A matched comparison of the combination of prehospital thrombolysis and standby rescue angioplasty with primary angioplasty

This study sought to assess the rate of acute Thrombolysis In Myocardial Infarction (TIMI) trial grade 3 patency that can be achieved with the combination of prehospital thrombolysis and standby rescue angioplasty in acute myocardial infarction. No large angiographic study has been performed after prehospital thrombolysis to determine the 90-minute TIMI 3 patency rate in the infarct-related artery. Hospital outcome and artery patency were compared to 170 matched patients treated with primary angioplasty. Prehospital thrombolysis was applied 151+/-61 minutes after the onset of pain in 170 patients (56+/-12 years, 86% men), using recombinant tissue-type plasminogen activator, streptokinase, or eminase. Emergency 90-minute angiography was performed in every case. All patients in whom thrombolysis failed underwent rescue angioplasty. After thrombolysis alone, TIMI grade 3 flow in the infarct-related artery was observed in 108 patients (64%), TIMI grade 2 in 12 (7%), and TIMI grade 0 or 1 in 50 (29%). Rescue angioplasty was successful in 47 of 50 attempts. Overall, TIMI 3 patency was achieved in 91%, and additionally TIMI 2 flow in 7% of patients, an average of 113+/-39 minutes after thrombolysis and 55+19 minutes after admission. Therefore, < 2 hours after thrombolysis, only 2% of patients had persistent occlusion (TIMI 0 or 1) of the infarct-related artery. In-hospital mortality was 4% overall (7 of 170), and 3% in the 155 patients in whom TIMI 3 was obtained during the acute phase. Severe hemorrhagic complications occurred in 14 patients (8%) with 2 fatal cerebral hemorrhages (7% of patients required transfusions). The matched comparison with primary PTCA showed no significant difference in hospital outcome. Combined prehospital thrombolysis, 90-minute angiography, and rescue angioplasty yield a high rate of acute TIMI 3 patency rate early after thrombolysis and hospital admission. A randomized, prospective comparison between these 2 reperfusion strategies may be now warranted.     

Fate of patients with acute myocardial infarction with patency of the infarct-related vessel achieved with successful thrombolysis versus rescue angioplasty.

Patients with failure of infarct-related artery recanalization after thrombolytic therapy have a poor clinical outcome. These patients have been considered for rescue angioplasty 90 min after thrombolytic therapy at the time of emergency catheterization in the course of five Thrombolysis and Angioplasty in Myocardial Infarction (TAMI) trials. The outcome of 776 patients with patent infarct-related vessels after emergency catheterization was analyzed--607 with thrombolysis-mediated patency of the infarct-related vessel and 169 with patency achieved by angioplasty. Baseline characteristics of the thrombolysis and angioplasty patency groups were similar except for a higher acute left ventricular ejection fraction (51.3% versus 48.2%) in the thrombolysis group (p = 0.003). Seven to 10 day left ventricular ejection fraction was higher (52.3% versus 48.1%), infarct zone functional recovery was greater (0.44 versus 0.21 standard deviation/chord, or 18% versus 7%, p = 0.001) and reocclusion was less (11% versus 21%) in the thrombolysis compared with the angioplasty group. Despite these differences, angioplasty patency was associated with the same low in-hospital mortality rate (5.9% versus 4.6%) and long-term mortality rate (3% versus 2%) as thrombolysis patency. Reocclusion adversely affected the mortality rate and ventricular functional recovery. Technical failure of rescue angioplasty was associated with a much higher mortality rate than was technical success (39.1% versus 5.9%). Thrombolysis patency was preferable to angioplasty patency after thrombolytic therapy in acute myocardial infarction, but both were associated with the same low in-hospital and long-term mortality rates, suggesting that rescue angioplasty is beneficial in some patients with failure of infarct-related artery recanalization after thrombolytic therapy.     

