Faculty Bibliography

BACKGROUND: Direct factor (F)Xa inhibition is an attractive method to limit thrombotic complications during percutaneous coronary intervention (PCI). OBJECTIVES: To investigate drug levels achieved, effect on coagulation markers, and preliminary efficacy and safety of several doses of DX-9065a, an intravenous, small molecule, direct, reversible FXa inhibitor during PCI. PATIENTS AND METHODS: Patients undergoing elective, native-vessel PCI (n = 175) were randomized 4 : 1 to open-label DX-9065a or heparin in one of four sequential stages. DX-9065a regimens in stages I-III were designed to achieve concentrations of > 100 ng mL-1, > 75 ng mL-1, and > 150 ng mL-1. Stage IV used the stage III regimen but included patients recently given heparin. RESULTS: At 15 min median (minimum) DX-9065a plasma levels were 192 (176), 122 (117), 334 (221), and 429 (231) ng mL-1 in stages I-IV, respectively. Median whole-blood international normalized ratios (INRs) were 2.6 (interquartile range 2.5, 2.7), 1.9 (1.8, 2.0), 3.2 (3.0, 4.1), and 3.8 (3.4, 4.6), and anti-FXa levels were 0.36 (0.32, 0.38), 0.33 (0.26, 0.39), 0.45 (0.41, 0.51), and 0.62 (0.52, 0.65) U mL-1, respectively. Stage II enrollment was stopped (n = 7) after one serious thrombotic event. Ischemic and bleeding events were rare and, in this small population, showed no clear relation to DX-9065a dose. CONCLUSIONS: Elective PCI is feasible using a direct FXa inhibitor for anticoagulation. Predictable plasma drug levels can be rapidly obtained with double-bolus and infusion DX-9065a dosing. Monitoring of DX-9065a may be possible using whole-blood INR. Direct FXa inhibition is a novel and potentially promising approach to anticoagulation during PCI that deserves further study

BACKGROUND: We evaluated whether the use of glycoprotein IIb/IIIa receptor inhibitors, in addition to heparin and aspirin, imparts an incremental benefit in a subgroup of patients with acute coronary syndromes (ACS) who had congestive heart failure (CHF) symptoms at presentation. METHODS: We analyzed patients enrolled in the Platelet IIb/IIIa in Unstable Angina: Receptor Suppression Using Integrilin Therapy (PURSUIT) trial, a randomized, double-blind, placebo-controlled study evaluating the use of eptifibatide versus placebo for patients with ACS without persistent ST-elevation. We compared the clinical characteristics and 30-day outcomes for 861 patients who had Killip class II or III CHF symptoms with those of 8558 patients who had no CHF symptoms. RESULTS: Odds ratios for the primary end point, 30-day death or non-fatal myocardial infarction, in the placebo group versus the eptifibatide group were similar for patients with and without CHF (odds ratio, 1.11; 95% CI, 0.8-1.5; odds ratio, 1.13; 95% CI, 1.0-1.3). However, adverse events were almost twice as frequent for patients with CHF compared with patients with no CHF (24.5% vs 14%). CONCLUSIONS: Although patients with non-ST-segment elevation ACS who have CHF have markedly worse outcomes than patients without CHF symptoms, we did not find an incremental benefit from the use of eptifibatide in this seriously ill subgroup

BACKGROUND: Direct angioplasty (PTCA) and thrombolytic therapy are the chief therapies for treating an ST-segment elevation myocardial infarction (MI). OBJECTIVE: This study was designed to evaluate sex differences in the relative benefit of direct PTCA versus thrombolytic therapy among patients enrolled in the Global Use of Strategies to Open Occluded Arteries in Acute Coronary Syndromes Angioplasty (GUSTO II-B PTCA) Substudy. METHODS: Women and men presenting with an acute ST-segment elevation MI were randomized to receive either direct PTCA or accelerated tissue plasminogen activator (t-PA). Patients were then randomized to treatment with either heparin or bivalirudin. A gender analysis of outcome was performed. RESULTS: Women were older than men (68.6 +/- 11.5 vs 59.5 +/- 12.0 years, P <.001) and were more likely to have diabetes (22.5% vs 13.5%, P <.0001) and hypertension (53.3% vs 34.8%, P =.001). After adjusting for differences in baseline variables, the odds ratio (OR) for reaching a 30-day clinical end point (death, nonfatal infarction, or nonfatal disabling stroke) was similar for women and men (1.35, 95% CI 0.88-2.08). The OR for reaching a clinical end point at 30 days for the PTCA-treated women compared with the t-PA-treated women was 0.685 (95% CI 0.36-1.32) and similar to the OR in men, 0.565 (95% CI 0.35-0.91), P for interaction =.535. Because women had a higher event rate than men, the absolute number of major events prevented when treating women with direct PTCA was higher than men (56 events/1000 women treated with PTCA vs 42 events per 1000 men treated with PTCA). CONCLUSIONS: Although the relative benefit of direct PTCA to t-PA for the treatment of an acute MI appears to be similar in women and men, women may derive a larger absolute benefit from direct PTCA

