Effect of eptifibatide on angiographic complications during percutaneous coronary intervention in the IMPACT--(Integrilin to Minimize Platelet Aggregation and Coronary Thrombosis) II Trial.

We sought to determine whether eptifibatide reduces elevation of creatine kinase (CK)-MB isoenzyme release during coronary intervention by preventing angiographic complications, by minimizing the sequelae of angiographic complications once they occur, or by other mechanisms. In the Integrilin to Minimize Platelet Aggregation and Coronary Thrombosis trial, patients underwent coronary intervention during treatment with placebo versus the glycoprotein IIb/IIIa receptor inhibitor eptifibatide. Eptifibatide decreased ischemic complications at 24 hours and 30 days. CK-MB elevations and in-laboratory angiographic complications (including major dissection, distal embolization, residual thrombus, abrupt closure, residual stenosis >50%, and side branch occlusion) were prospectively recorded. The incidence of any angiographic complication was lower in eptifibatide-treated patients (33%) than in placebo-treated patients (38%, p = 0.019). For patients with angiographic complications, there was a trend toward a reduced incidence of any elevation in CK-MB in the first 24 hours (29%, 135/0.75 eptifibatide dose; 33%, 135/0.5 eptifibatide dose; 37%, placebo). Among patients without angiographic complications, there was a similar trend toward fewer abnormal CK-MB levels in patients receiving eptifibatide (17% and 18% in eptifibatide arms vs 21% placebo). Thus, eptifibatide reduces angiographically evident complications during coronary intervention, but this effect accounts for only 1/3 of the reduced frequency of CK-MB elevations observed with eptifibatide. When angiographic complications occur, eptifibatide reduces rates of subsequent CK-MB elevation, accounting for another 1/3 of the reduction in CK-MB elevations. Finally, eptifibatide reduces the incidence of periprocedural CK-MB elevations in patients without angiographically evident complications, accounting for 1/3 of eptifibatide's overall effect in reducing of CK-MB elevations in patients undergoing percutanous coronary intervention.

Rapid assessment of glycoprotein IIb/IIIa blockade with the platelet function analyzer (PFA-100) during percutaneous coronary intervention.

BACKGROUND: The platelet function analyzer PFA-100 (Dade Behring, Miami, Fla) evaluates platelet function by determining the time to occlusion of an aperture in a membrane coated with collagen and adenosine diphosphate or epinephrine as whole blood flows under shear stress conditions. Platelet aggregation causes aperture occlusion, and results are reported as closure time (CT). Interindividual variability is observed in the level of platelet inhibition achieved with use of the current abciximab dosing regimen (0.25-mg/kg bolus + 10-microg/min infusion for 12 hours). The relationships between specific levels of platelet inhibition and clinical efficacy and safety have not been fully established. METHODS AND RESULTS: We prospectively studied platelet function in 27 patients receiving abciximab during percutaneous coronary intervention. This evaluation included determinations of platelet-rich plasma aggregometry, receptor occupancy studies (D3 assay), and CT measurements at baseline and 10 minutes, 4 hours, 12 hours, and 24 hours after the bolus. All patients received abciximab, aspirin, and heparin; patients undergoing coronary stent implantation received aspirin and ticlopidine after the procedure. CT results were reported within 10 minutes after initiation of testing. For 96% of patients, CT was 300 seconds (maximum CT) immediately after abciximab bolus and remained so throughout the infusion. At 24 hours we observed variable recovery from platelet inhibition and in 72% of patients CT returned to normal (< or =130 seconds). CONCLUSIONS: Findings with the PFA-100 were similar to results observed with platelet aggregometry and receptor occupancy measurements. Most patients treated with abciximab exhibit normalized platelet function at 24 hours despite moderate levels of receptor occupancy, suggesting dissociation between occupancy and function.

Dose-finding, safety, and tolerability study of an oral platelet glycoprotein IIb/IIIa inhibitor, lotrafiban, in patients with coronary or cerebral atherosclerotic disease.

