Angiotensin Receptor-Neprilysin Inhibition in Patients With STEMI vs NSTEMI.

BACKGROUND: Patients who sustain an acute myocardial infarction (AMI), including ST-segment elevation myocardial infarction (STEMI) and non-ST-segment elevation myocardial infarction (NSTEMI), remain at high risk for heart failure (HF), coronary events, and death. Angiotensin-converting enzyme inhibitors have been shown to significantly decrease the risk for cardiovascular events in both STEMI and NSTEMI patients. OBJECTIVES: The objectives were to determine whether angiotensin-receptor blockade and neprilysin inhibition with sacubitril/valsartan, compared with ramipril, has impact on reducing cardiovascular events according to the type of AMI. METHODS: The PARADISE-MI (Prospective ARNI versus ACE inhibitor trial to DetermIne Superiority in reducing heart failure Events after Myocardial Infarction) trial enrolled patients with AMI complicated by left ventricular dysfunction and/or pulmonary congestion and at least 1 risk-enhancing factor. Patients were randomized to either sacubitril/valsartan or ramipril. The primary endpoint was death from cardiovascular causes or incident HF. In this prespecified analysis, we stratified patients according to AMI type. RESULTS: Of 5,661 enrolled patients, 4,291 (75.8%) had STEMI. These patients were younger and had fewer comorbidities and cardiovascular risk factors than NSTEMI patients. After adjustment for potential confounders, the risk for the primary outcome was marginally higher in NSTEMI vs STEMI patients (adjusted HR: 1.19; 95% CI: 1.00-1.41), with borderline statistical significance (P = 0.05). The primary composite outcome occurred at similar rates in patients randomized to sacubitril/valsartan vs ramipril in STEMI (10% vs 12%; HR: 0.87; 95% CI: 0.73-1.04; P = 0.13) and NSTEMI patients (17% vs 17%; HR: 0.97; 95% CI: 0.75-1.25; P = 0.80; P interaction = 0.53). CONCLUSIONS: Compared with ramipril, sacubitril/valsartan did not significantly decrease the risk for cardiovascular death and HF in patients with AMI complicated by left ventricular dysfunction, irrespective of the type of AMI. (Prospective ARNI vs ACE Inhibitor Trial to Determine Superiority in Reducing Heart Failure Events After MI; NCT02924727).

Females present higher dose-adjusted drug concentrations of metoprolol and allopurinol/oxypurinol than males.

Females present a higher risk of adverse drug reactions. Sex-related differences in drug concentrations may contribute to these observations but they remain understudied given the underrepresentation of females in clinical trials. The aim of this study was to investigate whether anthropometric and socioeconomic factors and comorbidities could explain sex-related differences in concentrations and dosing for metoprolol and oxypurinol, the active metabolite of allopurinol. We conducted an analysis of two cross-sectional studies. Participants were self-described "White" adults taking metoprolol or allopurinol selected from the Montreal Heart Institute Hospital Cohort. A total of 1007 participants were included in the metoprolol subpopulation and 459 participants in the allopurinol subpopulation; 73% and 86% of the participants from the metoprolol and allopurinol subpopulations were males, respectively. Females presented higher age- and dose-adjusted concentrations of both metoprolol and oxypurinol (both p < 0.03). Accordingly, females presented higher unadjusted and age-adjusted concentration:dose ratio of both metoprolol and allopurinol/oxypurinol compared to males (all p < 3.0 × 10-4 ). Sex remained an independent predictor of metoprolol concentrations (p < 0.01), but not of oxypurinol concentrations, after adjusting for other predictors. In addition to sex, age, daily dose, use of moderate to strong CYP2D6 inhibitors, weight, and CYP2D6 genotype-inferred phenotype were associated with concentrations of metoprolol (all p < 0.01). Daily dose, weight, estimated glomerular filtration rate (eGFR), and employment status were associated with oxypurinol concentrations (all p < 0.01). Females present higher dose-adjusted concentrations of metoprolol and oxypurinol than males. This suggests the need for sex-specific dosing requirements for these drugs, although this hypothesis should be validated in prospective studies.

Growth Differentiation Factor-15 as a Predictor of Functional Capacity, Frailty, and Ventricular Dysfunction in Patients With Aortic Stenosis and Preserved Left Ventricular Ejection Fraction.

