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Dive into the research topics where G. Michael Felker is active.

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Featured researches published by G. Michael Felker.


The New England Journal of Medicine | 2000

Underlying Causes and Long-Term Survival in Patients with Initially Unexplained Cardiomyopathy

G. Michael Felker; Richard E. Thompson; Joshua M. Hare; Ralph H. Hruban; Diedre E. Clemetson; David L. Howard; Kenneth L. Baughman; Edward K. Kasper

BACKGROUND Previous studies of the prognosis of patients with heart failure due to cardiomyopathy categorized patients according to whether they had ischemic or nonischemic disease. The prognostic value of identifying more specific underlying causes of cardiomyopathy is unknown. METHODS We evaluated the outcomes of 1230 patients with cardiomyopathy. The patients were grouped into the following categories according to underlying cause: idiopathic cardiomyopathy (616 patients), peripartum cardiomyopathy (51); and cardiomyopathy due to myocarditis (111), ischemic heart disease (91), infiltrative myocardial disease (59), hypertension (49), human immunodeficiency virus (HIV) infection (45), connective-tissue disease (39), substance abuse (37), therapy with doxorubicin (15), and other causes (117). Cox proportional-hazards analysis was used to assess the association between the underlying cause of cardiomyopathy and survival. RESULTS During a mean follow-up of 4.4 years, 417 patients died and 57 underwent cardiac transplantation. As compared with the patients with idiopathic cardiomyopathy, the patients with peripartum cardiomyopathy had better survival (adjusted hazard ratio for death, 0.31; 95 percent confidence interval, 0.09 to 0.98), and survival was significantly worse among the patients with cardiomyopathy due to infiltrative myocardial disease (adjusted hazard ratio, 4.40; 95 percent confidence interval, 3.04 to 6.39), HIV infection (adjusted hazard ratio, 5.86; 95 percent confidence interval, 3.92 to 8.77), therapy with doxorubicin (adjusted hazard ratio, 3.46; 95 percent confidence interval, 1.67 to 7.18), and ischemic heart disease (adjusted hazard ratio, 1.52; 95 percent confidence interval, 1.07 to 2.17). CONCLUSIONS The underlying cause of heart failure has prognostic value in patients with unexplained cardiomyopathy. Patients with peripartum cardiomyopathy appear to have a better prognosis than those with other forms of cardiomyopathy. Patients with cardiomyopathy due to infiltrative myocardial diseases, HIV infection, or doxorubicin therapy have an especially poor prognosis.


The Lancet | 2013

Serelaxin, recombinant human relaxin-2, for treatment of acute heart failure (RELAX-AHF): a randomised, placebo-controlled trial

John R. Teerlink; Gad Cotter; Beth A. Davison; G. Michael Felker; Gerasimos Filippatos; Barry H. Greenberg; Piotr Ponikowski; Elaine Unemori; Adriaan A. Voors; Kirkwood F. Adams; Maria Dorobantu; Liliana Grinfeld; Guillaume Jondeau; Alon Marmor; Josep Masip; Peter S. Pang; Karl Werdan; Angelo J. Trapani; Christopher Bush; Rajnish Saini; Christoph Schumacher; Thomas Severin; Marco Metra