BACKGROUND: Antiplatelet therapy is the mainstay of the treatment and secondary prevention of cardiovascular and cerebrovascular ischemic events. We assessed the safety, tolerability, and pharmacodynamics of lotrafiban, an oral platelet glycoprotein IIb/IIIa inhibitor, as a secondary prevention strategy in patients with cerebrovascular or cardiovascular disease. METHODS AND RESULTS: Overall, 451 patients with a recent cardiovascular or cerebrovascular acute ischemic event were randomized in a double-blind fashion to 1 of 5 dosing regimens for 12 weeks: placebo or 5, 20, 50, or 100 mg lotrafiban, both twice daily with 300 to 325 mg/d aspirin. The primary end point was the incidence and tolerability of major and minor bleeding during treatment. Secondary end points included inhibition of platelet aggregation and clinical events. The placebo and lotrafiban 5-mg groups had similarly low rates of minor and major bleeding, but the 100-mg arm was terminated early because of excess major bleeding. Protocol-defined thrombocytopenia (<100 000 platelets/microL) occurred in 5 lotrafiban-treated patients (1.4%, 95% CI 0.2% to 2.7%) and 1 placebo patient (1.1%, 95% CI 0% to 3.1%). Three lotrafiban-treated patients had a nadir platelet count <20 000/microL (0.9%, 95% CI 0% to 1.8%). Lotrafiban produced dose-dependent inhibition of platelet aggregation; 5 mg lotrafiban did not differ significantly from placebo, whereas 100 mg inhibited aggregation by nearly 100%. CONCLUSIONS: -Lotrafiban provides dose-dependent platelet inhibition when administered to a range of patients with atherosclerosis. The level of platelet inhibition appears to correlate with bleeding risk and drug tolerability.

Timing of and risk factors for myocardial ischemic events after percutaneous coronary intervention (IMPACT-II). Integrilin to Minimize Platelet Aggregation and Coronary Thrombosis.

We studied both the time course and risk factors for adverse clinical events after percutaneous coronary intervention (PCI). Such information is critical to clinical decision-making, but scant quantitative data exist to describe the time course of these adverse outcomes. Patients enrolled in the Integrilin to Minimize Platelet Aggregation and Coronary Thrombosis-II (IMPACT-II) trial were analyzed. Patients undergoing elective, urgent, or emergency PCI (n = 4,010) were randomized to receive either placebo or 1 of 2 eptifibatide regimens during intervention. We evaluated the time to the primary end point of the trial, the 30-day composite of death, myocardial infarction, repeat nonelective PCI, nonelective bypass surgery, or stenting for abrupt closure. Adverse events occurred in 407 patients (10.1%). Because the risk of events declined substantially between 6 and 9 hours (66% occurred within 6 hours), events were classified as occurring before or after 6 hours. Independent predictors of "early" events included dissection, pre- and postprocedural coronary blood flow, side-branch occlusion, procedural thrombolytic use, previous bypass, presentation with unstable angina, absence of diabetes, and hyperlipidemia. The predictors of "late" events included lower weight, increased baseline heart rate, coronary dissection, and procedural thrombolytic use. The risk of ischemic events were greatest immediately after PCI and rapidly declined, so that by 9 hours the hazard function plot was flat; 66% of events occurred within 6 hours of PCI. Knowledge of the risk factors for early and late events help risk-stratify patients before and after intervention for myocardial ischemic events.

Clinical outcomes after detection of elevated cardiac enzymes in patients undergoing percutaneous intervention. IMPACT-II Investigators. Integrilin (eptifibatide) to Minimize Platelet Aggregation and Coronary Thrombosis-II.

OBJECTIVES: We examined the relations of elevated creatine kinase (CK) and its myocardial band isoenzyme (CK-MB) to clinical outcomes after percutaneous coronary intervention (PCI) in patients enrolled in Integrilin (eptifibatide) to Minimize Platelet Aggregation and Coronary Thrombosis-II (trial) (IMPACT-II), a trial of the platelet glycoprotein IIb/IIIa inhibitor eptifibatide. BACKGROUND: Elevation of cardiac enzymes often occurs after PCI, but its clinical implications are uncertain. METHODS: Patients undergoing elective, scheduled PCI for any indication were analyzed. Parallel analyses investigated CK (n=3,535) and CK-MB (n=2,341) levels after PCI (within 4 to 20 h). Clinical outcomes at 30 days and 6 months were stratified by postprocedure CK and CK-MB (multiple of the site's upper normal limit). RESULTS: Overall, 1,779 patients (76%) had no CK-MB elevation; CK-MB levels were elevated to 1 to 3 times the upper normal limit in 323 patients (13.8%), to 3 to 5 times normal in 84 (3.6%), to 5 to 10 times normal in 86 (3.7%), and to >10 times normal in 69 patients (2.9%). Elevated CK-MB was associated with an increased risk of death, reinfarction, or emergency revascularization at 30 days, and of death, reinfarction, or surgical revascularization at 6 months. Elevated total CK to above three times normal was less frequent, but its prognostic significance paralleled that seen for CK-MB. The degree of risk correlated with the rise in CK or CK-MB, even for patients with successful procedures not complicated by abrupt closure. CONCLUSIONS: Elevations in cardiac enzymes, including small increases (between one and three times normal) often not considered an infarction, are associated with an increased risk for short-term adverse clinical outcomes after successful or unsuccessful PCI.

