Effects of glucose-insulin-potassium infusion on ST-elevation myocardial infarction in patients treated with thrombolytic therapy

The role of glucose-insulin-potassium (GIK) infusion in the management of acute myocardial infarction is not well established. This prospective, randomized study comprised 120 patients who had ST-elevation myocardial infarction that was treated within 12 hours from symptom onset with a high dose of GIK (25% glucose, 50 IU of soluble insulin per liter, and 80 mmol of potassium chloride per liter at 1 ml/kg/hour over 24 hours) as adjunct to thrombolytic therapy (1.5 MU of streptokinase/30 to 60 minutes; GIK group) or thrombolytic therapy alone (control group). The primary end point of the study was the rate of major adverse cardiac events (MACEs) at 1 month, defined as a composite of cardiac death, reinfarction, serious arrhythmias (ventricular fibrillation and/or tachycardia), and severe heart failure. The secondary end points were the rate of MACEs at 1 year and improvement in left ventricular systolic function. The incidence of MACEs at 1 month was significantly lower in the GIK group (10% vs 32.5%, relative risk 0.24, 95% confidence interval 0.09 to 0.63, p = 0.0043). Patients in the GIK group had significant decreases in ventricular tachycardia and/or fibrillation (1.3% vs 15.0%, p = 0.003) and severe heart failure (3% vs 12.5%, p = 0.031). The rate of MACEs at 1 year was also significantly lower in the GIK group (13% vs 40.0%, relative risk 0.22, 95% confidence interval 0.09 to 0.55, p = 0.0012). After 1 year, there was a significant improvement in left ventricular ejection fraction in the GIK group (from 48 +/- 8% to 51 +/- 10%, p <0.01), which was not observed in the control group. In conclusion, high-dose GIK, used as an adjunct to thrombolytic therapy, was safe and improved clinical outcome at 1 month. The beneficial effect of GIK infusion was maintained up to 1 year.     

Impact of myocardial perfusion on left atrial remodeling following primary angioplasty for acute myocardial infarction

OBJECTIVES: To investigate the impact of myocardial perfusion on left atrial remodeling and its determinants after primary percutaneous coronary intervention for acute myocardial infarction. BACKGROUND: Left atrial volume is an important predictor of morbidity and mortality in acute myocardial infarction, while thrombolysis in myocardial infarction (TIMI) myocardial perfusion (TMP) grade is an angiographic index associated with infarct size and mortality. As yet, however, the relationship between TMP grade and left atrial remodeling has not been investigated. METHODS: Conventional transthoracic echocardiography was performed in 105 patients (55+/-13 years old, 92 men) with acute myocardial infarction within 24 h and after 6 months (mean 9+/-4, range 6-29 months) following successful primary percutaneous coronary intervention. Absolute left atrial volume was calculated using an elliptical model. Myocardial perfusion was evaluated, using TMP grade, by visual assessment on the coronary angiogram. Patients were divided into three groups on the basis of myocardial perfusion status, as TMP 0/1 (n=36), TMP 2 (n=36) and TMP 3 (n=33). RESULTS: No difference was observed between baseline and follow-up left atrial volumes in the overall study population (42.5+/-16.1 vs. 43.5+/-17.4 ml, P=0.519). As regards TMP grade, follow-up left atrial volume significantly increased in the TMP 0/1 group (43+/-17 vs. 54.6+/-1.1 ml, P<0.001) and significantly decreased in the TMP 3 group (42.9+/-15.7 vs. 35.5+/-12.2 ml, P=0.001) compared with initial values. No change was observed in left atrial volume in the TMP 2 group. Multivariate analysis showed that TMP grade (P<0.001) and anterior location of myocardial infarction (P<0.001) were independent determinants of left atrial remodeling. CONCLUSIONS: These results suggest that poor myocardial perfusion and anterior location of myocardial infarction can affect left atrial remodeling in patients with acute myocardial infarction undergoing primary percutaneous coronary intervention. It appears that adequate myocardial perfusion is crucial to prevent left atrial remodeling, a poor prognostic factor in acute myocardial infarction.     