Acute myocardial infarction with patent infarct-related artery: selection of treatment based on qualitative analysis of coronary angiograms during the acute phase

To evaluate the benefit of emergency coronary angioplasty (PTCA) among patients with acute myocardial infarction having patent infarct-related arteries, we investigated 104 patients who received thrombolysis and/or PTCA within 24 hrs after onset of symptoms. The morphology of coronary artery lesions was qualitatively assessed by angiography and categorized as symmetrical or asymmetrical narrowing with smooth margins (S-group, 72 cases) and asymmetrical narrowing in the form of convex intraluminal obstruction representing a thrombus (T-group, 32 cases). Soon after intervention, angiographic success (residual stenosis less than 75%) was achieved in 85% with PTCA (92% in the T-group vs 82% in the S-group) and in 29% without PTCA (53% vs 16%). At hospital discharge, the figures were 82% with PTCA (75% vs 87%) and 43% without PTCA (73% vs 30%). The incidence of re-infarction and/or total occlusion of the infarct-related artery was 9% with PTCA in both the T- and S-groups but 26% in those without PTCA (6% in the T-group vs 31% in the S-group). These data suggest that in patients with patient infarct-related arteries and severe original stenosis, PTCA has an advantage over thrombolysis alone. Qualitative analysis of coronary morphology by angiography provides a framework for selecting adequate therapy.     

Acute myocardial infarction: immediate coronary angioplasty for failure or contra-indications of thrombolytic therapy. Apropos of a series of 100 cases

One hundred patients admitted to a centre of interventional cardiology with acute myocardial infarction of less than 6 hours, underwent coronary angioplasty of first intention because of contra-indications to thrombolytic therapy (n = 20) or after thrombolytic therapy with streptokinase (n = 54), acylenzymes (n = 12) or tissue type plasminogen activator (n = 14). The indication of angioplasty were those of the TIMI (Thrombolysis in Myocardial Infarction) classification (occluded artery, TIMI grade 0) (n = 60) (suboccluded artery, TIMI grade 1) (n = 40). The criterion of success of angioplasty was an increase greater than 1 of TIMI grade. Reperfusion of the coronary artery was obtained by angioplasty in 95% of failures of thrombolysis and in 90% of patients with contra-indications to thrombolytic therapy. The early reocclusion rate at D1 was 2%. Repeat angioplasty at D1 was successful in both these cases and the arteries were still patent at D21. The reocclusion rate at the third week in 75 patients who underwent control coronary angiography was 5.3%. In patients with arterial occlusion, immediate angioplasty attained two objectives in the same procedure: a high rate of emergency myocardial reperfusion and a low rate of reocclusion. The average left ventricular ejection fraction (all arteries) significantly improved (+9.2% in absolute values) when the artery remained patent (p less than 0.001), especially when the initial ejection fraction was low. In the patients who had occluded arteries at control angiography at 3 weeks, the ejection fraction decreased (-4% in absolute values) (NS). The following complications were observed: 4 coronary artery dissections and haematomas at the site of femoral puncture in patients who had received thrombolytic therapy (10 drained surgically). The hospital mortality was 3% and global mortality after an average follow-up period of 19.6 months was 5%. Coronary angioplasty in acute myocardial infarction carries a low risk and seems to be beneficial in patients with contra-indications to or failure of thrombolysis.     

Determinants of recurrent ischaemia and revascularisation procedures after thrombolysis with recombinant tissue plasminogen activator in primary coronary occlusion

