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Bronisław Bednarz

Publications and source records attributed to Bronisław Bednarz.

12 recordsLinked to original sources

Efficacy and safety of oral l-arginine in acute myocardial infarction. Results of the multicenter, randomized, double-blind, placebo-controlled ARAMI pilot trial.

AIMS: L-arginine is a substrate for nitric oxide (NO) synthesis in vascular endothelial cells. NO bioavailability is decreased during myocardial infarction (MI). It might be expected that administration of L-arginine may maintain NO production and alleviate the course of MI. The aim of the study was to assess safety and effects of treatment with L-arginine on the clinical course of MI. METHODS AND RESULTS: 792 patients (mean age 64 years, 551 men) with ST segment elevation MI admitted within 24h after the onset of symptoms were randomized to oral L-arginine (3.0 t.i.d p.o. for 30 days) or placebo on top of routine therapy. The end point which was the composite of 30 day cardiovascular death, reinfarction, successful resuscitation, shock/pulmonary edema or recurrent myocardial ischemia occurred in 24% patients treated with L-arginine and 27% with placebo (OR 0.63, 95% CI 0.39-1.02, p=0.06). The end point was observed less frequently in 226 patients with hyperlipidemia (19 vs 31, p<0.05). No serious adverse effects were observed during L-arginine supplementation. CONCLUSIONS: This study, which is the first attempt to use L-arginine in MI, showed that oral L-arginine supplementation was well tolerated. Beneficial nonsignificant trend was observed towards reduction of major clinical events.

Administration, Oral↗

Antioxidant effects of combined vitamins C and E in acute myocardial infarction. The randomized, double-blind, placebo controlled, multicenter pilot Myocardial Infarction and VITamins (MIVIT) trial.

AIMS: There is a large body of evidence that reactive oxygen species (ROS) produced during myocardial ischemia and reperfusion play a crucial role in myocardial damage and endothelial dysfunction. The MIVIT pilot trial was designed to test the effects of antioxidant vitamins C and E on the clinical outcome of patients with AMI. METHODS AND RESULTS: In this randomized, double-blind, multicenter trial, 800 patients (mean age 62) with AMI were randomly allocated to receive, on top of routine medication, one of two treatments: vitamin C (1000 mg/12 h infusion) followed by 1200 mg/24 h orally and vitamin E (600 mg/24 h) or matching placebo for 30 days. Primary end point (composite of in-hospital cardiac mortality, non-fatal new myocardial infarction, VT/VF/asystole, shock/pulmonary edema) occurred less frequently in patients treated with antioxidants (55 [14%] vs 75 [19%], OR 0.82 [95% CI, 0.68-1.00], p=0.048). CONCLUSIONS: This randomized pilot trial shows that supplementation with antioxidant vitamins is safe and seems to positively influence the clinical outcome of patients with AMI. A larger study is warranted to provide further evidence of this promising and inexpensive regimen.

Adult↗

Lipid profile during the first 24 hours after myocardial infarction has significant prognostic value.

AIMS: A high level of total cholesterol and LDL-cholesterol disturbs the endothelial function. Thus it can be expected, that hypercholesterolaemia may unfavourably influence the course of the acute myocardial infarction. The aim of the study was to check whether patients with lipid levels above normal during the first hours of myocardial infarction have an unfavourable clinical outcome. METHODS AND RESULTS: The study group consisted of 348 patients (216 males, aged 65.7+/-12 years) with acute myocardial infarction hospitalized up to 24 hours after the onset of symptoms. Blood samples for lipid profile were taken on the first day of hospitalization, in the morning, while fasting. 109 (31%) patients had a complicated in-hospital course of infarction (i.e. death, recurrent ischaemia, serious arrhythmias and/or conduction disturbances, heart failure). The total cholesterol and LDL-cholesterol levels were higher in the patients with complicated than in the patients with uncomplicated clinical course of infarction: 243+/-40.7 vs 211.2+/-40.6 mg/dl, p<0.001 and 156+/-35.0 vs 132.6+/-35.2 mg/dl p<0.001, respectively. CONCLUSIONS: Higher levels of total cholesterol and LDL cholesterol during the first 24 hours of acute myocardial infarction have a strong negative prognostic value, what suggests the use of statins as early as possible in acute myocardial infarction.