BACKGROUND Serelaxin, recombinant human relaxin-2, is a vasoactive peptide hormone with many biological and haemodynamic effects. In a pilot study, serelaxin was safe and well tolerated with positive clinical outcome signals in patients with acute heart failure. The RELAX-AHF trial tested the hypothesis that serelaxin-treated patients would have greater dyspnoea relief compared with patients treated with standard care and placebo. METHODS RELAX-AHF was an international, double-blind, placebo-controlled trial, enrolling patients admitted to hospital for acute heart failure who were randomly assigned (1:1) via a central randomisation scheme blocked by study centre to standard care plus 48-h intravenous infusions of placebo or serelaxin (30 μg/kg per day) within 16 h from presentation. All patients had dyspnoea, congestion on chest radiograph, increased brain natriuretic peptide (BNP) or N-terminal prohormone of BNP, mild-to-moderate renal insufficiency, and systolic blood pressure greater than 125 mm Hg. Patients, personnel administering study drug, and those undertaking study-related assessments were masked to treatment assignment. The primary endpoints evaluating dyspnoea improvement were change from baseline in the visual analogue scale area under the curve (VAS AUC) to day 5 and the proportion of patients with moderate or marked dyspnoea improvement measured by Likert scale during the first 24 h, both analysed by intention to treat. This trial is registered at ClinicalTrials.gov, NCT00520806. FINDINGS 1161 patients were randomly assigned to serelaxin (n=581) or placebo (n=580). Serelaxin improved the VAS AUC primary dyspnoea endpoint (448 mm × h, 95% CI 120-775; p=0·007) compared with placebo, but had no significant effect on the other primary endpoint (Likert scale; placebo, 150 patients [26%]; serelaxin, 156 [27%]; p=0·70). No significant effects were recorded for the secondary endpoints of cardiovascular death or readmission to hospital for heart failure or renal failure (placebo, 75 events [60-day Kaplan-Meier estimate, 13·0%]; serelaxin, 76 events [13·2%]; hazard ratio [HR] 1·02 [0·74-1·41], p=0·89] or days alive out of the hospital up to day 60 (placebo, 47·7 [SD 12·1] days; serelaxin, 48·3 [11·6]; p=0·37). Serelaxin treatment was associated with significant reductions of other prespecified additional endpoints, including fewer deaths at day 180 (placebo, 65 deaths; serelaxin, 42; HR 0·63, 95% CI 0·42-0·93; p=0·019). INTERPRETATION Treatment of acute heart failure with serelaxin was associated with dyspnoea relief and improvement in other clinical outcomes, but had no effect on readmission to hospital. Serelaxin treatment was well tolerated and safe, supported by the reduced 180-day mortality. FUNDING Corthera, a Novartis affiliate company.


American Journal of Cardiology | 2003

Relation of frequency and severity of mitral regurgitation to survival among patients with left ventricular systolic dysfunction and heart failure.

Benjamin H Trichon; G. Michael Felker; Linda K. Shaw; Christopher H. Cabell; Christopher M. O’Connor

The goal of this study was to examine the frequency of mitral regurgitation (MR) in patients with left ventricular (LV) systolic dysfunction and to relate its presence and severity to long-term survival. Remodeling of the left ventricle after myocyte injury leads to a progressive change in LV size and shape, and it may lead to the development of MR. The frequency of MR and its relation to survival in patients with LV systolic dysfunction has not been completely characterized. We analyzed the histories, coronary anatomy, and degree of MR in patients with symptomatic heart failure and LV ejection fraction <40% who underwent cardiac catheterization between 1986 and 2000. Coxs proportional hazards modeling was used to assess the independent effect of MR on survival. Two thousand fifty-seven patients met study criteria; MR was common in this cohort (56.2%). Of patients with MR, 811 (70.1%) had mild (grades 1+ or 2+) and 345 (29.8%) had moderate or severe (grades 3+ or 4+) regurgitation. Survival rates at 1, 3, and 5 years were significantly lower in patients with moderate to severe MR versus those with mild or no MR (p <0.001). MR was found to be an independent predictor of mortality after multivariable analysis (hazards ratio 1.23, 95% confidence interval 1.13 to 1.34, p = 0.0001). This relation of MR and survival was present in those with ischemic and nonischemic cardiomyopathies. MR is common in patients with LV systolic dysfunction and heart failure. After adjusting for other clinical variables, the presence of MR independently predicted worsened survival.


