High-risk subgroups of patients with non-Q wave myocardial infarction based on direction and severity of ST segment deviation

To determine the significance of the direction of ST segment deviation on admission of patients who evolved non-Q wave myocardial infarction (MI), 97 patients with initial ST segment depression were compared to 207 patients with initial ST segment elevation. Patients with ST segment depression developed smaller infarcts than those with ST segment elevation (creatine kinase MB isoenzyme 8.2 vs 13.3 gmEq/m2, p less than 0.002), but had a lower left ventricular ejection fraction on admission (44% vs 51%, p less than 0.001), more in-hospital complications, and a higher cumulative 1-year mortality (29% vs 11%, p less than 0.001) that could be accounted for by an excess of adverse baseline characteristics. Although a severity index (combining magnitude and extent of the initial ST segment deviation) was not useful for discriminating prognosis of patients with non-Q wave MI who presented with ST segment depression, it was useful in identifying a subgroup of patients with ST segment elevation with an adverse prognosis. The poor outcome of patients with non-Q wave MI presenting with either ST segment depression or severe ST segment elevation on admission suggests that patients in these subgroups should receive close surveillance and should possibly be considered for aggressive therapy.     

Prognostic significance of ST segment depression in lateral leads I, aVL, V5 and V6 on the admission electrocardiogram in patients with a first acute myocardial infarction without ST segment elevation

OBJECTIVESWe sought to investigate the short-term prognostic value of the admission electrocardiogram (ECG) in patients with a first acute myocardial infarction (MI) without ST segment elevation.BACKGROUNDST segment depression on hospital admission predicts a worse outcome in patients with a first acute MI, but the prognostic information provided by the location of ST segment depression remains unclear.METHODSIn 432 patients with a first acute MI without Q waves or ≥0.1 mV of ST segment elevation, we evaluated the ability of the initial ECG to predict in-hospital death.RESULTSThe presence, magnitude and extent of ST segment depression were associated with an increased mortality, but the only electrocardiographic variable that was significant in predicting death after adjusting for baseline predictors was ST segment depression in two or more lateral (I, aVL, V₅, or V₆) leads (odds ratio 3.5, 95% confidence interval 1.2 to 10.6). Patients with lateral ST segment depression (n = 91, 21%) had higher rates of death (14.3% vs. 2.6%, p < 0.001), severe heart failure (14.3% vs. 4.1%, p < 0.001) and angina with electrocardiographic changes (20.0% vs. 11.6%, p = 0.04) than did the remaining patients, even though they had similar peak creatine kinase, MB fraction levels (129 ± 96 vs. 122 ± 92 IU/liter, p = NS). In contrast, ST segment depression not involving the lateral leads did not predict a poor outcome. Among patients who were catheterized, those with lateral ST segment depression had a lower left ventricular ejection fraction (57 ± 12% vs. 66 ± 13%, p = 0.001) and more frequent left main coronary artery or three-vessel disease than did the remaining patients (60% vs. 22%, p < 0.001).CONCLUSIONSIn patients with a first non–ST segment elevation acute MI, ST segment depression in the lateral leads on hospital admission predicts a poor in-hospital outcome.     

Prognostic significance of ST segment depression in lateral leads I, aVL, V5 and V6 on the admission electrocardiogram in patients with a first acute myocardial infarction without ST segment elevation

OBJECTIVES

We sought to investigate the short-term prognostic value of the admission electrocardiogram (ECG) in patients with a first acute myocardial infarction (MI) without ST segment elevation.

BACKGROUND

ST segment depression on hospital admission predicts a worse outcome in patients with a first acute MI, but the prognostic information provided by the location of ST segment depression remains unclear.

METHODS

In 432 patients with a first acute MI without Q waves or ≥0.1 mV of ST segment elevation, we evaluated the ability of the initial ECG to predict in-hospital death.

