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W H van Gilst

Publications and source records attributed to W H van Gilst.

At least 19 recordsLinked to original sources

Effects of quinapril on clinical outcome after coronary artery bypass grafting (The QUO VADIS Study). QUinapril on Vascular Ace and Determinants of Ischemia.

The QUO VADIS study was designed to explore whether 1 year of angiotensin-converting enzyme inhibition with quinapril (40 mg/day) would decrease ischemia in patients who underwent coronary artery bypass grafting (CABG). Patients (n = 149) scheduled for CABG were randomized 4 weeks before surgery. Study medication was used from randomization up to 1 year after CABG. Exercise testing was performed at randomization; the exercise test was repeated 1 year after CABG and patients underwent 48-hour Holter monitoring. Clinical ischemic events were recorded and defined as death, revascularization, myocardial infarction, recurrence of angina pectoris, ischemic stroke, or transient ischemic attack. Baseline characteristics were similar between groups. Total exercise time increased overall by 75 +/- 76 seconds 1 year after CABG (placebo +79 +/- 75 seconds, quinapril +72 +/- 79 seconds, p = 0.6). All patients had ischemic ST-segment changes at randomization; 33% of patients had ischemic ST-segment changes 1 year after CABG (placebo 29%, quinapril 37%, p = 0.4). On Holter monitoring, the number of patients experiencing > or = 1 episodes of ischemia was equal in both groups. Treatment with quinapril significantly reduced clinical ischemic events after CABG: 15% in patients on placebo versus 4% of patients on quinapril (hazard ratio 0.23, 95% confidence interval 0.06 to 0.87, p = 0.02). Long-term quinapril treatment significantly reduced clinical ischemic events within 1 year after CABG, although ischemia at exercise testing and Holter monitoring was unchanged.

Aftercare↗

[Hormonal supplement therapy in women: effects on the cardiovascular system].

Coronary heart disease develops on average 10-15 years later in women than in men and is uncommon before menopause. 17 beta-estradiol has atheroprotective properties through rapid vasodilatory effects on the endothelium by stimulating nitric monoxide production and longer-term actions by modulating changes in gene expression. Cardioprotective effects of hormone replacement therapy in postmenopausal women have been suggested by observational data but not proved in randomized trials. Recent data indicate that oestrogens have regenerative effects on the vascular wall after acute injury, like a percutaneous transluminal coronary angioplasty. As endothelial reactivity declines with age, more studies are needed to investigate the benefits of hormone replacement therapy in the younger category of postmenopausal women.

Age Factors↗

Early expression of natriuretic peptides and SERCA in mild heart failure: association with severity of the disease.

BACKGROUND: We investigated changes in genetic expression of atrial and brain natriuretic peptides (ANP and BNP) and sarcoplasmic reticulum Ca(2+)-ATPase (SERCA) in patients with stable mild to moderate chronic heart failure (CHF), since data on this topic were primarily obtained in end-stage CHF. METHODS: We studied tissue from 25 patients with idiopathic dilated cardiomyopathy (IDC) in New York Heart Association (NYHA) class II (n=12) and III-IV (n=13). Myocardial tissue from normal hearts (n=10) served as controls. Messenger RNA (mRNA) expression of ANP, BNP, and SERCA was isolated, and correlated with severity of CHF, left ventricular function (LVEF), peak oxygen uptake (peak VO(2)), and wedge pressure. RESULTS: A significant trend for gradual changes in mRNA expression according to increasing NYHA class was found for ANP, BNP (P<0.0001) and SERCA (P=0.04), with a marked increase in patients with more advanced CHF (ANP and BNP: P<0.01 vs. controls; SERCA: NS) and less pronounced changes in patients with mild CHF. mRNA of ANP and BNP correlated strongly with LVEF (-0.621 and -0.621, respectively, both P<0.01) and peak VO(2) (-0.625 and -0.555, respectively, both P<0.01) and, to a lesser extent, with wedge pressure (0.440 and 0.488, respectively, both P<0.05). SERCA correlated most strongly with wedge pressure (-0.623, P<0.01), and weak, non-significant correlations with LVEF and peak VO(2) were found. CONCLUSIONS: Genetic expression of ANP, BNP, and SERCA is progressively altered in proportion to the severity of CHF, although this is more marked for ANP and to a lesser extent BNP, than for SERCA. These changes support the concept that already early in CHF, genetic expression is affected, which has implications for the understanding of the pathophysiology of CHF.