Clinical risk factors for ischemic complications after percutaneous coronary interventions: results from the EPIC trial. The EPIC Investigators.

BACKGROUND: Most analyses of complications after percutaneous coronary intervention have been limited to angiographic predictors of abrupt closure. We sought to determine the relation between baseline clinical and angiographic characteristics and clinical ischemic events and whether treatment with the platelet glycoprotein IIb/IIIa receptor antagonist c7E3 reduced ischemic events differentially in patients with distinct lesion morphologic characteristics. In the EPIC trial, a bolus and infusion of c7E3 decreased the 30-day incidence of death, myocardial infarction, and need for revascularization by 35% in 2099 high-risk patients. METHODS: We used logistic regression modeling to determine the relations between these patients' baseline clinical and angiographic characteristics and the composite primary end point. We also constructed multivariable models with interaction terms to assess treatment effect on prespecified, core laboratory-assessed, coronary morphologic characteristics. RESULTS: The most important predictors of a poor outcome were low weight (chi-square = 10.5, P =.001) and preprocedural percent stenosis (chi-square = 15.0, P <.001). History of hypertension, nonwhite race, and peripheral vascular disease were also associated with an increased risk, as were all measures of lesion complexity except calcification and presence of a side branch. The treatment benefit with abciximab was significantly greater with less complex than with more complex lesion morphologic characteristics. CONCLUSIONS: Future risk models should include these baseline characteristics to define the risk for ischemic complications in individual patients, and treatment with abciximab should not be predicated on lesion morphologic findings alone.

Occurrence and clinical significance of thrombocytopenia in a population undergoing high-risk percutaneous coronary revascularization. Evaluation of c7E3 for the Prevention of Ischemic Complications (EPIC) Study Group.

OBJECTIVES: This study sought to determine the frequency of thrombocytopenia and its relation with clinical outcomes in high risk patients undergoing percutaneous coronary revascularization who received either the platelet glycoprotein (GP) IIb/IIIa receptor antagonist abciximab (ReoPro, c7E3 Fab) or conventional therapy. BACKGROUND: The development of thrombocytopenia on exposure to GPIIb/IIIa antagonists threatens the utility and economic viability of this drug class for patients with vascular disease. METHODS: We analyzed data from the Evaluation of c7E3 for the Prevention of Ischemic Complications trial (EPIC), a 2,099-patient, randomized trial of placebo, abciximab bolus or abciximab bolus plus a 12-h infusion during high-risk coronary revascularization. RESULTS: Thrombocytopenia (nadir platelet count <100 x 10(9)/ liter) developed in 81 patients (3.9%) during their hospital stay, with 19 (0.9%) developing severe (<50 x 10(9)/liter) thrombocytopenia. Both thrombocytopenia and severe thrombocytopenia were more frequent in the bolus-plus-infusion arm (5.2% and 1.6%, respectively) than in the bolus-only and placebo arms combined (p = 0.020 and p = 0.025, respectively). Acute profound thrombocytopenia developed in two patients in the bolus-plus-infusion arm. Patients with thrombocytopenia experienced more unfavorable clinical outcomes than those who did not develop thrombocytopenia, regardless of treatment assignment, but those with thrombocytopenia who received abciximab had fewer worse outcomes at 30 days. Multivariable logistic modeling revealed a lower baseline platelet count, older age and lighter weight to be important predictors of thrombocytopenia. In a logistic regression model, bolus-plus-infusion treatment was a significant predictor of thrombocytopenia (p = 0.016) and remained so after adjustment for procedures and baseline risk factors (p = 0.0077). CONCLUSIONS: Thrombocytopenia was associated with adverse clinical outcomes and excessive bleeding, but patients receiving abciximab fared better than those receiving placebo.

Modifiable risk factors for vascular access site complications in the IMPACT II Trial of angioplasty with versus without eptifibatide. Integrilin to Minimize Platelet Aggregation and Coronary Thrombosis.