RESULTS

The presence, magnitude and extent of ST segment depression were associated with an increased mortality, but the only electrocardiographic variable that was significant in predicting death after adjusting for baseline predictors was ST segment depression in two or more lateral (I, aVL, V₅, or V₆) leads (odds ratio 3.5, 95% confidence interval 1.2 to 10.6). Patients with lateral ST segment depression (n = 91, 21%) had higher rates of death (14.3% vs. 2.6%, p < 0.001), severe heart failure (14.3% vs. 4.1%, p < 0.001) and angina with electrocardiographic changes (20.0% vs. 11.6%, p = 0.04) than did the remaining patients, even though they had similar peak creatine kinase, MB fraction levels (129 ± 96 vs. 122 ± 92 IU/liter, p = NS). In contrast, ST segment depression not involving the lateral leads did not predict a poor outcome. Among patients who were catheterized, those with lateral ST segment depression had a lower left ventricular ejection fraction (57 ± 12% vs. 66 ± 13%, p = 0.001) and more frequent left main coronary artery or three-vessel disease than did the remaining patients (60% vs. 22%, p < 0.001).

CONCLUSIONS

In patients with a first non–ST segment elevation acute MI, ST segment depression in the lateral leads on hospital admission predicts a poor in-hospital outcome.     

Clinical Characteristics and Prevalence of Early Repolarization Associated With Ventricular Arrhythmias Following Acute ST-Elevation Myocardial Infarction

Early repolarization (ER) on a 12-lead electrocardiogram has recently been associated with ventricular tachyarrhythmias (VTAs) in patients without structural heart disease and in patients with healed myocardial infarction (MI). An association between ER and VTAs in the setting of acute ST-segment elevation MI (STEMI) has not been explored. In a single-center retrospective case-control design, 50 patients with STEMI complicated by VTAs (cases), defined as ventricular fibrillation, sustained ventricular tachycardia, or nonsustained ventricular tachycardia within 72 hours of the index hospitalization, were matched for age and gender with 50 subjects with STEMI without VTAs (controls). Electrocardiograms obtained an average of 1 year before STEMI were analyzed for ER pattern, defined as notching or slurring of the terminal QRS complex or J-point elevation >0.1 mV above baseline in ≥2 contiguous leads. A higher prevalence of ER was associated with VTAs overall in cases compared to controls (26% vs 4%, p = 0.01) and localized to anterior (16% vs 0%) and inferior (14% vs 2%, p = 0.07) leads but not lateral limb leads. Notching (10% vs 2%, p = 0.1) and J-point elevation (16% vs 0%) were more common in cases. Slurring was uncommon. ER was associated with VTAs (odds ratio [OR] 6.5, 95% confidence interval [CI] 1.5 to 28.8, p = 0.01), even after adjustment for creatine kinase-MB (OR 9.2, 95% CI 1.6 to 53.4, p = 0.01) and ejection fraction (OR 5.7, 95% CI 1.2 to 27.1, p = 0.03). In conclusion, ER is associated with VTAs in patients with STEMI even after adjustment for left ventricular ejection fraction or creatine kinas-MB levels. Larger prospective studies exploring potential associations and mechanisms of ventricular arrhythmogenesis with ER pattern are needed.     

Long-term, cause-specific mortality after myocardial infarction in diabetes.

AIMS: To compare long-term, cause-specific mortality after reperfusion therapy for ST segment elevation myocardial infarction (STEMI) in patients with and without diabetes. METHODS AND RESULTS: Patients with STEMI (n = 395) were randomised to intravenous streptokinase (SK) or primary percutaneous coronary intervention (PCI). Median follow-up was 7.5 years (interquartile range 5.6-8.5). A total of 74 patients (19%) had diabetes. Reduced left ventricular ejection fraction (<40%) after STEMI was more often observed in patients with diabetes (27% vs. 15%, P = 0.02). Patients with diabetes had a higher total mortality compared to patients without diabetes (HR 2.4; P < 0.001). Multivariate analysis confirmed that diabetes was an independent risk factor for long-term mortality (HR 2.3; P < 0.001). The incidence of sudden death was comparable in both patient groups (HR 1.6; P = 0.23). The increased mortality in patients with diabetes was mainly caused by heart failure (HR 3.1; P = 0.004). In patients with diabetes, primary PCI was associated with an improved prognosis. CONCLUSIONS: Despite reperfusion therapy, STEMI patients with diabetes have an increased long-term mortality. This is due to death by heart failure and not by an increase in sudden death. Primary PCI is associated with an improved prognosis, particularly in patients with diabetes.     