Adult↗

Reduction of exercise-induced myocardial ischemia during add-on treatment with the angiotensin-converting enzyme inhibitor enalapril in patients with normal left ventricular function and optimal beta blockade.

OBJECTIVES: We sought to study the effect of angiotensin-converting enzyme inhibition on exercise-induced myocardial ischemia. BACKGROUND: Although angiotensin-converting enzyme inhibitors have been shown to reduce ischemic events after myocardial infarction, few data are available regarding their direct anti-ischemic effects in patients with coronary artery disease. METHODS: We studied 43 patients (average age 63 +/- 8 years) with exercise-induced myocardial ischemia (> or =0.1 mV ST depression, despite optimal beta blockade) and normal left ventricular function (ejection fraction >0.50). In a double-blind, placebo-controlled parallel design, patients were treated with angiotensin-converting enzyme inhibitor (enalapril 10 mg twice daily) or placebo. Assessments were made after three weeks (short-term) and 12 weeks (long-term). RESULTS: At baseline, the groups were well matched for all clinical characteristics. After three weeks, there was a slight but not significant increase in time to 0.1 mV ST depression in both groups (p = NS); rate pressure product (RPP = heart rate x systolic blood pressure) was also unaffected. After 12 weeks, however, time to 0.1 mV ST depression further increased in the enalapril group (5.6 +/- 1.9 min) but was unchanged in the placebo group (4.4 +/- 1.3 min; p < 0.05 between groups). In contrast, RPP was not affected. Concentrations of both atrial and brain natriuretic peptides at peak exercise tended to be lower by enalapril, if compared to placebo (p = NS). CONCLUSIONS: Angiotensin-converting enzyme inhibition may reduce exercise-induced myocardial ischemia in patients with normal left ventricular function. Further studies are needed to elucidate the mechanisms involved.

Adolescent↗

Increased risk for ischaemic events is related to combined RAS polymorphism.

OBJECTIVE: To determine whether the angiotensin converting enzyme (ACE) and the angiotensin II type 1 receptor (AT(1)R A1166C) gene polymorphism interact to increase the risk of ischaemic events, and whether this can be explained by the progression of angiographically defined coronary atherosclerosis. DESIGN: Prospective defined substudy of the lipid lowering regression trial (REGRESS). SETTING: University hospital. PATIENTS: 885 male patients with stable coronary artery disease. MAIN OUTCOME MEASURES: Incidence of ischaemic events during a two year follow up; serial quantitative coronary arteriography (mean segment diameter and minimum obstruction diameter) at baseline and after two years. RESULTS: Patients who carried both the ACE-DD and AT(1)R-CC genotype had significantly more ischaemic events during the two year follow up than those carrying other genotype combinations (p = 0.035, Mantel-Haenszel test for linear association). There was no association between the two genotypes and mean segment diameter or minimum obstruction diameter at baseline or after two years. CONCLUSIONS: The suggestion that ACE-DD and AT(1)R-CC genotypes interact to increase the risk of ischaemic events is confirmed. However, this increased risk was not accompanied by increased progression of angiographically defined coronary atherosclerosis.

Coronary Angiography↗

Rationale, design, and baseline characteristics of a trial of prevention of cardiovascular and renal disease with fosinopril and pravastatin in nonhypertensive, nonhypercholesterolemic subjects with microalbuminuria (the Prevention of REnal and Vascular ENdstage Disease Intervention Trial [PREVEND IT]).