The New England Journal of Medicine | 2012

Ultrafiltration in Decompensated Heart Failure with Cardiorenal Syndrome

Bradley A. Bart; Steven R. Goldsmith; Kerry L. Lee; Michael M. Givertz; David A. Bull; Margaret M. Redfield; Anita Deswal; Jean L. Rouleau; Martin M. LeWinter; Elizabeth Ofili; Lynne W. Stevenson; Marc J. Semigran; G. Michael Felker; Horng H. Chen; Adrian F. Hernandez; Kevin J. Anstrom; Steven McNulty; Eric J. Velazquez; Jenny C. Ibarra; Alice M. Mascette; Eugene Braunwald

BACKGROUND Ultrafiltration is an alternative strategy to diuretic therapy for the treatment of patients with acute decompensated heart failure. Little is known about the efficacy and safety of ultrafiltration in patients with acute decompensated heart failure complicated by persistent congestion and worsened renal function. METHODS We randomly assigned a total of 188 patients with acute decompensated heart failure, worsened renal function, and persistent congestion to a strategy of stepped pharmacologic therapy (94 patients) or ultrafiltration (94 patients). The primary end point was the bivariate change from baseline in the serum creatinine level and body weight, as assessed 96 hours after random assignment. Patients were followed for 60 days. RESULTS Ultrafiltration was inferior to pharmacologic therapy with respect to the bivariate end point of the change in the serum creatinine level and body weight 96 hours after enrollment (P=0.003), owing primarily to an increase in the creatinine level in the ultrafiltration group. At 96 hours, the mean change in the creatinine level was -0.04±0.53 mg per deciliter (-3.5±46.9 μmol per liter) in the pharmacologic-therapy group, as compared with +0.23±0.70 mg per deciliter (20.3±61.9 μmol per liter) in the ultrafiltration group (P=0.003). There was no significant difference in weight loss 96 hours after enrollment between patients in the pharmacologic-therapy group and those in the ultrafiltration group (a loss of 5.5±5.1 kg [12.1±11.3 lb] and 5.7±3.9 kg [12.6±8.5 lb], respectively; P=0.58). A higher percentage of patients in the ultrafiltration group than in the pharmacologic-therapy group had a serious adverse event (72% vs. 57%, P=0.03). CONCLUSIONS In a randomized trial involving patients hospitalized for acute decompensated heart failure, worsened renal function, and persistent congestion, the use of a stepped pharmacologic-therapy algorithm was superior to a strategy of ultrafiltration for the preservation of renal function at 96 hours, with a similar amount of weight loss with the two approaches. Ultrafiltration was associated with a higher rate of adverse events. (Funded by the National Heart, Lung, and Blood Institute; ClinicalTrials.gov number, NCT00608491.).


Circulation | 2005

Lower Serum Sodium Is Associated With Increased Short-Term Mortality in Hospitalized Patients With Worsening Heart Failure Results From the Outcomes of a Prospective Trial of Intravenous Milrinone for Exacerbations of Chronic Heart Failure (OPTIME-CHF) Study

Liviu Klein; Christopher M. O'Connor; Jeffrey D. Leimberger; Wendy Gattis-Stough; Ileana L. Piña; G. Michael Felker; Kirkwood F. Adams; Robert M. Califf; Mihai Gheorghiade

Background—The prognostic value of serum sodium in patients hospitalized for worsening heart failure has not been well defined. Methods and Results—The Outcomes of a Prospective Trial of Intravenous Milrinone for Exacerbations of Chronic Heart Failure (OPTIME-CHF) study randomized 949 patients with systolic dysfunction hospitalized for worsening heart failure to receive 48 to 72 hours of intravenous milrinone or placebo in addition to standard therapy. In a retrospective analysis, we investigated the relationship between admission serum sodium and the primary end point of days hospitalized for cardiovascular causes within 60 days of randomization, as well as the secondary end points of in-hospital mortality, 60-day mortality, and 60-day mortality/rehospitalization. The number of days hospitalized for cardiovascular causes was higher in the lowest sodium quartile: 8.0 (4.5, 18.5) versus 6 (4, 13) versus 6 (4, 11.5) versus 6 (4, 12) days (P<0.015 for comparison with the lowest quartile). Lower serum sodium was associated with higher in-hospital and 60-day mortality: 5.9% versus 1% versus 2.3% versus 2.3% (P<0.015) and 15.9% versus 6.4% versus 7.8% versus 7% (P=0.002), respectively. There was a trend toward higher mortality/rehospitalization for patients who were in the lowest sodium quartile. Multivariable-adjusted Cox proportional hazards analysis showed that serum sodium on admission, when modeled linearly, predicted increased 60-day mortality: sodium (per 3-mEq/L decrease) had a hazard ratio of 1.18 with a 95% CI of 1.03 to 1.36 (P=0.018). Conclusions—In patients hospitalized for worsening heart failure, admission serum sodium is an independent predictor of increased number of days hospitalized for cardiovascular causes and increased mortality within 60 days of discharge.


