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1.
Pharmacogenomics J ; 18(2): 232-237, 2018 04.
Article in English | MEDLINE | ID: mdl-28440343

ABSTRACT

Despite its established inter-individual variability, sildenafil has been the subject of only a few pharmacogenetic investigations, with limited data regarding the genetic modulators of its pharmacokinetics. We conducted a pharmacogenetic sub-study of patients randomized to sildenafil (n=85) in the RELAX trial, which investigated the impact of high-dose sildenafil in patients with heart failure with preserved left ventricular ejection fraction (HFpEF). In the overall population, the CYP3A4 inferred phenotype appeared associated with the dose-adjusted peak concentrations of sildenafil at week 12 and week 24 (adjusted P=0.045 for repeated measures analysis), although this P-value did not meet our corrected significance threshold of 0.0167. In the more homogeneous Caucasian subgroup, this association was significant (adjusted P=0.0165 for repeated measures). Hence, CYP3A4 inferred phenotype is associated with peak sildenafil dose-adjusted concentrations in patients with HFpEF receiving high doses of sildenafil. The clinical impact of this association requires further investigation.


Subject(s)
Cytochrome P-450 CYP3A/genetics , Genotype , Heart Failure/genetics , Sildenafil Citrate/therapeutic use , Stroke Volume/genetics , Vasodilator Agents/therapeutic use , Aged , Exercise Tolerance/drug effects , Exercise Tolerance/genetics , Female , Heart Failure/blood , Heart Failure/drug therapy , Humans , Male , Middle Aged , Sildenafil Citrate/blood , Sildenafil Citrate/pharmacology , Stroke Volume/drug effects , Vasodilator Agents/blood , Vasodilator Agents/pharmacology
2.
Pharmacogenomics J ; 17(2): 192-200, 2017 03.
Article in English | MEDLINE | ID: mdl-26927285

ABSTRACT

We conducted a meta-analysis of pharmacogenomic substudies of three randomized trials conducted in patients with decompensated heart failure (HF) that were led by National Heart Lung and Blood Institute (NHLBI)-funded HF Network to test the hypothesis that candidate genes modulate net fluid loss and weight change in patients with decompensated HF treated with a furosemide-based diuretic regimen. Although none of the genetic variants previously shown to modulate the effects of loop diuretics in healthy individuals were associated with net fluid loss after 72 h of treatment, a set of rare variants in the APOL1 gene, which codes for apolipoprotein L1 (P=0.0005 in the random effects model), was associated with this end point. Moreover, a common variant in the multidrug resistance protein-4 coding gene (ABCC4, rs17268282) was associated with weight loss with furosemide use (P=0.0001). Our results suggest that both common and rare genetic variants modulate the response to a furosemide-based diuretic regimen in patients with decompensated HF.


Subject(s)
Apolipoproteins/genetics , Furosemide/administration & dosage , Heart Failure/drug therapy , Lipoproteins, HDL/genetics , Multidrug Resistance-Associated Proteins/genetics , Pharmacogenomic Variants , Polymorphism, Single Nucleotide , Sodium Potassium Chloride Symporter Inhibitors/administration & dosage , Administration, Intravenous , Aged , Aged, 80 and over , Apolipoprotein L1 , Clinical Trials as Topic , Female , Fluid Shifts/drug effects , Genotype , Heart Failure/diagnosis , Heart Failure/genetics , Heart Failure/physiopathology , Humans , Male , Middle Aged , Pharmacogenetics , Phenotype , Time Factors , Treatment Outcome , Water-Electrolyte Balance/drug effects
3.
Pharmacogenomics J ; 15(1): 13-9, 2015 Feb.
Article in English | MEDLINE | ID: mdl-24980785

ABSTRACT

It is not yet known whether healthy individuals and patients with a chronic disease have similar attitudes towards pharmacogenomics. Thus we conducted a survey of 175 healthy volunteers, 175 heart failure (HF) patients and 100 heart transplant recipients to compare their opinions on this subject. Most participants (>90%) stated that they would accept pharmacogenomic testing and expressed high hopes regarding its potential applications. Overall, interest for pharmacogenomics was shared equally among the three groups. In contrast, after adjusting for age, gender, education and income, healthy individuals were more likely to voice concerns about potential employment (P=0.008 vs HF, odds ratio (OR)=2.93, confidence interval (CI)=1.33-6.47; P=0.010 vs Transplant, OR=2.46, CI=1.24-4.90) and insurance discrimination (P=0.001 vs HF, OR=5.58, CI=2.01-15.48; P<0.001 vs Transplant, OR=4.98, CI=2.03-12.21) and were possibly more worried by confidentiality issues. These findings highlight the need for strict legislation and proper educational strategies directed at the general population to facilitate the clinical implementation of pharmacogenomics.