This study describes the rationale, design, and baseline characteristics of a trial to determine whether treatment with fosinopril 20 mg/day and/or pravastatin 40 mg/ day will prevent cardiovascular and renal disease in nonhypertensive (RR <160/100 mm Hg and not using antihypertensive medication) and nonhypercholesterolemic (total cholesterol <8.0 or <5.0 mmol/L in case of previous myocardial infarction and not using lipid lowering medication) men and women with persistent microalbuminuria (urinary albumin excretion >10 mg/L once in an early morning spot urine and 15 to 300 mg/24-hour at least once in two 24-hour urine collections). The Prevention of REnal and Vascular ENdstage Disease Intervention Trial is a single-center, double-blind, randomized, placebo-controlled trial with a 2 x 2 factorial design. The 864 randomized subjects will be monitored for a minimum of 4 years and a maximum of 5 years. The primary efficacy parameter is defined as the combined incidence of all-cause mortality or hospital admission for documented (1) nonfatal myocardial infarction, (2) myocardial ischemia, (3) heart failure, (4) peripheral vascular disease, (5) cerebrovascular accident and/or (6) end-stage renal disease.

Adult↗

Diltiazem in acute myocardial infarction treated with thrombolytic agents: a randomised placebo-controlled trial. Incomplete Infarction Trial of European Research Collaborators Evaluating Prognosis post-Thrombolysis (INTERCEPT)

BACKGROUND: Diltiazem reduces non-fatal reinfarction and refractory ischaemia after non-Q-wave myocardial infarction, an acute coronary syndrome similar to the incomplete infarction that occurs after successful reperfusion. We postulated that this agent would reduce cardiac events in patients after acute myocardial infarction treated initially with thrombolytic agents-a clinical application previously unexplored with heart-rate-lowering calcium antagonists. METHODS: A prospective, randomised, double-blind, sequential trial was done in 874 patients with acute myocardial infarction, but without congestive heart failure, who first received thrombolytic agents. Patients received either 300 mg oral diltiazem once daily, or placebo, initiated within 36-96 h of infarct onset, and given for up to 6 months. The trial primary endpoint was the cumulative first event rate of cardiac death, non-fatal reinfarction, or refractory ischaemia. Additional prespecified endpoints included several composites of non-fatal cardiac events (non-fatal reinfarction combined with refractory ischaemia, all recurrent ischaemia, or the need for myocardial revascularisation). The diagnosis of ischaemia, whether refractory or recurrent, and the need for myocardial revascularisation, was always based on objective electrocardiographical evidence of ischaemia, either at rest or on exertion. RESULTS: For the trial primary endpoint, 131 events occurred in the 444 placebo patients and 97 events in the 430 diltiazem patients (hazard ratio 0.79; 95% CI, 0.61-1.02; p=0.07). For non-fatal cardiac events, diltiazem treatment was associated with a relative decrease (0.76; 0.58-1.00) in the combined event rate of non-fatal reinfarction and refractory ischaemia. There was a similar decrease in the composite non-fatal endpoints of non-fatal reinfarction combined with all recurrent ischaemia (0.80; 0.64-1.00) and non-fatal reinfarction combined with the need for myocardial revascularisation (0.67; 0.46-0.96). The need for myocardial revascularisation alone was significantly reduced by 42% (0.61; 0.39-0.96). No major safety issues were encountered. CONCLUSIONS: Diltiazem did not reduce the cumulative occurrence of cardiac death, non-fatal reinfarction, or refractory ischaemia during a 6-month follow-up, but did reduce all composite endpoints of non-fatal cardiac events, especially the need for myocardial revascularisation.

Calcium Channel Blockers↗

Chronic beta-blocker treatment in patients with advanced heart failure. Effects on neurohormones.