Atrial fibrillation during myocardial infarction with and without ST segment elevation

INTRODUCTION: The occurrence of atrial fibrillation (AF) in the acute phase of myocardial infarction with ST segment elevation is common and responsible for an excess hospital mortality. The aim of this work was to define the incidence, predictive factors, and the prognostic impact of AF during MI with and without raised ST segment in the RICO study. PATIENTS AND METHODS: Between January 2001 and July 2003, 1701 patients were included in this study: 130 (7.6%) had AF in the first 24 hours of management (AF+ group); 1571 (92.4%) remained in sinus rhythm (AF- group). RESULTS: Among the 1701 patients included in this study, 1197 (70.4%) had MI with raised ST and 504 (29.6%) had MI without raised ST. The incidence of AF was identical whatever the type of MI (7.6% with raised ST versus 7.7% without, p=0.334). The presence of Killip class >2 on admission and chronic obstructive pulmonary disease were independent predictive factors for the occurrence of AF (OR=3.84, p=0.007, and OR=2.47, p=0.014 respectively). The presence of AF was significantly associated with the occurrence of ventricular arrhythmia and/or cardiovascular mortality during admission in the non-selected MI population whatever the type of MI (raised ST ; AF+; 34% and AF-; 18%, p<0.01 versus without raised ST; AF+; 36% and AF-; 16%, p = 0.01). CONCLUSION: This study provides evidence that the incidence of AF during the first 24 hours of MI, as well as its poor prognosis, are identical whether or not there is ST segment elevation.     

New ECG criteria for high-risk Brugada syndrome.

To identify high-risk patients with Brugada syndrome, the present study reviewed 60 standard 12-lead electrocardiograms from 60 patients collected by the Japanese Brugada syndrome registry. Under blinded conditions, the S wave of lead V(1) was measured from the tip of r to r', and the amplitude of the ST segment in lead V(2) was measured at 0.08 s from the J point. In patients with ventricular fibrillation (n=17), the S wave was significantly longer in V(1) (0.085+/-0.007 s vs 0.075+/-0.011 s, p=0.001), and ST segment elevation in V(2) was significantly greater (0.323+/-0.133 mV vs 0.236+/-0.129 mV, p=0.012) than in patients without fibrillation. An S wave width of 0.08 s or more in V(1) had a positive predictive value of 40.5% and negative predictive value of 100% for ventricular fibrillation, with 100% sensitivity. ST elevation of 0.18 mV or more in V(2) had a positive predictive value of 37.8% and a negative predictive value of 100% for ventricular fibrillation, with 100% sensitivity. Both an S wave width > or =0.08 s in V(1) and ST elevation > or =0.18 mV in V(2) were highly specific indicators of ventricular fibrillation and are proposed as new criteria for high-risk Brugada syndrome.     

Resolution of ST-segment elevation after streptokinase therapy in anterior versus inferior wall myocardial infarction

BACKGROUND: Resolution of ST-segment elevation is the best bedside predictor of myocardial reperfusion. HYPOTHESIS: This study was conducted to examine the resolution of ST-segment elevation after streptokinase therapy in anterior versus inferior acute myocardial infarction (MI) and to corroborate it with echocardiographic and coronary angiographic data. METHODS: The study population consisted of 70 patients, 35 each in the anterior and inferior MI groups. The electrocardiograms (ECGs) were recorded before, on completion of, and on Days 1 and 2 post streptokinase therapy. The resolution of ST segment determined from post-streptokinase ECGs was compared between the two groups and correlated with echocardiographic and coronary angiographic data. RESULTS: On completion of and on Day 1 post streptokinase therapy, ST-segment resolution in both groups was not significantly different. On Day 2 post streptokinase therapy, resolution of the ST segment per lead was significantly lower in anterior than that in inferior MI (61 +/- 21% anterior vs. 77 +/- 21% inferior, p 0.003). The number of patients with akinesis of infarct-related ventricular wall was significantly higher (17 anterior vs. 7 inferior, p 0.02), and left ventricular ejection fraction was significantly lower in anterior MI (39 +/- 7% anterior vs. 48 +/- 8% inferior, p < 0.01). There was no significant difference in coronary angiographic data. One patient in each group demonstrated normal coronary arteries. CONCLUSIONS: The resolution of ST-segment elevation on the completion of and on Day 1 post streptokinase therapy was comparable between anterior and inferior MI. The significantly less frequent resolution of ST-segment elevation in anterior MI on Day 2 post streptokinase could be due to more akinesis, larger infarct size, and worse systolic function rather than due to failure to open the infarct-related vessel.     

