管事件的影响

目的：观察前列地尔脂微球载体制剂（Lipo-PGE1）对急性广泛前壁心肌梗死并完全性右束支传导阻滞（RBBB）经冠状动脉介入治疗（PCI）后无复流患者左心室功能和心血管事件的影响。方法：102例确诊急性广泛前壁心肌梗死并完全性RBBB的患者,且所有患者均从发病至到达我院行直接PCI时间〈12h,术后血流只达到TIMI2级,且完全性RBBB仍存在,予随机分为治疗组及对照组。治疗组予生理盐水20mL加Lipo-PGE120μg静脉缓慢推注2次/d,共3d;对照组予硝酸甘油用5%葡萄糖稀释（糖尿病患者用生理盐水）50～100μg/min持续静脉缓慢滴注3d。两组患者均予心电监护、心电图检查及彩色多普勒二维结果：治疗组与对照组在术后住院期间LVDd、LVEF均无显著性差异。随访1年,治疗组患者的LVDd明显降低,LVEF明显提高,与对照组相比差异均有显著性,P〈0.05;术后1周内治疗组中完全性RBBB消失的例数多于对照组,室性心动过速的病例数少于对照组,差异有显著性,P〈0.05。结论：对于急性心肌梗死患者经PCI术后存在无复流现象,经应用Lipo-PGE1可改善心肌微循环,挽救更多濒死心肌,减少心律失常发生,从而达改善心泵功能,提患者生活质量。     

急性心肌梗死心肌血流再灌注评价技术

TIMIFlow作为评价再灌注的方法自20世纪80年代起就一直应用于临床。TIMIFrameCount是较TIMI血流分级更为客观、更具可重复性的联系性变量指标。TMBG和TMP从心肌微血管水平对再灌注进行评价。冠脉内多普勒血流频谱变化常作为造影过程中的附加检查指标评价血管再通及心肌再灌注。同时心肌声学造影、连续心电图ST段监测、核素心肌灌注显像和心肌增强磁共振成像作为无创性的评价方法也显示出其应用价值。     

Heart tomography with 99mTc sestamibi and echocardiography with dobutamine in the identification of reversible left ventricular dysfunction in patients with acute myocardial infarction]

INTRODUCTION: We investigated the role of technetium-99m (99mTc) sestamibi cardiac imaging and dobutamine echocardiography in detecting myocardial viability early after acute myocardial infarction. MATERIAL AND METHODS: Nineteen patients (mean age 52 +/- 10 years) underwent coronary angiography, low-dose dobutamine echocardiography and rest 99mTc sestamibi imaging within 10 days of myocardial infarction. All patients were revascularized. Resting echocardiogram was repeated 8 months later to evaluate segmental functional recovery. RESULTS: Sixty-one of 108 akinetic or dyskinetic segments at baseline showed functional recovery after revascularization. Sensitivity in predicting segmental functional recovery was 87% for sestamibi imaging and 66% for dobutamine echocardiography (p < 0.001), while specificity and accuracy were comparable. Sestamibi activity was the strongest predictor of segmental functional recovery (p < 0.001). CONCLUSIONS: Dobutamine echocardiography predicts functional recovery after myocardial infarction. However, sestamibi imaging is useful to identify patients with dysfunctional segments without contractile reserve which may benefit by revascularization.     

冠状动脉造影正常的心肌梗死患者~(99)Tc~m-MIBI心肌灌注显像

目的　探讨99Tcm 甲氧基异丁基异腈 (MIBI)心肌灌注断层显像 (MPI)对冠状动脉造影(CAG)正常的心肌梗死 (MI)患者的临床应用价值。方法　 5例患者中 4例为急性MI,1例为异常Q波原因待查 ,均经CAG证实冠状动脉正常。于CAG后 7～ 10d行运动 静息99Tcm MIBIMPI。结果　 5例患者中 4例MPI异常 (均为固定放射性缺损 ) ,1例正常。 1例异常Q波待诊患者经MPI确诊为MI。4例MPI显示的MI部位较ECG大 ;1例ECG示透壁性MI者MPI正常。随访期间 ,1例因心功能不全行室壁瘤切除术。结论　99Tcm MIBIMPI对CAG正常的MI诊断及梗死部位、程度和预后的判断有较高价值     

Dobutamine stress thallium-201 single-photon emission tomography versus echocardiography for evaluation of the extent and location of coronary artery disease late after myocardial infarction.