In aortic stenosis (AS), left ventricular (LV) remodeling often occurs before symptom onset, and early intervention may be beneficial. Risk stratification remains challenging and identification of biomarkers may be useful. We evaluated the association between growth differentiation factor-15 (GDF-15) and soluble suppression of tumorigenicity 2 (sST2) and known markers of poor prognosis in AS. Baseline plasma GDF-15 and sST2 levels were measured in 70 patients with moderate-severe AS (aortic valve area <1.5 cm2) and preserved LV ejection fraction (>45%). Patients were categorized into "low GDF-15" versus "high GDF-15" and "low sST2" versus "high sST2" groups. Groups were compared for differences in cardiovascular risk factors, 6-minute walk test, 5 m gait speed, cognitive function (Montreal Cognitive Assessment), and echocardiographic parameters. Overall, 44% of patients were deemed asymptomatic by New York Heart Association class, 61% had severe AS (aortic valve area <1 cm2) and all patients had preserved LV ejection fraction. GDF-15 levels were not predictive of AS severity. However, high GDF-15 (>1,050 pg/ml) was associated with LV dysfunction as shown by lower indexed stroke volume (p <0.01), worse LV global longitudinal strain (p = 0.04), greater mean E/e' (p = 0.02) and indexed left atrial volume (p <0.01). It was also associated with decreased functional capacity with shorter 6-minute walk test (p = 0.01) and slower 5 m gait speed (p = 0.02). Associations between sST2 levels and markers of poor prognosis were less compelling. In this study of patients with moderate to severe AS, elevated GDF-15 levels are associated with impaired functional capacity, poorer performance on fragility testing, and LV dysfunction. In conclusion, GDF-15 may integrate these markers of adverse outcomes into a single biomarker of poor prognosis.

The Effects of Angiotensin Receptor-Neprilysin Inhibition on Major Coronary Events in Patients With Acute Myocardial Infarction: Insights From the PARADISE-MI Trial.

BACKGROUND: In patients who survive an acute myocardial infarction (AMI), angiotensin-converting enzyme inhibitors decrease the risk of subsequent major cardiovascular events. Whether angiotensin-receptor blockade and neprilysin inhibition with sacubitril/valsartan reduce major coronary events more effectively than angiotensin-converting enzyme inhibitors in high-risk patients with recent AMI remains unknown. We aimed to compare the effects of sacubitril/valsartan on coronary outcomes in patients with AMI. METHODS: We conducted a prespecified analysis of the PARADISE-MI trial (Prospective ARNI vs ACE Inhibitors Trial to Determine Superiority in Reducing Heart Failure Events After MI), which compared sacubitril/valsartan (97/103 mg twice daily) with ramipril (5 mg twice daily) for reducing heart failure events after myocardial infarction in 5661 patients with AMI complicated by left ventricular systolic dysfunction, pulmonary congestion, or both. In the present analysis, the prespecified composite coronary outcome was the first occurrence of death from coronary heart disease, nonfatal myocardial infarction, hospitalization for angina, or postrandomization coronary revascularization. RESULTS: Patients were randomly assigned at a median of 4.4 [3.0-5.8] days after index AMI (ST-segment-elevation myocardial infarction 76%, non-ST-segment-elevation myocardial infarction 24%), by which time 89% of patients had undergone coronary reperfusion. Compared with ramipril, sacubitril/valsartan decreased the risk of coronary outcomes (hazard ratio, 0.86 [95% CI, 0.74-0.99], P=0.04) over a median follow-up of 22 months. Rates of the components of the composite outcomes were lower in patients on sacubitril/valsartan but were not individually significantly different. CONCLUSIONS: In survivors of an AMI with left ventricular systolic dysfunction and pulmonary congestion, sacubitril/valsartan-compared with ramipril-reduced the risk of a prespecified major coronary composite outcome. Dedicated studies are necessary to confirm this finding and elucidate its mechanism. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT02924727.

An association study of ABCG2 rs2231142 on the concentrations of allopurinol and its metabolites.