Subject(s)
Culture , Heart Failure/psychology , Heart Transplantation/psychology , Hope , Pharmacogenetics , Transplant Recipients/psychology , Adult , Aged , Cross-Sectional Studies , Female , Heart Failure/genetics , Heart Failure/surgery , Humans , Male , Middle Aged , Pharmacogenetics/trends
4.
N Engl J Med ; 365(1): 32-43, 2011 Jul 07.
Article in English | MEDLINE | ID: mdl-21732835

ABSTRACT

BACKGROUND: Nesiritide is approved in the United States for early relief of dyspnea in patients with acute heart failure. Previous meta-analyses have raised questions regarding renal toxicity and the mortality associated with this agent. METHODS: We randomly assigned 7141 patients who were hospitalized with acute heart failure to receive either nesiritide or placebo for 24 to 168 hours in addition to standard care. Coprimary end points were the change in dyspnea at 6 and 24 hours, as measured on a 7-point Likert scale, and the composite end point of rehospitalization for heart failure or death within 30 days. RESULTS: Patients randomly assigned to nesiritide, as compared with those assigned to placebo, more frequently reported markedly or moderately improved dyspnea at 6 hours (44.5% vs. 42.1%, P=0.03) and 24 hours (68.2% vs. 66.1%, P=0.007), but the prespecified level for significance (P≤0.005 for both assessments or P≤0.0025 for either) was not met. The rate of rehospitalization for heart failure or death from any cause within 30 days was 9.4% in the nesiritide group versus 10.1% in the placebo group (absolute difference, -0.7 percentage points; 95% confidence interval [CI], -2.1 to 0.7; P=0.31). There were no significant differences in rates of death from any cause at 30 days (3.6% with nesiritide vs. 4.0% with placebo; absolute difference, -0.4 percentage points; 95% CI, -1.3 to 0.5) or rates of worsening renal function, defined by more than a 25% decrease in the estimated glomerular filtration rate (31.4% vs. 29.5%; odds ratio, 1.09; 95% CI, 0.98 to 1.21; P=0.11). CONCLUSIONS: Nesiritide was not associated with an increase or a decrease in the rate of death and rehospitalization and had a small, nonsignificant effect on dyspnea when used in combination with other therapies. It was not associated with a worsening of renal function, but it was associated with an increase in rates of hypotension. On the basis of these results, nesiritide cannot be recommended for routine use in the broad population of patients with acute heart failure. (Funded by Scios; ClinicalTrials.gov number, NCT00475852.).


Subject(s)
Dyspnea/drug therapy , Heart Failure/drug therapy , Natriuretic Agents/therapeutic use , Natriuretic Peptide, Brain/therapeutic use , Patient Readmission/statistics & numerical data , Acute Disease , Aged , Double-Blind Method , Dyspnea/etiology , Female , Heart Failure/complications , Heart Failure/mortality , Humans , Hypotension/chemically induced , Intention to Treat Analysis , Kidney Diseases/etiology , Male , Middle Aged , Natriuretic Agents/adverse effects , Natriuretic Peptide, Brain/adverse effects , Recurrence
5.
Am Heart J ; 146(2): 291-7, 2003 Aug.
Article in English | MEDLINE | ID: mdl-12891198

ABSTRACT

OBJECTIVES: The purpose of this study was to assess the effects of amlodipine on neurohormones and oxidative stress in nonischemic cardiomyopathy, and determine the relationship between baseline and posttreatment levels of these markers with survival. BACKGROUND: Neurohormones and oxidative stress are important in the pathophysiology of heart failure. Calcium-channel blockers are associated with poor outcomes in patients with heart failure, in part due to neurohormonal activation. In contrast, amlodipine, a second-generation dihydropyridine, has a more favorable clinical profile. METHODS: In the Prospective Randomized Amlodipine Survival Evaluation 2 (PRAISE-2) trial, a subset of 181 patients with nonischemic cardiomyopathy were randomized to amlodipine (10 mg/day) or placebo. Blood samples were evaluated at baseline, 2 weeks and 26 weeks for norepinephrine, epinephrine, angiotensin II, dopamine, N-terminal pro-atrial natriuretic peptide (Nt-pro-ANP), brain natriuretic peptide (BNP), adrenolutin and malondialdehyde. RESULTS: There was no difference in levels of neurohormones or oxidative stress markers between the amlodipine and placebo groups at the different times. Both Nt-pro-ANP and BNP decreased at 2 weeks and at 26 weeks. Baseline Nt-pro-ANP correlated with survival in multivariate analysis (P =.001). A strong relationship was found between a reduction in BNP at 26 weeks and survival, with a hazard ratio of 0.153 (95% CI 0.051-0.461, P =.017). No relationship was found between markers of oxidative stress and survival. CONCLUSIONS: We conclude that amlodipine does not affect circulating neurohormones and oxidative stress markers in patients with nonischemic cardiomyopathy treated with angiotensin-converting enzyme inhibitors, digoxin and diuretics. In addition, low circulating Nt-pro-ANP and a reduction in BNP over time confers a good prognosis.