Frequency of left ventricular free-wall rupture in patients with acute myocardial infarction treated with primary angioplasty

A total of 590 patients with myocardial infarction treated with primary angioplasty were studied, to assess the incidence and related factors of free-wall rupture in patients with acute myocardial infarction when treated with primary angioplasty. The incidence of free-wall rupture was 2.2% (13 patients); this incidence was higher in patients >65 years old, women, nonsmokers, as well as in those with anterior location and an initial TIMI grade 0 flow, but it was similar in patients with a successful or unsuccessful angiographic result.     

Enhancement of left ventricular function by glucose-insulin-potassium infusion in acute myocardial infarction

Twenty-eight patients admitted to the hospital with suspected acute myocardial infarction underwent baseline studies within 12 hours of onset of symptoms. Patients were then randomized to receive control infusion (0.45 percent sodium chloride at 20 ml/hour) (15 patients) or glucoseinsulin-potassium infusion (300 g glucose, 50 units regular insulin, 80 mEq KCl/liter water at 1.5 ml/kg per hour) (13 patients) for 48 hours. All patients received 0.45 percent sodium chloride for 2 more days. Coronary arteriograms and left ventriculograms were obtained in 26 (93 percent) of 28 patients 2 to 3 weeks after infarction.Radionuclide ejection fraction improved during glucose-insulin-potassium infusion (49 ± 4 to 55 ± 5 percent, p < 0.01). Before discharge, the angiographic ejection fraction was greater in the glucose-insulin-potassium recipients than in control patients (43 ± 3 versus 35 ± 3 percent, p < 0.05). Radionuclide ejection fraction decreased in all control patients during the study (42 ± 4 to 37 ± 3 percent, p < 0.0005) and did not change significantly in the treated group (49 ± 4 to 43 ± 5 percent, p = not significant [NS] by paired t test). Regional wall motion analysis revealed an increase in ejection fraction in the “infarcted zone” in the treated group only (44 ± 7 to 54 ± 8 percent, p < 0.01) during glucose-insulin-potassium infusion. There was also a significant decrease in ejection fraction in the “noninfarcted zone” in the control group only (50 ± 4 to 45 ± 4 percent, p < 0.01).During experimental infusion pulmonary arterial end-diastolic pressure decreased in the glucose-insulin-potassium group (17 ± 2 to 12 ± 2 mm Hg, p < 0.01) without changing significantly in the control group. Calculated end-diastolic and end-systolic volume indexes changed in opposite directions in the two groups during experimental infusion (end-diastolic volume index 80 ± 5 to 90 ± 9 ml/m² in the control group versus 70 ± 9 to 55 ± 6 ml/m² in the treated group, p < 0.005 for change from baseline value between groups and the end-systolic volume index 48 ± 6 to 55 ± 8 ml/m² in the control group versus 39 ± 8 to 26 ± 5 ml/m² in the treated group (p < 0.01 for change from baseline value between groups).These data suggest that glucose-insulin-potassium infusion after acute myocardial infarction in human beings (1) increases global ejection fraction, (2) Increases ejection fraction in the “infarcted zone” without changing ejection fraction in the “noninfarcted zone”, and (3) decreases pulmonary arterial end-diastolic pressure and end-diastolic and end-systolic volumes.     

急诊或延迟PTCA对急性心肌梗死患者心功能的影响

目的　探讨急诊经皮腔内冠状动脉成形术 (PTCA) (<6h)与延迟 PTCA对急性心肌梗死近期左心室重构及功能的影响。方法　选择本院住院的急性心肌梗死病人 5 8例 ,按发病到达医院时间的不同随机分为两组 ,6h以内为 A组共 2 2例行急诊 PTCA,6h以后 3 6例为 B组行延迟 PTCA。于术后 3 d、3 0 d、90 d行二维超声心动图检查。结果　 A组男 18例 ,女 4例 ,平均年龄 5 8.65±8.94岁。 B组男 2 9例 ,女 7例 ,平均年龄 5 7.2 3± 11.3 6岁 ,发病至 PTCA时间为 8.4± 3 .6d。两组实施 PTCA后血管再通率均为10 0 %。术后 3 d、3 0 d及 90 d,A组左心室舒张末期容积指数 (EDVI)、收缩末期容积指数 (ESVI)和左心室射血分数 (L VEF)均显著优于 B组 (P<0 .0 5 ,P<0 .0 5 ,P<0 .0 5 )。 A组左心室功能于 3 0 d明显改善 ,EDVI及 ESVI均显著缩小 (P<0 .0 5 ,P<0 .0 5 ,P<0 .0 5 ) ;90 d时左心室功能、EDVI、ESVI仍有改善 ,但与 3 0 d比无显著差异。 B组左心室功能、EDVI、ESVI 3 0 d与术后 3 d比较有所改善但无显著性差异 ;90 d与 3 d比较 ,EDVI、ESVI显著改善 (P<0 .0 5 ,P<0 .0 5 ) ,左心室功能有所改善但无显著性差异。结论　急诊 PTCA能挽救濒死心肌、抑制左心室重构、改善左心室功能 ,其效果优于延迟 PTCA;延迟 PTCA虽不?     