This paper reports the immediate effects of thrombolysis and their subsequent influence on revascularisation procedures and clinical outcome over the subsequent twelve months. Coronary arteriography was performed at 21 days on 131 of 145 patients who received recombinant tissue plasminogen activator (n = 68) or placebo (n = 63) within 2.5 hours of symptom onset after primary coronary occlusion. Patency rates (TIMI grades 2 and 3) of the infarct-related artery were 81% with plasminogen activator and 63% with placebo (P = 0.02). Early (within 21 days) angiography for recurrent ischaemia was necessary in 31 (21%) patients (20 plasminogen activator, 11 placebo NS) and definite reinfarction occurred in 8 (5%) patients (4 plasminogen activator, 4 placebo). During one year follow-up without planned secondary intervention, coronary artery bypass grafting was more frequent in patients who had received thrombolytic therapy (23% plasminogen activator, 4% placebo P = 0.001); coronary angioplasty procedures were similar in both groups (12% plasminogen activator, 11% placebo NS). Mortality at 21 days was 5% (4 plasminogen activator, 4 placebo) and at one year was 7% (5 plasminogen activator, 5 placebo). Logistic regression analysis identified models comprising characteristics predictive of subsequent bypass grafting (plasminogen activator, multivessel disease, occluded infarct-related artery) and coronary angioplasty (non-q wave infarction, severe (91-99%) residual stenosis, left anterior descending infarct-related artery). Initial non-q wave infarction was the only predictor of early recurrent ischemia (odds ratio 4, P = 0.02) irrespective of residual stenosis severity.     

Restoration of coronary blood flow by single bolus injection of the gpiib/iiia receptor antagonist c7e3 fab in a patient with acute myocardial infarction of recent onset

It has been debated that primary coronary angioplasty could be more effective if immediate antithrombotic therapy would contribute to a faster recanalization of the infarct-related artery. This is the first report of a patient who presented at the emergency department with acute anterolateral myocardial infarction, in whom a single bolus injection of c7E3 Fab (0.25 mg/kg body weight) led to complete reperfusion of the infarct-related coronary artery during organization time for planned acute coronary angioplasty. Pain relief 15 min after initiation of therapy and ST-segment resolution of >50%, as well as occurrence of idioventricular rhythm 30 min thereafter, were suggestive of successful recanalization before the coronary intervention was started. Diagnostic coronary angiography at 90 min revealed TIMI-grade 3 flow in the infarctrelated coronary artery with only moderate luminal irregularities. Bolus administration of c7E3 Fab could be effective for dissolving platelet-rich thrombi in the early stage of acute myocardial infarction (AMI) and may therefore represent a promising “bridging” therapy in patients with AMI elected for primary coronary angioplasty.     

Rescue coronary stenting with heparin-coated Jostents for failed thrombolysis in acute myocardial infarction

The aim of the present study was to assess the procedural safety and in-hospital and long-term effectiveness of heparin-coated Jostents after failed thrombolysis in acute myocardial infarction. We prospectively analyzed the acute and long-term clinical and angiographic outcomes of 35 consecutive patients treated with heparin-coated Jostents for thrombolytic failure. Rescue coronary stenting was successful in 34 of 35 patients (97%). Thrombolysis in Myocardial Infarction flow grade 3 was obtained in 31 patients (88.5%). The only patient with procedural failure died from cardiogenic shock a day after the procedure. One patient (2.8%) underwent an emergency coronary bypass operation because of angiographic evidence of stent thrombosis with re-infarction. During in-hospital follow-up, 2 patients (5.7%) underwent an elective coronary bypass operation after successful stent implantation of the infarct-related artery because of existing severe multivessel coronary artery disease. Minor bleeding complications at the vascular access site occurred in 3 (8.6%) patients. No cerebrovascular or any other major bleeding complication occurred. One patient (2.1%) underwent repeat coronary angioplasty for restenosis and an elective coronary artery bypass operation was performed in one patient (2.8%) during the 294 +/- 150 days follow-up. The rate of target vessel revascularization was 14.3% and the event-free survival rate was 80%. Twenty-six patients (90%) had angiographic follow-up at six months, and stent restenosis was found in 5 (19.2%). This study demonstrates that heparin-coated Jostents are sale, with low in-hospital and long-term mortality rates for the treatment of failed thrombolysis in acute myocardial infarction. The angiographic restenosis and target vessel revascularization rates of this registry are also acceptable.     