Subject(s)
Amlodipine/pharmacology , Calcium Channel Blockers/pharmacology , Heart Failure/drug therapy , Neurotransmitter Agents/blood , Oxidative Stress/drug effects , Amlodipine/therapeutic use , Calcium Channel Blockers/therapeutic use , Catecholamines/blood , Female , Heart Failure/blood , Heart Failure/mortality , Humans , Male , Middle Aged , Multivariate Analysis , Survival Analysis
6.
Am Heart J ; 145(5): 926-32, 2003 May.
Article in English | MEDLINE | ID: mdl-12766756

ABSTRACT

OBJECTIVES: The purpose of this study was to assess whether adrenolutin, the inert product of the highly reactive molecules aminochromes, is increased in severe chronic heart failure and whether it is associated with a poor prognosis. BACKGROUND: Experimental evidence suggests that oxidative products of catecholamines, aminochromes, are more cardiotoxic than unoxidized catecholamines and may be increased in heart failure. METHODS: Adrenolutin was measured at baseline and at 1 and 3 months in 263 patients with chronic New York Heart Association class III or IV heart failure and a left ventricular ejection fraction of 22% +/- 7%. Adrenolutin levels were compared with normal levels, and their relation to prognosis was evaluated. RESULTS: Baseline adrenolutin was increased (55 +/- 90 pg/mL vs 8.4 +/- 9.1 pg/mL for control, P <.02) and remained increased at 1 month (49 +/- 65 pg/mL). During a mean follow-up of 309 +/- 148 days (22-609 days), 57 patients died. Baseline adrenolutin levels correlated with mortality rates by univariate and multivariate analyses (relative risk 1.06, 95% CI 1.01-1.10 for each 17.9-pg/mL rise, P =.032). Left ventricular ejection fraction (P =.013) and New York Heart Association class (P =.009) were the only other variables associated with survival. Age, sex, plasma creatinine, plasma N-terminal atrial natriuretic peptide, and plasma norepinephrine levels were not retained in our model. Adrenolutin levels 1 month after random assignment were not significantly correlated with total mortality rate (P =.061) but were correlated with mortality rate from low output (relative risk 1.14, 95% CI 1.06-1.22, P =.002). CONCLUSIONS: Plasma adrenolutin is increased in patients with heart failure and correlates with a poor prognosis independent of other important predictors of survival. This finding has potentially important pathophysiologic, prognostic, and therapeutic implications.


Subject(s)
Heart Failure/blood , Indoles/blood , Aged , Analysis of Variance , Biomarkers/blood , Canada , Catecholamines/blood , Chronic Disease , Female , Heart Failure/mortality , Heart Failure/physiopathology , Humans , Male , Middle Aged , Prognosis , Quinolines/therapeutic use , Reference Values , Stroke Volume , Vasodilator Agents/therapeutic use
8.
Can J Cardiol ; 18(5): 525-35, 2002 May.
Article in English | MEDLINE | ID: mdl-12032579

ABSTRACT

The present review describes the knowledge of microalbuminuria as a cardiovascular risk indicator. Microalbuminuria is usually defined as a urinary albumin excretion rate of 30 to 300 mg in a 24 h urine collection, or as a urinary albumin excretion rate of 20 to 200 mg/min in a timed overnight urine collection, although microalbuminuria was demonstrated to be a predictor for cardiovascular events at levels below these conventional cut-off values. More than one consecutive urine collection is preferred given the high day to day variability of urinary albumin excretion. Microalbuminuria is frequently present and a known cardiovascular risk indicator in diabetic populations. Also, in hypertensive and general populations, microalbuminuria is common and has been associated with an adverse atherogenic risk profile and a higher prevalence of cardiovascular disease. Moreover, evidence strongly suggests that microalbuminuria is also an independent predictor of cardiovascular disease in these populations. However, more prospective studies are needed to elucidate fully the value of microalbuminuria as a cardiovascular risk indicator in hypertensive and general populations. Generalized endothelial dysfunction has been hypothesized to be the underlying factor for microalbuminuria on one hand and the underlying factor for increased cardiovascular risk on the other. In this respect, the loss of the glycosaminoglycan heparin sulphate might be an important pathophysiological mechanism. This hypothesis needs further clarification, especially in nondiabetic populations.


