Stenting of the Infarct-Related Artery During Complicated Angioplasty in Acute Myocardial Infarction

The aim of this study was to assess safety and efficacy of coronary stenting as a strategy for improving PTCA suboptimal angiographic result. From March 1993 to December 1995, 104 patients underwent PTCA during acute myocardial infarction. Unplanned coronary stenting was required in 66 pts (63.5%). Procedural success was obtained in 64 pts (97%). Two patients had an unsuccessful stenting procedure: one patient for a suboptimal stent deployment and another for LAD reocclusion requiring emergency CABG (1.5%). Palmaz-Schatz stents were used in 60 pts (91%) and AVE micro-stent in 6 pts (9%). During the hospital course, subacute reocclusion of the vessel occurred in 3 pts (4.6%); one patient underwent a successful rePTCA while the other two underwent CABG. Two patients had vascular groin complications requiring surgical repair of the femoral artery. During hospitalization, one patient underwent elective CABG for early residual myocardial ischemia. At seventy-two hours from PTCA, one patient (1.5%) died as a result of intestinal infarct. Six months survival rate was 98.3% for 59 pts discharged alive from our department. Ten pts were symptomatic during the follow-up: One patient underwent PTCA on another vessel and the other underwent CABG for a multivessel disease. CABG was used in one patient who presented residual silent ischemia in multivessel coronary artery disease. At six months, the first group of patients (18 pts) underwent planned coronary angiography: Vessel patency was present in 17 patients. One patient had an asymptomatic reocclusion of the treated vessel. This study shows a good angiographic result obtained with intracoronary stenting during primary or rescue PTCA of the infarct-related artery. It does not appear to increase major in-hospital adverse events and may reduce the need for surgical revascularization, reducing in-hospital mortality rate and favorably affecting LVEF.     

Randomized Comparison of Primary Coronary Angioplasty With Thrombolytic Therapy in Low Risk Patients With Acute Myocardial Infarction

Objectives. We sought to compare primary coronary angioplasty and thrombolysis as treatment for low risk patients with an acute myocardial infarction.Background. Primary coronary angioplasty is the most effective reperfusion therapy for patients with acute myocardial infarction; however, intravenous thrombolysis is easier to apply, more widely available and possibly more appropriate in low risk patients.Methods. We stratified 240 patients with acute myocardial infarction at admission according to risk. Low risk patients (n = 95) were randomized to primary angioplasty or thrombolytic therapy. The primary end point was death, nonfatal stroke or reinfarction during 6 months of follow-up. Left ventricular ejection fraction and medical charges were secondary end points. High risk patients (n = 145) were treated with primary angioplasty.Results. In low risk patients, the incidence of the primary clinical end point (4% vs. 20%, p < 0.02) was lower in the group with primary coronary angioplasty than in the group with thrombolysis, because of a higher rate of reinfarction in the latter group. Mortality and stroke rates were low in both treatment groups. There were no differences in left ventricular ejection fraction or total medical charges. High risk patients had a 14% incidence rate of the primary clinical end point.Conclusions. Simple clinical data can be used to risk-stratify patients during the initial admission for myocardial infarction. Even in low risk patients, primary coronary angioplasty results in a better clinical outcome at 6 months than does thrombolysis and does not increase total medical charges.(J Am Coll Cardiol 1997;29:908–12)© 1997 by the American College of Cardiology     

Recovery of Myocardial Perfusion in Acute Myocardial Infarction After Successful Balloon Angioplasty and Stent Placement in the Infarct-Related Coronary Artery

Objectives. This study sought to investigate changes in myocardial perfusion after direct percutaneous transluminal coronary angioplasty (PTCA) in acute myocardial infarction (MI).Background. After initially successful recanalization of the infarct-related artery, coronary perfusion may deteriorate as a result of reocclusion, distal embolization of platelet aggregates formed at the dilated plaque or microvascular reperfusion injury. This change could offset the benefit from early intervention.Methods. The study included 19 patients in whom the infarct-related artery was successfully recanalized by PTCA with Palmaz-Schatz stent placement within 24 h after the onset of pain. Basal and papaverine-induced coronary blood flow were assessed by Doppler flow velocity measurements and quantitative coronary angiography. In addition, basal and adenosine-induced myocardial blood flow were measured by nitrogen-13 ammonia positron emission tomography (PET).Results. Immediately after completion of the intervention, the average coronary flow reserve (CR) in the recanalized vessel was 1.56 ± 0.51; it increased to 2.04 ± 0.65 at 1 h (p = 0.013) and to 2.66 ± 0.72 at 2 weeks after reperfusion (p = 0.008, n = 16). PET studies in 12 patients revealed that perfusion defect size and CR in the infarct region (2.19 ± 0.89 vs. 2.33 ± 0.86) did not change significantly between day 2 after recanalization and 2 weeks. However, we found significant (p < 0.03) increases in basal (by 26%) and adenosine-induced (by 40%) blood flow in the infarct region.Conclusions. Despite the persistence of a perfusion defect after successful recanalization of the occluded artery in acute MI, CR of the infarct region improves in most patients within 1 h and further improves within 2 weeks.     