ABCG2 is a gene that codes for the human breast cancer resistance protein (BCRP). It is established that rs2231142 G>T, a single nucleotide polymorphism of the ABCG2 gene, is associated with gout and poor response to allopurinol, a uric acid-lowering agent used to treat this condition. It has also been suggested that oxypurinol, the primary active metabolite of allopurinol, is a substrate of the BCRP. We thus hypothesized that carrying the rs2231142 variant would be associated with decreased oxypurinol concentrations, which would explain the lower reduction in uric acid. We performed a cross-sectional study to investigate the association between the ABCG2 rs2231142 variant and oxypurinol, allopurinol, and allopurinol riboside concentrations in 459 participants from the Montreal Heart Institute Hospital Cohort. Age, sex, weight, use of diuretics, and estimated glomerular filtration rate were all significantly associated with oxypurinol plasma concentration. No association was found between rs2231142 and oxypurinol, allopurinol and allopurinol riboside plasma concentrations. Rs2231142 was not significantly associated with daily allopurinol dose in the overall population, but an association was observed in men, with T carriers receiving higher doses. Our results do not support a major role of ABCG2 in the pharmacokinetics of allopurinol or its metabolites. The underlying mechanism of the association between rs2231142 and allopurinol efficacy requires further investigation.

Association of Hyper-Polypharmacy With Clinical Outcomes in Heart Failure With Preserved Ejection Fraction.

BACKGROUND: Polypharmacy is associated with a poor prognosis in the elderly, however, information on the association of polypharmacy with cardiovascular outcomes in heart failure with preserved ejection fraction is sparse. This study sought to investigate the relationship between polypharmacy and adverse cardiovascular events in patients with heart failure with preserved ejection fraction. METHODS: Baseline total number of medications was determined in 1758 patients with heart failure with preserved ejection fraction enrolled in the Americas regions of the TOPCAT trial (Treatment of Preserved Cardiac Function Heart Failure With an Aldosterone Antagonist), by 3 categories: nonpolypharmacy (<5 medications), polypharmacy (5-9), and hyper-polypharmacy (≥10). We examined the relationship of polypharmacy status with the primary outcome (cardiovascular death, HF hospitalization, or aborted cardiac arrest), hospitalizations for any reason, and serious adverse events. RESULTS: The proportion of patients taking 5 or more medications was 92.5% (inclusive of polypharmacy [38.7%] and hyper-polypharmacy [53.8%]). Over a 2.9-year median follow-up, compared with patients with polypharmacy, hyper-polypharmacy was associated with an increased risk for the primary outcome, hospitalization for any reason and any serious adverse events in the univariable analysis, but not significantly associated with mortality. After multivariable adjustment for demographic and comorbidities, hyper-polypharmacy remained significantly associated with an increased risk for hospitalization for any reason (hazard ratio, 1.22 [95% CI, 1.05-1.41]; P=0.009) and any serious adverse events (hazard ratio, 1.23 [95% CI, 1.07-1.42]; P=0.005), whereas the primary outcome was no longer statistically significant. CONCLUSIONS: Hyper-polypharmacy was common and associated with an elevated risk of hospitalization for any reason and any serious adverse events in patients with heart failure with preserved ejection fraction. There were no significant associations between polypharmacy status and mortality.

Genetic markers associated with cutaneous adverse drug reactions to allopurinol: a systematic review.

Pharmacogenomic markers in the HLA coding genes have been associated with drug hypersensitivity of multiple drugs, including allopurinol. In this systematic review, we summarize the pharmacogenomic evidence available regarding allopurinol-induced cutaneous adverse drug reactions (cADRs). We found that the HLA-B*5801 allele was significantly associated with the risk of severe cADRs in the Han Chinese, Korean, Thai, Japanese and European populations. The association between less severe cADRs and HLA-B*5801 was less consistent. All SNPs identified in genome-wide association studies of common variants were also located in or nearby HLA-B*5801. Future studies should focus on more common but less severe allopurinol-induced cADRs, as well as the potential role of rare variants as predictors of these cADRs.

Coronary-artery bypass surgery in patients with left ventricular dysfunction.