OBJECTIVES: This study was designed to identify potential predictors of vascular access site (VAS) complications in the large-scale Integrilin to Minimize Platelet Aggregation and Coronary Thrombosis (IMPACT) II trial, which studied angioplasty with versus without a new glycoprotein (GP) IIb/IIIa receptor inhibitor (eptifibatide). BACKGROUND: GP IIb/IIIa receptor inhibition during coronary interventions has been associated with excess VAS complications. If other predictors of VAS complications could be identified, they might be manipulated to reduce complications. METHODS: A total of 4,010 patients undergoing percutaneous transluminal coronary revascularization (PTCR) were randomized into one of three bolus/20- to 24-h infusion arms: placebo bolus/placebo infusion; 135-microg/kg body weight eptifibatide bolus/0.5-microg/kg per min eptifibatide infusion; or 135-microg/kg eptifibatide bolus/0.75-microg/kg per min eptifibatide infusion. Heparin during the procedure was weight adjusted and stopped 4 h before sheaths were removed. Logistic regression modeling was used to identify independent predictors of VAS complications. RESULTS: VAS complications were more common in patients treated with eptifibatide (9.9% vs. 5.9% placebo-treated patients, p < 0.001). Multivariate analysis identified eptifibatide therapy (p < 0.0001), advanced age (p = 0.0001), longer time to sheath removal (p = 0.0002), stent placement (with intense post-stent anticoagulation) (p = 0.0004), female gender (p = 0.0006), PTCR within 24 h of thrombolytic therapy (p = 0.002), larger heparin doses during PTCR (p = 0.009), major coronary dissection (p = 0.03) and placement of a venous sheath (p = 0.04) as independent predictors of VAS complications. CONCLUSIONS: VAS complications may be reduced by early sheath removal, by avoiding placement of venous sheaths and by limiting heparin dosing to avoid excessive activated clotting times. Early sheath removal during inhibition of platelet aggregation by eptifibatide is feasible.

Clinical characteristics and long-term outcome of patients in whom congestive heart failure develops after thrombolytic therapy for acute myocardial infarction: development of a predictive model.

Ischemic heart disease is the most common cause of congestive heart failure, which often begins after acute myocardial infarction. To better delineate the clinical characteristics and outcomes of patients in whom congestive heart failure develops after acute myocardial infarction in the thrombolytic era, we prospectively evaluated patients enrolled in six of the TAMI trials. The study cohort comprised 1619 consecutive patients who had at least 1 mm of ST-segment elevation in two contiguous electrocardiographic leads within 6 hours of the onset of acute myocardial infarction and who received intravenous thrombolytic therapy. We prospectively collected clinical characteristics, baseline demographics, acute and 1-week angiographic variables, and in-hospital and 1-year outcome data. We performed stepwise multivariable regression analysis to determine the noninvasive and invasive predictors of the development of in-hospital congestive heart failure. Congestive heart failure developed in 301 patients in the hospital (19% of 1521 patients admitted were not in heart failure). These patients were likely to be older and female, have diabetes mellitus and previous myocardial infarction, and have an anterior wall myocardial infarction. On acute angiography, they had lower ejection fractions and a higher incidence of multivessel disease. Patency at 90 minutes was lower in the patients with congestive heart failure, and acute mitral regurgitation occurred in 1.6% versus 0.21% of patients without congestive heart failure. Patients with congestive heart failure had higher mortality, more in-hospital complications, and longer hospitalizations. At 1-year follow up, 21% of the patients in whom congestive heart failure developed had died versus 5% in the group without congestive heart failure. Predictors of new congestive heart failure included increased age, anterior wall myocardial infarction, lower pulse pressure and systolic blood pressure, diabetes mellitus, and the presence of rales on admission. The acute angiographic variables of reduced ejection fraction, increased number of diseased vessels, and attempted percutaneous intervention improved the concordance of the predictive model by 6%. Congestive heart failure remains a common clinical problem after acute myocardial infarction and is associated with a twofold increase in in-hospital morbidity and a fourfold increase in in-hospital and 1-year mortality. The development of congestive heart failure in the hospital can be predicted from noninvasive and invasive baseline characteristics. We present a simple table to predict congestive heart failure from baseline characteristics and invasive information.

Combined accelerated tissue-plasminogen activator and platelet glycoprotein IIb/IIIa integrin receptor blockade with Integrilin in acute myocardial infarction. Results of a randomized, placebo-controlled, dose-ranging trial. IMPACT-AMI Investigators.