BACKGROUND: The enhancement of diastolic coronary blood flow by the combination of thrombolytic therapy (TT) and intra-aortic balloon counterpulsation (IABP) in experimental studies provides a rationale for their combined use in acute myocardial infarction (MI) complicated by cardiogenic shock. We examined the relation between TT (with and without IABP) and 12-month survival in the SHould We Emergently Revascularize Occluded Coronaries for Cardiogenic ShocK (SHOCK) Trial. METHODS AND RESULTS: Among 302 patients with myocardial infarction and cardiogenic shock who were randomized in the SHOCK Trial, 16 had absolute contraindications to TT. Among 150 patients randomly assigned to initial medical stabilization (IMS), 63% received TT, as recommended per protocol, compared with 49% of 152 patients randomly assigned to emergency revascularization, in whom TT was not recommended if immediate angiography was available. IABP deployment, which was protocol-recommended, was used in 86% of patients. The rate of severe bleeding was similar in patients receiving TT and in those not receiving TT (31% vs 26%, P =.37). Among patients randomly assigned to IMS, TT was associated with improved 12-month survival (unadjusted mortality hazard ratio, 0.59; P =.01; mortality hazard ratio adjusted for age and prior MI, 0.62; P =.02). TT was not associated with improved 12-month survival among patients randomly assigned to emergency revascularization (unadjusted mortality hazard ratio, 0.93; P =.76; mortality hazard ratio adjusted for age and prior MI, 1.06, P =.81). The test for interaction of TT and randomization group P value was.16, and there was insufficient statistical power to demonstrate a differential effect of TT on 12-month survival by treatment group assignment. CONCLUSIONS: Among patients randomly assigned to IMS in the SHOCK Trial, TT was associated with improved 12-month survival and did not significantly increase the risk of severe bleeding

OBJECTIVES: We examined the clinical, angiographic, and procedural characteristics determining survival after percutaneous coronary intervention (PCI) for cardiogenic shock. BACKGROUND: The SHOCK (SHould we emergently revascularize Occluded coronaries for Cardiogenic shocK?) trial prospectively enrolled patients with shock complicating acute myocardial infarction (MI). Patients were randomized to a strategy of early revascularization or initial medical stabilization. METHODS: Patients randomized to early revascularization underwent PCI or bypass surgery on the basis of predefined clinical criteria. Patients randomized to early revascularization who underwent PCI and had angiographic films available for analysis are the subject of this report (n = 82). RESULTS: The median time from MI to PCI was 11 h. The majority of patients had occluded culprit arteries (Thrombolysis In Myocardial Infarction [TIMI] grade 0 or 1 flow in 62%) and multivessel disease (81%). One-year mortality in PCI patients was 50%. Mortality was 39% if PCI was successful but 85% if unsuccessful (p < 0.001). Mortality was 38% if TIMI flow grade 3 was achieved, 55% with TIMI grade 2 flow, and 100% with TIMI grade 0 or 1 flow (p < 0.001). Mortality was 67% if severe mitral regurgitation was documented. Independent correlates of mortality were as follows: increasing age (p < 0.001), lower systolic blood pressure (p = 0.009), increasing time from randomization to PCI (p = 0.019), lower post-PCI TIMI flow (0/1 vs. 2/3) (p < 0.001), and multivessel PCI (p = 0.040). CONCLUSIONS: Restoration of coronary blood flow is a major predictor of survival in cardiogenic shock. Benefit appears to extend beyond the generally accepted 12-h post-infarction window. Surgery should be considered in shock patients with severe mitral insufficiency or multivessel disease not amenable to relatively complete percutaneous revascularization

