心肌呈色分级评价急性心肌梗死溶栓疗法的疗效

目的以心肌呈色分级(MBG)评估急性心肌梗死溶栓后的心肌灌注状况.方法89例急性心肌梗死患者给予重组组织型纤溶酶原激活剂治疗.各例于给药后90分钟行冠状动脉造影,观察梗死相关动脉前向血流,评估心肌灌注情况,并记录6个月心脏事件发生率.结果溶栓后符合临床再通标准的为87.6%,未再通的为12.4%.冠状动脉造影结果显示,全组梗死相关动脉的再通率(TIMI 2或3级)为82%;心肌再灌注率(MBG 2或3级)为88.8%,完全再通(TIMI 3级)且完全心肌再灌注(MBG 3级)者为40.4%.6个月死亡率为10.1%.多因素分析结果表明,入院时Killip分级和MBG分级是急性心肌梗死死亡的主要独立预测因子(P=0.0001).结论成功的再灌注治疗应该是梗死相关动脉前向血流TIMI 3级且伴良好心肌灌注.     

Effect of preinfarction angina pectoris on myocardial blush grade after reperfusion in first anterior wall acute myocardial infarction.

BACKGROUND: The aim of the present study was to clarify the effect of preinfarction angina pectoris (PIA) on myocardial blush grade (MBG), a simple marker of myocardial tissue-level reperfusion, in acute myocardial infarction (AMI). METHODS AND RESULTS: One hundred forty-two patients with first anterior wall AMI who were admitted within 6 h after onset of symptoms were examined. PIA was defined as typical chest pain within 48 h before onset of symptoms. MBG was evaluated by coronary angiography after reperfusion. Patients with MBG 2 or 3 (n=103) had a higher frequency of PIA and a lower frequency of diabetes mellitus than those with MBG 0 or 1 (n=39) (57% vs 28%, p=0.004, and 23% vs 44%, p=0.03, respectively). The former had a lower peak creatine kinase level and a greater left ventricular ejection fraction at predischarge than the latter (3,652+/-2,440 vs 5,507+/-3,058 IU/L, p=0.0002, and 57+/-12% vs 45+/-11%, p<0.0001, respectively). Multivariate logistic regression analysis showed that PIA (p=0.004) and diabetes mellitus (p=0.03) were independently associated with MBG 2 or 3 after reperfusion. CONCLUSIONS: PIA has beneficial effects on myocardial tissue-level reperfusion evaluated by MBG in first anterior wall AMI.     

Myocardial blush grade: to evaluate myocardial viability in patients with acute myocardial infarction

Myocardial blush grade (MBG) is used to assess myocardial perfusion in the infarcted myocardium. The purpose of this study was to determine whether the analysis of myocardial blush grade after resolution of the acute phase of myocardial infarction is useful for assessing myocardial viability. The present study is consisted of 64 patients (55 men, mean age 55 +/-11 years) who had acute myocardial infarction and nonoccluded stenosis (>50%) in an infarct-related artery. All the patients had thrombolysis in myocardial infarction (TIMI)-3 flow in the infarct-related artery on coronary angiograms. Myocardial viability was determined by single-photon emission computed tomography (SPECT) within the same week after coronary angiograms. MBG 0 in 5 (8%) patients, grade 1 in 10 (16%) patients, grade 2 in 23 (36%) patients, and grade 3 in 26 (40%) patients were present. Fifty-four (84%) of 64 patients showed myocardial viability by SPECT. Myocardial viability was demonstrated in 11 of 15 patients (74%) with MBG 0/1 and 43 of 49 patients (88%) with MBG 2/3. There was a weak relation between MBG and myocardial viability by correlation analysis (r = 0.28, p = 0.025). If MBG 0 and 1 are regarded as a sign of nonviable myocardium, and if MBG 2 and 3 are regarded as a sign of viable myocardium, the sensitivity of MBG for the prediction of myocardial viability was 79%, specificity was 40%, positive predictive value was 88%, and negative predictive value was 27%. MBG has a weak correlation with myocardial viability. Although sensitivity is fairly good, specificity is very low. We concluded that the diagnostic value of MBG is limited to detect myocardial viability in the infarcted region.     