Relationship between changes in ST segment elevation and patency of the infarct-related coronary artery in acute myocardial infarction

Forty-one patients with acute myocardial infarction and ST segment elevation were studied to determine the relationship between early changes in ST segment elevation, time to peak serum creatine kinase (CK), peak serum CK, left ventricular function, and patency of the infarct-related artery. ST segment elevation decreased by more than 40% within 8 hours of peak sigma ST in all patients with inferior infarction and in 10 of the 13 patients with anterior infarction and subtotal occlusion, but in none of the patients with anterior infarction and total occlusion (p = 0.003). The time to peak serum CK was related to the rate of decrease of ST segment elevation in patients with anterior (r = 0.59) and inferior (r = 0.71) infarction. In patients with anterior infarction, peak serum CK tended to be lower and left ventricular ejection fraction (EF) higher in those with rapid resolution of ST segment elevation than in those with persistent ST elevation (1721 +/- 1422 U/L vs 3285 +/- 1148 U/L, p less than 0.10, for peak CK; and 50.3 +/- 18.5% vs 41.2 +/- 12.8%, p = NS, for EF), but there was no difference in the patients with inferior infarction. Early resolution of ST segment elevation is an index of early spontaneous antegrade or collateral reperfusion in patients with acute myocardial infarction.     

Myocardial infarction as a presentation of clinical in-stent restenosis.

BACKGROUND: In-stent restenosis is considered to be a gradual and progressive condition and there is scant data on myocardial infarction (MI) as a clinical presentation. METHODS AND RESULTS: Of 2,462 consecutive patients who underwent percutaneous coronary intervention between June 2001 and December 2002, clinical in-stent restenosis occurred in 212 (8.6%), who were classified into 3 groups: ST elevation MI (STEMI), non-ST elevation MI (NSTEMI) and non-MI. Of the 212 patients presenting with clinical in-stent restenosis, 22 (10.4%) had MI (creatine kinase (CK)>or=2xbaseline with elevated CKMB). The remaining 190 (89.6%) patients had stable angina or evidence of ischemia by stress test without elevation of cardiac enzymes. Median interval between previous intervention and presentation for clinical in-stent restenosis was shorter for patients with MI than for non-MI patients (STEMI, 90 days; NSTEMI, 79 days; non-MI, 125 days; p=0.07). Diffuse in-stent restenosis was more frequent in MI patients than in non-MI patients (72.7% vs 56.3%; p<0.005). Renal failure was more prevalent in patients with MI than in those without MI (31.8% vs 6.3%, p=0.001). Compared with the non-MI group, patients with MI were more likely to have acute coronary syndromes at the time of index procedure (81.8% vs 56.8%, p=0.02). CONCLUSION: Clinical in-stent restenosis can frequently present as MI and such patients are more likely to have an aggressive angiographic pattern of restenosis. Renal failure and acute coronary syndromes at the initial procedure are associated with MI.     

Impact of the magnitude of the initial ST-segment elevation on left ventricular function in patients with anterior acute myocardial infarction.

BACKGROUND: In the percutaneous coronary intervention (PCI) era, the impact of initial ST-segment elevation magnitude on left ventricular (LV) function in patients with acute myocardial infarction (AMI) remains unclear. METHODS AND RESULTS: In the present study, 239 patients with total occlusion and 81 patients with spontaneous reperfusion within 12 h of their first anterior AMI were evaluated. The sum of ST-segment elevation (SigmaST) was measured in leads I, aV(L) and V(1-6) shortly before angiography. Predischarge LV ejection fraction (LVEF) was obtained at 15+/-5 days. In total occlusion, the predischarge LVEF was significantly lower in patients with SigmaST >/=10 mm than in those with SigmaST <10 mm (51+/-14% vs 57+/-14%, p<0.01). However, in spontaneous reperfusion, there was no significant difference between patients with ST >/=10 mm and those with SigmaST <10 mm (61+/-13 vs 62+/-14 %, p=NS). Predischarge LVEF significantly correlated with SigmaST in total occlusion (r=-0.25, p<0.01), but not in spontaneous reperfusion (r=0.03, p=NS). CONCLUSION: The results suggest that initial SigmaST is an important predictor of LV function in patients with total occlusion, but not in those with spontaneous reperfusion.     