Subject(s)
Albuminuria/urine , Cardiovascular Diseases/urine , Albuminuria/diagnosis , Albuminuria/epidemiology , Cardiovascular Diseases/epidemiology , Comorbidity , Diabetes Mellitus/epidemiology , Diabetes Mellitus/urine , Endothelium, Vascular/physiopathology , Humans , Hypertension/epidemiology , Hypertension/urine , Predictive Value of Tests , Prevalence , Risk Factors , Urinalysis/methods
9.
J Mol Cell Cardiol ; 33(11): 2023-35, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11708846

ABSTRACT

Cardiac endothelin-1 (ET-1) levels and ET receptor expression are increased in congestive heart failure (CHF). In order to determine whether this results in increased responsiveness of ET-A or ET-B receptors to ET-1, we evaluated the contractile effects of ET-1 in isolated papillary muscles isolated from hearts of control rats and from rats 4 weeks post myocardial infarction (MI) having received no therapy or chronic quinapril therapy. The ET-1 dose-response was biphasic in normal muscles. The use of the selective ET-A receptor antagonist BQ123 and the selective ET-B receptor antagonist BQ788 revealed that the initial decrease in tension was the result of ET-B receptor stimulation. Blockade of nitric oxide (NO) production with L-NAME abolished the initial decrease in tension. MI resulted in CHF that was partially reversed by quinapril. In MI, the positive inotropic effects of ET-1 were enhanced due to the loss of the initial ET-B receptor mediated decrease in tension, as well as an increase in the positive inotropic effects of ET-A receptors. This was associated with an increase in ET-A and ET-B receptor mRNA and a decrease in cardiac ecNOS protein. Four weeks of therapy with quinapril attenuated the positive inotropic effects of ET-1 and prevented the increase in ET-A receptor mRNA. Although quinapril did not restore the effects of ET-B receptor stimulation or prevent the increase in ET-B mRNA, it did restore cardiac ecNOS protein expression. Thus, the inotropic response to ET-1 is biphasic due to an overall positive inotropic effect of ET-A receptor stimulation and an ET-B receptor mediated decrease in contractility at low ET-1 concentrations which appears to be mediated by cardiac ecNOS (NO). In post-MI CHF, responsiveness to ET-A receptors increases and the ET-B mediated negative inotropic response is lost despite an increase in both receptor subtypes. Quinapril therapy attenuates these effects and normalises cardiac ecNOS protein.


Subject(s)
Endothelin-1/metabolism , Isoquinolines/pharmacology , Myocardial Contraction , Myocardial Infarction/metabolism , Tetrahydroisoquinolines , Angiotensin-Converting Enzyme Inhibitors/pharmacology , Animals , Antihypertensive Agents/pharmacology , Binding, Competitive , Body Weight , Dose-Response Relationship, Drug , Endothelium, Vascular/cytology , Endothelium, Vascular/metabolism , Heart Failure/metabolism , Hemodynamics , Kinetics , Male , Muscles/metabolism , Myocardium/cytology , Myocardium/metabolism , Nitric Oxide Synthase/metabolism , Nitric Oxide Synthase Type III , Oligopeptides/pharmacology , Organ Culture Techniques , Organ Size , Papillary Muscles/metabolism , Peptides, Cyclic/pharmacology , Piperidines/pharmacology , Protein Binding , Quinapril , RNA, Messenger/metabolism , Rats , Rats, Wistar , Receptor, Endothelin A , Receptor, Endothelin B , Receptors, Endothelin/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Time Factors , Vasoconstrictor Agents/pharmacology , Viper Venoms/pharmacology
10.
Am Heart J ; 142(6): 1056-64, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11717612

ABSTRACT

OBJECTIVE: Our purpose was to study the changes in vasoconstrictive neurohormones, N-terminal proatrial natriuretic peptide (Nt-proANP), and brain natriuretic peptide (BNP) and their relationship with left ventricular (LV) remodeling soon after anterior myocardial infarction (MI). BACKGROUND: The Healing and Afterload Reducing Therapy (HEART) trial has shown that early use of ramipril improves left ventricular ejection fraction (LVEF) and attenuates LV remodeling when initiated soon after MI. This neurohumoral substudy of HEART investigates the changes in vasoconstrictive and natriuretic peptides and their relationship with LV remodeling. METHODS: One hundred twenty-two patients had blood drawn for the measurement of catecholamines, endothelin-I, angiotensin II, Nt-proANP and BNP, and prostacyclins within 24 hours of an MI, and at 3, 14, and 90 days after the MI. Quantitative echocardiograms were performed at baseline and at 14 days. RESULTS: All neurohormones except angiotensin II (P =.12) and prostaglandins were significantly elevated at baseline. Vasoconstrictive neurohormones decreased significantly over time but remained elevated at 14 days. Both Nt-proANP and BNP were elevated within the first 14 days. BNP decreased significantly by 90 days, whereas Nt-proANP exhibited no change between 14 and 90 days. Ramipril decreased plasma levels of angiotensin II at 3 days but had no effect on the other neurohormones. CONCLUSIONS: Neurohumoral activation occurs and persists in patients with anterior MI and overall preserved LV function. Ramipril had only a modest impact on neurohormones despite its significant benefits on LV remodeling soon after MI.


