J Nucl Med. Markus Schwaiger István Kósa, Rudolf Blasini, Jan Schneider-Eicke, Franz J. Neumann, Ichiro Matsunari, Jodi Neverve, Albert Schömig and Implantation Myocardial Perfusion Scintigraphy to Evaluate Patients After Coronary Stent http://jnm.snmjournals.org/content/39/8/1307 This article and updated information are available at: http://jnm.snmjournals.org/site/subscriptions/online.xhtml Information about subscriptions to JNM can be found at: http://jnm.snmjournals.org/site/misc/permission.xhtml Information about reproducing figures, tables, or other portions of this article can be found online at:

CONTEXT:A higher mortality risk for women with acute myocardial infarction (AMI) is a common finding in studies that compare the postinfarction outcome of women vs men. It is not clear, however, whether sex is an independent predictor of death among patients systematically treated with aggressive reperfusion and medical strategies.OBJECTIVE:To assess the impact of patient's sex on outcome in a consecutive series of patients with AMI treated with a reperfusion strategy largely based on percutaneous coronary interventions.DESIGN, SETTING, AND PATIENTS:Inception cohort of 1937 patients (502 women and 1435 men) who were admitted with a diagnosis of AMI to a tertiary referral institution between January 1995 and December 2000.MAIN OUTCOME MEASURES:Mortality at 1 year after AMI.RESULTS:Compared with men, women were older (70 vs 61 years; P<.001) and had known diabetes or hypertension more often. Both men and women received essentially identical therapy with the majority of patients (86%) receiving reperfusion therapy via percutaneous coronary interventions. There were no significant differences in 1-year Kaplan-Meier death rates with 13.8% (68 cases) among women and 12.9% (184 cases) among men (unadjusted hazard ratio, 1.06; 95% confidence interval, 0.80-1.39; P =.70). After age adjustment, women had a lower risk of death (hazard ratio, 0.65; 95% confidence interval, 0.49-0.87; P =.004).CONCLUSION:Despite their more advanced age and greater prevalence of diabetes or hypertension, women with AMI who were treated with a reperfusion strategy largely based on percutaneous coronary interventions show a similar outcome as men.

BACKGROUND:Patients with acute myocardial infarction might benefit from the addition of glycoprotein IIb/IIIa inhibitors to fibrinolytic or mechanical reperfusion strategies. We compared two strategies, stenting and fibrinolysis, both combined with abciximab, in terms of their ability to salvage myocardium in patients with acute myocardial infarction.METHODS:We enrolled 162 patients with acute myocardial infarction within 12 h of onset of symptoms, assigning 81 stenting plus abciximab and 81 alteplase plus abciximab. Technetium-99m sestamibi scintigraphy was done at admission and after a median of 11 days to calculate initial perfusion defect, final infarct size, and degree of myocardial salvage. The primary endpoint was the salvage index (the ratio of the degree of myocardial salvage to the initial perfusion defect). Major adverse clinical events within 6 months from randomisation were also compared between the two treatments.FINDINGS:Paired scintigraphic measurements were available for 70 patients in the stent group and 71 in the alteplase group. Stenting was associated with greater myocardial salvage than alteplase (median 13.6% [IQR 5.9-23.9] vs 8.0% [2.5-16.0] of the left ventricle; p=0.007). Salvage index was greater in the stent group than in the alteplase group (median 0.60 [0.37-0.82] vs 0.41 [0.13-0.58]; p=0.001). The 6-month mortality rate was 5% (four deaths) in the stent group and 9% (seven deaths) in the alteplase group (relative risk 0.56 [95% CI 0.17-1.88]; p=0.35).INTERPRETATION:In patients with acute myocardial infarction, a reperfusion strategy based on stenting with abciximab produced more myocardial salvage than the combination of fibrinolysis plus abciximab. Larger studies are needed to assess whether these effects translate into clinical benefit.

Coronary stent implantation is being performed in an increasing number of patients with a wide spectrum of clinical and lesion characteristics. A variety of stent designs are now available and continuous efforts are being made to improve the stent placement procedure. The objective of this study was to perform a comprehensive analysis of the relation between clinical, lesion, and procedural factors, and restenosis after intracoronary stenting in a large and unselected population of patients. A consecutive series of 4,510 patients with coronary stent placement was analyzed. Exclusion criteria were only a failed procedure and an adverse outcome within the first month after the intervention. Follow-up angiography was performed in 80% of patients at 6 months. Clinical, lesion, and procedural data from all 3,370 patients (4,229 stented lesions) with follow-up angiography were analyzed in a logistic regression model for restenosis (> or =50% diameter stenosis). Clinical factors contributed to the predictive power of the model much less than lesion and procedural factors. The strongest risk factor for restenosis was a small vessel size, with a 79% increase in the risk for a vessel of 2.7 mm versus a vessel of 3.4 mm in diameter. Stent design was the second strongest factor; the incidence of restenosis ranged from 20.0% to 50.3% depending on the stent type implanted. In conclusion, this study demonstrates the predominant role of lesion and procedural factors in determining the occurrence of restenosis after coronary stent placement. Among these factors, stent design appears to play a particularly important role in the hyperplastic response of the vessel wall.