Glucose-insulin-potassium infusion inpatients treated with primary angioplasty for acute myocardial infarction: the glucose-insulin-potassium study: a randomized trial

OBJECTIVES: In this study we considered the question of whether adjunction of glucose-insulin-potassium (GIK) infusion to primary coronary transluminal angioplasty (PTCA) is effective in patients with an acute myocardial infarction (MI). BACKGROUND: A combined treatment of early and sustained reperfusion of the infarct-related coronary artery and the metabolic modulation with GIK infusion has been proposed to protect the ischemic myocardium. METHODS: From April 1998 to September 2001, 940 patients with an acute MI and eligible for PTCA were randomly assigned, by open-label, to either a continuous GIK infusion for 8 to 12 h or no infusion. RESULTS: The 30-day mortality was 23 of 476 patients (4.8%) receiving GIK compared with 27 of 464 patients (5.8%) in the control group (relative risk [RR] 0.82, 95% confidence interval [CI] 0.46 to 1.46). In 856 patients (91.1%) without signs of heart failure (HF) (Killip class 1), 30-day mortality was 5 of 426 patients (1.2%) in the GIK group versus 18 of 430 patients (4.2%) in the control group (RR 0.28, 95% CI 0.1 to 0.75). In 84 patients (8.9%) with signs of HF (Killip class > or =2), 30-day mortality was 18 of 50 patients (36%) in the GIK group versus 9 of 34 patients (26.5%) in the control group (RR 1.44, 95% CI 0.65 to 3.22). CONCLUSIONS: Glucose-insulin-potassium infusion as adjunctive therapy to PTCA in acute MI did not result in a significant mortality reduction in all patients. In the subgroup of 856 patients without signs of HF, a significant reduction was seen. The effect of GIK infusion in patients with signs of HF (Killip class > or =2) at admission is uncertain.     

Relation of terminal QRS distortion to left ventricular functional recovery and remodeling in acute myocardial infarction treated with primary angioplasty

The association between admission electrocardiogram and 6-month change in left ventricular function and volume was assessed in 200 patients who had acute myocardial infarction that was treated with primary percutaneous coronary intervention. Logistic regression analysis indicated peak creatine phosphokinase-MB, number of Q-wave leads, QRS interval distortion, wall motion score index, and angiographic Thrombolysis In Myocardial Infarction flow grade as predictors of no functional recovery and QRS interval distortion and Thrombolysis In Myocardial Infarction flow grade as predictors of left ventricular remodeling.     

Clinical outcomes and left ventricular function in diabetic patients with acute myocardial infarction treated by primary coronary angioplasty

The objective of the present study was to compare left ventricular (LV) function and clinical outcomes in diabetics versus nondiabetics with acute myocardial infarction (AMI) treated by primary coronary angioplasty. A total of 327 consecutive AMI subjects were reperfused by primary coronary angioplasty within 12 hours from onset. Diabetes mellitus (DM) was present in 104 of the 327 patients. LV function was serially determined by left ventriculograms taken in the acute and chronic phases (6 months after onset). (I) The early ST-segment resolution rate was lower in DM patients compared with non-DM patients (59% versus 83%, P < 0.0001). (II) During a 6-month follow-up, the percentages of target vessel revascularization (TVR), coronary aorta bypass grafting (CABG), and cardiac death were higher in the DM patients compared with the non-DM patients (TVR: 29% versus 19%; P < 0.05, CABG: 10% versus 5% ; P < 0.05, cardiac death: 12% versus 4%; P = 0.01). (III) The differences in left ventricular ejection fraction (LVEF) between two stages (delta-LVEF) were significantly lower in the DM patients than the non-DM patients (1 +/- 9% versus 7 +/- 10%, P < 0.0001). (IV) Multivariate analysis identified DM as an independent predictor of cardiac death (Odds ratio 5.5, 95% CI, 1.3-23.7, P < 0.05) and as a sole independent predictor of LVEF deterioration (Odds ratio 5.8, 95% CI, 2.8-11.8, P < 0.001). In patients with AMI treated using primary coronary angioplasty, DM is closely related to left-ventricular systolic dysfunction and a poor patient outcome, including mortality.     