Subject(s)
Atrial Natriuretic Factor/blood , Catecholamines/blood , Myocardial Infarction/physiopathology , Natriuretic Peptide, Brain/blood , Ventricular Remodeling , Angiotensin II/blood , Biomarkers/blood , Dopamine/blood , Double-Blind Method , Epinephrine/blood , Epoprostenol/blood , Female , Humans , Male , Middle Aged , Nerve Tissue Proteins , Norepinephrine/blood , Ramipril/administration & dosage , Stroke Volume/drug effects
11.
Circulation ; 104(15): 1856-62, 2001 Oct 09.
Article in English | MEDLINE | ID: mdl-11591626

ABSTRACT

The cardiovascular system is regulated by hemodynamic and neurohumoral mechanisms. These regulatory systems play a key role in modulating cardiac function, vascular tone, and structure. Although neurohumoral systems are essential in vascular homeostasis, they become maladaptive in disease states such as hypertension, coronary disease, and heart failure. The clinical success of ACE inhibitors has led to efforts to block other humoral systems. Neutral endopeptidase (NEP) is an endothelial cell surface zinc metallopeptidase with similar structure and catalytic site. NEP is the major enzymatic pathway for degradation of natriuretic peptides, a secondary enzymatic pathway for degradation of kinins, and adrenomedullin. The natriuretic peptides can be viewed as endogenous inhibitors of the renin angiotensin system. Inhibition of NEP increases levels of atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP) of myocardial cell origin, and C-type natriuretic peptide (CNP) of endothelial cell origin as well as bradykinin and adrenomedullin. By simultaneously inhibiting the renin-angiotensin-aldosterone system and potentiating the natriuretic peptide and kinin systems, vasopeptidase inhibitors reduce vasoconstriction, enhance vasodilation, improve sodium/water balance, and, in turn, decrease peripheral vascular resistance and blood pressure and improve local blood flow. Within the blood vessel wall, this leads to a reduction of vasoconstrictor and proliferative mediators such as angiotensin II and increased local levels of bradykinin (and, in turn, nitric oxide) and natriuretic peptides. Preliminary clinical experiences with vasopeptidase inhibitors are encouraging. Thus, the combined inhibition of ACE and neutral endopeptidase is a new and promising approach to treat patients with hypertension, atherosclerosis, or heart failure.


Subject(s)
Cardiovascular Diseases/drug therapy , Cardiovascular System/enzymology , Enzyme Inhibitors/therapeutic use , Peptide Hydrolases/drug effects , Angiotensin-Converting Enzyme Inhibitors/therapeutic use , Animals , Cardiovascular System/drug effects , Endothelium, Vascular/metabolism , Humans , Kinins/metabolism , Natriuretic Agents/metabolism , Neprilysin/antagonists & inhibitors , Renin-Angiotensin System/drug effects , Renin-Angiotensin System/physiology , Vasomotor System/drug effects , Vasomotor System/physiology
12.
Circulation ; 104(17): 2075-81, 2001 Oct 23.
Article in English | MEDLINE | ID: mdl-11673349

ABSTRACT

BACKGROUND: Some controversy exists as to the effects of endothelin (ET) receptor antagonism on long-term post-myocardial infarction (MI) evolution, particularly as it relates to the timing of the intervention after MI (<24 hours versus 10 days). METHODS AND RESULTS: Sham rats and rats surviving an acute MI for >20 hours (n=301) were assigned to treatment with saline or the nonselective ET(A) and ET(B) receptor antagonist LU 420627 (LU) started <24 hours (early) or 10 days (late) after MI and continued for 100 days. Long-term LU treatment led to increased mortality of rats with large MI, regardless of the timing of initiation of therapy. Early initiation of LU reduced survival from 61% to 16% (P<0.001 versus untreated), and later initiation reduced survival to 36% (P=0.012 versus untreated and P<0.001 versus early initiation). Early initiation of LU led to scar thinning, further left ventricular (LV) dilatation, LV dysfunction, and an excessive rise in right ventricular systolic pressure. Later initiation of LU did not modify scar formation but resulted in LV dilatation and dysfunction compared with the untreated group. Cardiac fibrosis tended to increase in the LU-treated MI groups. LU in the sham group reduced cardiac endothelial constitutive nitric oxide synthase but did not modify the changes that occurred with a large MI. CONCLUSIONS: The use of the nonselective ET(A) and ET(B) receptor antagonist LU results in reduced survival, ventricular dilatation, and dysfunction whether started early or late after MI. Early initiation of LU resulted in scar expansion and a particularly unfavorable outcome.