Journal of the American College of Cardiology | 2003

Heart failure etiology and response to milrinone in decompensated heart failure: results from the OPTIME-CHF study.

G. Michael Felker; Raymond L. Benza; A.Bleakley Chandler; Jeffrey D. Leimberger; Michael S. Cuffe; Robert M. Califf; Mihai Gheorghiade; Christopher M. O’Connor; Optime-Chf Investigators

OBJECTIVES The goal of this study was to assess the interaction between heart failure (HF) etiology and response to milrinone in decompensated HF. BACKGROUND Etiology has prognostic and therapeutic implications in HF, but its relationship to response to inotropic therapy is unknown. METHODS The Outcomes of a Prospective Trial of Intravenous Milrinone for Exacerbations of Chronic Heart Failure (OPTIME-CHF) study randomized 949 patients with systolic dysfunction and decompensated HF to receive 48 to 72 h of intravenous milrinone or placebo. The primary end point was days hospitalized from cardiovascular causes within 60 days. In a post-hoc analysis, we evaluated the interaction between response to milrinone and etiology of HF. RESULTS The primary end point was 13.0 days for ischemic patients and 11.7 days for nonischemic patients (p = 0.2). Sixty-day mortality was 11.6% for the ischemic group and 7.5% for the nonischemic group (p = 0.03). After adjustment for baseline differences, there was a significant interaction between etiology and the effect of milrinone. Milrinone-treated patients with ischemic etiology tended to have worse outcomes than those treated with placebo in terms of the primary end point (13.6 days for milrinone vs. 12.4 days for placebo, p = 0.055 for interaction) and the composite of death or rehospitalization (42% vs. 36% for placebo, p = 0.01 for interaction). In contrast, outcomes in nonischemic patients treated with milrinone tended to be improved in terms of the primary end point (10.9 vs. 12.6 days placebo) and the composite of death or rehospitalization (28% vs. 35% placebo). CONCLUSIONS Milrinone may have a bidirectional effect based on etiology in decompensated HF. Milrinone may be deleterious in ischemic HF, but neutral to beneficial in nonischemic cardiomyopathy.


Journal of the American College of Cardiology | 2002

A standardized definition of ischemic cardiomyopathy for use in clinical research.

G. Michael Felker; Linda K. Shaw; Christopher M. O’Connor

OBJECTIVES We sought to evaluate the association between the extent of coronary artery disease (CAD) and survival in patients with symptomatic heart failure (HF) and to create the most prognostically powerful clinical definition of ischemic cardiomyopathy. BACKGROUND An ischemic etiology of HF is known to be a predictor of adverse outcome; however, there is no uniform definition for ischemic cardiomyopathy. METHODS We assessed the clinical history and coronary anatomy of patients with symptomatic HF and ejection fraction < or = 40% undergoing diagnostic coronary angiography between 1986 and 1999 (n = 1,921). Five classification schemes were tested to identify the most prognostically powerful method for defining the extent of CAD and to develop the best definition of ischemic cardiomyopathy for prognostic purposes. RESULTS A more extensive CAD was independently associated with shorter survival. When the various classification schemes were compared, a modified number-of-diseased-vessels classification, in which patients with single-vessel disease and no prior history of revascularization or myocardial infarction (MI) were classified as nonischemic, provided the most prognostic power. A definition of ischemic cardiomyopathy that incorporated this definition had more prognostic power than the traditional definition. CONCLUSIONS Angiographically diagnosed ischemic HF is associated with shorter survival than nonischemic HF. A more extensive CAD is independently associated with shorter survival, and patients with single-vessel disease and no history of MI or revascularization should be classified as nonischemic for prognostic purposes. Standardization of the definition of ischemic cardiomyopathy will be useful in the conduct and interpretation of clinical research in HF.