BACKGROUND: Platelet activation and aggregation may be key components of thrombolytic failure to restore and maintain perfusion in acute myocardial infarction. We performed a placebo-controlled, dose-ranging trial of Integrilin, a potent inhibitor of platelet aggregation, with heparin, aspirin, and accelerated alteplase. METHODS AND RESULTS: We assigned 132 patients in a 2:1 ratio to receive a bolus and continuous infusion of one of six Integrilin doses or placebo. Another 48 patients were randomized in a 3:1, double-blind fashion to receive the highest Integrilin dose from the first phase or placebo. All patients received accelerated alteplase, aspirin, and intravenous heparin infusion; all but two groups also received an intravenous heparin bolus. The highest Integrilin dose group from the nonrandomized phase and the randomized patients were pooled for analysis and compared with placebo-treated patients. The primary end point was Thrombolysis in Myocardial Infarction (TIMI) grade 3 flow at 90-minute angiography. Secondary end points were time to ST-segment recovery, an in-hospital composite (death, reinfarction, stroke, revascularization procedures, new heart failure, or pulmonary edema), and bleeding variables. The highest Integrilin dose groups had more complete reperfusion (TIMI grade 3 flow, 66% versus 39% for placebo-treated patients; P = .006) and a shorter median time to ST-segment recovery (65 versus 116 minutes for placebo; P = .05). The groups had similar rates of the composite end point (43% versus 42% for placebo-treated patients) and severe bleeding (4% versus 5%, respectively). CONCLUSIONS: The incidence and speed of reperfusion can be enhanced when a potent inhibitor of the glycoprotein IIb/IIIa integrin receptor, such as Integrilin, is combined with accelerated alteplase, aspirin, and intravenous heparin.

Immediate and reversible platelet inhibition after intravenous administration of a peptide glycoprotein IIb/IIIa inhibitor during percutaneous coronary intervention.

We studied the pharmacokinetic and pharmacodynamic properties of integrelin, a novel platelet glycoprotein IIb/IIIa receptor inhibitor, in patients undergoing elective percutaneous coronary intervention. Patients were randomized to placebo (n = 19) or to 1 of 4 integrelin dosing regimens (total n = 54) that were studied sequentially. All patients received aspirin and heparin. Patients were followed until discharge for the occurrence of adverse clinical events: death, myocardial infarction, coronary artery bypass surgery, repeat intervention, or recurrent ischemia. Bleeding was the primary safety end point. Frequent blood sampling was performed for adenosine diphosphate-induced platelet aggregations. Simplate bleeding times were performed. Adverse clinical events occurred less often in the integrelin-treated patients, although the overall numbers were too small to make a definitive statement as to clinical efficacy. There was no significant increase in serious bleeding among integrelin-treated patients. The 2 highest integrelin boluses (180 and 135 micrograms/kg) immediately (15 minutes after the bolus) provided > 80% inhibition of adenosine diphosphate-induced platelet aggregation in > 75% of treated patients. A constant integrelin infusion of 0.75 micrograms/kg/min maintained this marked antiplatelet effect, whereas an infusion of 0.50 micrograms/kg/min allowed gradual recovery of platelet function. Elective coronary intervention was performed safely and with no significant increase in serious bleeding events using integrelin with aspirin and heparin as an antithrombotic regimen. Integrelin provided rapid, intense, and persistent ex vivo platelet inhibition during coronary intervention. This new antiplatelet agent may be beneficial in reducing platelet-mediated ischemic complications of percutaneous coronary intervention.

Creatine kinase MM and MB isoforms in patients receiving thrombolytic therapy and acute angiography. TAMI Study Group.

Creatine kinase isoforms markers, including MB2 concentration, MB2/MB1 and MM3/MM1 ratios, and MT index (based on the "tissue" M subunits), were measured in serial specimens from 207 patients receiving thrombolytic therapy followed by acute angiography. The slope of release showed a significant relation (P < 0.05) between MB2 concentrations and patency, graded as TIMI 0 through TIMI 3; with regard to the precatheterization/baseline ratio, the MB2 concentrations, the MM3/MM1 ratio, and the MT index were all significantly related to graded patency (P < 0.004). Patients having patency graded as either TIMI 2/3 (Open) or TIMI 0/1 (Closed) showed highly significant differences (P < 0.03) in the slope of release and precatheterization/baseline ratio for all markers except the MB2/MB1 ratio. Defining Open as TIMI 3 and Closed as TIMI 0/1/2 showed very similar results. Despite these significant differences between the Open and Closed groups after thrombolytic therapy, none of the C index calculations (areas under ROC curves) for any of the isoform markers--either alone or combined--exceeded 0.70, suggesting that these markers have limited diagnostic utility for assessing patency.

Significance of a coronary artery with thrombolysis in myocardial infarction grade 2 flow "patency" (outcome in the thrombolysis and angioplasty in myocardial infarction trials). Thrombolysis and Angioplasty in Myocardial Infarction Study Group.