Limitations of myocardial blush grade in the evaluation of myocardial perfusion in patients with acute myocardial infarction and TIMI grade 3 flow

INTRODUCTION AND OBJECTIVES: An analysis was made of variability in the measurement of the angiographic index blush between a university hospital and an independent core laboratory, as well as its correlation with perfusion analyzed by intracoronary myocardial contrast echocardiography (MCE) and the ventricular function at the sixth month. METHODS: The study comprised 40 patients with a first ST-segment elevation myocardial infarction, single-vessel disease and open infarct-related artery. Perfusion was quantified by angiography (median fifth day, range 3-7) with blush in our laboratory and in an independent core laboratory. MCE was performed. Ejection fraction at the sixth month was determined with magnetic resonance imaging. RESULTS: We found a weak correlation (r=0.38) between both laboratories. In the comparison of blush measurements concordance was 80%, kappa=0.43 if normality was defined by blush 2-3; and concordance 55%, kappa=0.1 for blush 3. Neither perfusion analyzed by MCE (r= 0.23, P=.2) nor ejection fraction by resonance (r=0.20, P=.3) did correlate to blush. CONCLUSIONS: After infarction in patients with TIMI 3, variability is observed in blush measurements between a university hospital and an independent core laboratory, therefore it seems advisable to centralize blush measures in highly specialized core laboratories. A weak correlation was detected with perfusion analyzed by MCE and with late systolic function.     

Repeated assessment of coronary flow velocity pattern in patients with first acute myocardial infarction

OBJECTIVES: The aim of this study was to evaluate the coronary blood flow velocity pattern immediately and 24 h after percutaneous transluminal coronary angioplasty (PTCA) for acute myocardial infarction (AMI) in relation to myocardial reperfusion and follow-up left ventricular (LV) function. BACKGROUND: Analysis of coronary blood flow velocity pattern after AMI may provide information about microvascular damage and the occurrence of a reperfusion injury. METHODS: Measurement of coronary blood flow velocity pattern was performed immediately after PTCA and after 24 h in 25 patients with first AMI using a Doppler guidewire. Measurements were related to reperfusion determined by intravenous myocardial contrast echocardiography (MCE) performed before PTCA and at 24 h and to LV function at four weeks. RESULTS: Using MCE, 13 patients showed reperfusion and 12 patients showed nonreperfusion. Compared with patients with reperfusion, patients with MCE nonreperfusion had a lower systolic peak flow velocity immediately after PTCA (10.0 +/- 0.3 cm/s vs. 19.3 +/- 0.8 cm/s, respectively) and after 24 h (12.3 +/- 0.4 cm/s vs. 21.3 +/- 0.1 cm/s, respectively, p = 0.0022), more frequent early systolic retrograde flow (6/12 vs. 0/13, p = 0.0052 immediately after PTCA and 24 h later) and a shorter diastolic deceleration time immediately after PTCA (483 +/- 6 ms vs. 737 +/- 0 ms, respectively) and after 24 h (551 +/- 9 ms vs. 823 +/- 2 ms, respectively, p = 0.0091). Similarly, patients with impaired LV function at four weeks had altered coronary flow pattern compared with patients with preserved function. The coronary flow velocity pattern showed a tendency for improvement after 24 h in the reperfusion and the nonreperfusion groups. CONCLUSIONS: The coronary flow velocity pattern immediately and 24 h after PTCA for AMI relates to myocardial perfusion determined by MCE and LV function at four weeks. The flow velocity pattern shows slight improvement during the first 24 h after revascularization, indicating the absence of a major reperfusion injury.     

Usefulness of myocardial blush grade early and late after primary coronary angioplasty for acute myocardial infarction in predicting left ventricular function