BACKGROUND: To date, the use of beta-blockers in treating patients with chronic heart failure gains support, this since several large clinical trials reported reduced mortality after chronic beta-blockade. Part of these beneficial effects may result from inhibition of deleterious neurohormone activation that accompanies progression of chronic heart failure. The present study evaluates whether this neurohormone inhibition is preserved after chronic beta-blockade. METHODS: In a retrospective analysis the neurohormonal profiles of patients with moderate to severe chronic heart failure were studied from three treatment subgroups: (1) Without beta-blockers or ACE-inhibitors (n=15), (2) without beta-blockers, with ACE-inhibitors (n=324), (3) with beta-blockers and ACE-inhibitors (n=31). Patients were on beta-blockers for an average period of 3.8 years. Plasma samples were obtained under controlled conditions. RESULTS: Despite uneven group sizes, the groups were well matched for clinical characteristics. Plasma renin levels were significantly lower in patients treated adjunctively with beta-blockers. Plasma aldosterone and endothelin-I levels also tended to be lower after chronic beta-blockade, however, this did not reach statistical significance. CONCLUSIONS: Chronic adjunctive beta-blocker treatment shows significantly lower plasma renin levels when compared to single ACE-inhibition. This persistent reduction of plasma neurohormone activation may concomitantly reduce the chance of neurohormones to escape from inhibition.

Adrenergic beta-Antagonists↗

Beta-blocker titration failure is independent of severity of heart failure.

In the present study, predictors of complicated initiation of beta blockade in patients with idiopathic dilated cardiomyopathy was studied. We found that generally accepted measures of severity of heart failure are not predictable, whereas low systolic blood pressure (< or =120 mm Hg) was the strongest predictor for problematic (up)titration.

Adolescent↗

Beta-adrenoceptor density in chronic infarcted myocardium: a subtype specific decrease of beta1-adrenoceptor density.

UNLABELLED: Beta-adrenoceptor density is altered in different cardiac diseases. In heart failure beta-adrenoceptor density is down regulated but in acute myocardial ischemia beta-adrenoceptor density is up regulated. In hearts with myocardial infarction total beta-adrenoceptor density is decreased shortly after myocardial infarction. AIMS AND METHODS: To investigate whether total beta-adrenoceptor number is altered in the chronic phase after myocardial infarction, and to identify the specificity of alteration, we studied male Wistar rats (n = 18) which underwent a ligation of the left coronary artery or a sham operation. Twelve weeks after coronary ligation, rats were sacrificed and hearts were excised, perfused to obtain blood-free myocardium and frozen in liquid nitrogen. Infarcted myocardium was identified visually and separated from non-infarcted myocardium. Total beta-adrenoceptor number was calculated in fmol (-)-[125I]iodocyanopindolol specifically bound/mg protein and the relative amount of beta1- and beta2-adrenoceptor density was measured by inhibition of (-)-[125I]iodocyanopindolol binding with CGP 20712 A. RESULTS: Total beta-adrenoceptor number in infarcted myocardium was significantly decreased (25.7+/-1.4 vs. 24.9+/-2.2 vs. 20.1+/-3.2 fmol/mg protein (P=0.03) resp. Sham vs. Non-infarcted vs. Infarcted myocardium), due to a decrease of only beta1-adrenoceptor density (14.7+/-0.61 vs. 12.7+/-1.09 vs. 4.84+/-0.96 fmol/mg protein (P=0.004) resp.), whereas the beta2-adrenoceptor density and the dissociation constant (Kd) were not significantly decreased. CONCLUSION: In the infarcted myocardium total beta-adrenoceptor density is decreased due to a decreased beta1-adrenoceptor density at 12 weeks after myocardial infarction.

Animals↗

Direct interaction between the sympathetic and renin-angiotensin system in myocardial tissue: a microdialysis study in anaesthetised rats.