Subject(s)
Endothelin Receptor Antagonists , Myocardial Infarction/physiopathology , Animals , Dilatation, Pathologic/chemically induced , Dilatation, Pathologic/physiopathology , Disease Models, Animal , Drug Administration Schedule , Endothelins/pharmacology , Ligands , Male , Myocardial Infarction/drug therapy , Peptide Fragments/pharmacology , Rats , Rats, Wistar , Receptor, Endothelin A , Receptor, Endothelin B , Receptors, Endothelin/agonists , Survival Rate , Time , Ventricular Dysfunction/chemically induced , Ventricular Dysfunction/physiopathology
13.
Circulation ; 104(8): 939-44, 2001 Aug 21.
Article in English | MEDLINE | ID: mdl-11514383

ABSTRACT

BACKGROUND: The role of kinins in the cardioprotective effects of ACE inhibitors remains controversial. METHODS AND RESULTS: Right ventricular pressure overload in rabbits was produced by pulmonary artery banding for 21 days. Rabbits were untreated, or they received the ACE inhibitor ramipril with or without bradykinin B(1) and B(2) receptor blockers or the angiotensin (Ang) II type I (AT(1)) receptor blocker losartan. Pulmonary artery banding caused right ventricular hypertrophy, depressed papillary muscle contractility, and loss of Ang II contractile effects because of a signaling defect downstream of AT(1) receptors. Paradoxically, AT(1) receptor density and G protein alpha subunits alphaq and alphai1/2 increased. Inotropic responsiveness to the alpha-receptor agonist phenylephrine was normal. Ramipril preserved cardiac contractility, but this effect was attenuated by simultaneous use of kinin receptor blockers. Ramipril also maintained responsiveness to Ang II and prevented AT(1) receptor and G protein upregulation. The simultaneous use of a kinin receptor blocker attenuated but did not prevent upregulation in the AT(1) receptor and G protein. Losartan had no effect on baseline contractility, but it maintained cardiac inotropic responsiveness to Ang II, prevented upregulation of AT(1) receptors, but did not modify G protein upregulation. CONCLUSIONS: Pressure overload of the right ventricle decreases contractility, uncouples AT(1) receptors to downstream signaling pathways, and changes the expression of components of the AT(1) receptor signaling pathway. Ramipril attenuates these effects via kinins. Interventions that prevent local increases in Ang II or block AT(1) receptors also prevent decreased responsiveness of the AT(1) receptor in this model.


Subject(s)
Angiotensin-Converting Enzyme Inhibitors/pharmacology , Kinins/metabolism , Receptors, Angiotensin/metabolism , Signal Transduction/drug effects , Ventricular Dysfunction, Right/drug therapy , Angiotensin II/metabolism , Angiotensin II/pharmacology , Angiotensin Receptor Antagonists , Animals , Bradykinin Receptor Antagonists , Disease Models, Animal , Dose-Response Relationship, Drug , Electric Stimulation , GTP-Binding Proteins/metabolism , Hemodynamics/drug effects , In Vitro Techniques , Losartan/pharmacology , Male , Myocardial Contraction/drug effects , Myocardium/metabolism , Myocardium/pathology , Organ Size/drug effects , Papillary Muscles/drug effects , Papillary Muscles/metabolism , Protein Subunits , Pulmonary Artery/physiopathology , Rabbits , Ramipril/pharmacology , Receptor, Angiotensin, Type 1 , Receptor, Angiotensin, Type 2 , Ventricular Dysfunction, Right/physiopathology
15.
N Engl J Med ; 344(22): 1651-8, 2001 May 31.
Article in English | MEDLINE | ID: mdl-11386263

ABSTRACT

BACKGROUND: Beta-blocking agents reduce the risk of hospitalization and death in patients with mild-to-moderate heart failure, but little is known about their effects in severe heart failure. METHODS: We evaluated 2289 patients who had symptoms of heart failure at rest or on minimal exertion, who were clinically euvolemic, and who had an ejection fraction of less than 25 percent. In a double-blind fashion, we randomly assigned 1133 patients to placebo and 1156 patients to treatment with carvedilol for a mean period of 10.4 months, during which standard therapy for heart failure was continued. Patients who required intensive care, had marked fluid retention, or were receiving intravenous vasodilators or positive inotropic drugs were excluded. RESULTS: There were 190 deaths in the placebo group and 130 deaths in the carvedilol group. This difference reflected a 35 percent decrease in the risk of death with carvedilol (95 percent confidence interval, 19 to 48 percent; P=0.00013, unadjusted; P=0.0014, adjusted for interim analyses). A total of 507 patients died or were hospitalized in the placebo group, as compared with 425 in the carvedilol group. This difference reflected a 24 percent decrease in the combined risk of death or hospitalization with carvedilol (95 percent confidence interval, 13 to 33 percent; P<0.001). The favorable effects on both end points were seen consistently in all the subgroups we examined, including patients with a history of recent or recurrent cardiac decompensation. Fewer patients in the carvedilol group than in the placebo group withdrew because of adverse effects or for other reasons (P=0.02). CONCLUSIONS: The previously reported benefits of carvedilol with regard to morbidity and mortality in patients with mild-to-moderate heart failure were also apparent in the patients with severe heart failure who were evaluated in this trial.