BACKGROUND: The role of coronary-artery bypass grafting (CABG) in the treatment of patients with coronary artery disease and heart failure has not been clearly established. METHODS: Between July 2002 and May 2007, a total of 1212 patients with an ejection fraction of 35% or less and coronary artery disease amenable to CABG were randomly assigned to medical therapy alone (602 patients) or medical therapy plus CABG (610 patients). The primary outcome was the rate of death from any cause. Major secondary outcomes included the rates of death from cardiovascular causes and of death from any cause or hospitalization for cardiovascular causes. RESULTS: The primary outcome occurred in 244 patients (41%) in the medical-therapy group and 218 (36%) in the CABG group (hazard ratio with CABG, 0.86; 95% confidence interval [CI], 0.72 to 1.04; P=0.12). A total of 201 patients (33%) in the medical-therapy group and 168 (28%) in the CABG group died from an adjudicated cardiovascular cause (hazard ratio with CABG, 0.81; 95% CI, 0.66 to 1.00; P=0.05). Death from any cause or hospitalization for cardiovascular causes occurred in 411 patients (68%) in the medical-therapy group and 351 (58%) in the CABG group (hazard ratio with CABG, 0.74; 95% CI, 0.64 to 0.85; P<0.001). By the end of the follow-up period (median, 56 months), 100 patients in the medical-therapy group (17%) underwent CABG, and 555 patients in the CABG group (91%) underwent CABG. CONCLUSIONS: In this randomized trial, there was no significant difference between medical therapy alone and medical therapy plus CABG with respect to the primary end point of death from any cause. Patients assigned to CABG, as compared with those assigned to medical therapy alone, had lower rates of death from cardiovascular causes and of death from any cause or hospitalization for cardiovascular causes. (Funded by the National Heart, Lung, and Blood Institute and Abbott Laboratories; STICH ClinicalTrials.gov number, NCT00023595.).

STICH (Surgical Treatment for Ischemic Heart Failure) trial enrollment.

OBJECTIVES: The aim of this study was to assess the influence of enrolling site location and enrollment performance on the generalizability of STICH (Surgical Treatment for Ischemic Heart Failure) trial results. BACKGROUND: The international STICH trial seeks to define the role of cardiac surgery for patients with ischemic cardiomyopathy. METHODS: Baseline characteristics of 2,136 randomized STICH patients were entered into a multivariate equation created using the Duke Databank for Cardiovascular Diseases to predict their 5-year risk for death without cardiac surgery. Patients ordered by increasing predicted risk were assigned to 1 of 32 risk at randomization (RAR) groups created to share one-thirty-second of total predicted deaths. Numbers of patients sharing the same RAR group were compared between higher and lower enrolling site groupings and for countries tending to enroll high- or low-risk patients. RESULTS: Country of enrollment was a stronger determinant of risk diversity than site enrollment performance among patients enrolled at 127 sites in 26 countries. Mean RAR differences among countries ranged from 9.4 (Singapore) to 18.6 (Germany). However, 1,614 of 2,136 patients (76%) from countries enrolling lower-risk patients shared the same RAR group with patients from countries enrolling higher-risk patients. Baseline characteristics responsible for risk differences of patients enrolled in the 2 country groupings were sufficiently similar to exert little influence on clinical decision making. CONCLUSIONS: STICH randomized patients are characterized by a continuous spectrum of risk, without discordant dominance from any site or country. Clinical site diversity promises to enhance the generalization of STICH trial results to a broad population of patients with ischemic cardiomyopathy. (Comparison of Surgical and Medical Treatment for Congestive Heart Failure and Coronary Artery Disease; NCT00023595).

Coronary bypass surgery with or without surgical ventricular reconstruction.

BACKGROUND: Surgical ventricular reconstruction is a specific procedure designed to reduce left ventricular volume in patients with heart failure caused by coronary artery disease. We conducted a trial to address the question of whether surgical ventricular reconstruction added to coronary-artery bypass grafting (CABG) would decrease the rate of death or hospitalization for cardiac causes, as compared with CABG alone. METHODS: Between September 2002 and January 2006, a total of 1000 patients with an ejection fraction of 35% or less, coronary artery disease that was amenable to CABG, and dominant anterior left ventricular dysfunction that was amenable to surgical ventricular reconstruction were randomly assigned to undergo either CABG alone (499 patients) or CABG with surgical ventricular reconstruction (501 patients). The primary outcome was a composite of death from any cause and hospitalization for cardiac causes. The median follow-up was 48 months. RESULTS: Surgical ventricular reconstruction reduced the end-systolic volume index by 19%, as compared with a reduction of 6% with CABG alone. Cardiac symptoms and exercise tolerance improved from baseline to a similar degree in the two study groups. However, no significant difference was observed in the primary outcome, which occurred in 292 patients (59%) who were assigned to undergo CABG alone and in 289 patients (58%) who were assigned to undergo CABG with surgical ventricular reconstruction (hazard ratio for the combined approach, 0.99; 95% confidence interval, 0.84 to 1.17; P=0.90). CONCLUSIONS: Adding surgical ventricular reconstruction to CABG reduced the left ventricular volume, as compared with CABG alone. However, this anatomical change was not associated with a greater improvement in symptoms or exercise tolerance or with a reduction in the rate of death or hospitalization for cardiac causes. (ClinicalTrials.gov number, NCT00023595.)