It has been suggested that local activation of the renin-angiotensin system is involved in early stages of myocardial pathophysiology. To date, there is increasing evidence for interactions between the renin-angiotensin system and the sympathetic nervous system; consequently, local sympathetic activation may also be involved in this. Microdialysis has great potential in the direct investigation of neurohormonal interactions. Therefore, the present study employs microdialysis to study the local effects of exogenous angiotensin II on the interstitial norepinephrine concentration of the normally innervated left ventricle of the anaesthetised rat. The present study investigates the effect of increasing dosages of exogenous angiotensin II on local interstitial norepinephrine. Furthermore, a single dose of losartan was infused on top of the highest dose of angiotensin II, in order to study possible involvement of angiotensin II type 1 (AT1) receptors. Both infusion and sampling were carried out locally, via the microdialysis probes. Concomitantly, circulating norepinephrine levels, heart rate and respiratory rate were monitored to evaluate physiologic stability of the preparation throughout the experiment. Time controls consisted of rats that were perfused with only a Ringer's solution. Angiotensin II induced a dose dependent increase in norepinephrine that was significantly reduced by losartan. Norepinephrine levels in both plasma (infusion experiment and time controls) and the left ventricular wall (time controls) remained stable throughout the experiment, just as heart rate and respiratory rate did. This study for the first time employs microdialysis to demonstrate direct interaction between the sympathetic nervous system and the renin-angiotensin system in the rat left ventricle. The data strongly suggest that AT1 receptors are involved in this interaction, since selective AT1 receptor blockade with losartan significantly reduced the angiotensin II induced norepinephrine concentration.

Angiotensin II↗

Effect of very early angiotensin-converting enzyme inhibition on left ventricular dilation after myocardial infarction in patients receiving thrombolysis: results of a meta-analysis of 845 patients. FAMIS, CAPTIN and CATS Investigators.

OBJECTIVES: We sought to investigate the effect of angiotensin-converting enzyme (ACE) inhibition <9 h after myocardial infarction (MI) on left ventricular (LV) dilation in patients receiving thrombolysis. BACKGROUND: The ACE inhibitors reduce mortality after MI. Attenuation of LV dilation has been suggested as an important mechanism. METHODS: The data of 845 patients with three-month echocardiographic follow-up after MI were combined from three randomized, double-blind, placebo-controlled studies. The criteria for these studies included: 1) thrombolytic therapy; 2) ACE inhibition within 6 to 9 h; and 3) evaluation of LV dilation as the primary objective. RESULTS: The ACE inhibitor was started 3.2+/-1.7 h after the patients' first (mainly, 85%) anterior MI. After three months, LV dilation was not significantly attenuated by very early treatment with an ACE inhibitor. The diastolic volume index was attenuated by 0.5 ml/m2 (95% confidence interval [CI] -1.5 to 2.5, p = 0.61), and the systolic volume index by 0.5 ml/m2 (95% CI -1.0 to 1.9, p = 0.50). Subgroup analysis demonstrated that LV dilation was significantly attenuated by ACE inhibitor treatment for patients in whom reperfusion failed. In contrast, LV dilation was almost unaffected by ACE inhibitor treatment in successfully reperfused patients. CONCLUSIONS: We could not demonstrate attenuation of LV dilation in patients receiving thrombolysis by ACE inhibitor treatment within 6 to 9 h after MI. We speculate that very early treatment with an ACE inhibitor has a beneficial effect on LV remodeling only in patients in whom reperfusion failed. Other mechanisms may be responsible for the beneficial effects of ACE inhibitors in successfully reperfused patients after MI.

Angiotensin-Converting Enzyme Inhibitors↗

Regional myocardial blood flow reserve impairment and metabolic changes suggesting myocardial ischemia in patients with idiopathic dilated cardiomyopathy.