This study sought to analyze the evolution of myocardial perfusion during follow-up after primary angioplasty for acute myocardial infarction (AMI) and relate it to final left ventricular (LV) function. In 101 patients with a first AMI, angiographic myocardial blush grade (MBG) was analyzed immediately after intervention and at follow-up 7.5 +/- 5.6 months later. Cine ventriculography was performed at follow-up angiography to define LV function. Five patients had occluded stents or flow-limiting restenosis. In the remaining patients, myocardial perfusion at follow-up, as defined by MBG, was persistently abnormal in 19 patients (20%), had become normalized from previously abnormal MBG in 30 patients (31%), remained normal in 40 patients (42%), and deteriorated from normal to abnormal in 7 patients (7%). Patients with improvement of abnormal blush determined immediately after intervention to normal blush at follow-up (n = 30) compared with patients with persistently abnormal blush (n = 19) had a better LV ejection fraction at follow-up (53.7 +/- 11.1 vs. 37.4 +/- 9.7%, p <0.001). Evolution of MBG had a better predictive value for LV ejection fraction at follow-up than acute MBG only. Multivariate analysis proved evolution of MBG from AMI to follow-up to be an independent predictor of LV function (R(2) = 0.177, p <0.001) in addition to the initial size of jeopardized myocardium as defined by the sum of ST-segment elevation (R(2) = 0.138, p = 0.001) and infarct location (R(2) = 0.044, p = 0.033). In conclusion, tissue reperfusion after angioplasty for AMI is characterized by frequent improvement over time, as indicated by repeated MBG analysis. Patients with recovery of perfusion have better, final LV function.     

Collateral blood flow can predict myocardial blush grade in primary coronary intervention

Objectives Our aim was to investigate whether collateral flow may predict myocardial blush grade (MBG) in acute myocardial infarction patients undergoing primary percutaneous coronary intervention. Background No‐reflow is a well known phenomenon associated with increased morbidity and mortality due to underperfused myocardium; therefore early prediction of no‐reflow is of major importance. We have observed that in patients with good collateral filling of the infarct related artery as seen prior to primary angioplasty, the clearance of the contrast medium from the myocardium may be impaired. Methods We retrospectively analyzed the MBG as observed by collateral filling in 81 patients and correlated it with the final MBG. Patients were divided into two groups—those with collateral MBG 0 or 1 (34) and those with myocardial blush 2 or 3 (47). Results Of the 34 patients in the first group 71% remained in the same MBG group after primary percutaneous coronary intervention and the rest improved. Of the 47 individuals with collateral MBG 2 or 3, 87% remained in the same group following primary percutaneous coronary intervention, and the rest deteriorated (P < 0.01 for both groups). Conclusions Collaterals may predict MBG in acute myocardial infarction patients undergoing primary percutaneous coronary intervention. © 2011 Wiley Periodicals, Inc.     

Effect of reactive hyperemia after coronary recanalization on myocardial tissue reperfusion by thrombolysis in myocardial infarction flow grade in acute myocardial infarction

Thrombolysis In Myocardial Infarction (TIMI) flow grade is widely used to evaluate myocardial tissue reperfusion in acute myocardial infarction (AMI), but the current grading system is incomplete. Therefore, we clarified the regulation of epicardial coronary flow velocity with the progression of microvascular dysfunction in AMI. We studied 36 patients with first anterior AMI. After intervention, we assessed TIMI flow grade and measured average peak velocity (APV) at baseline and after infusion of adenosine triphosphate (48 microg; baseline and hyperemic APVs, respectively) with a Doppler guidewire. We performed myocardial contrast echocardiography after 2 weeks to assess microvascular integrity (good reflow vs no reflow) and left ventriculography at admission and discharge (24 +/- 2 days) to measure regional wall motion (SD/chord). Patients were classified into 3 groups based on TIMI flow grade and microvascular integrity: TIMI grade 3 flow/good reflow (n = 16), TIMI grade 3 flow/no reflow (n = 12), and TIMI grade 2 flow (n = 8). Baseline APV was comparable in the patients with TIMI grade 3 flow but hyperemic APV was higher in patients with TIMI grade 3 flow/good reflow than in those with TIMI grade 3 flow/no reflow (hyperemic APV 59.3 +/- 25.8 vs 32.8 +/- 8.9 cm/s, p <0.01). All patients with TIMI grade 2 flow showed no reflow and the lowest values of baseline and hyperemic APVs. Regional wall motion at discharge was higher in patients with TIMI grade 3 flow/good reflow than in those with TIMI grade 3 flow/no reflow and TIMI grade 2 flow (-1.44 +/- 0.70, -2.69 +/- 0.31, and -2.88 +/- 0.48 SD/chord, respectively, p <0.01). In conclusion, compensatory reactive hyperemia preserves epicardial coronary flow velocity even in patients with microvascular damage, and with the progression of damage, this compensatory hyperemia can no longer preserve epicardial coronary flow velocity, and baseline APV is decreased in TIMI grade 2 flow.     