Role of myocardial ischemia in the genesis of stress-induced S-T segment elevation in previous anterior myocardial infarction

This study tests the hypothesis that myocardial ischemia is responsible for exercise-induced S-T segment elevation in patients with previous anterior myocardial infarction (MI). Exercise stress testing in conjunction with thallium imaging of the myocardium was performed in 28 patients with previously documented anterior MI. Thallium images were analyzed by computer for the presence of initial uptake defects and evidence of abnormal clearance of the isotope from the myocardium (that is, imaging evidence of ischemia). Total S-T segment elevation (∑ST) in precordial leads V₁ to V₆ at rest was subtracted from ∑ST at peak stress in order to quantitate the extent of S-T elevation induced by stress (ΔST). Two groups of patients were identified; 1 with stress-induced S-T elevation (Group I, ΔST ≥ 4.0 mm) and 1 without this abnormality (Group II, ΔST < 4.0 mm). Evidence of abnormal thallium washout from myocardial scan segments occurred in 12 of 15 Group I patients versus 9 of 13 Group II patients (difference not significant). In addition, abnormal tracer washout from anterolateral or septal scan segments occurred in 5 patients in each group. Likewise, abnormal thallium clearance from inferior or posterior scan segments occurred in 8 of 15 Group I patients versus 7 of 13 Group II patients (difference not significant). The patient with the greatest amount of stress-induced S-T elevation (S-T 11.5 mm) had no evidence of ischemia during the stress test. However, Group I patients did have larger anterolateral plus septal initial thallium uptake defect scores than did those of Group II (10 of 15 with defect score ≥ 350 in Group I versus 1 of 13 in Group II, p <0.002). Similarly, resting left ventricular ejection fraction ≥ 30% was present in only 4 of 15 Group I patients versus 13 of 13 in Group II (p <0.001). Finally, multiple stepwise linear regression analysis demonstrated that ΔST correlated best with the extent of initial anterolateral plus septal thallium uptake defect score (F = 17.3, p < 0.001) and to a lesser extent with resting ejection fraction (F = 5.2, p < 0.05) and change in heart rate from rest to peak stress (F = 8.1, p < 0.01; corrected multiple correlation coefficient = 0.76, p < 0.001). Thus, in patients with previous anterior MI (1) exercise-induced myocardial ischemia occurs as often with as without S-T segment elevation, (2) myocardial ischemia is not required for the production of stress-induced S-T segment elevation, and (3) stress-induced S-T elevation primarily reflects the extent of previous anterior wall damage and to a lesser extent an increase in heart rate between rest and peak stress.     

Comparative early and late outcomes after primary percutaneous coronary intervention in ST-segment elevation and non-ST-segment elevation acute myocardial infarction (from the CADILLAC trial)

We determined the outcomes of patients with acute ST-segment elevation (STE) myocardial infarction (STEMI) and non-STEMI (NSTEMI) after primary percutaneous coronary intervention (PCI). The prognosis after primary PCI in STEMI has been extensively studied and defined. Outcomes of patients who undergo primary PCI for NSTEMI are less well established. In total, 2,082 patients with ongoing chest pain for > 30 minutes consistent with acute MI were randomized to balloon angioplasty versus stenting, each with/without abciximab. Of 1,964 patients, STEMI was present in 1,725 (87.8%) and NSTEMI in 239 (12.2%). Compared with STEMI, those with NSTEMI were more likely to have delayed time-to-hospital arrival (2.4 vs 1.8 hours, p = 0.0002) and increased door-to-balloon time (3.2 vs 1.9 hours, p < 0.0001). Patients with NSTEMI were more likely to have Thrombolysis In Myocardial Infarction grade 3 flow at baseline (37.3% vs 19.4%, p < 0.0001) and higher ejection fraction (58.7% vs 55.8%, p = 0.001), but similar rates of postprocedural Thrombolysis In Myocardial Infarction grade 3 flow. At 1 year, patients with NTEMI had similar mortality (3.4% vs 4.4%, p = 0.40) but higher rates of major adverse cardiac events (24.0% vs 16.6%, p = 0.007) that was driven by more frequent ischemic target vessel revascularization (21.8% vs 11.9%, p <0.0001). In conclusion, patients with acute MI without STE who are treated with primary PCI have marked delays to treatment, similar late mortality, and increased rates of ischemic target vessel revascularization compared with patients with STEMI, despite more favorable angiographic features at presentation and similar reperfusion success. The adverse prognosis of patients with NSTEMI should be recognized and efforts made to decrease reperfusion times.     

