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Finn Waagstein

Publications and source records attributed to Finn Waagstein.

At least 19 recordsLinked to original sources
PubMed2006

Hyperinsulinemia: effect on cardiac mass/function, angiotensin II receptor expression, and insulin signaling pathways.

To investigate the association between hyperinsulinemia and cardiac hypertrophy, we treated rats with insulin for 7 wk and assessed effects on myocardial growth, vascularization, and fibrosis in relation to the expression of angiotensin II receptors (AT-R). We also characterized insulin signaling pathways believed to promote myocyte growth and interact with proliferative responses mediated by G protein-coupled receptors, and we assessed myocardial insulin receptor substrate-1 (IRS-1) and p110 alpha catalytic and p85 regulatory subunits of phospatidylinositol 3 kinase (PI3K), Akt, MEK, ERK1/2, and S6 kinase-1 (S6K1). Left ventricular (LV) geometry and performance were evaluated echocardiographically. Insulin decreased AT1a-R mRNA expression but increased protein levels and increased AT2-R mRNA and protein levels and phosphorylation of IRS-1 (Ser374/Tyr989), MEK1/2 (Ser218/Ser222), ERK1/2 (Thr202/Tyr204), S6K1 (Thr421/Ser424/Thr389), Akt (Thr308/Thr308), and PI3K p110 alpha but not of p85 (Tyr508). Insulin increased LV mass and relative wall thickness and reduced stroke volume and cardiac output. Histochemical examination demonstrated myocyte hypertrophy and increases in interstitial fibrosis. Metoprolol plus insulin prevented the increase in relative wall thickness, decreased fibrosis, increased LV mass, and improved function seen with insulin alone. Thus our data demonstrate that chronic hyperinsulinemia decreases AT1a-to-AT2 ratio and increases MEK-ERK1/2 and S6K1 pathway activity related to hypertrophy. These changes might be crucial for increased cardiovascular growth and fibrosis and signs of impaired LV function.

Animals↗
PubMed2006

Effects of autoantibodies removed by immunoadsorption from patients with dilated cardiomyopathy on neonatal rat cardiomyocytes.

INTRODUCTION: Immunoadsorption has been shown to improve cardiac performance and reduce mortality in patients with dilated cardiomyopathy. In this study, the underlying mechanism for these beneficial effects was investigated in cultured rat cardiomyocytes. METHODS AND RESULTS: Immunoadsorption was performed in patients with dilated cardiomyopathy (n=7). Antibody-induced complement-dependent cytotoxicity was investigated by colorimetric MTT. Autoantibodies against the beta(1)-adrenoceptor were detected by ELISA and purified. Column eluent from six patients exhibited a cytotoxic effect, three patients were positive for the beta(1)-adrenoceptor autoantibodies. The purified autoantibodies were able to visualize the beta(1)-adrenoceptors by immunocytofluorescence on rat cardiomyocytes, and also displayed partial agonist properties and induced a positive chronotropic effect, which were blocked by the beta(1)-selective antagonist bisoprolol and the peptide corresponding to the beta(1)-adrenoceptor. Column eluent from one patient induced apoptosis in nick end labelling test (8.1+/-1.7% vs. 2.9+/-1.2% in control, p<0.05). CONCLUSION: Autoantibodies removed by immunoadsorption from patients with dilated cardiomyopathy have a pathophysiological role, as shown by the complement-dependent cytotoxicity and chronotropic action on rat cardiomyocytes. This implies that removal of circulating autoantibodies might be part of the underlying mechanism for improved cardiac function.

Adrenergic beta-Antagonists↗
PubMed2006

Influence of central inhibition of sympathetic nervous activity on myocardial metabolism in chronic heart failure: acute effects of the imidazoline I1-receptor agonist moxonidine.