Comparison of left ventricular ejection fraction and inducible ventricular tachycardia in ST-elevation myocardial infarction treated by primary angioplasty versus thrombolysis

Electrophysiologic studies predict the risk for sudden death after myocardial infarction (MI). Although primary angioplasty has become the preferred method of treatment for ST-elevation MI, intravenous thrombolysis remains the first-line treatment in 30% to 70% of cases worldwide. Rates of ventricular tachyarrhythmias may vary according to type of reperfusion treatment. This study was undertaken to examine the hypothesis that the left ventricular ejection fraction (LVEF) and rates of inducible ventricular tachycardia may be more favorable in treatment with primary angioplasty rather than thrombolysis. Consecutive patients receiving primary angioplasty (n = 225) or thrombolysis (n = 195) for ST-elevation MI were included. The mean LVEF was 48 +/- 12% for the primary angioplasty group and 46 +/- 13% for the thrombolysis group (p = 0.30). The proportion of patients with LVEFs <40% was 30% in the primary angioplasty group and 30% in the thrombolysis group (p = 0.98). Patients with LVEFs <40% underwent electrophysiologic studies. Ventricular tachycardia was inducible in 23 of 66 primary angioplasty patients (34.8%) compared with 21 of 55 (38.1%) thrombolysis patients (p = 0.69). Implantable cardiac defibrillators were inserted in 30 patients, of whom 8 (27%) had appropriate device activations. The mean time from MI to first spontaneous activation was 387 +/- 458 days. In conclusion, patients treated with thrombolysis or primary angioplasty for ST-elevation MIs had similar resultant LVEFs and rates of inducible ventricular tachycardia. There was a surprisingly high rate of spontaneous defibrillator activations, often occurring late after MI.     

Influence of treatment delay on long-term left ventricular function in patients with acute myocardial infarction successfully treated with primary angioplasty

BACKGROUND: Myocardial salvage has been shown to be dependent on the time elapsed from the onset of acute myocardial infarction (AMI) to reperfusion. The aim of this study was to evaluate the importance of time to reperfusion for left ventricular function recovery after primary angioplasty (percutaneous transluminal coronary angioplasty [PTCA]) for AMI. METHODS: Ninety-five patients undergoing long-term successful PTCA for AMI were studied. Echocardiography was performed before and 3, 7, 30, 90, and 180 days after PTCA. End-diastolic volume index (EDVI) and end-systolic volume index (ESVI), ejection fraction, and left ventricular wall motion score index (WMSI) were evaluated. RESULTS: Patients were divided into group A, 23 patients reperfused within 2 hours; group B, 32 patients reperfused between 2 and 4 hours; group C, 22 patients reperfused between 4 and 6 hours; and group D, 18 patients reperfused between 6 and 12 hours. Both EDVI and ESVI were reduced in groups A and B at 90 days. Groups C and D did not show any changes of EDVI and ESVI at any stage throughout the study. Ejection fraction improved only in groups A and B at 30, 90, and 180 days. At study entry, WMSI was similar in all groups. After 7 days, in group A and in group B, WMSI was improved, no changes were observed in group C, and a mild deterioration was observed in group D at 3 and 7 days. Subsequent evaluations showed progressive improvement of WMSI in all groups. CONCLUSIONS: Myocardial salvage is achieved only in patients revascularized within 4 hours from AMI onset. However, revascularization after 6 hours may be worthwhile by preventing ventricular remodeling.     