Percutaneous thrombectomy with the RESCUE system in acute myocardial infarction

BACKGROUND: Percutaneous coronary interventions (PCI) in acute myocardial infarction with ST segment elevation (STEMI) are associated with distal coronary embolisation. It may be speculated that percutaneous thrombectomy preceding stent implantation may prevent coronary microcirculation from embolisation. AIM: To assess safety and efficacy of percutaneous thrombectomy in patients with STEMI. METHODS: Seventy two patients with STEMI were randomised to PCI with stent implantation alone (n=32) or percutaneous thrombectomy with the RESCUE system, followed by stent implantation (n=40). Coronary flow in infarct related artery before and after the procedure was assessed using TIMI scale and corrected TIMI frame count - cTFC. Myocardial blood flow was measured using TIMI myocardial perfusion grade - tMPG. The degree of ST segment resolution 60 min after PCI was also assessed. Left ventricular ejection fraction (LVEF) was measured in hospital and three months later. RESULTS: The two groups did not differ with respect to the time from the onset of symptoms to the procedure (236+/-162 min vs 258+/-198 min, NS) or the baseline TIMI, cTFC and tMPG values. An effective thrombectomy procedure was performed in 35 (87%) patients from group B. After the procedure, the number of patients with TIMI 3 grade as well as cTFC values and the proportion of patients with tMPG 3 were similar in both groups (86% vs 85%, NS; 19 vs 21, NS; and 38% vs 54%, NS). The sum of ST segment elevations after the procedure was significantly greater in patients who underwent PCI only compared with patients who had thrombectomy and PCI (6.8+/-5.2 mm vs 3.6+/-2.9 mm, p=0.004). Complete normalisation of ST segment was achieved in 68% of patients treated with thrombectomy and PCI compared with 25% of patients who had PCI only (p=0.005). CK-MB peak values occurred significantly earlier in patients treated with thrombectomy (92.1% vs 66.7% up to 360 min, p=0.01). After 3 months of follow-up, LVEF tended to be greater in patients treated with thrombectomy and PCI than in those who underwent PCI only (55.3+/-14.7% vs 60.3+/-9.2%, NS). CONCLUSIONS: Thrombectomy with the RESCUE system in patients with STEMI is safe and effectively restores patency of infarct related artery. Thrombectomy better improves myocardial perfusion than standard PCI.     

The PREHAMI (PREsillion™ in high‐risk acute myocardial infarction) registry

Objectives : To evaluate the efficacy of the new Cobalt–Chromium (Co‐Cr) Presillion? stent for the treatment of high‐risk acute myocardial infarction (MI) patients. Background : Percutaneous coronary intervention (PCI) with stent represents the gold standard treatment for acute MI. Methods and Results : We enrolled patients with high‐risk acute MI (either ST‐segment elevation MI or non‐ST‐segment elevation MI) treated with PCI using a new Co‐Cr bare metal stent with closed cells design and limited balloon compliance. We considered high‐risk features as one of the following: age ≥70 years, ejection fraction ≤35%, glomerular filtration rate ≤60 mL/min, diabetes mellitus, rescue PCI, or chronic atrial fibrillation or other conditions requiring long‐term oral anticoagulation therapy. Primary outcome of the study was rate of major adverse cardiac events (MACE) defined as all‐cause death, new MI, and target‐vessel revascularization. A total of 129 consecutive patients were enrolled (69 ± 11 years, 74% men): 71 (55%) patients with ST‐segment elevation MI and 58 (45%) patients with non‐ST‐segment elevation MI. A total of 153 vessels (169 lesions and 179 stents) were treated. The device success rate was high (98.8%). In‐hospital MACE rate was 5.4% mainly because of death associated with the acute MI. At 1‐year follow‐up, the MACE rate was 17.3%, with 11% all‐cause death (7.9% of cardiac origin), 0.6% of stent thrombosis, and 4.6% target‐vessel revascularization. Conclusions : The use of the Co‐Cr Presillion stent in patients with high‐risk acute MI treated invasively seems to be safe and efficacious with optimal deliverability and good long‐term outcomes and represents a good option in the treatment of these patients. © 2011 Wiley‐Liss, Inc.     