To determine whether pharmacologic reperfusion to Thrombolysis in Myocardial Infarction (TIMI) grade 2 flow during acute myocardial infarction confers the same clinical benefit as restoration of TIMI 3 flow, in-hospital clinical and angiographic outcomes in 1,229 patients prospectively enrolled in the Thrombolysis and Angioplasty in Myocardial Infarction trials were analyzed. Patients were treated with intravenous tissue plasminogen activator or urokinase, or both. Angiography of the infarct-related artery 90 minutes after initiation of thrombolytic therapy demonstrated TIMI grades 0, 1, 2, or 3 flow in 20%, 7%, 17%, and 55% of vessels, respectively. Rescue or adjunctive coronary angioplasty was performed in 80%, 27%, and 16% of patients with TIMI 0/1, 2, or 3 flow, respectively. Predischarge angiography was performed in 963 patients. A significant gradient of increasing mortality was seen in patients with lower TIMI flow (4.3%, 6.1%, and 10.1% with TIMI 3, 2, and 0/1 flow, respectively, p = 0.002). The incidence of congestive heart failure and recurrent ischemia was significantly higher in patients with TIMI 2 than with TIMI 3 perfusion (26% vs 19% for heart failure, p = 0.03; 23% vs 17% for recurrent ischemia, p = 0.05). Acute left ventricular ejection fraction and infarct zone regional wall motion were also significantly improved in patients with TIMI 3 than with TIMI 2 flow, with trends toward better improvement in global and regional function in the TIMI 3 group. These findings were not affected by the use of acute coronary angioplasty.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of platelet glycoprotein IIb/IIIa integrin blockade on activated clotting time during percutaneous transluminal coronary angioplasty or directional atherectomy (the EPIC trial). Evaluation of c7E3 Fab in the Prevention of Ischemic Complications trial.

The activated clotting time (ACT) has been used during percutaneous transluminal coronary angioplasty (PTCA) to monitor the extent of thrombin inhibition and anti-coagulation from heparin in an attempt to minimize untoward thrombotic events and hemorrhagic complications. With the introduction of potent platelet inhibitors, such as the chimeric monoclonal antibody c7E3, to interventional cardiology, the utility of measuring and regulating procedural ACT has not been examined. To investigate the possible influence of platelet IIb/IIIa antagonism on procedural ACT, we reviewed data from the Evaluation of c7E3 Fab in the Prevention of Ischemic Complications (EPIC) trial. In the EPIC trial, 2,099 patients undergoing PTCA with a high risk of abrupt vessel closure were randomized to receive placebo (n = 696) or the IIb/IIIa platelet receptor antagonist c7E3 Fab (n = 1,403). Despite receiving less procedural heparin, and fewer patients receiving very high heparin doses (> 14,000 U) than the placebo group, those receiving c7E3 had a higher mean (401 vs 367 seconds, p < 0.001) ACT when corrected for body weight. The ACT is increased approximately 35 seconds by the platelet IIb/IIIa receptor antagonist c7E3 Fab. This has important implications for dosing conjunctive heparin therapy and performing PTCA or directional coronary atherectomy in the setting of IIb/IIIa-directed therapy.

Transformation of measurements percentage of white coat color for Holsteins and estimation of heritability.

Percentage of white coat color was measured on registration certificates of 4293 Holstein heifers on eight dairy farms in Florida. Measurements of white percentage were by visual evaluation on one side of the upper body (head, neck, and trunk) only and obtained in increments of 5%. Mean, median, mode, standard deviation, and skewness of white percentage were 25.6, 15, 0, 26.9, and 1.03. Distribution of white percentages showed lack of normality. Original data were transformed using an extension of the Box-Cox transformation to approach normality and to provide maximum likelihood estimators of the transformed parameters. Heritability estimates for percentages of white coat color were computed using derivative-free REML with an animal model. Estimates of heritability were .715 from untransformed data and .779 for transformed. Standard errors of estimates were slightly lower (.032 vs. .035) following transformation. Additional study to find an improved transformation procedure still seems warranted.

Clinical importance of thrombocytopenia occurring in the hospital phase after administration of thrombolytic therapy for acute myocardial infarction. The Thrombolysis and Angioplasty in Myocardial Infarction Study Group.