The Lancet | 2009

Relaxin for the treatment of patients with acute heart failure (Pre-RELAX-AHF): a multicentre, randomised, placebo-controlled, parallel-group, dose-finding phase IIb study

John R. Teerlink; Marco Metra; G. Michael Felker; Piotr Ponikowski; Adriaan A. Voors; Beth Davison Weatherley; Alon Marmor; Amos Katz; Jacek Grzybowski; Elaine Unemori; Gad Cotter

BACKGROUND Most patients admitted for acute heart failure have normal or increase blood pressure. Relaxin is a natural human peptide that affects multiple vascular control pathways, suggesting potential mechanisms of benefit for such patients. We assessed the dose response of relaxins effect on symptom relief, other clinical outcomes, and safety. METHODS In a placebo-controlled, parallel-group, dose-ranging study, 234 patients with acute heart failure, dyspnoea, congestion on chest radiograph, and increased brain natriuretic peptide (BNP) or N-terminal prohormone of BNP, mild-to-moderate renal insufficiency, and systolic blood pressure greater than 125 mm Hg were recruited from 54 sites in eight countries and enrolled within 16 h of presentation. Patients were randomly assigned, in a double-blind manner via a telephone-based interactive voice response system, to standard care plus 48-h intravenous infusion of placebo (n=62) or relaxin 10 microg/kg (n=40), 30 microg/kg (n=43), 100 microg/kg (n=39), or 250 microg/kg (n=50) per day. Several clinical endpoints were explored to assess whether intravenous relaxin should be pursued in larger studies of acute heart failure, to identify an optimum dose, and to help to assess endpoint selection and power calculations. Analysis was by modified intention to treat. This study is registered with ClinicalTrials.gov, number NCT00520806. FINDINGS In the modified intention-to-treat population, 61 patients were assessed in the placebo group, 40 in the relaxin 10 microg/kg per day group, 42 in the relaxin 30 microg/kg per day group, 37 in the relaxin 100 microg/kg per day group, and 49 in the relaxin 250 microg/kg per day group. Dyspnoea improved with relaxin 30 microg/kg compared with placebo, as assessed by Likert scale (17 of 42 patients [40%] moderately or markedly improved at 6 h, 12 h, and 24 h vs 14 of 61 [23%]; p=0.044) and visual analogue scale through day 14 (8214 mm x h [SD 8712] vs 4622 mm x h [9003]; p=0.053). Length of stay was 10.2 days (SD 6.1) for relaxin-treated patients versus 12.0 days (7.3) for those given placebo, and days alive out of hospital were 47.9 (10.1) versus 44.2 (14.2). Cardiovascular death or readmission due to heart or renal failure at day 60 was reduced with relaxin (2.6% [95% CI 0.4-16.8] vs 17.2% [9.6-29.6]; p=0.053). The number of serious adverse events was similar between groups. INTERPRETATION When given to patients with acute heart failure and normal-to-increased blood pressure, relaxin was associated with favourable relief of dyspnoea and other clinical outcomes, with acceptable safety.