抽吸导管在急性ST段抬高型心肌梗死直接经皮冠脉介入治疗中的疗效观察

目的评价抽吸导管在急性ST段抬高型心肌梗死（STEMI）直接经皮冠脉介入治疗（PCI）中的疗效。方法随机入选行急诊PCI的急性STEMI患者80例,其中使用抽吸导管后行支架置人术32例（抽吸导管组）,未使用抽吸导管而行球囊扩张及支架置人术48例（直接PCI组）。观察两组术后即刻TIMI血流分级、无复流现象、术后即刻胸痛缓解率、术后1hST段回落≥50％（STR≥50％）发生率和心梗后24h及2周左室舒张末径（LVDD）、左室射血分数（LVEF）。结果抽吸导管组即刻TIMI血流2-3级高于直接PCI组（94％比75％,P〈0．05）,抽吸导管组无复流现象低于直接PCI组;抽吸导管组术后1hSTR≥50％、胸痛缓解率均高于急诊PCI组（94％比71％、88％比71％,均P〈0．05）;抽吸导管组心梗后24hLVDD低于直接PCI组[（54．2±4．1）mm比（56．2±4．2）mm,P〈0．05],心梗后24hLVEF高于直接PCI组[（57．6＋5．24）％比（55．0±4．6）％,P〈0．05],梗后2周LVDD及LVEF两组间差异无统计学意义。结论急诊PCI时联合使用抽吸导管可减少无复流发生,改善心肌再灌注及心肌梗死早期心功能。     

Diagnostic Value of Exercise‐Induced ST‐Segment Elevation in Q‐Wave Leads. After Recent Myocardial Infarction

Background: Exercise‐induced ST‐segment elevation in an infarct territory with abnormal Q waves is a known marker for more severe left ventricular wall‐motion abnormalities. However, it is reported, that exercise‐induced ST‐segment elevation in infarct leads may indicate residual viability in the intarctregion. The aim of the study was to test whether exercise‐induced ST‐segment elevation is related to left ventricular (LV) dysfunction or to persistent viability in patients with previous myocardial infarction (MI). Methods: 145 consecutive patients (119 men, 26 women, age 58 ± 11 years) 2–3 weeks after Q‐wave Ml but without ST elevation at rest ECG were enrolled in the study. All patients underwent a target heart rate or symptom‐limited exercise testing (ET) with Bruce protocol. Exercise‐induced ST‐segment elevation < 1 mm above the baseline ST segment level (80 ms after J point) in more than 1 ECG lead with Q wave was considered to be significant. Patients were divided in two groups according to ET results: group I, 25 patients with significant exercise‐induced ST‐segment elevation and group II, 120 patients without exercise‐induced ST‐segment elevation. All patients underwent rest ECHO and low dose dobutamine stress echo (LOSE) within 7 days after ET. LV function was estimated using ejection fraction (EF). Results: More severe LV dysfunction was observed in patients from group 1 (EF 31 ± 8.16% vs EF 45 ± 10.3%). Myocardial viability (defined as an improvement of regional systolic wall thickening in the regions with resting regional wall‐motion abnormalities during LOSE 5 to 15 g/kg/min was recognized in 8 patients (32%) in group I and 31 patients (25.8%) in group II. There was no relation between exercise‐induced ST‐segment elevation and myocardial viability (chi‐square test: 2,809; NS). Conclusions: Exercise‐induced ST‐segment elevation in most cases is associated with left ventricular dysfunction. Patients with exercise‐induced ST‐segment elevation have a lower EF than those without and greater severity of resting wall‐motion abnormalities. Our results suggest that exercise‐induced ST‐segment elevation is not related to residual myocardial viability.     

墓碑形ST段抬高对心肌梗死范围及近期预后的影响

目的　探讨心电图墓碑形 ST段抬高对心肌梗死范围及预后的影响。方法　根据心电图 ST段抬高形式 ,将170例急性 ST段抬高型心肌梗死患者分为墓碑形组 5 2例 ,非墓碑形组 118例 ,比较两组心电图 ST段抬高振幅、QRS记分、血清肌酸激酶 (CK )及其同工酶 (CK - MB)峰值 ,并对其 4周内心脏事件进行分析。结果　墓碑形组 ST段抬高的振幅、QRS记分、CK和 CK- MB峰值均显著高于非墓碑形组 (P<0 .0 1)。墓碑形组心源性休克、心力衰竭、心室颤动和病死率分别为 11.5 4 %、4 2 .31%、2 6 .92 %和 19.2 3%,均高于非墓碑形组 2 .5 4 %、2 4 .5 8%、12 .71%和6 .78%(P<0 .0 5 )。 L ogistic回归分析结果显示 ,墓碑形 ST段抬高与心源性休克、心力衰竭、心室颤动和死亡危险独立相关 (OR分别为 1.880、1.5 73、2 .2 75和 3.0 6 4 ;均 P<0 .0 5 )。结论　墓碑形 ST段抬高提示心肌梗死范围大 ,是预后不良的独立预测指标。     