OBJECTIVES: The goal of this study was to describe the core laboratory angiographic findings of 'SHould we emergently revascularize Occluded Coronaries for cardiogenic shocK' (SHOCK) trial participants and to determine the relationship of angiographic parameters to one-year survival. BACKGROUND: In the SHOCK trial, emergency revascularization improved one-year survival of patients with cardiogenic shock compared with initial medical stabilization including thrombolysis and intraaortic balloon counterpulsation. METHODS: Coronary angiography was performed by protocol in 147 of 152 (97%) patients in the emergency revascularization (ERV) group and by clinical selection in 100 of 150 (67%) patients in the initial medical stabilization (IMS) group. Of the other 50 IMS patients, 45 of 50 (90%) died rapidly and did not undergo angiography. RESULTS: Left ventricular ejection fraction was correlated with one-year survival in both treatment groups (p < 0.001). In the IMS group, the hazard ratio for death was 2.59 (95% confidence interval 1.47 to 4.58, p = 0.001) per diseased vessel (0/1 vs. 2 vs. 3). In the ERV group, the hazard ratio for death per diseased vessel was 1.11 (95% confidence interval 0.79 to 1.56, p = 0.559). Multivariate analysis of the angiography cohort (without regard for left ventriculogram measurements) identified initial Thrombolysis in Myocardial Infarction flow grade (p = 0.032), number of diseased vessels (for IMS patients only, p = 0.024), and culprit vessel (p = 0.004) as independent correlates of one-year survival, even after adjustment for key clinical factors. In the smaller cohort with left ventricular ejection fraction measured (n = 97), ejection fraction and culprit vessel remained independently correlated with survival. CONCLUSIONS: For patients in cardiogenic shock, left ventricular function and culprit vessel were independent correlates of one-year survival

OBJECTIVE: We evaluated the significance of combined anterior and inferior ST-segment elevation on the initial electrocardiogram (EKG) in patients with acute myocardial infarction (AMI) and correlated it with AMI size and left ventricular (LV) function. METHODS: We analyzed admission EKGs of 2996 patients with AMI from the GUSTO-I angiographic substudy and the GUSTO-IIb angioplasty substudy who underwent immediate angiography. In all, we identified 1046 patients with anterior ST elevation (ST-segment elevation in > or =2 of leads V1-V4) and divided them into 3 groups: Group 1, anterior + inferior ST elevation (ST elevation in > or =2 of leads II, III, aVF, n =179); Group 2, anterior ST elevation only (<2 of leads II, III, aVF with ST elevation or depression, n = 447); Group 3, anterior ST elevation + superior ST elevation (ST depression in > or =2 of leads II, III, aVF, n = 420). RESULTS: Cardiac risk factors, prior AMI, prior percutaneous transluminal coronary angioplasty or coronary artery bypass graft, Killip class, and thrombolytic therapy assignment did not differ among the 3 groups. Group 1 patients had greater number of leads with ST elevation compared to Groups 2 and 3 (ST elevation in > or =6 leads 83% vs 22% vs 49%, P =.001). Despite greater ST-segment elevation, Group 1 patients had a lower peak CK level (median baseline peak CK 1370 vs 1670 vs 2381 IU, P =.0001) and less LV dysfunction (median ejection fraction 0.53 vs 0.49 vs 0.45, P =.0001; median number of abnormal chords 21 vs 32 vs 40, P =.0001). Angiographically, Group 1 had 2 distinct subsets of patients with either right coronary artery (RCA) (59%) or left anterior descending coronary artery (LAD) (36%) occlusion. In contrast, the infarct-related artery (IRA) was almost entirely the LAD in Groups 2 and 3 (97%). Further, the site of IRA occlusion in Group 1 was mostly proximal RCA (67%) in the RCA subgroup and mid or distal LAD (70%) in the LAD subgroup. ST-segment elevation in lead V1 > or = V3 and absence of progression of ST elevation from lead V1 to V3 on the EKG differentiated IRA-RCA from IRA-LAD in patients with combined anterior and inferior ST elevation. CONCLUSIONS: The AMI size and LV dysfunction in patients with anterior ST elevation is directly related to the direction of ST segment deviation in the leads II, III, aVF; least with inferior ST elevation, intermediate with no ST deviation, and maximal with superior ST elevation (inferior ST depression). Despite greater ST-segment elevation, patients with combined anterior and inferior ST elevation have limited AMI size and preserved LV function. Angiographically, they comprise 2 distinct subsets with either proximal RCA or mid to distal LAD occlusion. A predominant right ventricular and limited inferior LV AMI from a proximal RCA occlusion, or a smaller anterior AMI from a more distal occlusion of LAD may explain their limited AMI size despite greater ST elevation