Recurrent ischemia without warning. Analysis of risk factors for in-hospital ischemic events following successful thrombolysis with intravenous tissue plasminogen activator

Ischemic events after successful thrombolysis have been reported to occur in 18-32% of patients treated for acute myocardial infarction with thrombolytic therapy, and previous studies in which patients received streptokinase suggest that risk of early recurrent ischemia is closely related to the presence of a high-grade residual stenosis. If these events are predictable after intravenous recombinant tissue-plasminogen activator (rt-PA) thrombolytic therapy, then further intervention after its use could be targeted at selected patients. One-hundred ninety-two patients from the Thrombolysis and Angioplasty in Myocardial Infarction (TAMI) I and TAMI III trials had successful rt-PA-mediated thrombolysis without immediate coronary angioplasty (PTCA). One-hundred seventy-four of these patients (92%) had prehospital discharge angiography. The mean age was 56 +/- 11 years; 81% were men; the infarct-related artery was the left anterior descending in 76 (39.8%), the left circumflex in 24 (12.6%), and the right coronary artery in 91 (47.6%). Thrombolysis with rt-PA resulted in a residual 73 +/- 13% diameter and 0.95 +/- 0.51 mm stenosis by quantitative coronary arteriography, and Thrombolysis in Myocardial Infarction (TIMI) flow grade 2 in 59.2% and 3 in 40.8% of stenoses as assessed on angiograms obtained 90 minutes after the initiation of rt-PA therapy. Recurrent ischemic events (ischemia requiring emergency percutaneous transluminal coronary angioplasty or urgent bypass surgery, reocclusion of the infarct-related artery, or cardiac death) occurred in 41 patients (21.3%).(ABSTRACT TRUNCATED AT 250 WORDS)     

尿激酶溶栓治疗急性心肌梗死成功后相关冠状动脉形态动态观察

目的:观察急性心肌梗死(AMI)尿激酶溶栓成功后相关冠状动脉(冠脉)形态动态改变。方法:以溶栓成功的42例患者为观察对象,溶栓后90min和6个月时分别对其进行冠脉造影,然后用计算机辅助定量冠脉造影系统对溶栓后的冠脉病变处进行测量。结果:溶栓后90min42例患者中5例残余狭窄为90%～95%,32例残余狭窄为70%～90%,4例残余狭窄<50%,1例无明显狭窄;与溶栓后90min相比较,溶栓后6个月时34例患者残余狭窄无明显改变(P>0.05),7例残余狭窄明显改善(P<0.05)。结论:AMI静脉溶栓虽可挽救一部分濒临坏死的心肌,但大部分相关冠脉仍留有明显的残余狭窄,仍需行经皮冠脉介入术来解决残余狭窄问题。     

Prevention of subsequent exercise-induced periinfarct ischemia by emergency coronary angioplasty in acute myocardial infarction: comparison with intracoronary streptokinase

To compare the efficacy of emergency percutaneous transluminal coronary angioplasty and intracoronary streptokinase in preventing exercise-induced periinfarct ischemia, 28 patients presenting within 12 hours of the onset of symptoms of acute myocardial infarction were prospectively randomized. Of these, 14 patients were treated with emergency angioplasty and 14 patients received intracoronary streptokinase. Recatheterization and submaximal exercise thallium-201 single photon emission computed tomography were performed before hospital discharge. Periinfarct ischemia was defined as a reversible thallium defect adjacent to a fixed defect assessed qualitatively. Successful reperfusion was achieved in 86% of patients treated with emergency angioplasty and 86% of patients treated with intracoronary streptokinase (p = NS). Residual stenosis of the infarct-related coronary artery shown at predischarge angiography was 43.8 +/- 31.4% for the angioplasty group and 75.0 +/- 15.6% for the streptokinase group (p less than 0.05). Of the angioplasty group, 9% developed exercise-induced periinfarct ischemia compared with 60% of the streptokinase group (p less than 0.05). Thus, patients with acute myocardial infarction treated with emergency angioplasty had significantly less severe residual coronary stenosis and exercise-induced periinfarct ischemia than did those treated with intracoronary streptokinase. These results suggest further application of coronary angioplasty in the management of acute myocardial infarction.     