Assessment of the first myocardial infarctions with lead ECG --implications in the study of hospital mortality and its reduction using thrombolytic drugs

STUDY OBJECTIVE: Correlation between mortality reduction of first Myocardial Infarction (MI) by thrombolytic therapy and MI size evaluated with the classical Electrocardiogram (ECG). DESIGN: A retrospective sequential study. SETTING: Coronary Unit patients. PATIENTS: Sequential sample of 132 patients with first MI obeying all the following criteria: 1) no previous MI; 2) age less than or equal to 70 years; 3) clinical evolution less than 12 hours; 4) no Left Bundle Branch Block in the CCU first ECG; 5) ischemic ST elevation in greater than or equal to 1 initial ECG leads. Patients were divided into Group A, with less than or equal to 3 initial ECG leads with ischemic ST elevation (n = 80), and Group B, with greater than or equal to 4 initial ECG leads with ischemic ST elevation (n = 52). Only 34 patients (25.7%) did thrombolytic therapy with IV Streptokinase (SK); 15 from Group A and 19 from Group B. MEASUREMENTS AND MAIN RESULTS: 17 patients died in MI acute phase (12.8%); 4 in Group A (5%) and 13 in Group B (24.9%). Inhospital mortality was statistically worst in Group B than in Group A (24.9% vs 5% with p less than 0.01). Creatin kinase (CK) maximal values (A = 911.5 UI; B = 1444.6 UI with p less than 0.01) and initial Heart Rate (A = 75.7; B = 86.7 with p less than 0.001) were also statistically greatest in Group B. Inhospital mortality was smaller in patients treated with SK (8.8% vs 14.3%), as in Group B (10.5% vs. 33.3%), both without statistical significance. CONCLUSIONS: Inhospital mortality and thrombolytic therapy benefit were so bigger as MI size evaluated by the number of initial ECG leads with ischemic ST elevation, by initial HR and maximal values of CK. Classical ECG can be useful by identifying patients with first MI that can more benefit with thrombolytic therapy (greater than or equal to 4 leads with ischemic ST elevation).     

临床路径对ST段抬高心肌梗死患者再灌注治疗疗效的影响

目的评价临床路径对急性ST段抬高心肌梗死患者就诊至球囊扩张时间、梗死心肌的再灌注治疗疗效的影响。方法随机选择100例实施急性ST段抬高心肌梗死急诊冠状动脉介入术临床路径的患者作为试验组,同时随机选择100例同期未实施临床路径的急性ST段抬高心肌梗死急诊冠状动脉介入术的住院患者为对照组。主要观察指标是就诊至球囊扩张时间、90 min目标时间内完成球囊扩张的比例、术中心肌梗死介入治疗后3级血流获得率及术后90 min ST段回落的比例、肌酸激酶同工酶酶峰值、住院病死率。结果试验组就诊至球囊扩张时间显著短于对照组(中位数,65 min比95 min,P<0.001),就诊90 min内完成球囊扩张的比例显著高于对照组(98%比65%,P<0.001)。临床路径显著提高术中心肌梗死介入治疗3级血流获得率(94%比81%,P<0.05)及术后90 min ST段回落>50%的比例(88%比67%,P<0.05),肌酸激酶同工酶酶峰值也明显提前(7.8±0.5比10.1±0.4,P<0.05),试验组住院病死率显著低于对照组(2%比7%,P<0.001)。结论临床路径可显著缩短就诊至球囊扩张时间,增加了90 min目标时间内完成球囊扩张的比例,能够更好地改善梗死区域心肌的微循环,显著提高梗死心肌的再灌注治疗疗效,这一作用对于降低住院病死率也具有非常显著的帮助,证实了临床路径管理是一种新的行之有效的服务管理模式。