OBJECTIVES: We performed positron emission tomography (PET) to evaluate myocardial ischemia in patients with idiopathic dilated cardiomyopathy (IDC). BACKGROUND: Patients with IDC have anatomically normal coronary arteries, and it has been assumed that myocardial ischemia does not occur. METHODS: We studied 22 patients with IDC and 22 control subjects using PET with nitrogen-13 ammonia to measure myocardial blood flow (MBF) at rest and during dipyridamole-induced hyperemia. To investigate glucose metabolism, fluorine-18 deoxyglucose (18FDG) was used. For imaging of oxygen consumption, carbon-11 acetate clearance rate constants (k(mono)) were assessed at rest and during submaximal dobutamine infusion (20 microg/kg body weight per min). RESULTS: Global MBF reserve (dipyridamole-induced) was impaired in patients with IDC versus control subjects (1.7 +/- 0.21 vs. 2.7 +/- 0.10, p < 0.05). In patients with IDC, MBF reserve correlated with left ventricular (LV) systolic wall stress (r = -0.61, p = 0.01). Furthermore, in 16 of 22 patients with IDC (derived by dipyridamole perfusion) mismatch (decreased flow/increased 18FDG uptake) was observed in 17 +/- 8% of the myocardium. The extent of mismatch correlated with LV systolic wall stress (r = 0.64, p = 0.02). The MBF reserve was lower in the mismatch regions than in the normal regions (1.58 +/- 0.13 vs. 1.90 +/- 0.18, p < 0.05). During dobutamine infusion k(mono) was higher in the mismatch regions than in the normal regions (0.104 +/- 0.017 vs. 0.087 +/- 0.016 min(-1), p < 0.05). In the mismatch regions 18FDG uptake correlated negatively with rest k(mono) (r = -0.65, p < 0.05), suggesting a switch from aerobic to anaerobic metabolism. CONCLUSIONS: Patients with IDC have a decreased MBF reserve. In addition, low MBF reserve was paralleled by high LV systolic wall stress. These global observations were associated with substantial myocardial mismatch areas showing the lowest MBF reserves. In geographically identical regions an abnormal oxygen consumption pattern was seen together with a switch from aerobic to anaerobic metabolism. These data support the notion that regional myocardial ischemia plays a role in IDC.

Adult↗

The Euro Heart Failure Survey of the EUROHEART survey programme. A survey on the quality of care among patients with heart failure in Europe. The Study Group on Diagnosis of the Working Group on Heart Failure of the European Society of Cardiology. The Medicines Evaluation Group Centre for Health Economics University of York.

BACKGROUND: The EUROHEART programme is a rolling programme of cardiovascular surveys among the member nations of the European Society of Cardiology (ESC). These surveys will provide information on the nature of cardiovascular disease and its management. This manuscript describes a survey into the nature and management of heart failure. AIMS: The EuroHeart Failure survey aims to describe the quality of hospital care, diagnostic and therapeutic, for patients with suspected or confirmed heart failure in ESC member countries. Patients will be interviewed subsequent to hospital discharge to assess their understanding of their condition, side effects from and their compliance with therapy and their satisfaction with the management for heart failure. The quality of management will be judged against the recommendations contained in the ESC guidelines on diagnosis and treatment of heart failure. Outcome will be further assessed by repeat interviews in 6-12 months time. A further survey of heart failure in 2001/2002 is also planned. METHODS: A prospective survey of all deaths and discharges from medical (cardiology, internal medicine and geriatric medicine) and cardiac surgical wards to identify patients with heart failure, suspected or confirmed. Approximately 70 hospital clusters, comprising two to six hospitals in each cluster, in 24 member countries of the ESC are conducting the study. At the time of writing, approximately 30000 deaths and discharges have been screened and approximately 4000 patients have been enrolled. CONCLUSIONS: The EuroHeart Survey will allow actual practice to be compared to ESC guidelines on the diagnosis and treatment of heart failure. The surveys and guidelines should prove mutually informative. The main EuroHeart Failure project will be completed by late 2000. However, new centres volunteering to participate in the study (contact corresponding author) may be accepted providing they have the necessary research personnel and provided funding can be agreed for statistical support and administration.