Impact of previous percutaneous transluminal coronary angioplasty and/or stenting revascularization on outcomes after surgical revascularization: insights from the imagine study.

AIM: To determine the impact of previous coronary artery revascularization by percutaneous transluminal coronary angioplasty and/or stenting (PCI) on outcome after subsequent coronary artery bypass grafting (CABG). METHODS AND RESULTS: The ischaemia management with Accupril post-bypass Graft via Inhibition of the coNverting Enzyme (IMAGINE) trial, conducted between November 1999 and September 2004, tested whether early initiation of an angiotensin-converting enzyme inhibitor post-CABG, in stable patients with LVEF >or=40%, would reduce cardiovascular events. Of the 2489 patients included in the IMAGINE trial, undergoing their first operation, 430 had a history of PCI prior to surgery (PCI group), and 2059 were referred to surgery without previous PCI (non-PCI group). There was a significant increase in the primary IMAGINE endpoint in the PCI group, HR = 1.53 [1.17-1.98], P = 0.0016. Coronary revascularization, HR = 1.80 [1.13-2.87], P = 0.014, unstable angina requiring hospitalization, HR = 2.43 [1.52-3.89], P = 0.0002, were the two individual components that significantly increased in the PCI group, even when adjusted for baseline characteristics (age, sex, history of myocardial infarction or stroke, diabetes, treatment group, or off-pump surgery). CONCLUSION: Patients with left ventricular ejection fraction >or=40% having a history of PCI prior to surgery had a worse outcome post-CABG than those with no prior PCI. Further studies are needed to investigate whether these results apply for drug eluting stents.

A study to assess the effects of a broad-spectrum immune modulatory therapy on mortality and morbidity in patients with chronic heart failure: the ACCLAIM trial rationale and design.

BACKGROUND: Evidence has accumulated regarding the importance of inflammatory mediators in the development and progression of heart failure (HF). Although targeted anticytokine treatment strategies, specifically antitumour necrosis factor-alpha, have yielded disappointing results, this may simply reflect the redundancy of the cytokine cascade and the fact that antitumour necrosis factor-alpha therapies do not stimulate increased activity of the anti-inflammatory arm of the immune system. Ex vivo exposure of autologous blood to controlled oxidative stress and subsequent intramuscular administration is a device-based procedure shown in experimental studies to have a broad-spectrum effect on a number of immune mediators. These studies have demonstrated that this approach downregulates inflammatory cytokines, whereas several anti-inflammatory cytokines are increased. In a feasibility study of 73 patients with moderate to severe HF, active therapy (versus placebo) had a significant benefit on both mortality and hospitalization, and was not associated with adverse hemodynamic or metabolic effects. METHODS: The Advanced Chronic heart failure CLinical Assessment of Immune Modulation therapy (ACCLAIM) trial is a multicentre, randomized, double-blind, placebo-controlled clinical trial of New York Heart Association functional class II to IV chronic HF patients with left ventricular ejection fraction of 30% or less. Enrolling approximately 2400 subjects at 177 sites, the primary end point of the study was the cumulative incidence (time to first event) of the combined end point of total mortality or hospitalization for cardiovascular causes. The study was completed in late 2005, when 701 primary end point events had occurred and all patients had been treated for six months. CONCLUSIONS: If the ACCLAIM trial confirms earlier results, this approach represents a novel nonpharmacological treatment for HF that targets a pathogenic mechanism contributing to progression of this syndrome not addressed by current therapies.

The heart failure challenge: optimizing medical and surgical management.