OBJECTIVES In the Intracoronary Stenting and Antithrombotic Regimen-2 trial (ISAR-2), we sought to investigate the effect of abciximab on angiographic and clinical restenosis after stenting following acute myocardial infarction (AMI). We also intended to assess the impact of abciximab on clinical outcome in this setting.BACKGROUND It is unclear whether abciximab reduces neointima formation after stenting. Such an effect may be particularly prominent in thrombus-containing lesions.METHODS Patients undergoing stenting within 48 h after onset of AMI were randomly assigned to receive either standard-dose heparin or abciximab plus reduced-dose heparin. Of 401 patients randomized, 366 without 30-day adverse events were eligible for six-month angiographic follow-up. Scheduled angiography was performed in 80% of these patients.RESULTS By 30 days, the composite clinical end point of death, reinfarction, and target lesion revascularization (TLR) was reached in 5.0% of the abciximab group and in 10.5% of the control group (p = 0.038). At one year, absolute reduction in the composite clinical end point by abciximab was still 5.7% but had lost its statistical significance. Our primary end point, late lumen loss, was 1.26 +/- 0.85 mm with abciximab and 1.21 +/- 0.74 mm with standard heparin (p = 0.61), and binary angiographic restenosis rates were 31.1% and 30.6%, respectively (p = 0.92).CONCLUSIONS In patients undergoing stenting following AMI, abciximab exerted beneficial effects by substantially reducing the 30-day rate of major adverse cardiac events. During one-year follow-up, there was no additional benefit from a reduction in TLR nor did abciximab reduce angiographic restenosis. (C) 2000 by the American College of Cardiology.

Background-The modified American College of Cardiology/American Heart Association (ACC/AHA) lesion morphology criteria are predictive of early outcome after various coronary catheter interventions. Their potential prognostic value after stent implantation and, in particular, for restenosis and long-term clinical outcome has not been studied. We assessed the prognostic value of the modified ACC/AHA criteria for the long-term angiographic and clinical outcome of patients after coronary stenting. Methods and Results-This study includes 2944 consecutive patients with symptomatic coronary artery disease treated with coronary stent placement. Modified ACC/AHA lesion morphology criteria were used to qualitatively assess the angiograms; type A and B1 lesions were categorized as simple, and type B2 and C lesions were designated complex. Primary end points were angiographic restenosis and 1-year event-free survival. Restenosis rate was 33.2% in complex lesions and 24.9% in simple lesions (P<0.001). It was 21. 7% for type A, 26.3% for type B1, 33.7% for type B2, and 32.6% for type C lesions. One-year event-free survival was 75.6% for patients with complex lesions and 81.1% for patients with simple lesions (P<0. 001). It was 85.2% for patients with type A, 79.4% for type B1, 75. 9% for type B2, and 75.2% type C lesions. The higher risk for restenosis and an adverse outcome associated with complex lesions was also maintained after multivariate adjustment for other clinical and angiographic characteristics. Conclusions-The modified ACC/AHA lesion morphology scheme has significant prognostic value for the outcome of patients after coronary stent placement. Lesion morphology is able to influence the restenosis process and thus the entire 1-year clinical course of these patients.

Venous myocardial contrast echocardiography is a new method for myocardial perfusion imaging. It has been shown to accurately evaluate risk area and infarct size in the experimental setting of acute myocardial infarction and has recently become clinically available. We used this method to assess myocardial salvage after coronary reperfusion in a patient with acute coronary syndrome.A 68-year-old man with known single-vessel coronary artery disease presented with 6 hours of moderate chest pain typical of unstable angina. Four years earlier, a percutaneous transluminal coronary angioplasty of the left anterior descending coronary artery had been performed; the patient was asymptomatic throughout …