Although beta-adrenergic blockade is beneficial in heart failure, inhibition of central sympathetic outflow using moxonidine has been associated with increased mortality. In the present study, we studied the acute effects of the imidazoline-receptor agonist moxonidine on haemodynamics, NA (noradrenaline) kinetics and myocardial metabolism. Fifteen patients with CHF (chronic heart failure) were randomized to a single dose of 0.6 mg of sustained-release moxonidine or matching placebo. Haemodynamics, NA kinetics and myocardial metabolism were studied over a 2.5 h time period. There was a significant reduction in pulmonary and systemic arterial pressures, together with a decrease in cardiac index in the moxonidine group. Furthermore, there was a simultaneous reduction in systemic and cardiac net spillover of NA in the moxonidine group. Analysis of myocardial consumption of substrates in the moxonidine group showed a significant increase in non-esterified fatty acid consumption and a possible trend towards an increase in myocardial oxygen consumption compared with the placebo group (P=0.16). We conclude that a single dose of moxonidine (0.6 mg) in patients already treated with a beta-blocker reduced cardiac and overall sympathetic activity. The finding of increased lipid consumption without decreased myocardial oxygen consumption indicates a lack of positive effects on myocardial metabolism under these conditions. We suggest this might be a reason for the failure of moxonidine to prevent deaths in long-term studies in CHF.

Aged↗
PubMed2005

A statin in the treatment of heart failure? Controlled rosuvastatin multinational study in heart failure (CORONA): study design and baseline characteristics.

BACKGROUND: Previous prospective outcome studies of statins have not provided any guidance on benefit-risk in patients with heart failure. AIM: The primary objective is to determine whether rosuvastatin (10 mg) reduces the combined endpoint of cardiovascular mortality, non-fatal myocardial infarction or non-fatal stroke (time to first event). The first secondary endpoint is all-cause mortality. METHODS: CORONA is a randomized, double-blind, placebo-controlled trial. Briefly, men and women, aged > or =60 years with chronic symptomatic systolic heart failure of ischemic aetiology and ejection fraction < or =0.40 (NYHA class III and IV) or < or =0.35 (NYHA class II) were eligible if they were not using or in need of cholesterol lowering drugs. RESULTS: Mean age was 73 years (n=5016; 24% women), with 37% in NYHA II and 62% in NYHA III, ejection fraction 0.31, total cholesterol 5.2 mmol/L. Sixty percent have a history of myocardial infarction, 63% hypertension, and 30% diabetes. Patients are well treated for heart failure with 90% on loop or thiazide diuretics, 42% aldosterone antagonists, 91% ACE inhibitor or AT-I blocker, 75% beta-blockers, and 32% digitalis. CONCLUSION: CORONA is important for three main reasons: (1) A positive result is very important because of the high risk of the population studied, the increasing prevalence of elderly patients with chronic symptomatic systolic heart failure in our society, and the health economic issues involved. (2) If negative, new mechanistic questions about heart failure have to be raised. (3) If neutral we can avoid unnecessary polypharmacy.

Age Factors↗
PubMed2004

New insights into the pathogenesis of dilated cardiomyopathy: possible underlying autoimmune mechanisms and therapy.

In the present study, autoimmune processes involved in the pathogenesis of dilated cardiomyopathy (DCM) are discussed. Genetic predisposition, persistent viral infection, and molecular mimicry have previously been described as the underlying mechanisms of the disease, and prevalence of autoantibodies (AABs) against several intra- and extracellular cardiotropic targets has been confirmed. These autoantibodies are able to disturb the normal physiological activity of the cardiomyocytes. They also could function as mediators in an activated immune system and direct a great deal of attention to injured tissue via (1) complement activation and (2) genesis of circulatory immunocomplexes (CICs) in association with self-antigens. The number as well as duration of accessible autoantigens or CICs seem to play an important role in activation of the antigen-presenting cells (APCs) and, consequently, promotion of autoimmunity. Since AABs play such a decisive role, their exclusion by immunoadsorption (IA) therapy has been discussed as a new approach in DCM treatment. Hitherto, all performed pilot studies using this approach have shown improvement in cardiac function and quality of life in the vast majority of treated DCM patients. The removal of circulating AABs may downregulate the autoimmune system, moderate the inflammatory signals, and hasten the recovery of the affected tissue.

Animals↗
PubMed2004

Consistency of the beneficial effect of metoprolol succinate extended release across a wide range dose of angiotensin-converting enzyme inhibitors and digitalis.