OBJECTIVES: The purpose of this study was to examine the incidence and clinical implications of thrombocytopenia that occurs in hospital after administration of thrombolytic therapy for acute myocardial infarction. BACKGROUND: The use of thrombolytic therapy in patients with acute myocardial infarction has improved mortaltiy rates, but hemorrhage remains a major complication. Because thrombocytopenia may be associated with hemorrhage after thrombolytic therapy, we examined the incidence and clinical implications of thrombocytopenia after administration of thrombolytic therapy for acute myocardial infarction. METHODS: The patient population comprised 1,001 patients enrolled in Phases 2, 3 and 5 of the Thrombolysis and Angioplasty in Myocardial Infarction (TAMI) trial and the urokinase trial. Patients received recombinant tissue-type plasminogen activator, urokinase or combination therapy in various dosing schemes. All patients received heparin, aspirin and a calcium-channel blocking agent. Thrombocytopenia occurring anytime after thrombolytic therapy was defined as a nadir platelet count either < 100,000/microliters or < 1/2 baseline. Blood loss was quantified by a bleeding index. Multiple logistic regression was used to evaluate the independent contribution of thrombocytopenia in a model predicting in-hospital mortality. RESULTS: Thrombocytopenia occurred in 16.4% of patients, with no difference among the thrombolytic regimens. Patients with thrombocytopenia had a lower median acute ejection fraction and a higher likelihood of three-vessel coronary artery disease than patients without thrombocytopenia. Patients with thrombocytopenia had more hemorrhage, a higher in-hospital mortality rate and a more complicated hospital course than patients without thrombocytopenia, even after consideration of other important variables, including age, acute ejection fraction, number of diseased vessels, bypass surgery and use of intraaortic balloon counterpulsation. CONCLUSIONS: Thrombocytopenia after thrombolytic therapy is a common event and is associated with excess hemorrhage and mortality. Platelet counts should be monitored daily after administration of thrombolytic therapy because the appearance of thrombocytopenia identifies a subset of patients at increased risk for hemorrhage and death.

Thrombolytic therapy for women with myocardial infarction: is there a gender gap? Thrombolysis and Angioplasty in Myocardial Infarction Study Group.

OBJECTIVES: The goal of this study was to investigate whether female gender portends an adverse prognosis independent of the severity of the underlying disease after acute myocardial infarction treated by thrombolysis. A total of 348 women were compared with 1,271 men enrolled in the Thrombolysis and Angioplasty in Myocardial Infarction (TAMI) trials. BACKGROUND: The reasons for gender differences in the management and prognosis of acute coronary artery syndromes remain poorly defined. The extent to which gender itself explains observed differences in outcome and use of diagnostic procedures remains unclear because confounding factors have not been specified. METHODS: Patients < 76 years of age presenting within 6 h of onset of ischemic symptoms with electrocardiographic ST segment elevation and without contraindications to thrombolysis, previous infarction in the same distribution or cardiogenic shock were prospectively enrolled in Phases 1 to 3, 5 and 7 of the TAMI trials. All patients received recombinant tissue-type plasminogen activator, urokinase or a combination of both agents. Protocol-mandated cardiac catheterization was performed during the hospital period. Rescue coronary angioplasty was carried out for reperfusion failure at angiography 90 min after initiation of thrombolytic therapy. Coronary artery bypass grafting or coronary angioplasty was performed for clinical indications. RESULTS: Women were older than men (61.0 +/- 9.7 vs. 55.8 +/- 10.1 years, mean +/- SD) and had a higher incidence of many risk factors for adverse outcome after myocardial infarction. There were no differences in baseline hemodynamic variables or time to thrombolytic treatment. Rates of acute and predischarge infarct-related artery patency and global and regional left ventricular function were similar in the two groups. Rates of in-hospital coronary angioplasty (52.6% and 54.1%) and bypass graft surgery (20.4% and 22.0%) were comparable in women and men, respectively. Women had higher unadjusted rates of mortality (9.2% vs. 5.4%, p = 0.014), reinfarction (6.4% vs. 2.6%, p = 0.005) and hemorrhagic stroke (2.0% vs. 0.55%, p = 0.017) than did men during the hospital period. When adjusted for clinical and angiographic variables, differences in mortality and hemorrhagic stroke did not reach statistical significance, and the risk of reinfarction was only marginally associated with gender. CONCLUSIONS: In selected patients undergoing thrombolytic therapy and cardiac catheterization for acute myocardial infarction, adjusted mortality rates and utilization of postlysis revascularization are similar in women and men. However, women may be at increased risk for reinfarction.

An analysis of the cause of early mortality after administration of thrombolytic therapy. The Thrombolysis Angioplasty in Myocardial Infarction Study Group.

