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.     

Percutaneous transluminal coronary angioplasty in evolving acute myocardial infarction

In 29 patients with evolving acute myocardial infarction, acute reperfusion of the infarct-related coronary artery was attempted using percutaneous transluminal coronary angioplasty (PTCA). Before PTCA, angiography showed 23 totally occluded and 6 severely stenotic infarct-related coronary arteries. PTCA was initially successful in 25 of 29 patients (86%). Reocclusion occurred in 4 patients within 12 hours after successful PTCA and was associated with new electrocardiographic changes or recurrence of symptoms. In 17 patients the infarct-related coronary artery remained patent at early follow-up; late stenosis occurred in 4 patients. Recurrence of stenosis was accompanied by development of angina. No clinical or angiographic features distinguished those with ultimate vessel patency, occlusion or recurrence of stenosis. On follow-up, ventricular function appeared better preserved or improved in those with a patent infarct-related coronary artery than in those with an occluded infarct-related coronary artery. Further studies are warranted to compare PTCA and streptokinase as primary reperfusion modalities in evolving acute myocardial infarction.     

Improvement in three-month angiographic outcome suggested after primary angioplasty for acute myocardial infarction (Zwolle trial) compared with successful thrombolysis (APRICOT trial). Antithrombotics in the Prevention of Reocclusion In COronary Thrombolysis.

It has been shown that primary percutaneous transluminal coronary angioplasty (PTCA) for acute myocardial infarction results in higher patency rates than thrombolytic therapy. However, no data are available on differences in long-term angiographic outcome after successful primary PTCA compared with successful thrombolysis. Therefore, we compared angiographic data of the Antithrombotics in the Prevention of Reocclusion In COronary Thrombolysis (APRICOT) trial and the Zwolle primary PTCA trial. In the APRICOT trial 248 patients underwent coronary angiography at a mean of 24 hours after thrombolysis and had a patent infarct-related vessel (Thrombolysis In Myocardial Infarction-3 trial flow) when entering the study. Reocclusion rates were assessed at a second angiography after 3 months. In the Zwolle trial 136 patients had a successful primary PTCA. At 3 months 131 patients underwent a second angiography. Quantitative coronary angiography showed a significant lower mean diameter stenosis of the infarct-related vessel after primary PTCA (27 +/- 12% vs 57 +/-12%; p = 0.00001). At 3 months this difference was sustained (35 +/- 22% vs 63 +/- 26%; p = 0.00001). After thrombolysis the reocclusion rate at 3 months was 29% compared with 5% after primary PTCA (p = 0.0001). Results show that compared with successful thrombolytic therapy, primary PTCA for acute myocardial infarction results in an improved infarct-related vessel status not only short term but also long term, with a low reocclusion rate.     

Follow-up after coronary arterial reperfusion with intravenous streptokinase in relation to residual myocardial infarct artery narrowings

Short- and long-term changes in residual stenosis of the myocardial infarct-related coronary arteries in patients with successful reperfusion by intravenous streptokinase have not been determined until now. In 15 patients the residual diameter stenosis decreased significantly from 62 +/- 9% after 24 hours to 55 +/- 13% in the fourth week (p less than 0.005). Quantitative angiographic analyses in 61 patients with patent infarct-related coronary arteries in the fourth week revealed a mean diameter stenosis of 61 +/- 13%. The patients were followed up 34 +/- 10 months. Sixteen had elective coronary artery bypass surgery or percutaneous transluminal coronary angioplasty (PTCA). Eighteen without coronary artery bypass surgery or PTCA had undergone repeat angiography after 26 +/- 9 months. Twenty-five (41%) have had a residual diameter stenosis greater than 65% in the fourth week. A stenosis greater than 65% was found in: 4 of 5 patients with late reinfarction; 3 of 7 with 1-vessel coronary artery disease and persistent angina, compared with none of 11 with a stenosis less than 65%; 6 of 7, whose silent reocclusion had been found at long-term follow-up compared with 1 of 9 with a residual stenosis less than 65%. In 8 patients with persistent patency of the infarct artery, the stenosis had decreased significantly from 55 +/- 6% to 36 +/- 12% (p less than 0.005). Correspondingly, there was a significant improvement in the infarct-related left ventricular wall motion disorders.(ABSTRACT TRUNCATED AT 250 WORDS)     