BACKGROUND: The effects of beta-blockade with different extent of angiotensin-converting enzyme inhibitors (ACEI) and digitalization are unknown. To assess the effect of metoprolol succinate controlled release/extended release (CR/XL) combined with high versus low doses of ACEI and digitalis, we analyzed data from The Metoprolol CR/XL Randomized Intervention Trial in Chronic Heart Failure (MERIT-HF) in which patients with heart failure and left ventricular ejection fraction < or =40% were randomized to metoprolol CR/XL versus placebo. METHODS AND RESULTS: Outcome was analyzed separately for those on a low dose (< or =median) of the ACEI or digitalis versus high dose (> median). The mean dose of ACEI in the high-dose group (n = 1457) was 3 times higher than that in the low-dose group (n = 2094). Mortality was reduced to a similar extent in the high- and low-dose ACEI subgroups (RR = .69 versus .64, respectively). Corresponding figures for combined mortality/all hospitalization and for mortality/hospitalization for heart failure were .85 versus .83, and .70 versus .68, respectively. Likewise, reduction in total mortality with metoprolol CR/XL was similar in patients receiving no digitalis (n = 1447; RR = .56), low dose (n = 1122; RR = .71), or high dose (n = 1421; RR = .71). CONCLUSION: This analysis of MERIT-HF demonstrates consistent and similar improvement in outcome of patients receiving metoprolol CR/XL when combined with either a high or low dose of an ACEI or digitalis, or no digitalis at all. Thus regardless of ACEI and digitalis dose and whether patients are treated with digitalis or not, it is very important to add a beta-blocker to the existing heart failure therapy. beta-blockers should not be withheld until target doses of ACEI have been achieved.

Adrenergic beta-Antagonists↗
PubMed2004

Efficacy, safety and tolerability of beta-adrenergic blockade with metoprolol CR/XL in elderly patients with heart failure.

AIM: To study the efficacy and tolerability of beta-blockade in elderly patients with heart failure in the MERIT-HF study. METHODS AND RESULTS: Cox proportional hazards model was used to calculate hazard ratios (HR) with 95% confidence intervals (CI). Risk reduction was defined as (1-HR). In patients > or = 65 years total mortality was reduced by 37% (95% CI 17% to 52%; p=0.0008), sudden death by 43% (95% CI 17% to 61%; p=0.0032), and death from worsening heart failure by 61% (95% CI 32% to 77%; p=0.0005). Hospitalisations for worsening heart failure was reduced by 36% (p=0.0006). Elderly patients with severe heart failure (NYHA class III/IV with ejection fraction < 0.25; n=425, and patients above 75 years (n=490) showed similar risk reductions. Metoprolol CR/XL was safe and well tolerated both during initiating therapy and during long-term follow-up. CONCLUSIONS: Metoprolol CR/XL was easily instituted, safe and well tolerated in elderly patients with systolic heart failure. The data suggest that these are the patients in whom treatment will have the greatest impact as shown by number of lives saved and number of hospitalisations avoided. The time has come to overcome the barriers that physicians perceive to beta-blocker treatment, and to provide it to the large number of elderly patients with heart failure in need of this therapy.

Adrenergic beta-Antagonists↗
PubMed2003

The statin wars.

Explore the source record for details and available documents.

Coronary Disease↗
PubMed2003

Stress echocardiography using transesophageal atrial pacing in rats.

BACKGROUND: Echocardiography is increasingly used for noninvasive evaluation of cardiac function and morphology in small animal models of cardiovascular diseases. The aims of this study were to develop a simple method for stress echocardiography in rats and to evaluate left ventricular function of the postinfarct remodeling heart during stress induced by rapid atrial pacing. METHODS: Myocardial infarction (MI) was induced in rats by ligation of left coronary artery. Rats with 3 week-old MI (n = 9) and sham operation (n = 7) were examined with transthoracic echocardiography during stress induced by transesophageal pacing. The stress protocol consisted of examinations at baseline; during 2 different pacing rates, at 360 and 600 bpm; and during recovery. Systolic blood pressure was measured at each step. RESULTS: Stroke volume decreased at pacing with 600 bpm in both groups compared with baseline and to pacing at 360 bpm (sham group, 0.15 +/- 0.01 vs 0.24 +/- 0.02 mL; MI group, 0.13 +/- 0.01 vs 0.31 +/- 0.02 mL, P <.05). Cardiac index increased at 360 bpm pacing compared with baseline and remained constant at the higher pacing rate in the sham-operated rats (246 +/- 34 vs 192 +/- 25 mL/kg, P <.05). In the MI rats, cardiac index decreased at 600 bpm pacing compared with baseline (195 +/- 9 vs 235 +/- 15 mL/kg, P <.01). Systolic blood pressure did not change during the stress protocol in the groups. CONCLUSION: Stress echocardiography induced by transesophageal pacing in rats is a feasible and simple method for evaluation of left ventricular function. This method may be useful for noninvasive evaluation of left ventricular function under stress conditions in small animal models of heart diseases.