BACKGROUND: Complement activation mediates myocardial damage that occurs during ischemia and reperfusion through multiple pathways. We performed 2 separate, parallel, double-blind, placebo-controlled trials to determine the effects of pexelizumab (a novel C5 complement monoclonal antibody fragment) on infarct size in patients receiving reperfusion therapy: COMPlement inhibition in myocardial infarction treated with thromboLYtics (COMPLY) and COMplement inhibition in Myocardial infarction treated with Angioplasty (COMMA). The COMPLY trial is reported here. METHODS AND RESULTS: Overall, 943 patients with acute ST-segment elevation myocardial infarction (MI) (20% with isolated inferior MI) receiving fibrinolysis were randomly assigned <6 hours after symptom onset to placebo, pexelizumab 2.0-mg/kg bolus, or pexelizumab 2.0-mg/kg bolus plus 0.05 mg/kg per h for 20 hours. Infarct size determined by creatine kinase-MB area under the curve was the primary analysis, which included patients who received at least some study drug and fibrinolysis (n=920). The median infarct size did not differ by treatment (placebo, 5230; bolus, 4952; bolus plus infusion, 5557 [ng/mL] x h; bolus versus placebo, P=0.85; bolus plus infusion versus placebo, P=0.81), nor did the 90-day composite incidence of death, new or worsening congestive heart failure, shock, or stroke (placebo, 18.6%; bolus, 18.4%; bolus plus infusion, 19.7%). Pexelizumab inhibited complement for 4 hours with bolus-only dosing and for 20 to 24 hours with bolus-plus-infusion dosing, with no increase in infections. CONCLUSIONS: When used adjunctively with fibrinolysis, pexelizumab blocked complement activity but reduced neither infarct size by creatine kinase-MB assessment nor adverse clinical outcomes

BACKGROUND: Complement, activated during myocardial ischemia and reperfusion, causes myocardial damage through multiple processes. The COMplement inhibition in Myocardial infarction treated with Angioplasty (COMMA) trial was performed to determine the effect of pexelizumab, a C5 complement inhibitor, on infarct size in patients with ST-segment-elevation myocardial infarction (MI) undergoing primary percutaneous coronary intervention. METHODS AND RESULTS: In COMMA, 960 patients with MI (20% isolated inferior MI) were randomized to placebo, pexelizumab 2.0-mg/kg bolus, or pexelizumab 2.0-mg/kg bolus and 0.05-mg/kg per h infusion for 20 hours. Infarct size by creatine kinase-MB area under the curve, the primary outcome, did not differ significantly between groups (placebo median, 4393; bolus pexelizumab, 4526; bolus plus infusion pexelizumab, 4713 [ng/mL] x h; P=0.89 for bolus versus placebo; P=0.76 for bolus plus infusion versus placebo), nor did the composite of 90-day death, new or worsening heart failure, shock, or stroke (placebo, 11.1%; bolus, 10.7%; bolus plus infusion, 8.5%). The ninety-day mortality rate was significantly lower with pexelizumab bolus plus infusion (1.8% versus 5.9% with placebo; nominal P=0.014); the bolus-only group had an intermediate mortality rate (4.2%). CONCLUSIONS: In patients with ST-elevation MI undergoing percutaneous coronary intervention, pexelizumab had no measurable effect on infarct size. However, the significant reduction in mortality suggests that pexelizumab may benefit patients through alternative novel mechanisms and provides impetus for additional investigation