Assessment of residual coronary arterial stenosis after thrombolytic therapy during acute myocardial infarction

Maximal myocardial salvage appears to be related to the severity of residual coronary arterial stenosis after thrombolysis. The degree of residual infarct vessel stenosis was assessed in 119 consecutive patients with patent arteries who received streptokinase during acute myocardial infarction. After administration of streptokinase, 99 of 119 patients (83%) had a residual stenosis 70% or more in diameter. Assuming that a residual diameter stenosis of at least 70% is flow limiting, the feasibility for percutaneous transluminal coronary angioplasty (PTCA) was determined by the following criteria: length less than 10 mm, no significant distal narrowing or left main stenosis, and an adequate-sized distal artery. In 81 of 99 patients (82%), arterial anatomy was suitable for PTCA. Thus, after therapy with streptokinase for acute myocardial infarction, most patients have a significant infarct arterial residual stenosis and are candidates for PTCA.     

Incidence of residual thrombi following successful thrombolytic therapy in acute myocardial infarct and their significance for the rate of early re-occlusion. A report of a multicenter dose-finding study for thrombolytic therapy with urokinase preactivated natural prourokinase (TCL 598)

Thrombolysis with urokinase preactivated prourokinase was performed in 74 patients. At control angiography, 90 min into thrombolysis, in 39 (52.7%) patients the infarct-related coronary artery was found patent. However, 26 out of the 39 patients (66.7%) with a patent infarct artery demonstrated angiographic signs of residual coronary thrombi. With an estimated average of 75 +/- 25% in both, patients with and without residual thrombus, the severity of the residual stenosis after thrombolysis was found to be independent from the presence of angiographic signs of residual coronary artery thrombosis. In patients with residual coronary thrombi, however, a trend towards poorer coronary perfusion was observed (50% vs 77% of the patients with prompt antegrade [TIMI grade III] perfusion [p less than 0.2]. Control angiography performed 24 to 36h after thrombolysis revealed reocclusion of the infarct artery in 26.3% of the patients with residual coronary thrombi, while none of the infarct vessels without angiographic signs of residual thrombosis had reoccluded (p less than 0.05). At follow-up angiography 17 to 23 days after thrombolysis this difference in the incidence of reocclusions had further increased to 43.8% of patients with vs 12.5% of patients without residual coronary thrombus (p less than 0.01). Thus, after thrombolysis, residual thrombotic material remaining in the infarct related vessel seems to be a major risk factor, indicating early reocclusion of the infarct artery.     

Angiographic patterns of restenosis after angioplasty of multiple coronary arteries

To assess angiographic patterns of restenosis after percutaneous transluminal coronary angioplasty (PTCA) of multiple coronary arteries, angiograms were reviewed in 40 patients with clinical recurrence after PTCA of multiple arteries. Clinical recurrence was defined as return of symptoms after successful PTCA of more than 1 major artery or branch and angiographic evidence of restenosis of 1 or more lesions. In these 40 patients, 83 arteries (2.1 arteries per patient) and 103 narrowings (2.6 narrowings per patient) were successfully dilated. Restenosis developed in 57 of 83 arteries at risk (69%): 23 patients (58%) had restenosis in only 1 artery and 17 (42%) in 2 arteries. Restenosis occurred in 63 of 103 lesions at risk (61%): 20 patients (50%) had restenosis of 1 narrowing, 17 (43%) had restenosis of 2 narrowings and 3 (7%) had recurrence of 3 narrowings. Only 13 patients (33%) had restenosis of all narrowings dilated. Predictors of restenosis of individual narrowings were: higher pre-PTCA percent stenosis (87 +/- 10% in narrowings with restenosis vs 82 +/- 10% in narrowings without, p less than 0.02), and higher degree of residual stenosis after PTCA (46 +/- 13% in narrowings with restenosis vs 36 +/- 12% in narrowings without, p less than 0.001). Balloon size or inflation pressure did not predict recurrence of narrowings. Repeat PTCA was successful in 97% of cases attempted (33 of 34), 3 patients underwent elective bypass surgery and 3 were managed with medical therapy. Most patients with clinical recurrence after PTCA of multiple arteries do not have restenosis of multiple arteries or narrowings, and only one-third will have recurrence of all narrowings.(ABSTRACT TRUNCATED AT 250 WORDS)     