Irregular coronary lesion morphology after thrombolysis predicts early clinical instability.

After successful thrombolytic treatment for acute myocardial infarction, recurrent ischemia and infarction may occur with little warning. Coronary lesion morphology was analyzed from angiograms performed in 72 consecutive patients at 1 to 8 days after streptokinase treatment for acute myocardial infarction and the data were evaluated in relation to the subsequent clinical course. All patients were clinically stable at the time of angiography and continued to receive heparin infusion for greater than or equal to 4 days after thrombolysis. The infarct-related artery was patent in 55 patients (76%). In the 10 days after angiography, 15 patients developed prolonged episodes of angina at rest; the condition of 4 stabilized with medical treatment, but 11 required urgent medical intervention (coronary angioplasty in 8 and bypass surgery in 3). There were no differences in age, gender, left ventricular function or extent of coronary artery disease between those patients who developed unstable angina and those who had a stable in-hospital course. However, the median plaque ulceration index of the infarct-related lesion was 6.7 (95% confidence limits 6.3, 10) in the 15 patients with an unstable course versus 3.3 (2, 4.4) in those with a stable course (p less than 0.001). There were no differences between the two patient groups in the severity of stenosis, length of diseased segment, symmetry/eccentricity, presence of a shoulder, location at branch point or bend, presence of globular or linear filling defects, contrast staining or collateral supply. These data show that after thrombolysis, the degree of irregularity of the infarct-related artery is a critical determinant of early clinical instability.(ABSTRACT TRUNCATED AT 250 WORDS)     

Emergency percutaneous transluminal coronary angioplasty in acute myocardial infarction: a 3 year experience

In 151 patients experiencing acute myocardial infarction, emergency coronary angioplasty was performed as primary therapy. Overall, angioplasty was successful in 132 patients (87%); it was successful in 91 (85%) of 107 patients with a totally occluded infarct-related artery and in 41 (93%) of 44 patients with a subtotally occluded infarct-related artery. After successful angioplasty, mean residual stenosis was 29% (range 0 to 70). Eighteen patients were in cardiogenic shock (12%) including four patients receiving cardiopulmonary resuscitation during the angioplasty procedure. Hospital mortality was 9%, with 7 of 13 deaths occurring in patients presenting with cardiogenic shock or intractable ventricular arrhythmia. Hospital mortality was 5% in patients with successful angioplasty versus 37% in those with unsuccessful angioplasty (p less than 0.001). In the immediate period after angioplasty, left ventricular ejection fraction was significantly lower for patients with lesions of the left anterior descending artery (34 +/- 10%) than for patients with lesions of the left circumflex or right coronary artery (43 +/- 11%). In patients with successful angioplasty, significant improvement in left ventricular ejection fraction averaged 13 +/- 12% (p less than 0.001) for those with lesions of the left anterior descending artery and 10 +/- 12% (p less than 0.001) for those with lesions of the left circumflex or right coronary artery. Repeat coronary angiography was performed in 85 (70%) of 121 patients who had successful angioplasty and survived hospitalization without requiring bypass surgery; restenosis was found in 26 (31%), and angioplasty was repeated in 22 patients, successfully in each.(ABSTRACT TRUNCATED AT 250 WORDS)     

Abciximab in the treatment of acute myocardial infarction eligible for primary percutaneous transluminal coronary angioplasty. Results of the Glycoprotein Receptor Antagonist Patency Evaluation (GRAPE) pilot study.