Clinical Experience With Primary Percutaneous Transluminal Coronary Angioplasty Compared With Alteplase (Recombinant Tissue-Type Plasminogen Activator) in Patients With Acute Myocardial Infarction : A Report From the Second National Registry of Myocardial Infarction (NRMI-2)

Objectives. We sought to compare outcomes after primary percutaneous transluminal coronary angioplasty (PTCA) or thrombolytic therapy for acute myocardial infarction (MI).Background. Primary PTCA and thrombolytic therapy are alternative means of achieving reperfusion in patients with acute MI. The Second National Registry of Myocardial Infarction (NRMI-2) offers an opportunity to study the clinical experience with these modalities in a large patient group.Methods. Data from NRMI-2 were reviewed.Results. From June 1, 1994 through October 31, 1995, 4,939 nontransfer patients underwent primary PTCA within 12 h of symptom onset, and 24,705 patients received alteplase (recombinant tissue-type plasminogen activator [rt-PA]). When lytic-ineligible patients and patients presenting in cardiogenic shock were excluded, baseline characteristics were similar. The median time from presentation to initiation of rt-PA in the thrombolytic group was 42 min; the median time to first balloon inflation in the primary PTCA group was 111 min (p < 0.0001). In-hospital mortality was higher in patients in shock after rt-PA than after PTCA (52% vs. 32%, p < 0.0001). In-hospital mortality was the same in lytic-eligible patients not in shock: 5.4% after rt-PA and 5.2% after PTCA. The stroke rate was higher after lytic therapy (1.6% vs. 0.7% after PTCA, p < 0.0001), but the combined end point of death and nonfatal stroke was not significantly different between the two groups (6.2% after rt-PA and 5.6% after PTCA). There was no difference in the rate of reinfarction (2.9% after rt-PA and 2.5% after PTCA).Conclusions. These findings suggest that in lytic-eligible patients not in shock, PTCA and rt-PA are comparable alternative methods of reperfusion when analyzed in terms of in-hospital mortality, mortality plus nonfatal stroke and reinfarction.     

替罗非班对急性ST段抬高型心肌梗死患者急诊经皮冠状动脉介入治疗术后心肌生化标志物及临床预后的影响

目的前瞻性评价替罗非班对急性ST段抬高型心肌梗死(STEMI)患者急诊经皮冠状动脉介入治疗(PCI)术后肌酸激酶混合型同工酶、肌钙蛋白I、酶性心肌梗死面积以及主要心脏不良事件(MACE)发生率的影响.方法183例接受急诊PCI治疗的STEMI患者,随机分为替罗非班组(92例)和对照组(91例).比较两组基础临床情况、介入治疗结果、急诊PCI术前和术后血清肌酸激酶混合型同工酶、肌钙蛋白I、酶性心肌梗死面积、住院期和术后180天左心室射血分数及MACE发生率.结果替罗非班组与对照组相比,基础临床情况、介入治疗结果及术前肌酸激酶混合型同工酶、肌钙蛋白I水平差异均不具有统计学意义(P＞0.05).替罗非班组与对照组相比,急诊PCI术后肌酸激酶混合型同工酶峰值(P＜0.01)和肌酸激酶混合型同工酶均值(P＜0.01)、肌钙蛋白I峰值(P=0.01)和肌钙蛋白I均值(P＜0.05)、酶性心肌梗死面积(P＜0.05)均显著降低,差异均具有统计学意义.替罗非班组与对照组相比,住院期及术后180天左心室射血分数(P＜0.05～0.01)明显增加,MACE发生率(P＜0.05)显著降低,差异均具有统计学意义.多因素回归分析表明,替罗非班治疗是降低STEMI患者急诊PCI术后180天MACE发生率的独立决定因素(OR=0.39,P＜0.01).替罗非班组术后出血并发症发生率高于对照组,但差异不具有统计学意义(P＞0.05).结论替罗非班能显著降低STEMI患者急诊PCI.术后肌酸激酶混合型同工酶、肌钙蛋白I峰值和均值,明显缩小酶性心肌梗死面积,并显著改善住院期及术后180天临床预后.     