再灌注心律失常对急性心肌梗死患者心肌细胞凋亡和左室重构的影响

目的探讨急性心肌梗死（AMI）患者再灌注心律失常（RA）、心肌细胞凋亡和左室功能的关系。方法156例经急诊再灌注治疗的AMI患者,分为RA组58例（24小时内出现RA）,非再灌注心律失常（Non．RA）组98例。应用ELISA方法,分别检测再灌注治疗成功后即刻、7天和2—4周血清细胞凋亡信号分子Fas／APO-1水平,并在1周、6个月和1年做心脏彩超,检测左室射血分数（LVEF）和左室舒张末期内径（LVEDD）。结果（1）RA组血管开通时间较Non-RA组晚,且前降支病变较Non-RA组发生率高（P〈0．05）。（2）再灌注治疗成功后即刻,RA组血清Fas／APO-1浓度明显高于Non-RA组[（13．82±4．36）μg/L与（8．19±3．56）μg/L,P〈0．05]。（3）再灌注治疗成功后第7天,两组患者血清Fas／APO-1浓度达高峰,2—4周时明显下降,与第7天比较差异有统计学意义[RA组（10．91±3．65）μg/L与（14．26±4．98）μg/L,P〈0．05;Non-RA组（4．69±1．87）μg/L与（12．19±3．25）μg/L,P〈0．01],且2—4周时RA组Fas／APO-1浓度明显高于Non．RA组[（10．91±3．65）μg/L与（4．69±1．87）μg/L,P〈0．01]。（4）AMI再灌注治疗成功后1周,RA组与Non-RA组比较,LVEF和LVEDD差异无统计学意义[LVEF（47．7±9．6）％与（49．2±8．9）％,P〉0．05;LVEDD（59．7±10．3）mm与（57．4±12．4）mm,P〉0．05]。（5）AMI再灌注治疗成功1年后,Non-RA组LVEF明显高于自身急性期和RA组[分别为（59．5±9．2）％、（49．2±8．9）％和（49．9±10．1）％,P〈0．05],LVEDD虽然无显著性变化（P〉0．05）,但有增加趋势。结论心肌缺血严重患者易发生RA,且与心肌缺血所诱发心肌细胞凋亡有关,影响左室功能的恢复,促进心室重构。     

Effect of impaired myocardial reperfusion on left ventricular remodeling in patients with anterior wall acute myocardial infarction treated with primary coronary intervention

We assessed the effect of impaired myocardial blush after primary coronary intervention (PCI) on left ventricular remodeling in patients with ST-segment elevation myocardial infarction (STEMI). The study population consisted of 145 patients with first anterior STEMI that was treated successfully (Thrombolysis In Myocardial Infarction grade 3 flow) with PCI. Left ventricular remodeling was defined as an increase of > or =20% in end-diastolic volume based on repeated echocardiographic measurements in patients. The study population was divided into 2 groups according to the presence (myocardial blush grade [MBG] 2 to 3, n = 86) or absence (MBG 0 to 1, n = 59) of myocardial reperfusion. Left ventricular remodeling appeared in 21% of the entire study group. Poor myocardial blush after PCI was associated with an increased rate of remodeling compared with good myocardial reperfusion (32% vs 14%, hazard ratio 2.308, 95% confidence interval [CI] 1.21 to 4.39, p=0.014). Symptoms of heart failure were observed significantly more often in patients with MBG 0 to 1 (35.6% vs 18.6%, p = 0.032) than in patients with MBG 2 to 3. In multivariate analysis, only age (odds ratio 0.96, 95% CI 0.92 to 0.99, p = 0.02) and MBG 0 to 1 (odds ratio 3.15, 95% CI 1.35 to 7.31, p = 0.008) were associated with left ventricular dilation. In conclusion, impaired microvascular reperfusion is associated with left ventricular remodeling and development of congestive heart failure in patients with anterior STEMI that is treated with primary coronary angioplasty.     

Dynamics of left ventricular remodeling in patients with acute myocardial infarction

Dynamics of structural and functional left ventricular parameters was investigated in 51 patients with acute anterior myocardial infarction by means of serial (on days 1, 2, 3, 5, 7, 10 and 21 of infarction) echocardiographical study. Increase of end-diastolic volume index relative to initial values became significant on 5th-7th days and continued to progress until 3rd week of infarction. Left ventricular cavity became dilated and attained more occurred shape predominantly at the account of increased transverse diameters. Abnormalities of left ventricular contractile and pump functions were most pronounced during first 3 days of the disease. Between 5th and 10th days improvement and stabilization of myocardial functional state took place accompanied by progression of left ventricular dilation and increase of its sphericity with lessening of degree of myocardial asynergy.     