Animals↗
PubMed2003

How should subgroup analyses affect clinical practice? Insights from the Metoprolol Succinate Controlled-Release/Extended-Release Randomized Intervention Trial in Heart Failure (MERIT-HF).

CONTEXT: The Metoprolol CR/XL Randomized Intervention Trial in Chronic Heart Failure (MERIT-HF), the Cardiac Insufficiency Bisoprolol Study II (CIBIS-II), and the Carvedilol Prospective Randomized Cumulative Survival Study (COPERNICUS) have all demonstrated highly significant positive effects on total mortality as well as total mortality plus all-cause hospitalization in patients with heart failure. While none of these trials are large enough to provide definitive results in any particular subgroup, it is of interest for physicians to examine the consistency of results as regards efficacy and safety for various subgroups or risk groups. OBJECTIVE: To summarize results from both predefined as well as post-hoc subgroup analyses performed in the MERIT-HF trial, and to provide guidance as to whether any subgroup is at increased risk, despite an overall strongly positive effect, and to discuss the difficulties and limitations in conducting such subgroup analyses. For some subgroups we performed metaanalyses with data from the CIBIS II and COPERNICUS trials in order to obtain more robust data on mortality in subgroups with a small number of deaths (e.g. for women). SETTING: MERIT-HF was run in 14 countries, and randomized a total of 3,991 patients with symptomatic systolic heart failure (NYHA class II to IV with ejection fraction < or =0.40). Treatment was initiated with a very low dose with careful titration to a maximum target dose of 200 mg metoprolol succinate controlled release/extended release (CR/XL), or highest tolerated dose. MAIN OUTCOME MEASURES: Total mortality (first primary endpoint), total mortality plus all-cause hospitalization (second primary endpoint), and total mortality plus hospitalization for heart failure (first secondary endpoint) analyzed on a time to first event basis. RESULTS: Overall, MERIT-HF demonstrated a 34% reduction in total mortality ( p = 0.00009 nominal) and a 19% reduction for mortality plus all-cause hospitalization ( p = 0.00012). The first secondary endpoint of mortality plus hospitalization for heart failure was reduced by 31% ( p = 0.0000008). The results were remarkably consistent for both primary outcomes and the first secondary outcome across all predefined subgroups as well as nearly all post-hoc subgroups. Metoprolol CR/XL has been very well tolerated, overall as well as in all subgroups analyzed. Overall 87% of the patients reached a dose of 100 mg or more of metoprolol CR/XL once daily, and 64% reached the target dose of 200 mg once daily. CONCLUSION: Our results show that when carefully titrated, metoprolol CR/XL can safely be instituted for the overwhelming majority of outpatients with clinically stable systolic heart failure, with minimal side effects or deterioration. The time has come to overcome the barriers that physicians perceive to beta-blocker treatment, and to provide it to the large number of patients with heart failure in need of this therapy, including also high risk patients like elderly patients, patients with severe heart failure, and patients with diabetes. Because of the increased risk, these are the patients in whom treatment will have the greatest impact as shown by number of lives saved and number of hospitalizations avoided. The target dose should be strived for in all patients who tolerate this dose. We should expect some variation of the treatment effect around the overall estimate as we examine a large number of subgroups due to small sample size in subgroups and due to chance. However, we believe that the best estimate of treatment effect for any particular subgroup should be the overall effect observed in the trial.

Adrenergic beta-Antagonists↗
PubMed2002

Dose of metoprolol CR/XL and clinical outcomes in patients with heart failure: analysis of the experience in metoprolol CR/XL randomized intervention trial in chronic heart failure (MERIT-HF).