Myocardial Contrast Echocardiography Versus Dobutamine Echocardiography for Predicting Functional Recovery After Acute Myocardial Infarction Treated With Primary Coronary Angioplasty

Objectives. We sought to compare myocardial contrast echocardiography with low dose dobutamine echocardiography for predicting 1-month recovery of ventricular function in acute myocardial infarction treated with primary coronary angioplasty.

Background. The relation between myocardial perfusion and contractile reserve in patients with acute myocardial infarction, in whom anterograde flow is fully restored without significant residual stenosis, is still unclear.

Methods. Thirty patients with acute myocardial infarction treated successfully with primary coronary angioplasty underwent intracoronary contrast echocardiography before and after angioplasty and dobutamine echocardiography 3 days after the index infarction. One month later, two-dimensional echocardiography and coronary angiography were repeated in all patients and contrast echocardiography in 18 patients.

Results. After coronary recanalization, 26 patients showed myocardial reperfusion within the risk area, although 4 did not. At 1-month follow-up, all patients had a patent infarct-related artery without significant restenosis. Both left ventricular ejection fraction and wall motion score index within the risk area significantly improved in the patients with reperfusion ([mean ± SD] 38 ± 8% vs. 48 ± 12%, p < 0.005; and 2.35 ± 0.5 vs. 2 ± 0.6, p < 0.001, respectively), but not in those with no reflow. Of the 72 nonperfused segments before angioplasty, 27 showed functional improvement at follow-up. Myocardial contrast echocardiography had a sensitivity and a negative predictive value similar to dobutamine echocardiography in predicting late functional recovery (96% vs. 89% and 89% vs. 93%, respectively), but a lower specificity (18% vs. 91%, p < 0.001), positive predictive value (41% vs. 86%, p < 0.001) and overall accuracy (47% vs. 90%, p < 0.001).

Conclusions. Microvascular integrity is a prerequisite for myocardial viability after acute myocardial infarction. However, contrast enhancement shortly after recanalization does not necessarily imply a late functional improvement. Thus, contractile reserve elicited by low dose dobutamine is a more accurate predictor of regional functional recovery after reperfused acute myocardial infarction than microvascular integrity.

(J Am Coll Cardiol 1996;28:1677–83)>     

Left Main Coronary Artery Thrombosis With Acute Myocardial Infarction: A Management Dilemma

Left main coronary artery (LMCA) thrombosis with acute myocardial infarction is a rare condition with very high mortality. The low incidence of this condition and exclusion of patients with LMCA thrombosis from clinical trials prevent the development of optimal management strategy in these patients. Therefore, there are no clear-cut guidelines describing an evidence-based approach for this condition. We describe a patient with LMCA thrombosis presenting with acute myocardial infarction, who was found to have hypercoagulable state related to homocysteinemia on further work-up. This case highlights the challenges faced during the management of this rare condition due to lack of clear-cut guidelines describing an evidence-based approach.     

A Prospective, Randomized Evaluation of Prophylactic Intraaortic Balloon Counterpulsation in High Risk Patients With Acute Myocardial Infarction Treated With Primary Angioplasty

Objectives. A large, international, multicenter, prospective, randomized trial was performed to determine the role of prophylactic intraaortic balloon pump (IABP) counterpulsation after primary percutaneous transluminal coronary angioplasty (PTCA) in acute myocardial infarction (AMI).

Background. Previous studies have suggested that routine IABP use after primary PTCA reduces infarct-related artery reocclusion, augments myocardial recovery and improves clinical outcomes.

Methods. Cardiac catheterization was performed in 1,100 patients within 12 h of onset of AMI at 34 clinical centers. Clinical and angiographic variables were used to stratify patients undergoing primary PTCA into high and low risk groups. High risk patients were then randomized to 36 to 48 h of IABP (n = 211) or traditional care (n = 226). The study had 80% power to detect a reduction in the primary end point from 30% to 20%.

Results. There was no significant difference in the predefined primary combined end point of death, reinfarction, infarct-related artery reocclusion, stroke or new-onset heart failure or sustained hypotension in patients treated with an IABP versus those treated conservatively (28.9% vs. 29.2%, p = 0.95). The IABP strategy conferred modest benefits in reduction of recurrent ischemia (13.3% vs. 19.6%, p = 0.08) and subsequent unscheduled repeat catheterization (7.6% vs. 13.3%, p = 0.05) but did not reduce the rate of infarct-related artery reocclusion (6.7% vs. 5.5%, p = 0.64), reinfarction (6.2% vs. 8.0%, p = 0.46) or mortality (4.3% vs. 3.1%) and was associated with a higher incidence of stroke (2.4% vs. 0%, p = 0.03). IABP use did not result in enhanced myocardial recovery as assessed by paired admission to predischarge and 6-week rest and exercise left ventricular ejection fraction.