Predictors of left ventricular thrombus formation in acute myocardial infarction treated with successful primary angioplasty with stenting

BACKGROUND: There are limited data referring to the incidence of left ventricle (LV) thrombus formation after successful primary percutaneous coronary intervention (PCI) with stenting, which is now the treatment of choice in patients with acute myocardial infarction (AMI). Previously reported results were often based on low or heterogeneous patient populations. METHODS: To evaluate the prevalence of LV thrombus in the early period of AMI, 2,911 patients who had undergone successful primary stenting were retrospectively studied. Baseline demographic characteristics, angiographic findings, and antiplatelet treatment were analyzed to find predictors of thrombus formation. LV thrombus was diagnosed by 2-dimensional echocardiography within 3 to 5 days after PCI. RESULTS: This complication was detected in 73 patients (2.5%). Patients with thrombus and patients without it were at the same age and had diabetes mellitus, prior myocardial infarction, and lipid disorders at the same frequency. The extent of coronary artery disease was similar in both groups. The incidence of LV thrombi was similar in patients treated with and without glycoprotein IIb/IIIa inhibitors (2.02% vs 2.9%, NS). According to results of multiple log-regression analysis, the presence of LV thrombus was strongly associated with anterior AMI, ejection fraction <40%, and previous hypertension. CONCLUSIONS: The incidence of left ventricular thrombus early after AMI is very low if primary PCI with stenting is successful, probably due to the salvage of myocardium at risk. Localization of AMI and the size of myocardium damage remain the most important independent predictors of LV thrombus formation irrespective of various treatments.     

AMI患者PCI后心肌灌注水平对心功能及左室重构的影响

目的:探讨急性心肌梗死（AMI）患者经皮冠脉介入术（PCI）后TIMI血流III级时的心肌灌注水平及其对心功能与左室重构的影响。方法: 对36例AMI患者PCI后行经静脉心肌声学造影（MCE）和心脏二维超声检查。①利用心肌声学造影评分（MCS）及室壁运动评分(WMS)分析PCI后心肌灌注情况与室壁运动情况的关系;②根据声学造影积分指数（CSI）将患者分为A、B两组,比较两组的左室射血分数（LVEF）,评估心肌灌注水平对心功能的影响;③根据心脏二维超声结果,比较两组患者术后6个月时左室舒张末直径（LVEDD）及LVEF的变化,进一步评估心肌灌注水平对左室重构的影响。结果: PCI后梗死相关血管TIMI血流均达III级。共152节段与梗死相关血管的再灌注有关。①MCS为0分的18节段中,2个（11.1%）WMS为1~2分;MCS为0.5分的30节段中16个（53.3 %）WMS为1~2分;MCS为1分的104节段中,82个（78.8%）WMS为1~2分;统计学分析显示,PCI后心肌灌注水平与室壁运动呈正相关（P<0.05）。②心肌灌注好的A组LVEF显著大于B组［(52.1±3.4)%,(47.2±2.9)%,P<0.05］。③术后6个月A组的LVEF及LVEDD均无明显变化,B组的LVEF较前有所下降［(47.2±2.9)%,(43.8±4.4)%,P<0.05］,LVEDD较前有所增加［(50.2±2.9) mm,(56.3±3.1) mm,P<0.05］。结论: AMI患者PCI后心肌灌注水平与心功能及左室重构有一定相关性,良好的心肌灌注在一定程度上可以抑制左室重构。     

Evaluation of myocardial perfusion and deformation in patients with acute myocardial infarction treated with primary angioplasty and stent placement

PURPOSE: To prospectively compare the usefulness of myocardial perfusion and deformation imaging for the prediction of functional recovery and left ventricular (LV) remodeling in patients with ST-elevation myocardial infarction (STEMI). METHODS: We prospectively examined 36 patients with reperfused STEMI, 12+ or -9 h after primary angioplasty and stent placement. LV function was reevaluated at 4-6 months of follow-up, to assess relative improvement of LV-ejection fraction (DeltaEF%) and increase in end-diastolic volume (DeltaEDV). RESULTS: During the follow-up period, 19 of 36 patients showed LV function improvement (DeltaEF%> or =10%), whereas 10 patients had LV remodeling (DeltaEDV> or =20%). Peak negative strain (epislon (peak)), peak negative strain rate (SRpeak), and myocardial blood flow (Axbeta) correlated with DeltaEF% (r=-0.55, -0.57, and 0.46, respectively, P<0.01 for all), and allowed for prediction of LV remodeling on an individual level (area under the curve of 0.85 for strain rate, 0.95 for strain, and 0.90 for regional blood flow, P<0.001 for all). The combined assessment of myocardial perfusion and deformation correctly predicted LV remodeling in four additional patients, compared with each technique separately. CONCLUSION: Contrast echocardiography, strain Doppler imaging, and possibly the combination of both are useful for the prediction of adverse LV remodeling and for the early risk stratification of patients with STEMI.     