OBJECTIVES: We sought to study the effect of early infusion of abciximab on coronary patency before primary angioplasty in patients with acute myocardial infarction. BACKGROUND: Glycoprotein IIb/IIIa antagonists have proved to be effective in reducing ischemic events associated with coronary angioplasty. The present study explores whether abciximab alone, without administration of thrombolytic therapy, may induce reperfusion in patients with acute myocardial infarction. METHODS: In the Glycoprotein Receptor Antagonist Patency Evaluation pilot study 60 patients with less than 6 h signs and symptoms of acute myocardial infarction eligible for primary angioplasty received in the emergency room a bolus of abciximab 250 microg/kg followed by a 12-h infusion of 10 microg/min. All patients were also treated with an oral dose of 160 mg aspirin and 5,000 IU of heparin intravenously. As soon as possible a diagnostic angiography was performed to evaluate the patency of the infarct-related artery. RESULTS: The median time between onset of symptoms and the administration of the abciximab bolus was 150 min (range 45 to 345), and the median time between abciximab bolus and first contrast injection in the infarct-related artery was 45 min (range 10 to 150). In 24 patients (40%, 95% confidence interval 28% to 52%) Thrombolysis in Myocardial Infarction (TIMI) flow grade 2 or 3 was observed at a median time of 45 min (range 10 to 150) after abciximab bolus; TIMI flow grade 3 was observed in 11 patients (18%, 95% confidence interval 9% to 28%). There was no difference in percentage of TIMI flow grade 2 or 3 between patients who received abciximab within 2.5 h after onset of symptoms or thereafter. CONCLUSIONS: Abciximab therapy given in the emergency room in patients awaiting primary angioplasty is associated with full reperfusion (TIMI flow grade 3) in about 20% and with TIMI flow grade 2 or 3 in about 40% of the patients at a median time of 45 min. These figures are higher than those in primary angioplasty trials without such pretreatment. Randomized controlled trials of very early infusion of abciximab, either prehospital or in-hospital, in patients eligible for angioplasty are warranted.     

Improved thrombolysis with a modified dose regimen of recombinant tissue-type plasminogen activator

To improve further the patency rate of infarct-related coronary arteries, the following accelerated dosage regimen of recombinant tissue-type plasminogen activator (rt-PA) was administered to 80 patients with acute myocardial infarction of less than or equal to 6 h duration: 15 mg intravenous bolus, 50 mg infusion over 30 min and 35 mg infusion over the following 60 min. After coronary angiography at 90 min coronary angioplasty was performed in 16 patients and additional thrombolysis in 3 patients. Six patients were not included in the final angiographic analysis, mostly because of borderline ST segment elevations, in order to avoid overestimation of the efficacy of this dose regimen. Four of these had a patent infarct artery; no early angiogram was performed on two. Sixty minutes after the start of infusion, 54 (74%) of 73 patients had a patent infarct-related artery (Thrombolysis in Myocardial Infarction [TIMI] grade 2 or 3) as did 67 (91%) of 74 patients at 90 min. At 24 h, 61 (92.4%) of 66 patients showed a patent infarct artery. Recurrent myocardial ischemia was noted in 12 patients, 7 (9.4%) of whom experienced reinfarction during the hospital stay. Minor local bleeding complications were observed in 14 patients (17.5%). There were four in-hospital cardiac deaths; one patient who underwent additional thrombolysis for recurrent ischemia died from bleeding complications. These results show that a rapid infusion of 100 mg of rt-PA over 90 min yields a high early patency rate of the infarct-related artery without an increase in reocclusion rate and adverse reactions.     