Prediction and prevention of reocclusion after coronary thrombolysis for acute myocardial infarction based on analysis of the coronary morphology with angiography]

Morphology of the affected coronary artery in acute myocardial infarction was qualitatively analyzed to predict the incidence of reocclusion after intracoronary thrombolysis. In 274 patients with 75% or more residual stenosis after successful thrombolysis, the morphology of the stenosis underlying the acute thrombus was graded as 75% or more (type A, n = 195), or less than 75% (type B, n = 79). Eighty-one patients with type A stenosis and 39 of 79 patients with type B stenosis were treated with immediate PTCA following thrombolysis. In 154 patients treated without PTCA, the severity of type A stenosis on chronic angiography remained unchanged after thrombolysis (87 +/- 7%-->86 +/- 14%); whereas, regression of the stenosis was noted in patients with type B stenosis (85 +/- 6%-->53 +/- 32%, p < 0.001). After thrombolysis, reocclusion occurred in 31 of 117 patients with type A stenosis, but in only 2 of 40 patients with type B stenosis (26.5% vs 5.0%, p < 0.02). Reocclusion was prevented by PTCA in patients with type A stenosis (26.5% vs 8.6%, p < 0.01), but not in patients with type B stenosis (5.0% vs 10.3%, p = ns). Qualitative analysis of coronary morphology after thrombolysis can facilitate the prediction of the occurrence of reocclusion and may provide a framework for selection of therapy.     

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)     

Immediate or delayed angioplasty during the acute phase of myocardial infarction. Apropos of 118 cases

The results of immediate percutaneous transluminal coronary angioplasty (PTCA) (260 +/- 167 minutes after onset of pain and an average of 56 minutes after thrombolysis) and deferred PTCA (average 9.6 days, range 1 to 30 days after infarction) were compared in 118 consecutive patients with acute myocardial infarction. The overall primary success rate of PTCA was 82.2 per cent; it was higher in those patients undergoing deferred angioplasty (96% vs 78%; p less than 0.05). The primary success rate of immediate PTCA was related to the severity of the stenosis before dilatation: 75 per cent success in occluded compared to 84 per cent in suboccluded vessels (over 90% stenosis) and 100 per cent success in vessels with under 90 per cent stenosis. Eighty one per cent of failed angioplasties occurred in patients with occluded arteries, the majority being left anterior descending (LAD) arteries (71.4%). The incidence of restenosis was 13.4 per cent. This complication was diagnosed at coronary arteriography performed 40 days after PTCA in 1 case, 47 days after PTCA in another case and at the 6 month control in 11 cases. Reocclusion was observed in 21 patients (21.7% of immediate successes). The occlusion was diagnosed at the first control after an average of 8 days in 15 cases. The interval between the onset of pain and thrombolysis and dilatation was significantly longer in the group with reocclusion compared with patients without reocclusion (314 minutes vs 193 minutes for thrombolysis, p less than 0.01; and 356 minutes vs 204 minutes fort PTCA, p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)     