The treatment of patients with coronary artery disease and left ventricular dysfunction has improved markedly over the past two decades. Nevertheless, the morbidity and mortality rates remain high in this population. In addition to pharmacological therapies to attenuate neurohumoral overactivation, the present challenge is to find additional therapeutic avenues. Percutaneous coronary intervention, although widely used in patients with coronary artery disease, is more challenging with multivessel disease and associated left ventricular dysfunction, and its optimal use in heart failure remains in question. Cardiac surgical revascularization and surgical ventricular restoration have also been advocated. To date, there are no prospective, randomized clinical studies to prove a benefit from these invasive interventions and to identify which patients may derive the most benefit compared with optimal medical therapy alone. The current management of patients with ischemic heart failure needs to be challenged and requires an objective evaluation of these invasive interventions. The ongoing Surgical Treatment for Ischemic Heart Failure (STICH) trial is the first randomized trial designed to determine the long-term benefits of surgical revascularization and surgical ventricular restoration compared with optimal medical therapy alone. The results of this study will provide additional evidence-based information to guide physicians in the rational allocation of health care resources. The role of percutaneous angioplasty in patients with ischemic heart failure also needs to be addressed objectively.

Angiotensin-converting enzyme inhibition in patients with coronary artery disease and preserved left ventricular function Ischemia Management with Accupril post-bypass graft via inhibition of angiotensin-converting enzyme (IMAGINE) compared with the other major trials in coronary artery disease.

It has been hypothesized that angiotensin-converting enzyme (ACE) inhibition, independent from its effect on ventricular function and blood pressure, could affect the atherosclerotic process and reduce the incidence of ischemic events and its complications. Several large clinical outcome trials were designed to test this hypothesis: QUIET, HOPE, EUROPA, PEACE, and IMAGINE. The results of the PEACE study were recently reported, leaving the IMAGINE study as the last chapter in our efforts to evaluate the role of ACE inhibition in coronary artery disease with preserved left ventricular function. In this report, we compare these studies with respect to their methodology and patient population and analyze the unique nature of the last ongoing study, IMAGINE. The reported studies show that patients with coronary artery disease who are at low-to-moderate or high risk should receive an ACE inhibitor if tolerated. However, when the absolute risk of a patient decreases, and intensive contemporary management is given, with good control of risk factors, the absolute and perhaps relative benefits of an ACE inhibitor decrease and their routine use in these patients may not be warranted. The role of ACE inhibition started early post-coronary artery bypass graft in patients with preserved left ventricular function, and intensive contemporary management remains to be determined and should get answered by the IMAGINE study. Moreover, the IMAGINE population is not only a lower risk population than those enrolled in HOPE or EUROPA, but also the risk for this population is bimodal in nature (early post-revascularization inflammation and thrombosis vs long-term atherosclerosis progression) and may provide further insight into underlying mechanisms.

Treatment of congestive heart failure: present and future.

The treatment of patients with congestive heart failure has markedly improved over the past 25 years. The most successful therapy has been attenuation of neurohumoral overactivation with antagonists of the renin-angiotensin-aldosterone system, as well as beta-adrenergic blockade. Cardiac surgical interventions, which include not only aortocoronary artery bypass surgery but also interventions that remodel the heart and repair the mitral valve, have also been advocated. However, randomized clinical trials to prove their benefit and to identify which patients could derive the most benefit from these interventions are lacking. Cardiac devices, such as biventricular pacemakers (for cardiac resynchronization) and implantable cardiac defibrillators, have proved useful in improving survival and quality of life. The treatment of sleep apnea with continuous positive airway pressure has shown some promise, as has immune modulation therapy, but more research to conclusively prove their efficacy is necessary. Cell therapy with skeletal myoblasts or pluripotential stem cells is an interesting and emerging area of research that shows enormous promise. However, fundamental questions regarding the optimal use of this therapy remain unanswered. Finally, although exciting, these developments, along with the changing demographics of the Canadian population, will require a change in the way we provide care for patients with congestive heart failure. These changes will require greater involvement of health care professionals other than physicians, and greater emphasis on outpatient care, early detection and prevention, and evidence-based practice.

Safety of glycoprotein IIb/IIIa inhibitors in urgent or emergency coronary artery bypass graft surgery.