OBJECTIVES: We performed a post-hoc subgroup analysis in the Metoprolol CR/XL Randomized Intervention Trial in Chronic Heart Failure (MERIT-HF) with the aim of reporting on the heart rate (HR) response during the titration phase and clinical outcomes from the three-month follow-up visit to end of study in two dosage subgroups: one that had reached more than 100 mg of metoprolol CR/XL once daily (high-dose group; n = 1,202; mean 192 mg) and one that had reached 100 mg or less (low-dose group; n = 412; mean 76 mg). BACKGROUND: Clinicians have questioned whether patients need to reach the target beta-blocker dose to receive benefit. METHODS; Outcome (Cox-adjusted) was compared with all placebo patients with dose available at the three-month visit (n = 1,845). RESULTS: Data indicated somewhat higher risk in the low-dose group compared with the high-dose group. Heart rate was reduced to a similar degree in the two dose groups, indicating higher sensitivity for beta-blockade in the low-dose group. The reduction in total mortality with metoprolol CR/XL compared with placebo was similar: 38% (95% confidence interval [CI], 16 to 55) in high-dose group (p = 0.0022) and also 38% (95% CI, 11 to 57) in the low-dose group (p = 0.010). CONCLUSIONS: Risk reduction was similar in the high- and low-dose subgroups, which, at least partly, may be the result of similar beta-blockade as judged from the HR response. The results support the idea of an individualized dose-titration regimen, which is guided by patient tolerability and the HR response. Further research is needed to shed light on why some patients respond with a marked HR reduction and reduced mortality risk on a relatively small dose of a beta-blocker.

Adrenergic beta-Antagonists↗
PubMed2000

Predictors and evolution of renal function during 9 years following heart transplantation.

Over a 9-yr period, heart transplantation was performed in 200 patients at Sahlgrenska University Hospital. Of these 200 patients, 151 were followed for 1 to 9 yr with regard to renal function, hemodynamics, cyclosporin A concentrations, and complications. Patients with a preoperative serum creatinine >130 micromol/L received inotropic drugs to test for reversibility of renal dysfunction. The end point was graft failure. The average preoperative GFR of 66 +/- 17 ml/min per 1.73 m(2) declined to 52 +/- 19, 44 +/- 16, and 37 +/- 17 at 1, 5, and 9 yr after heart transplantation, respectively. Altogether, the average GFR declined by 44%. There was no significant correlation between the preoperative GFR and postoperative renal function or survival. Recipient age was a predictor of renal function during the entire follow-up. Severe renal dysfunction (GFR <20 ml/min per 1.73 m(2)) developed in 20% of the patients, which was predicted by the recipient age at transplantation together with the GFR 1 yr after transplantation. A nomogram that shows the risk of developing severe renal dysfunction after heart transplantation is presented. Cyclosporin A concentrations and treatment with statins, calcium channel blockers, or angiotensin-converting enzyme inhibitors did not correlate with the evolution of renal function. Patients with a preoperative depressed renal function who improved on inotropic treatment seemed to have a poorer outcome compared with the other study patients.

Adolescent↗
PubMed1990

The effect of transcutaneous electrical nerve stimulation (TENS) on catecholamine metabolism during pacing-induced angina pectoris and the influence of naloxone.

Two invasive studies (invasive study I and invasive study II) showed positive effects of transcutaneous electrical nerve stimulation (TENS) in pacing-induced angina pectoris in terms of increased tolerance to pacing, improved lactate metabolism and less anginal pain. Invasive study I demonstrated a decrease in left ventricular afterload by TENS treatment as reflected by a fall in systolic blood pressure, and this fact was thought to be explained by reduced sympathetic activity since arterial levels of epinephrine and norepinephrine dropped during TENS in TENS responders. In invasive study II, the influence of naloxone on the effects of TENS in pacing-induced angina pectoris was studied in 11 patients with severe coronary artery disease. The patients were catheterized and treated with TENS on 2 occasions; one with a single intravenous (i.v.) dose of saline as placebo and one with a single i.v. dose of 50 mg naloxone, double-blind, in random order. Treatment with TENS increased tolerance to pacing (P less than 0.01 with placebo and P less than 0.01 with naloxone, respectively) and improved lactate metabolism (P less than 0.05 with placebo and P less than 0.01 with naloxone, respectively). The positive effects of TENS were thus reproducible and not reversed by single i.v. doses of naloxone. The results of this study indicate that the effects of TENS on the heart are not mediated by beta-endorphin but do not exclude activation of more short-acting opioids like delta or kappa receptor agonists (met-enkephalin and/or dynorphin) since naloxone has a low affinity for these receptors. It is also possible that non-opioid mechanisms are of importance.(ABSTRACT TRUNCATED AT 250 WORDS)

Angina Pectoris↗