Evaluation of lesions suitable for percutaneous transluminal coronary angioplasty after thrombolytic therapy of acute myocardial infarction

Forty-two patients of acute myocardial infarction (AMI) and clinically successful thrombolysis underwent coronary angiography 7.6 +/- 3.6 days after the AMI. The infarct related artery was patent in 33 of 42 (78.5%) patients, and 27 of these 33 (82%) had residual diameter stenosis of 70 per cent or more. Arteries showing more than 70 per cent luminal diameter narrowing were considered suitable for percutaneous transluminal coronary angioplasty (PTCA) if the lesion was less than 1 cm in length and there was no significant left main or distal lesion. Based on the above criteria, 22 of the 33 patients (66%) with recanalised infarct-related artery were found to have lesions suitable for PTCA. Thus, after successful thrombolysis, significant proportion of patients of acute myocardial infarction have residual lesions that are suitable for PTCA.     

Arrhythmias during the acute phase of reperfusion therapy for acute myocardial infarction: effects of beta-adrenergic blockade.

In 107 patients with acute myocardial infarction, the incidence of ventricular arrhythmias during the acute phase of thrombolysis was examined by means of Holter monitoring. In patients with a patient infarct-related artery as assessed angiographically at 90 minutes, the occurrence of accelerated idioventricular rhythms was noted significantly more frequently than in patients with a permanent occluded vessel. This arrhythmia peaked in the first 180 minutes after the start of thrombolysis. In addition, single ventricular premature beats and runs of ventricular tachycardia were also more common in patients with successful reperfusion. The effects of acute intravenous administration of beta-blockers were examined in 66 patients without contraindications to this therapeutic approach. There were no differences in the occurrence of any type of rhythm disorders in patients with (n = 43) or without beta-blockade (n = 23). Thus ventricular arrhythmias particularly accelerated idioventricular rhythms, and single ventricular premature beats occur more frequently in patients with a patent infarct artery within the first 24 hours after thrombolysis. Acute intravenous beta-blockade does not appear to exert significant antiarrhythmic effects during this period.     

Late arrhythmic events and patency of the infarct-related coronary artery in survivors of acute myocardial infarction.

In the present study we evaluated the influence of intravenous thrombolysis and patency of the infarct-related coronary artery on both markers of ventricular electrical instability and incidence of late arrhythmic events after acute myocardial infarction (AMI). Ninety one patients surviving a first AMI who consecutively performed coronary angiography were enrolled in the present study; 44 patients (48%) received thrombolysis, 47 patients (52%) were treated conventionally. Of 91 patients, 90 (99%) had signal-averaged electrocardiogram (SAECG), and 40 (44%) programmed ventricular stimulation. No significant difference was observed between thrombolytic-treated and control group in late potential rate, SAECG determinants and ventricular arrhythmia inducibility. Of 91 patients, 40 (44%) had occlusion of the infarct-related artery: of these, 15 (37%) had late potentials compared with 5 of 51 patients (9%) with a patent artery (p < 0.01). Mean left ventricular ejection fraction was not significantly different between the two groups (0.50 +/- 0.15 vs 0.55 +/- 0.12; p = NS). No significant difference was present between the two groups of patients with regard to inducibility of sustained ventricular tachyarrhythmias, however an odds ratio of 3.5 was observed in the group with a closed vessel.(ABSTRACT TRUNCATED AT 250 WORDS)     

Self-expanding stents for emergency treatment of acute vessel closure following coronary angioplasty: immediate and long-term results

Intracoronary stents may be used to treat acute coronary occlusion following balloon angioplasty. We report the immediate and long-term results of emergency implantation of the self-expanding stent (Wallstent) in 39 patients with acute vessel closure. Stents were successfully deployed in 38 patients (97%). Procedural complications occurred in 14 patients (36%); one patient died, two required emergency coronary artery bypass graft surgery, nine sustained myocardial infarcts (one Q wave), and two had acute stent thrombosis successfully treated by intracoronary thrombolysis and repeat angioplasty. Four patients (10%) had femoral artery bleeding, two required surgery. Angiographic follow-up was performed after 6 months in all 34 eligible patients, or earlier for symptoms. Two patients died prior to follow-up angiography. The stented segment was widely patent in 27 of the 34 patients (79%); restenosis within the stent was detected in 4 (12%) and thrombotic stent occlusion occurred in three (9%). Twenty-six of the 39 patients (67%) were free from major cardiac events and symptoms at 1 year. These results suggest that the self-expanding stent provides an attractive alternative to emergency surgery for the treatment of acute coronary occlusion following coronary angioplasty.     