Journal of the American College of Cardiology | 2013

Effect of Serelaxin on Cardiac, Renal, and Hepatic Biomarkers in the Relaxin in Acute Heart Failure (RELAX-AHF) Development Program Correlation With Outcomes

Marco Metra; Gad Cotter; Beth A. Davison; G. Michael Felker; Gerasimos Filippatos; Barry H. Greenberg; Piotr Ponikowski; Elaine Unemori; Adriaan A. Voors; Kirkwood F. Adams; Maria Dorobantu; Liliana Grinfeld; Guillaume Jondeau; Alon Marmor; Josep Masip; Peter S. Pang; Karl Werdan; Margaret F. Prescott; Christopher Edwards; Angelo J. Trapani; Christopher Bush; Rajnish Saini; Christoph Schumacher; Thomas Severin; John R. Teerlink

OBJECTIVES The aim of this study was to assess the effects of serelaxin on short-term changes in markers of organ damage and congestion and relate them to 180-day mortality in patients with acute heart failure. BACKGROUND Hospitalization for acute heart failure is associated with high post-discharge mortality, and this may be related to organ damage. METHODS The Pre-RELAX-AHF (Relaxin in Acute Heart Failure) phase II study and RELAX-AHF phase III study were international, multicenter, double-blind, placebo-controlled trials in which patients hospitalized for acute heart failure were randomized within 16 h to intravenous placebo or serelaxin. Each patient was followed daily to day 5 or discharge and at days 5, 14, and 60 after enrollment. Vital status was assessed through 180 days. In RELAX-AHF, laboratory evaluations were performed daily to day 5 and at day 14. Plasma levels of biomarkers were measured at baseline and days 2, 5, and 14. All-cause mortality was assessed as a safety endpoint in both studies. RESULTS Serelaxin reduced 180-day mortality, with similar effects in the phase II and phase III studies (combined studies: N = 1,395; hazard ratio: 0.62; 95% confidence interval: 0.43 to 0.88; p = 0.0076). In RELAX-AHF, changes in markers of cardiac (high-sensitivity cardiac troponin T), renal (creatinine and cystatin-C), and hepatic (aspartate transaminase and alanine transaminase) damage and of decongestion (N-terminal pro-brain natriuretic peptide) at day 2 and worsening heart failure during admission were associated with 180-day mortality. Serelaxin administration improved these markers, consistent with the prevention of organ damage and faster decongestion. CONCLUSIONS Early administration of serelaxin was associated with a reduction of 180-day mortality, and this occurred with fewer signs of organ damage and more rapid relief of congestion during the first days after admission.


Journal of the American College of Cardiology | 2010

Troponin Elevation in Heart Failure: Prevalence, Mechanisms, and Clinical Implications

Robb D. Kociol; Peter S. Pang; Mihai Gheorghiade; Gregg C. Fonarow; Christopher M. O'Connor; G. Michael Felker

Circulating biomarkers have become increasingly important in diagnosing and risk stratifying patients with heart failure (HF). While the natriuretic peptides have received much focus, there is increasing interest in the role of circulating cardiac troponin (cTn) in detecting myocardial injury (often subclinical) in those with HF. Accumulating evidence suggests that patients with chronic and acute HF may have measurable levels of circulating cTn, whose detection and magnitude may have prognostic implications. Furthermore, as new, more sensitive cTn assays are being developed, larger numbers of HF patients are found to have detectable cTn with a persistent relationship between magnitude and outcome. This knowledge improves our ability to understand the mechanism of worsening HF, improve risk stratification, and detect potential injury related to new therapeutics in HF. As investigators begin to understand the relationship of detectable cTn to HF outcomes, as well as temporal changes in its magnitude, and its relationship to other circulating biomarkers, more insight may be gained into the progressive nature of cardiac dysfunction and the transition from chronic compensated to acute decompensated HF. Ultimately, this information might allow physicians to guide therapy, choose appropriate therapeutics, and improve HF outcomes.

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John R. Teerlink

San Francisco VA Medical Center

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Adriaan A. Voors

University Medical Center Groningen

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Piotr Ponikowski

Wrocław Medical University

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Kirkwood F. Adams

University of North Carolina at Chapel Hill

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