Management of Patients with Heparin-Induced Thrombocytopenia: Focus on Recombinant Hirudin

It remains controversial whether percutaneous transluminal coronary angioplasty (PTCA) performed 24 hours after the onset of acute myocardial infarction (AMI) in coronary arteries with 99% stenosis is useful in preserving left ventricular function. We investigated the effectiveness of PTCA in preventing left ventricular remodeling when it was performed 24 hours after the onset of AMI in infarct-related coronary arteries (IRCAs) having 99% stenosis and thrombolysis in myocardial infarction (TIMI) grade 3 flow. The subjects were 19 patients with AMI (anterior wall, 9 patients; inferior wall, 7 patients; and non-Q, 3 patients) who, within 24 hours of the onset of AMI, underwent coronary angiography and left ventriculography during the acute and/ or chronic phases. The patients were divided into a PTCA group, comprised of patients in whom PTCA was successfully performed 24 hours after the onset of AMI (n = 10), and a non-PTCA group (n = 9). The non-PCTA group included patients who were successfully reperfused by thrombolysis and did not include patients who had spontaneous reperfusion or reperfusion after PTCA. In the non-PTCA group, the left ventricular end-diastolic volume (mean ± SD) was significantly increased in the chronic phase (86 ± 23 mL/m² as compared with the acute phase (67 ± 13 mL/m², whereas in the PTCA group no significant difference was observed between end-diastolic volumes in the acute and chronic phases (67 ± 26 and 68 ± 13 mL/m², respectively). Left ventricular remodeling is prevented by PTCA when it is performed 24 hours after the onset of AMI in IRCAs with 99% stenosis and TIMI grade 3 flow.     

Utility and limitation of treadmill exercise echocardiography for detecting significant coronary stenosis in infarct-related arteries in patients with healed myocardial infarction.

This clinical study examines the diagnostic accuracy of exercise echocardiography for detecting significant coronary stenoses in infarct-related arteries in patients with healed myocardial infarction. Quantitative coronary angiography and exercise echocardiography using treadmill testing were performed within 2 weeks of each other in 123 patients with a prior myocardial infarction. Coronary lumen diameter stenosis > or =50% by quantitative coronary angiography and the lack of a hyperdynamic response on exercise echocardiography was considered significant. For detection of infarct-related coronary lesions, treadmill exercise echocardiography was highly sensitive (91%) but less specific (59%) than for detection of non-infarct-related artery lesions. The 2 groups of patients with large and small infarct sites had similar sensitivity for detection of residual stenosis of the infarct-related artery (88% vs 96%, p = NS); however, the specificity of the small infarct sites for this purpose was significantly higher than that of the large infarct sites (86% vs 33%, p < 0.01). When remote ischemia was detected on exercise echocardiography, the specificity of exercise echocardiography was significantly lower (33% vs 70%, p < 0.05) than when remote ischemia was not present. Thus, although there is high sensitivity, the specificity of treadmill exercise echocardiography for detecting infarct-related artery lesions is limited. However, high specificity is maintained when the infarct size is small and/or remote ischemia is not present.     

Long-term clinical outcomes after rescue angioplasty are not different from those of successful thrombolysis for acute myocardial infarction.