Relationship between the preexistent coronary collateral circulation and successful intracoronary thrombolysis for acute myocardial infarction.

The purpose of this study was to evaluate whether the existence of coronary collateral circulation influences recanalization rates of intracoronary thrombolysis. The study population consisted of 85 consecutive patients undergoing intracoronary thrombolysis within 6 hours after the onset of the first acute myocardial infarction, all of whom had a complete occlusion of the infarct-related coronary artery. Intracoronary thrombolysis with high-dose urokinase (960,000 IU) was attempted at a rate of 24,000 IU/min. Of 18 patients (group A) who had good angiographic collateral circulation to the area perfused by the infarct-related coronary artery, the obstructed artery was recanalized to a residual luminal diameter stenosis of less than or equal to 90% (successful recanalization) in only five (28%). In contrast, of 67 patients (group B) with poor or no collateral circulation, recanalization was successful in 40 (60%) (p less than 0.05). Antegrade flow of infarct-related arteries was observed following thrombolysis in 12 (67%) of 18 group A patients and in 56 (84%) of 67 group B patients (p = NS). It was concluded that (1) the presence of collaterals correlates with the presence of high-grade stenosis; (2) the presence of collaterals correlates with the presence of high-grade stenosis; (2) the presence of collaterals is inversely related to the efficacy of thrombolytic therapy; and (3) the difference in successful recanalization rates observed between the two groups probably reflects the impact of underlying stenosis severity on the effectiveness of lytic therapy.     

Clinical significance of coronary flow to the infarct zone before successful primary percutaneous transluminal coronary angioplasty in acute myocardial infarction

STUDY OBJECTIVE: To assess the effect of coronary flow to the infarct zone before primary coronary angioplasty on hospital complications in patients with acute myocardial infarction (MI). DESIGN: Consecutive case series analysis. SETTING: Coronary-care unit in a university hospital. PATIENTS: Two hundred sixty-four consecutive patients with ST-elevation acute MIs who had successful primary percutaneous transluminal coronary angioplasty. INTERVENTIONS: Coronary angiography on hospital admission and serial echocardiography. MEASUREMENTS AND RESULTS: The status of infarct-related artery flow before primary angioplasty was evaluated on hospital admission. Left ventricular wall motion and pericardial effusions were studied by echocardiography. One hundred ninety patients had total occlusions (Thrombolysis in Myocardial Infarction [TIMI] flow grade, 0 to 1) in the infarct-related artery (group 1), and 74 patients had antegrade flow (TIMI flow grade, 2 to 3) [group 2] before undergoing primary angioplasty procedures. When group 1 was subdivided into two groups (for the presence and absence of collateral flow), the patients with total occlusions and no collateral flow had a higher incidence of left ventricular aneurysmal wall motion (11% vs 1%, respectively; p = 0.03) and pericardial friction rub (15% vs 3%, respectively; p = 0.03) than did those in group 2. Moreover, those patients with total occlusions and no collateral flow had higher incidences of pericardial effusion (34% vs 17%, respectively; p = 0.02; and 34% vs 9%, respectively; p < 0.01) and in-hospital mortality (8% vs 1%, respectively; p = 0.04; and 8% vs 1%, respectively; p = 0.06) than did those patients in the other two groups. CONCLUSIONS: Despite successful primary angioplasty, the absence of antegrade flow in the infarct-related artery and collateral flow to the infarct zone before angioplasty resulted in a higher incidence of in-hospital complications.