Angiotensin-Converting Enzyme Inhibitors↗

Angiotensin II formation in human vasculature after chronic ACE inhibition: a prospective, randomized, placebo-controlled study. QUO VADIS Investigators.

The QUO VADIS (the effects of QUinapril On Vascular Ace and Determinants of ISchemia) study was a randomized, double-blind, placebo-controlled trial designed to evaluate the effects of long-term angiotensin-converting enzyme (ACE) inhibition on angiotensin II formation in human vasculature. Patients (n = 187) scheduled for coronary artery bypass surgery used study medication 27 +/- 1 days before surgery. Segments of internal mammary arteries were exposed to increasing doses (0.1 nM-1 microM) of angiotensin I and II in organ baths. The rate of local angiotensin II formation is a function of the reciprocal of the difference between the pEC50's of the dose response curves to angiotensin I and II (-log/mol) and of the area between the curves (units). Quinapril (40 mg) and captopril (3 x 50 mg) similarly and significantly reduced mean blood pressure compared with placebo (p = 0.04). Difference between pEC50's was 0.90 +/- 0.08 in quinapril patients compared with 0.60 +/- 0.08 for placebo (p = 0.01); the area between curves was 91 +/- 8 for quinapril patients compared with 67 +/- 8 for placebo (p = 0.03). Angiotensin II formation was decreased to a lesser extent with captopril and was not statistically different from placebo (p = 0.3); the difference between pEC50's was 0.83 +/- 0.15; the area between curves was 84 +/- 12. This is the first randomized study to demonstrate that long-term oral treatment with an ACE inhibitor reduces vascular angiotensin II formation in humans.

Administration, Oral↗

Comparison of zofenopril and lisinopril to study the role of the sulfhydryl-group in improvement of endothelial dysfunction with ACE-inhibitors in experimental heart failure.

We evaluated the role of SH-groups in improvement of endothelial dysfunction with ACE-inhibitors in experimental heart failure. To this end, we compared the vasoprotective effect of chronic treatment with zofenopril (plus SH-group) versus lisinopril (no SH-group), or N-acetylcysteine (only SH-group) in myocardial infarcted (MI) heart failure rats. After 11 weeks of treatment, aortas were obtained and studied as ring preparations for endothelium-dependent and -independent dilatation in continuous presence of indomethacin to avoid interference of vasoactive prostanoids, and the selective presence of the NOS-inhibitor L-NMMA to determine NO-contribution. Total dilatation after receptor-dependent stimulation with acetylcholine (ACh) was attenuated (-49%, P<0.05) in untreated MI (n=11), compared to control rats with no-MI (n=8). This was in part due to impaired NO-contribution in MI (-50%, P<0.05 versus no-MI). At the same time the capacity for generation of biologically active NO after receptor-independent stimulation with A23187 remained intact. Chronic treatment with n-acetylcysteine (n=8) selectively restored NO-contribution in total dilatation to ACh. In contrast, both ACE-inhibitors fully normalized total dilatation to ACh, including the part mediated by NO (no significant differences between zofenopril (n=10) and lisinopril (n=8)). Zofenopril, but not lisinopril, additionally potentiated the effect of endogenous NO after A23187-induced release from the endothelium (+100%) as well as that of exogenous NO provided by nitroglycerin (+22%) and sodium nitrite (+36%) (for all P<0.05 versus no-MI). We conclude that ACE-inhibition with a SH-group has a potential advantage in improvement of endothelial dysfunction through increased activity of NO after release from the endothelium into the vessel wall. Furthermore, this is the first study demonstrating the selective normalizing effect of N-actylcysteine on NO-contribution to ACh-induced dilatation in experimental heart failure.

Acetylcholine↗