重组人脑利钠肽对大鼠心肌梗死后心室重构及功能的影响

目的 探讨重组人脑利钠肽(rhBNP)对心肌梗死后大鼠心室重构及心功能的影响.方法 建立急性心肌梗死(AMI)雄性SD大鼠模型45只,随机分为AMI对照组、小剂量rhBNP治疗组、大剂最rhBNP治疗组,每组各15只.另设15只作假手术组.rhBNP治疗组经颈静脉输液管输注rhBNP,剂量分别为5μg/ks和15 μg/kg,1次/d,持续4周,假手术组及AMI对照组仅以等体积的生理盐水输注.4周后检测血液动力学及心功能参数,心脏标本检测左室重量及左室重量指数(LVMI)、心肌梗死面积,并检测血浆和心肌血管紧张素Ⅱ(Ang Ⅱ)水平.结果 AMI对照组左室重量、LVMI及心肌AngⅡ水平明显高于假手术组,而收缩压及左室内压最大上升和下降速率(±dp/dt)均明显低于假手术组(均P<0.01).大、小剂量rhBNP治疗组左室重量及LVMI、心肌梗死面积和心肌AngⅡ水平均明显低于AMI对照组[左室重量:分别为(492.6±34.0)mg、(498.8±47.8)mg比(570.0±24.2)mg,P<0.01;LVMI:2.0±0.2、2 0±0.2比2.3±0.1,P<0.01;心肌梗死面积:(25.3±2.9)%、(31.4±3.0)%比(46.4±3.0)%,P<0.01;Ang Ⅱ水平:(881.3±62.7)pg/L、(1186.0±94.5)pg/L比(2436.7±280.3)pg/L,P<0.05],收缩压和±dp/dt也高于AMI对照组(P<0.01或P<0.05).结论 外源性的rhBNP连续应用能限制梗死面积、减轻AMI后心室重构、保护心功能.     

Markers of myocardial reperfusion as predictors of left ventricular function recovery in acute myocardial infarction treated with primary angioplasty

BACKGROUND: Myocardial blush grade (MBG), corrected TIMI frame count (cTFC), and ST-segment reduction are indices of myocardial reperfusion. HYPOTHESIS: We evaluated their predictive value for left ventricular (LV) function recovery by gated single-photon emission computed tomography (SPECT) after acute myocardial infarction (AMI) treated with primary percutaneous coronary intervention (PCI). METHODS: In 40 patients with AMI, gated SPECT was performed at admission and repeated 7 and 30 days after PCI. Left ventricular function recovery was defined as an increase > or = 10 points in SPECT LV ejection fraction from baseline to 1 month. The MBG, cTFC, and ST-segment elevation index 1 h after PCI were determined to evaluate reperfusion. RESULTS: Twenty-four patients (Group 1) had LV function recovery and 16 (Group 2) did not. A significant correlation was found between LV function recovery and MBG (r = 0.66; p = 0.0001), and ST-segment elevation index at 1 h (r = -0.55; p = 0.0001), but not with cTFC. Univariate predictors of LV function recovery were MBG (p = 0.0003) and ST-segment elevation index 1 h after intervention (p = 0.0026), but not cTFC. In a multivariate analysis, MBG was the only predictor of LV function recovery. Myocardial blush grade > or = 2 and ST-segment elevation index reduction had the same accuracy (88%) for predicting LV function recovery. Lower accuracy (75%) was shown by fast cTFC (< 23 frames). Myocardial blush grade > or = 2 showed the better negative likelihood ratio, and ST-segment elevation index reduction had the higher positive likelihood ratio in predicting LV function recovery. CONCLUSIONS: Myocardial blush grade was the best parameter for prediction of LV function recovery: MBG > or = 2 and ST-segment elevation index reduction showed good accuracy in predicting LV function recovery. The cTFC failed to be a significant predictor.