Noninvasive assessment of reperfusion after fibrinolytic therapy for acute myocardial infarction

Assessment of reperfusion by the 12-lead electrocardiogram (ECG) or biochemical markers is limited by suboptimal sensitivity and/or specificity. Body surface mapping (BSM) improves the spatial sampling of the 12-lead ECG. Serial 12-lead ECGs and 64-lead anterior BSMs were recorded from 67 patients with acute myocardial infarction undergoing coronary angiography 90 minutes after fibrinolytic therapy. ECG-1 and BSM-1 were recorded before/shortly after therapy (median 18 minutes). ECG-2 and BSM-2 were recorded after the 90-minute angiogram (median 30 minutes). The maximum ST elevation on ECG-1 was noted and > or = 30% ST resolution on ECG-2 was taken to represent partial/complete reperfusion. Patients were randomly divided into a training set and validation set. Isointegral and isopotential ST-T variables from BSMs of training-set patients were compared with Thrombolysis In Myocardial Infarction (TIMI) trial flow using discriminant analysis to identify which variables best classified reperfusion. Reperfusion (TIMI 2/3 flow) occurred in 32 of 34 training-set patients and in 29 of 33 validation-set patients. In the training set, > or = 30% ST resolution correctly classified reperfusion with 72% sensitivity (23 of 32) and 50% specificity (1 of 2). In the validation set, > or = 30% ST resolution classified reperfusion with 59% sensitivity (17 of 29) and 50% specificity (2 of 4). In comparison, a model containing 24 BSM variables correctly classified all training-set patients, and when prospectively tested in the validation-set, correctly classified 28 of 29 patients who achieved reperfusion (97% sensitivity) and all 4 patients who failed to reperfuse (p = 0.035). In conclusion, BSM is more useful than the 12-lead ECG for noninvasive assessment of reperfusion after fibrinolytic therapy for acute myocardial infarction.     

Noninvasive assessment of reperfusion and reocclusion after thrombolysis in acute myocardial infarction

The clinical significance of ST-segment changes and of the time course of appearance in serum of different cardiac proteins has been reviewed for the diagnosis of coronary reperfusion and reoclusion after thrombolysis. In particular, the value of serial 12-lead electrocardiographic (ECG) studies, of Holter monitoring, and of continuous multilead computer-assisted ECG monitoring is compared. Regarding the serum proteins, the clinical significance of reperfusion indices described so far for serum creatine kinase (CK), its isoenzyme serum creatine kinase MB, the CK isoforms, and myoglobin is reviewed. Emphasis is placed on (1) the calculation method used for deriving the reperfusion indices; (2) the sensitivity and the specificity of the reperfusion indices; (3) the minimum turn-around time needed to produce the reperfusion indices (depending on the practicability of the analytical and calculation methods and their applicability in an emergency laboratory); (4) the ability of the indices to produce reliable estimates of reperfusion efficacy of the thrombolytic agents under study; and (5) the ability of the marker proteins to detect reinfarction as well as the suitability of the markers to detect real-time necrosis.     

Quantitative assessment of myocardial blush grade in patients with coronary artery disease and in cardiac transplant recipients

Quantitative assessment of myocardial perfusion by myocardial blush grade(MBG) is an angiographic computer-assisted method to assess myocardial tissue-level reperfusion in patients with acute coronary syndromes and microvascular integrity in heart transplant recipients with suspected cardiac allograft vasculopathy. This review describes the ability of quantitative MBG as a simple, fast and cost effective modality for the prompt diagnosis of impaired microvascular integrity during routine cardiac catheterization. Herein, we summarize the existing evidence, its usefulness in the clinical routine, and compare this method to other techniques which can be used for the assessment of myocardial perfusion.     

Combined prognostic utility of ST-segment recovery and myocardial blush after primary percutaneous coronary intervention in acute myocardial infarction.