OBJECTIVES The aim of this study was to quantitatively evaluate myocardial flow reserve in patients early after coronary stent implantation using positron emission tomography.BACKGROUND Delayed restoration of coronary flow reserve after percutaneous transluminal corollary angioplasty (PTCA) has been observed using a variety of techniques. Altered distal vasoregulation as well as residual stenosis have been considered possible explanations for this phenomenon. Although the implantation of stents may influence some of these mechanisms, little data are available characterizing coronary flow reserve early after stent placement.METHODS In 14 patients 1.6 +/- 0.6 days after stenting, N-13-ammonia positron emission tomographic studies were performed at rest and during adenosine-induced vasodilation. Myocardial blood flow was quantified using a three-compartment model. Rest and stress flow data, as well as coronary flow reserve of stented vascular territories, were compared with that of remote areas.RESULTS The stenosis decreased from 72.1 +/- 7.3% to 3.7 +/- 6.7% after stent implantation. Coronary flow in the stented areas did not differ significantly from that in remote areas either at rest (76.1 +/- 18.5 and 75.7 +/- 17.7 ml/min/100 g, respectively), or during maximal vasodilation (205.5 +/- 59.9 and 179.4 +/- 47.4 ml/min/100 g, respectively). In addition, there was no significant difference in the calculated values of coronary reserve of these two regions (2.74 +/- 0.64 and 2.43 +/- 0.55, respectively).CONCLUSIONS The mechanical support of dilated arteries by a stent not only restores the macroscopic integrity of epicardial arteries, but also results, in contrast to conventional PTCA procedures, in early recovery of flow reserve. (J Am Cell Cardiol 1999;34:1036-41) (C) 1999 by the American College of Cardiology.

BACKGROUND:High-pressure dilatation is considered a better stent placement strategy, but this has not yet been proved by appropriately designed studies. The objective of this randomized trial was to assess the role of high-pressure dilatation in the early and late outcome of patients undergoing coronary stent placement.METHODS AND RESULTS:Consecutive patients with coronary stent placement were randomly assigned to high- (15 to 20 atm, 468 patients) or low- (8 to 13 atm, 466 patients) balloon-pressure dilatation. The primary end point of the study was the event-free survival at 1 year. Secondary end points were the incidence of stent thrombosis at 30 days and angiographic restenosis (>/=50% diameter stenosis) at 6 months. The incidence of stent thrombosis was 1.7% in the high-pressure and 1.9% in the low-pressure group (relative risk 0.89; 95% CI 0.30 to 2.56). During the first 30 days, although there was no significant difference in the incidence of Q-wave myocardial infarction, the incidence of non-Q-wave infarction was 6.4% in the high-pressure and 3.4% in the low-pressure group (relative risk 1. 87; 95% CI 1.02 to 3.42). The restenosis rate was 30.4% in the high-pressure and 31.4% in the low-pressure group (relative risk 0. 97; 95% CI 0.75 to 1.26). Event-free survival at 1 year was not significantly different between the groups, with 78.8% in high-pressure patients and 75.5% in patients assigned to low-pressure dilatation (hazard ratio 0.85; 95% CI 0.65 to 1.11).CONCLUSIONS:The systematic use of high-balloon-pressure inflation (15 to 20 atm) during coronary stent placement is not associated with any significant influence on the 1-year outcome of patients undergoing this intervention.

BACKGROUNDApart from its established effects on vessel patency after percutaneous coronary revascularization, glycoprotein IIb/IIIa receptor blockade by abciximab may improve myocardial perfusion by inhibition of the interaction of platelets and platelet aggregates with the microvasculature. We investigated the effect of abciximab with stent placement in acute myocardial infarction.METHODS AND RESULTSIn a prospective randomized trial, patients undergoing stenting in acute myocardial infarction within 48 hours after onset of symptoms were randomly assigned to receive either standard-dose heparin or abciximab plus low-dose heparin. Immediately after the procedure and at 14-day angiographic follow-up, we assessed flow velocity in the recanalized vessel with the Doppler wire and regional wall motion by the centerline method. End points were changes in papaverine-induced peak flow velocities and in wall motion indices. We assigned 98 patients to standard heparin and 102 to abciximab. We obtained 152 paired flow measurements and 151 paired left ventricular function studies. Residual stenoses of the treated lesions did not differ between the 2 groups. Improvement of peak flow velocity (mean [95% CI]: 18.1 cm/s [13.6 to 22.6 cm/s], n=80, versus 10.4 cm/s [5.4 to 15.4 cm/s], n=72, P=0.024) and wall motion index (0.44 SD/chord [0.29 to 0.59 SD/chord], n=79 versus 0. 15 SD/chord [0.00 to 0.30 SD/chord], n=72, P=0.007) was significantly greater in patients assigned to abciximab than in those on heparin alone. At follow-up, the abciximab group had a higher global left ventricular ejection fraction than the heparin group (62% [59% to 65%] versus 56% [53% to 59%], P=0.003).CONCLUSIONSAbciximab had important effects beyond the maintenance of large-vessel patency. It improved the recovery of microvascular perfusion and concomitantly enhanced the recovery of contractile function in the area at risk.