Conclusions. In contrast to previous studies, a prophylactic IABP strategy after primary PTCA in hemodynamically stable high risk patients with AMI does not decrease the rates of infarct-related artery reocclusion or reinfarction, promote myocardial recovery or improve overall clinical outcome.

(J Am Coll Cardiol 1997;29:1459–67)     

Long-term Follow-up of the Trial of Routine Angioplasty and Stenting After Fibrinolysis to Enhance Reperfusion in Acute Myocardial Infarction (TRANSFER-AMI)

Background

The Trial of Routine Angioplasty and Stenting after Fibrinolysis to Enhance Reperfusion in Acute Myocardial Infarction (TRANSFER-AMI) demonstrated superiority of routine early coronary angiography (and percutaneous coronary intervention [PCI]) compared with standard therapy in fibrinolytic-treated patients with ST-segment elevation myocardial infarction (STEMI) at 30 days. The aim of the current study was to evaluate the long-term (>7 year) effects of an early invasive strategy.

直接经皮冠状动脉介入治疗与溶栓后即刻和补救经皮冠状动脉介入治疗对急性心肌梗死患者近期心功能的影响

目的评价直接经皮冠状动脉介入治疗(PCI)与小剂量重组组织型纤溶酶原激活物(rt-PA)溶栓后即刻和补救PCI对急性心肌梗死(AMI)患者的有效性和安全性,并观察其对近期左心室重构及功能的影响.方法对初次发病、发病6 h内且无溶栓禁忌证的AMI患者63例随机给予直接PCI(直接PCI组,32例)或小剂量rt-PA溶栓加即刻和补救PCI(溶栓加补救PCI组,31例)治疗,于术后3 d、30 d、90d行二维超声心动图检查并记录有关心脏事件.结果术后3 d、30 d、90d两组间左心室收缩末期容积指数(ESVI)、左心室舒张末期容积指数(EDSI)、左心室射血分数(EF)和室壁运动指数(WMSI)均无显著差异(P＞0.05);各组内30 d、90d与3 d比较均有显著差异;依据首次造影血流是否达心肌梗死溶栓治疗临床试验(TIMI)3级将所有患者再分为两组.首次造影达TIMI血流3级者与未达TIMI3级者30d、90d各指标均显著改善.结论直接PCI与小剂量rt-PA溶栓后即刻和补救PCI同样安全有效,改善左心室功能并降低心脏事件的发生.     

Randomized,Double-Blind Study Comparing Saruplase With Streptokinase Therapy in Acute Myocardial Infarction: The COMPASS Equivalence Trial

Objectives. This study sought to demonstrate the equivalence of saruplase and streptokinase in terms of 30-day mortality.Background. The use of thrombolytic agents in the treatment of acute myocardial infarction is well established and has been shown to substantially reduce post-myocardial infarction mortality.Methods. Three thousand eighty-nine patients with symptoms compatible with those of acute myocardial infarction for <6 h entered the study at a total of 104 centers and were randomized to receive streptokinase (1.5-MU infusion over 60 min) or saruplase (20-mg bolus and 60-mg infusion over 60 min). In the saruplase group, a bolus of heparin (5,000 IU) was administered before saruplase, and a corresponding blinded double-dummy placebo bolus was administered before streptokinase. All patients received intravenous heparin infusions for ≥24 h starting 30 min after the end of the thrombolytic infusions; the infusions were titrated to maintain an activated partial thromboplastin time at 1.5 to 2.5 times that of normal.Results. Death of any cause up to 30 days after randomization occurred in 88 (5.7%) of 1,542 patients randomized to receive saruplase and 104 (6.7%) of 1,547 patients randomized to receive streptokinase (odds ratio 0.84, p < 0.01 for equivalence). Hemorrhagic strokes occurred more often in patients receiving saruplase (0.9% vs. 0.3%), whereas thromboembolic strokes were more prevalent in the streptokinase-treated patients (0.5% vs. 1.0%). The rate of bleeding was similar in the two treatment groups (10.4% vs. 10.9%). Hypotension and cardiogenic shock occurred less frequently in the saruplase group. Reinfarction rates were similar.Conclusions. Saruplase is a clinically safe and effective thrombolytic medication. This profile ranks saruplase favorably among the currently available thrombolytic agents.