AIMS: The long-term value of rescue percutaneous transluminal coronary angioplasty (PTCA) in patients with ST-segment elevation myocardial infarction who received thrombolytic therapy but failed to achieve early recanalization of the artery is still debated. This study aimed to compare long-term outcomes after successful thrombolysis vs. systematic attempted rescue PTCA. METHODS AND RESULTS: A total of 362 consecutive patients with STEMI hospitalized within 6 h of symptom onset and treated with intravenous thrombolytic therapy were studied. Of these, 345 underwent coronary angiography within 90 min. Sixty per cent of patients achieved TIMI 3 flow and were treated medically; the in-hospital death rate in this group was 4%. Nine per cent of patients had TIMI 2 flow and 31% TIMI 0-1 flow. In this latter group, rescue PTCA was attempted in 85.8% with a hospital death rate of 5.5% (20% with failed vs. 4% with successful rescue PTCA, P=0.03). Eight year actuarial survival without recurrent myocardial infarction was no different in patients who had successful thrombolytic therapy and in patients with attempted rescue PTCA [78 and 95% CI (71-85) vs. 78 and 95% CI (68-87), respectively, hazard ratio: 0.93 (0.52-1.65), P=0.80]. Total mortality, cardiac mortality, and other composite endpoints also did not differ between groups. CONCLUSION: Routine attempted rescue PTCA 90 min after thrombolytic therapy in patients with persistent occlusion of the infarct-related vessels achieves long-term clinical outcomes which do not differ from those obtained by successful thrombolysis.     

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。     

Degree of residual stenosis in the culprit coronary artery after thrombolytic administration (Thrombolysis In Myocardial Infarction [TIMI] trials)

This study was undertaken to characterize residual stenosis after thrombolytic administration and to evaluate clinical and angiographic features and early outcomes of patients with mild residual obstruction after thrombolytic administration. Patients who underwent angiography at 90 minutes after thrombolytic administration in the Thrombolysis In Myocardial Infarction 4, 10A, 10B, and 14 trials were divided into 3 groups according to the degree of residual stenosis measured by quantitative coronary angiography: patients with a patent culprit artery with <50% stenosis, patients with patent arteries and residual stenosis ≥50%, and patients with occluded arteries. Only 8.9% of the patients (188 of 2,119) had an infarct-related artery luminal diameter stenosis of <50% 90 minutes after thrombolysis. Compared with patients with patent arteries and ≥50% stenosis, patients with mild residual obstruction were younger (56.8 vs 58.6 years; p = 0.03), had fewer prior myocardial infarctions (6.9% vs 13.3%; p = 0.01), fewer eccentric (19.8% vs 42.1%; p <0.0001), ulcerated (7.5% vs 13.2%; p = 0.03), and collateralized (6.6% vs 13.2%, p = 0.01) lesions, but a greater thrombus burden (29.7% vs 18.3%, p = 0.0002). Among patients with patent arteries, a residual stenosis of <50% was associated with a significantly lower composite of in-hospital death, myocardial infarction, and congestive heart failure (2.8% vs 7.1%, p = 0.03). Thus, a minority of patients have a mild residual obstruction at 90 minutes after thrombolytic administration. These patients have less complex lesions with greater thrombus burdens and better clinical outcomes.     

Effects of percutaneous transluminal coronary angioplasty: intracoronary thrombolysis with urokinase in acute myocardial infarction

Coronary angiography and percutaneous transluminal coronary angioplasty (PTCA) were performed in 32 patients with evolving acute myocardial infarction. Of the 25 patients with complete occlusion of an infarct-related coronary artery, in 18 (72%) the occluded vessel was successfully opened by an intracoronary infusion of urokinase. With a small dose of urokinase the successful recanalization was achieved in only 25%; with a larger dose it was achieved in 94%. After PTCA, all patients received glucose-insulin-potassium solution for 76 hours. Repeat angiography 42 days later showed a patent coronary artery in 12 (group A) of 18 patients with successful PTCA. In group A, left ventricular ejection fraction increased from 51 +/- 13% to 72 +/- 10% (p less than 0.01) and regional wall shortening from 4.5 +/- 9.5% to 29 +/- 19% (p less than 0.01). In contrast, these variables did not change significantly in patients with unsuccessful PTCA or late reocclusion of an infarct-related vessel (group B). These data suggest that successful PTCA with sustained patency of an infarct-related coronary artery has a beneficial effect on the salvage of the jeopardized myocardium, and glucose-insulin-potassium therapy may enhance the beneficial effect of PTCA.     

Value of exercise electrocardiography in the detection of restenosis after coronary angioplasty in patients with one-vessel disease.