Subject(s)
Adrenergic beta-Antagonists/therapeutic use , Carbazoles/therapeutic use , Heart Failure/drug therapy , Propanolamines/therapeutic use , Adrenergic beta-Antagonists/adverse effects , Aged , Carbazoles/adverse effects , Carvedilol , Chronic Disease , Double-Blind Method , Female , Heart Failure/mortality , Hospitalization/statistics & numerical data , Humans , Male , Middle Aged , Propanolamines/adverse effects , Proportional Hazards Models , Prospective Studies , Risk , Severity of Illness Index , Survival Analysis
16.
Peptides ; 22(6): 953-62, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11390026

ABSTRACT

The purposes of this study were to evaluate and to compare the effects of simultaneous angiotensin-converting enzyme (ACE) and neutral endopeptidase 24.11 (NEP) inhibition by the vasopeptidase inhibitor omapatrilat (1 mg. kg(-1). day(-1)) with those of the selective ACE inhibitor enalapril (1 mg. kg(-1). day(-1)) on survival, cardiac hemodynamics, and bradykinin (BK) and des-Arg(9)-BK levels in cardiac tissues 24 h after myocardial infarction (MI) in rats. The effect of the co-administration of both B(1) and B(2) kinin receptor antagonists (2.5 mg. kg(-1). day(-1) each) with metallopeptidase inhibitors was also evaluated. The pharmacological treatments were infused subcutaneously using micro-osmotic pumps for 5 days starting 4 days before the ligation of the left coronary artery. Immunoreactive kinins were quantified by highly sensitive and specific competitive enzyme immunoassays. The post-MI mortality of untreated rats with a large MI was high; 74% of rats dying prior to the hemodynamic study. Mortality in the other MI groups was not significantly different from that of the untreated MI rats. Cardiac BK levels were not significantly different in the MI vehicle-treated group compared with the sham-operated rats. Both omapatrilat and enalapril treatments of MI rats significantly increased cardiac BK concentrations compared with the sham-operated group (P < 0.05). However, cardiac BK levels were significantly increased only in the MI omapatrilat-treated rats compared with the MI vehicle-treated group (P < 0.01). Cardiac des-Arg(9)-BK concentrations were not significantly modified by MI, and MI with omapatrilat or enalapril treatment compared with the sham-operated group. The co-administration of both kinin receptor antagonists with MI omapatrilat- and enalapril-treated rats had no significant effect on cardiac BK and des-Arg(9)-BK levels. Thus, the significant increase of cardiac BK concentrations by omapatrilat could be related to a biochemical or a cardiac hemodynamic parameter on early (24 h) post-MI state.


Subject(s)
Angiotensin-Converting Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/pharmacology , Kinins/metabolism , Myocardial Infarction/metabolism , Myocardium/metabolism , Pyridines/pharmacology , Thiazepines/pharmacology , Animals , Aspartate Aminotransferases/biosynthesis , Bradykinin Receptor Antagonists , Creatine Kinase/biosynthesis , Hemodynamics , Immunoenzyme Techniques , L-Lactate Dehydrogenase/biosynthesis , Male , Metalloendopeptidases/antagonists & inhibitors , Neprilysin/antagonists & inhibitors , Peptidyl-Dipeptidase A/metabolism , Protease Inhibitors/pharmacology , Rats , Rats, Wistar , Receptor, Bradykinin B1 , Receptor, Bradykinin B2 , Time Factors , Troponin T/biosynthesis
17.
J Card Fail ; 7(2): 153-7, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11420767