Dobutamine stress echocardiography and thallium-201 myocardial perfusion scintigraphy are clinically useful methods for the evaluation of coronary artery disease (CAD). However, the relative merits of these imaging modalities in the evaluation of the extent of CAD after myocardial infarction have not been well studied. The aim of this study was to compare the accuracy of dobutamine stress echocardiography and simultaneous 201Tl single-photon emission tomography (SPET) imaging for the diagnosis and localization of CAD late after acute myocardial infarction. Dobutamine (up to 40 micrograms kg-1 min-1)-atropine (up to 1 mg) stress echocardiography in conjunction with stress-reinjection 201Tl SPET was performed for the evaluation of myocardial ischaemia in 90 patients with previous myocardial infarction who underwent coronary angiography. Significant CAD was predicted on bases of myocardial ischemia (new or worsening wall motion abnormalities on echocardiography and reversible perfusion defects on 201Tl SPET). Significant CAD (> or = 50% luminal diameter stenosis) was detected in 73 (81%) patients. The sensitivity, specificity and accuracy of echocardiography in detecting remote ischaemia for the diagnosis of remote CAD (present in 53 patients) were, respectively, 79% (CI 70%-88%), 85% (CI 77%-93%) and 81% (CI 73%-90%), while the corresponding figures for 201Tl SPET were 75% (CI 66%-85%), 78% (CI 69%-87%) and 76% (CI 67%-86%) respectively (P = NS vs echocardiography). The sensitivity, specificity and accuracy of echocardiography in detecting peri-infarction ischaemia for the diagnosis of infarct-related artery stenosis (present in 70 patients) were, respectively, 77% (CI 68%-86%), 85% (CI 78%-92%) and 79% (CI 70%-87%) while the corresponding figures for 201Tl SPET were 73% (CI 64%-82%), 85% (CI 78%-92%) and 76% (CI 67%-84%) respectively (P = NS vs echocardiography). The agreement between the two methods for the diagnosis of peri-infarction and remote ischaemia was 70% (kappa = 0.37) and 80% (kappa = 0.59) respectively. It is concluded that dobutamine stress echocardiography and 201Tl SPET have comparable accuracy for the diagnosis of infarct related and remote CAD in patients with previous myocardial infarction. The agreement between the methods is higher for the diagnosis of remote CAD than for that of peri-infarction ischaemia.     

Acute myocardial infarction in a patient with unstable angina

A 58-year-old-man with unstable angina developed a violent retrosternal and interscapular pain during coronary angiography with no associated ECG abnormalities. The patient was immediately submitted to transesophageal echocardiography, which revealed an echo-free space behind the ascending aorta thought to be consistent with an aortic dissection. To confirm this finding the patient underwent contrast-enhanced helical CT, which ruled out a dissection but revealed a small hypoattenuating, ill-defined area within the lateral wall of the left ventricle, consistent with an acute myocardial infarction. The finding was first confirmed by bedside echocardiography and later validated by laboratory tests. Review of the left coronary angiogram showed the culprit lesion at the origin of a major acute marginal branch of the circumflex artery.     

左心室肥厚并急性心肌梗死室性电风暴心电图对预后的影响

目的 探讨沿海居民高血压性左室肥厚(left ventricular hypertrophy,LNH)并急性心肌梗死(acute myocardial infarction,AMI)后心电图特征性改变,评估室性电风暴与临床预后危险分层.方法 选择急诊住院有高皿压性LVH并AMI室性电风暴(室速或室颤)317例(Ⅱ组),另选无高血压性LVH室性电风暴AMI 109例(Ⅰ组)进行心电图检查和持续心电监护,分析心电图特征与临床高危特点.结果 室性电风暴组以高血压LVH并AMI患者心电图指标心房终末电势异常、∑ST段抬高振幅、ST段抬高导联数、QTc间期延长、对应导联ST段振幅下移等特征,梗死部位以前壁或复合前壁,并以左前降支合并回旋支或/和右冠脉完全闭塞多支病变为主,与Ⅰ组比较差异有统计学意义(P<0.05或P<0.01),临床并发泵衰竭、AMI扩展、住院病死率、室性电风暴AMI发病后6 h内发生率明显增多(P<0.01).结论 高血压性LVH并AMI室性电风暴患者,心电图多项指标异常对临床预后有预测作用.