BACKGROUND: The use of thrombolytic therapy in myocardial infarction has been associated with a considerable improvement in survival rate; however, almost 40% of the deaths during hospitalization occur during the first 24 h. Clinical and angiographic characteristics identified through careful comparison of those patients who die early with those who survive may serve as important targets for the development of new strategies for the management of myocardial infarction. METHODS: Medical records and autopsy reports of 810 patients enrolled into four sequential studies evaluating thrombolytic therapy and angioplasty in acute myocardial infarction were reviewed. All patients were enrolled into four similar protocols with administration of thrombolytic therapy (intravenous tissue plasminogen activator in 561 patients, urokinase in 102, and a combination of tissue plasminogen activator and urokinase in 147) and acute cardiac catheterization performed 90 min after starting therapy. RESULTS: The overall in-hospital mortality rate was 6.8% (55 out of 810), with 21 of these deaths (38%) occurring within the first day. The median (25th, 75th percentile) time to death was 3 (0, 12) days. Infarct location was more frequently anterior in patients who died within the first day. Patients who died 24 h after admission to hospital had the lowest patency rate (45%) compared with patients who died within 24 h (59%) and those who survived (71%, P = 0.003). The deaths within the first day were more likely to be a result of cardiogenic shock (48%), ventricular arrhythmias (14%), or cardiac rupture (9%), whereas late deaths were more likely to be a result of recurrent ischemia or reinfarction (32%) and non-cardiac causes (18%). Two patients had an intracranial hemorrhage within the first 24 h which caused immediate death in one and death on the third day of hospitalization in the other. CONCLUSION: Mortality within the first 24 h of thrombolytic therapy administration can be defined by inadequate myocardial reperfusion in patients with cardiac failure, possibly associated reperfusion injury leading to cardiac rupture, and an increased risk of intracranial hemorrhage. These factors may serve as targets for the development of new treatment strategies in acute myocardial infarction that may alter prognosis.

Noninvasive detection of reperfusion after thrombolysis based on serum creatine kinase MB changes and clinical variables. TAMI 7 Study Group. Thrombolysis and Angioplasty in Myocardial Infarction.

Coronary artery patency after thrombolytic therapy has important prognostic implications for survival after acute myocardial infarction. The ability to noninvasively identify patients early after thrombolysis may therefore allow other strategies, such as adjunctive therapy or rescue angioplasty, to be used to restore patency of the infarct-related artery. This study examined the use of a rapid creatine kinase (CK)-MB assay in conjunction with selected clinical variables for noninvasive detection of reperfusion after thrombolysis. Patients were enrolled in a study evaluating accelerated plasminogen activator dose regimens with patency assessments by first angiographic injection during acute angiography at a median and interquartile range (25th and 75th percentiles) 142 (96,195) minutes after starting thrombolytic therapy. Serum CK-MB samples measured by a rapid dual monoclonal antibody assay were obtained in 207 patients before (baseline) and 30 minutes, 90 minutes, and 3 hours after starting thrombolytic therapy. In 109 patients a CK-MB sample was obtained within 10 minutes of acute angiography (angio sample). At acute angiography the infarct-related artery was patent (Thrombolysis in Myocardial Infarction trial grade 2 to 3 flow) in 71%. Baseline CK-MB values were similar in patients with and without later reperfusion at acute angiography: 3 (0,8) ng/ml and 0 (0,4) ng/ml, respectively. At acute angiography, patients with successful reperfusion had higher CK-MB values [46 (20,138) ng/ml] compared with patients with persistent occlusion of the infarct-related artery [8 (3,63) ng/ml; p = 0.002).(ABSTRACT TRUNCATED AT 250 WORDS)

Continuous 12-lead ST-segment recovery analysis in the TAMI 7 study. Performance of a noninvasive method for real-time detection of failed myocardial reperfusion.

BACKGROUND: If a practical, reliable, noninvasive marker of failed reperfusion was available in real time, the benefits of further therapy in this patient subgroup could be tested. We developed a method of 12-lead ST-segment recovery analysis using continuously updated reference points to provide such a marker. METHODS AND RESULTS: In this study, our method was prospectively tested in 144 patients given thrombolytic therapy early in myocardial infarction. All patients had 12-lead continuous ST-segment monitoring and acute angiography, each analyzed in an independent, blinded core laboratory. ST-segment recovery and re-elevation were analyzed up to the moment of angiography, at which time patency was predicted. Predictions were correlated to angiographic infarct artery flow, with TIMI flow 0 to 1 as occluded and TIMI flow 2 to 3 as patent. Infarct artery occlusion was seen on first injection in 27% of patients. The positive predictive value of incomplete ST recovery or ST re-elevation by our method was 71%, negative predictive value 87%, with 90% specificity and 64% sensitivity for coronary occlusion. ST recovery analysis predicted patency in 94% of patients with TIMI 3 flow versus 81% of patients with TIMI 2 flow and predicted occlusion in 57% of patients with collateralized occlusion versus 72% of patients with non-collateralized occlusion. In a regression model including other noninvasive clinical descriptors, ST recovery alone contained the vast majority of predictive information about patency. CONCLUSIONS: In a blinded, prospective, angiographically correlated study design, 12-lead continuous ST-segment recovery analysis shows promise as a practical noninvasive marker of failed reperfusion that may contribute substantially to currently available bedside assessment. Our data also suggest that patients with TIMI 2 flow or with collateralized occlusions may represent a physiological spectrum definable with ST-segment recovery analysis.