ABSTRACT

BACKGROUND: New York Heart Association (NYHA) class and treadmill exercise test variables are widely used for estimating prognosis and measuring the outcomes of treatment in patients with heart failure, but they do not take patients' perceptions into account. METHODS AND RESULTS: Five hundred forty-five patients enrolled in a multicenter 24-week comparison of the effects of omapatrilat and lisinopril on functional capacity in patients with heart failure reported a visual analog scale (VAS) score of their overall health perception at week 12 of the study. A total of 27 first events, defined as death or worsening heart failure (hospitalization, emergency room visit, or study discontinuation), occurred in the subsequent 12 weeks. The mean (+/-SD) health perception scores were 0.43 +/- 0.31 and 0.68 +/- 0.20 in patients with and without events, respectively (P =.0006). The risk ratio (RR) for an event associated with a decile change in the health perception score was 0.74 (95% confidence interval [CI], 0.61-0.88; P =.001). The RR was unaltered by adjustment for demographic variables, treadmill time, and NYHA functional class. Although the week 12 NYHA functional class was predictive of events (RR = 2.1; 95% CI, 1.2-4.6; P =.04), treadmill time was not (RR = 0.87; 95% CI, 0.73-1.03; P = 0.11). CONCLUSIONS: A patient-reported measure of perceived health predicts events in patients with heart failure.


Subject(s)
Health Status , Heart Failure/diagnosis , Heart Failure/physiopathology , Aged , Emergency Service, Hospital , Female , Heart Failure/mortality , Hospitalization , Humans , Male , Middle Aged , Pain Measurement , Prognosis , Time Factors
19.
Am J Physiol Heart Circ Physiol ; 281(1): H275-83, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11406494

ABSTRACT

In the serum of 116 healthy individuals, exogenous bradykinin (BK) half-life (27 +/- 10 s) was lower than that of des-Arg(9)-BK (643 +/- 436 s) and was statistically different in men compared with women. The potentiating effect of an angiotensin-converting enzyme (ACE) inhibitor was, however, more extensive for BK (9.0-fold) than for des-Arg(9)-BK (2.2- fold). The activities of ACE, aminopeptidase P (APP), and kininase I were respectively 44 +/- 12, 22 +/- 9, and 62 +/- 10 nmol x min(-1) x ml(-1). A mathematical model (y = kt(alpha)e(-beta t), t > 0), applied to the BK kinetically released from endogenous high-molecular-weight kininogen (HK) during plasma activation in the presence of an ACE inhibitor, revealed a significant difference in the rate of formation of BK between men and women. For des-Arg(9)-BK, the active metabolite of BK, the rate of degradation was higher in women compared with men, correlating significantly with serum APP activity (r(2) = 0.6485, P < 0.001). In conclusion, these results constitute a basis for future pathophysiological studies of inflammatory processes where activation of the contact system of plasma and the kinins is involved.


Subject(s)
Bradykinin/analogs & derivatives , Bradykinin/metabolism , Plasma/physiology , Adult , Aged , Bradykinin/blood , Female , Half-Life , Humans , Kinetics , Kinins/metabolism , Lysine Carboxypeptidase/metabolism , Male , Metalloendopeptidases/blood , Middle Aged , Peptidyl-Dipeptidase A/metabolism
20.
Ann Intern Med ; 134(7): 550-60, 2001 Apr 03.
Article in English | MEDLINE | ID: mdl-11281737

ABSTRACT

PURPOSE: Congestive heart failure is an important cause of patient morbidity and mortality. Although several randomized clinical trials have compared beta-blockers with placebo for treatment of congestive heart failure, a meta-analysis quantifying the effect on mortality and morbidity has not been performed recently. DATA SOURCES: The MEDLINE, Cochrane, and Web of Science electronic databases were searched from 1966 to July 2000. References were also identified from bibliographies of pertinent articles. STUDY SELECTION: All randomized clinical trials of beta-blockers versus placebo in chronic stable congestive heart failure were included. DATA EXTRACTION: A specified protocol was followed to extract data on patient characteristics, beta-blocker used, overall mortality, hospitalizations for congestive heart failure, and study quality. DATA SYNTHESIS: A hierarchical random-effects model was used to synthesize the results. A total of 22 trials involving 10 135 patients were identified. There were 624 deaths among 4862 patients randomly assigned to placebo and 444 deaths among 5273 patients assigned to beta-blocker therapy. In these groups, 754 and 540 patients, respectively, required hospitalization for congestive heart failure. The probability that beta-blocker therapy reduced total mortality and hospitalizations for congestive heart failure was almost 100%. The best estimates of these advantages are 3.8 lives saved and 4 fewer hospitalizations per 100 patients treated in the first year after therapy. The probability that these benefits are clinically significant (>2 lives saved or >2 fewer hospitalizations per 100 patients treated) is 99%. Both selective and nonselective agents produced these salutary effects. The results are robust to any reasonable publication bias. CONCLUSIONS: beta-Blocker therapy is associated with clinically meaningful reductions in mortality and morbidity in patients with stable congestive heart failure and should be routinely offered to all patients similar to those included in trials.


Subject(s)
Adrenergic beta-Antagonists/therapeutic use , Heart Failure/drug therapy , Heart Failure/mortality , Bayes Theorem , Hospitalization/statistics & numerical data , Humans , Research Design/standards , Survival Analysis
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