Approximately 2% to 4% of patients undergo urgent or emergency coronary artery bypass grafting (CABG) for complications of percutaneous coronary intervention (PCI) after treatment with glycoprotein (GP) IIb/IIIa inhibitors. The pharmacokinetic and pharmacodynamic properties of GP IIb/IIIa inhibitors play a large role in determining the safety of their use in the setting of urgent or emergency CABG procedures. Emergency or urgent CABG after treatment with the GP IIb/IIIa inhibitor, abciximab, may be associated with increased risk of hemorrhage and the requirement of platelet transfusions if surgery is performed within 12 h of abciximab discontinuation. Eptifibatide is associated with a similar risk compared with placebo, even when surgery is performed within 2 h of eptifibatide cessation. Limited data for tirofiban show that bleeding is not increased when compared with acetylsalicylic acid or heparin. Eptifibatide and tirofiban appear to have favourable safety profiles compared with abciximab in the setting of emergency or urgent CABG after failed PCI.

Bradykinin metabolism in rat hearts with left-ventricular hypertrophy following myocardial infarction.

The aim of the present study was to assess the contribution of angiotensin I converting enzyme (ACE)and neutral endopeptidase (NEP) in the coronary degradation of bradykinin (BK) after left-ventricular hypertrophy following myocardial infarction (MI) in rats. Myocardial infarction was induced by left descendant coronary artery ligation, and the contribution of ACE and NEP in the degradation of exogenous BK after a single passage through the coronary bed was assessed at 2, 5, and 36 days post-MI. BK degradation rate (V(max)/Km) was found to be significantly lower in hearts at 36 days (3.30 +/- 0.28 min(-1)) compared with 2 days (4.39 +/- 0.32 min(-1)) for noninfarcted hearts, but this reduction was just above the statistical level of significance for post-MI hearts. In infarcted hearts, V(max)/Km was increased significantly 5 days post-MI (4.91 +/- 0.28 min(-1)) compared with the 2 and 36 day-groups (3.43 +/- 0.20 and 2.78 +/- 0.16 min(-1), respectively). The difference between noninfarcted and MI was significant only 2 days post-MI. Treatment with the vasopeptidase inhibitor, omapatrilat, showed that the relative contribution of ACE and NEP combined increased over time in infarcted hearts and became significantly higher 36 versus 2 days post-MI. Finally, the treatment with an ACE inhibitor (enalaprilat) and a NEP inhibitor (retrothiorphan) in the 36-day infarcted and noninfarcted hearts showed that the relative contribution of ACE in infarcted hearts was comparable with that of noninfarcted hearts, whereas the relative contribution of NEP was increased significantly in infarcted hearts. In conclusion, experimental MI in rats induces complex changes in the metabolism of exogenous BK. The changes resulted in an increased relative contribution of NEP 36 days after infarction.

Ischemia Management with Accupril post bypass Graft via Inhibition of angiotensin coNverting enzyme (IMAGINE): a multicentre randomized trial - design and rationale.

BACKGROUND: Coronary artery bypass grafting (CABG) remains the revascularization treatment of choice for patients with severely symptomatic or life-threatening coronary artery disease (CAD). However, 9% to 25% of the patients undergoing CABG will suffer a recurrent ischemic event such as death, recurrent infarction, angina or repeat revascularization. The pathophysiological processes particular to the CABG procedure that may affect graft endothelial function are most active in the early phase after surgery. Angiotensin-converting enzyme (ACE) inhibition has been shown to be effective in reducing or preventing ischemic events in patients with and without left ventricular dysfunction, and in those at high risk for CAD. Nonetheless, no large clinical trail has investigated this role of ACE inhibition in preventing ischemic events early after CABG. OBJECTIVE: The Ischemia Management with Accupril post bypass Graft via Inhibition of angiotensin coNverting Enzyme (IMAGINE) study addressed whether ACE inhibition initiated early after CABG improves short and long term outcomes in patients after CABG. PATIENTS AND METHODS: This multicentre, multinational trial recruited 2204 patients with an uncomplicated course early after CABG from 55 to 65 medical care facilities in Canada, The Netherlands, Belgium and France. Eligible patients with normal left ventricular function were randomly assigned to placebo or quinapril (titrated up to 40 mg daily where possible) within seven to 10 days after CABG. All patients were followed up closely for a minimum of 12 months after random placement. The median treatment period is expected to be approximately 27 months.