AIMS: ST-segment recovery (SigmaSTR) and myocardial blush (MB) evaluate different elements of microcirculatory integrity after reperfusion therapy in acute myocardial infarction (AMI). We sought to determine whether the combination of SigmaSTR and MB after primary percutaneous coronary intervention (PCI) in AMI has greater prognostic utility than either measure alone. METHODS AND RESULTS: The 30 days and 1 year clinical outcomes of 456 patients were assessed as a function of SigmaSTR and MB after primary PCI from the CADILLAC trial. SigmaSTR and MB were concordant (> or =70% SigmaSTR and MB grade 2/3 or <70% SigmaSTR and MB grade 0/1) in 60.1% of patients and discordant in 39.9% of patients. The greatest survival was observed among patients with complete SigmaSTR (> or =70%) and MB grade 2/3 in whom the cumulative rates of death at 30 days and 1 year were 0.6 and 1.2%, respectively. Poorest survival was observed among patients with incomplete SigmaSTR (<70%) and reduced MB (grade 0/1), in whom 30 days and 1 year rates of death were 8.3 and 10.1%, respectively. Intermediate outcomes were present in patients with discordant MB and SigmaSTR. By multivariable analysis, however, SigmaSTR was an independent correlate of survival at 30 days and 1 year (P=0.05 and 0.01, respectively), whereas MB was no longer predictive (P=0.38 and 0.72, respectively). CONCLUSION: SigmaSTR and MB are not infrequently discordant after primary PCI. By univariate analysis, both measures of reperfusion success strongly correlate with survival and assessment of both yields incremental prognostic information beyond either measure alone. By multivariable analysis, however, SigmaSTR is the stronger prognostic variable.     

Myocardial blush grade: a predictor for major adverse cardiac events after primary PTCA with stent implantation for acute myocardial infarction

OBJECTIVES: Optimal myocardial reperfusion is of great importance for survival of patients with AMI undergoing PTCA. According to the Thrombolysis In Myocardial Infarction (TIMI) 3 score, restoration of epicardial flow is achieved in the majority of patients. However, the myocardial blush grade (MBG) may offer additional information for survival. Therefore, we sought to determine whether myocardial blush grades were associated with MACE during follow-up in a high-risk AMI population undergoing primary PTCA with stent implantation. METHODS: Hundred-and-thirty patients with AMI underwent PTCA with stent implantation from 1999 to 2004. The clinical, angiographic and follow-up data were extracted from the hospital records. Apart from the availability and technical adequacy of the angiograms for angiographic analysis, there were no exclusion criteria. RESULTS: Post-procedural TIMI 3 flow was achieved in 103 (79%) patients, while MBG-3 was observed in only 44 (34%) patients. Less post-intervention AMI, cardiac deaths or any MACE occurred in patients with MBG 3 (4/44) compared with MBG 1 or 2 (36/86) (P < 0.01). MBG 3 was a strong predictor of absence of MACE during 5-year follow-up (P < 0.01), whereas no association was found between TIMI 3 and event-free survival (P > 0.5) in our population. CONCLUSION: Our data show that (1) MBG 3 is an important marker for survival and (2) the predictive value of MBG is superior to the TIMI flow grades. Given the predictive validity of MBG shown for MACE-free survival and low rate of MBG 3 despite achievement of TIMI 3 flow, a prospective study with adjunctive therapies to enhance myocardial perfusion is warranted.     

Impaired coronary flow reserve immediately after coronary angioplasty in patients with acute myocardial infarction.

OBJECTIVE--To examine coronary flow reserve immediately after emergency coronary angioplasty in patients with acute myocardial infarction. DESIGN--A 3 F coronary Doppler catheter was used to measure coronary blood flow velocity in the infarct artery and in the non-infarct artery. Maximal hyperaemia was produced by 10 mg of intracoronary papaverine and coronary flow reserve was calculated. PATIENTS--11 patients with acute myocardial infarction undergoing both emergency coronary angioplasty (4.7 (3.6) h after the onset of chest pain (mean (SD))) and at follow up catheterisation 16 (4) days after angioplasty. SETTING--Hiroshima City Hospital. RESULTS--There was no stenosis of > or = 50% in the coronary artery of interest. Immediately after coronary angioplasty the mean (1 SD) coronary flow reserve of the infarct artery was significantly less than that of the non-infarct artery (1.4 (0.4) v 2.8 (0.8), p < 0.001). At follow up catheterisation the coronary flow reserve of the infarct artery increased almost to the value of the non-infarct artery (2.8 (1.2) v 3.1 (0.8) p = NS). CONCLUSION--The coronary flow reserve in the infarct region was severely impaired immediately after reperfusion, even with a widely patent infarct artery. This could restrict the beneficial effects of reperfusion therapy, especially when there is a severe residual stenosis.