Exercise treadmill testing (ETT) is considered an unreliable method for detection of restenosis after percutaneous transluminal coronary angioplasty (PTCA). The studies on which this belief is based have used quantitative coronary angiography (QCA) as a reference. The inherent limitations of angiography have been demonstrated by intravascular ultrasound (IVUS). To determine the value of ETT for detecting restenosis when IVUS criteria are used to define restenosis, we studied 29 patients with angiographically documented 1-vessel coronary disease (<35% stenosis in all nondilated segments) who underwent angioplasty. ETT was performed < or =2 weeks before follow-up angiography and IVUS imaging. Only patients without any abnormalities precluding an accurate reading of the ST segment during ETT were included. Restenosis was defined as a > or =50% diameter stenosis by QCA criteria and as a cross-sectional area narrowing of > or =75% by IVUS. The ETT was positive in 12 patients and restenosis was documented by QCA and IVUS in 38% and 48% of cases, respectively. Sensitivity, specificity, and positive and negative predictive values of ETT when QCA was used as a reference were 55%, 67%, 50%, and 71%, respectively. This corresponded to an accuracy of 62% when compared with QCA. Sensitivity, specificity, and positive and negative predictive values were 79%, 93%, 92%, and 82% when ETT was compared with IVUS, with an accuracy of 86% (p = 0.002). Thus, ETT is a reliable noninvasive method for detecting the presence of restenosis after PTCA in patients with 1-vessel coronary artery disease. The presence of > or =75% cross-sectional narrowing shown by IVUS is well correlated with > or =1-mm ST-segment depression at follow-up ETT after PTCA.     

Combined revascularization strategy for acute myocardial infarction in patients with intracoronary thrombus: preceding intracoronary thrombolysis and subsequent mechanical angioplasty

Thrombus in the infarct-related artery is one of the limitations for flow restoration in primary percutaneous transluminal coronary angioplasty (PTCA) treatment for acute myocardial infarction (AMI). The present study investigated the benefit of preceding intracoronary thrombolysis (ICT) by retrospectively analyzing acute phase flow restoration in 80 AMI patients with intracoronary thrombus: 40 undergoing primary PTCA alone (primary PTCA group) and 40 treated with preceding ICT plus PTCA (combined group). Acute phase Thrombolysis in Myocardial Infarction (TIMI) grade flow was as follows: TIMI 0/1: 35.0% vs 12.5% for the primary PTCA group and the combined group, p=0.06; TIMI 2: 7.5% vs 15.0%, p=NS; TIMI 3: 57.5% vs 72.5%, p=NS). In the subgroup analysis, it was also less in the combined group among 33 patients with a left anterior descending coronary artery (LAD) lesion (42.1 % vs 7.1%, p=0.08), but not among the remaining 47 with either a right coronary artery or left circumflex artery lesion. The combined therapy may potentially provide better acute phase flow restoration in AMI patients with an intracoronary thrombus in a LAD lesion.     

冠状动脉病变与肾动脉粥样硬化性狭窄

目的探讨动脉粥样硬化性肾动脉狭窄(ARAS)与脉压及其他相关因素的关系。方法553例入选病例在冠脉造影后行非选择性肾动脉造影,应用多变量Logistic回归分析评价脉压及其他临床因素和ARAS的关系。结果连续3年入选553例患者,24例(4.3%)有轻度肾血管病变(腔径狭窄<50%),84例(15.2%)ARAS(腔径狭窄≥50%),冠心病者ARAS(22.6%vs2.0%)及肾血管病变(5.9%vs1.5%)发生率明显高于非冠心病者。多因素Logistic逐步回归分析显示冠脉狭窄程度、脉压、血肌酐是ARAS发生的独立危险因素。结论ARAS与冠心病冠脉病变程度密切相关。脉压和血肌酐升高是ARAS的独立危险因素。     

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.