This study was designed to test the hypothesis that patients fulfilling intravascular ultrasound (IVUS) criteria for optimal coronary stent implantation show a reduction in the restenosis rate at 6 months. IVUS guidance for stent dilation may be associated with facilitated stent implantation and an increased acute luminal gain, but it has not yet been determined, whether and to what extent this procedure is associated with a reduction in the restenosis rate. IVUS-guided optimization of Palmaz-Schatz stent placement was performed in 125 consecutive patients, 64 of whom fulfilled IVUS-criteria for optimal stent placement. Another 125 patients served as the non-IVUS control group. In 107 patients (86%) of the non-IVUS control group and 105 patients (84%) of the IVUS group, angiographic follow-up was performed. The IVUS group of patients revealed a significantly lower restenosis rate of 20.9% as compared with 29.9% in the control group (P = 0.033). Patients that met IVUS criteria for optimal stent placement had a larger minimal lumen diameter immediately after stent implantation (3.13 +/- 0.44 vs. 2.95 +/- 0.47 mm; P = 0.045) and at 6-month follow-up (2.23 +/- 0.78 vs. 1.87 +/- 0.76 mm; P = 0.019) as well as a significantly lower restenosis rate (13.5% vs. 28.3%; P = 0.038) as compared with patients that did not fulfil these criteria. Our data suggest that patients fulfilling IVUS criteria for optimal stent placement demonstrate a reduced risk for the development of restenosis. Thus, IVUS investigation identifies factors predictive of restenosis after coronary stent placement.

UNLABELLEDCoronary stent implantation is an increasingly accepted revascularization method. The 20%-30% restenosis rate during the first 6 mo requires a close follow-up of the patients. Since there is very little data available defining the role of perfusion scintigraphy in the management of this population, the aim of this study was to assess the diagnostic performance of stress myocardial perfusion imaging for detecting restenosis in patients after coronary stent implantation.METHODSIn 82 patients, 93 rest or stress SPECT studies were performed using 201Tl and 99mTc-hexakis-2-methoxyisobutyl isonitrile to evaluate 99 vascular territories with implanted coronary stents. The average interval between the stent implantation and the scintigraphic study was 210.5 +/- 129.6 days. The scintiscans were visually evaluated. A stress-induced perfusion defect with reversibility at rest was used as the criterion for stent restenosis.RESULTSCoronary angiography revealed a stenosis of > 50% diameter in the region of the stent in 19 arteries, while in 80 arteries there was no evidence of restenosis angiographically. With perfusion scintigraphy, 15/19 vascular territories with restenosed stents showed stress-induced perfusion abnormalities (sensitivity = 79%), while 62/80 territories without restenosis did not (specificity = 78%). In territories without a myocardial infarction (n = 48), sensitivity and specificity values were 8/8 (100%) and 36/44 (82%), and in territories with a myocardial infarction (n = 47) 7/11 (64%) and 26/36 (72%), respectively. Side branch stenosis was fairly frequent in patients without stent restenosis but with a reversible perfusion pattern on their scintiscan (8/18); however, these stenoses were induced infrequently by the stents (3 cases).CONCLUSIONUsing the criterion of defect reversibility, stress perfusion SPECT can accurately detect restenoses of coronary artery stents. This method is most accurate for evaluating patients without a previous myocardial infarction in the stented vascular territory.

OBJECTIVES:The Intracoronary Stenting and Antithrombotic Regimen (ISAR) trial is a randomized comparison of combined antiplatelet with anticoagulant therapy after coronary Palmaz-Schatz stent placement. The objective of this study was to compare early and late clinical and angiographic outcome in a subgroup of patients with stent placement for acute myocardial infarction. BACKGROUND:Stenting has become a treatment option for acute myocardial infarction, but it is not known which antithrombotic regimen is more adequate after stent implantation. METHODS:One hundred twenty-three patients with successful stenting after acute myocardial infarction were randomized to receive aspirin plus ticlopidine (n = 61) or intense anticoagulant therapy (n = 62). Six-month repeat angiography was performed in 101 (86.3%) eligible patients. RESULTS:During the first 30 days after stenting, patients with antiplatelet therapy had a significantly lower clinical event rate (3.3% vs. 21.0%, p = 0.005) and stent vessel occlusion rate (0% vs. 9.7%, p = 0.03) and a trend to fewer cardiac events (1.6% vs. 9.7%, p = 0.12). After 6 months, the survival rate free of recurrent myocardial infarction was higher in patients with antiplatelet therapy (100% vs. 90.3%, p = 0.03), and the rate of stent vessel occlusion was lower (1.6% vs. 14.5%, p = 0.02). Both groups had comparable restenosis rates (26.5% vs. 26.9%, p = 0.87). CONCLUSIONS:This study demonstrates that combined antiplatelet therapy after stent placement in patients with acute myocardial infarction is associated with an overall better clinical and angiographic outcome than anticoagulant therapy.