Adult↗

L-arginine supplementation prolongs exercise capacity in congestive heart failure.

BACKGROUND: In congestive heart failure (CHF), endothelial dysfunction may contribute to impairment of exercise induced vasodilatation and decreased exercise capacity. We hypothesised that administration of L-arginine, a precursor of nitric oxide (NO) and postulated antioxidant, may improve endothelium-dependent vasodilatation and exercise capacity and also exert antioxidant activity. AIMS: To investigate the effect of oral supplementation with L-arginine on exercise capacity and markers of oxidative stress in patients with mild to moderate CHF. METHODS: The study had a randomised double-blind cross-over design. Twenty one patients with stable NYHA II-III CHF underwent three exercise tests: initially, after oral administration of L-arginine (9 g/day for 7 days) or placebo. Blood was sampled prior to each test for plasma lipid peroxides, reduced sulphydryl groups and leukocyte oxygen free radical production. RESULTS: We found a higher prolongation of exercise duration time after L-arginine than after placebo (99+/-106 vs 70+/-99 s, p<0.05). There were no significant differences in markers of free radical activity. CONCLUSIONS: In patients with chronic stable CHF, oral supplementation with L-arginine prolongs exercise duration which may be due to NO-induced peripheral vasodilatation. The antioxidant properties of L-arginine have not been confirmed in this ex vivo study.

Aged↗

Prognostic value of exercise-induced QT dispersion in patients after acute myocardial infarction.

BACKGROUND: Electrocardiographic exercise tests are widely recommended for patients before discharge after myocardial infarction, what justify the search for new variables which may improve their prognostic value. QT dispersion in 12 lead ECG reflects the heterogeneity of ventricular repolarisation. Increased QT dispersion is a noninvasive marker of ischaemia and electrical instability. AIM: Evaluation of the prognostic value of exercise-induced changes of QT dispersion in patients after an acute myocardial infarction. METHODS: Heart rate limited treadmill exercise test according to modified Bruce was performed 14+/-5 days after infarction in 77 patients (age 56+/-11,8 female). QT dispersion was measured at rest and on peak exercise. Patients were followed up for mean 88 months. RESULTS: QT dispersion was higher at peak exercise in those patients who died due to cardiovascular causes (n=8) or suffered from non-fatal myocardial infarction during follow-up (n=15), than in remaining group (71+/-20 vs 58+/-22 msec, p<0.01). At rest QT dispersion was similar in both groups (64+/-17 vs 66+/-20 msec, NS). CONCLUSIONS: The lack of an exercise-induced decrease in QT dispersion identifies a subgroup of patients after myocardial infarction with a poor long-term prognosis.

Aged↗

[Effects of statins on coronary artery disease. Review of the recent publications].

This review describes the role of statins in the primary and secondary prevention of coronary artery disease and the clinical benefit of therapy with statins in different forms of coronary artery disease (stable, unstable and myocardial infarction). Presented clinical trials have provided data that statins not only reduce plasma total cholesterol and LDL-cholesterol levels but also reduce major coronary event rate and all-cause mortality. Treatment with statins is usually well tolerated. The mean total cost of care to reach LDL-cholesterol target is significantly lower with atorvastatin than with the other statins.

Anticholesteremic Agents↗

Antioxidant vitamins decrease exercise-induced QT dispersion after myocardial infarction.

BACKGROUND: Antioxidant vitamins C and E inhibit neutrophil-mediated production of free radicals in acute myocardial infarction (MI) which may limit MI size and improve myocardial perfusion. AIM: To examine whether treatment with vitamin C and E reduces inhomogeneity of repolarisation in patients with acute MI. METHODS: In this double-blind, placebo-controlled randomised trial 37 patients with acute MI were enrolled and assigned to vitamin C and E (600 mg/day each) or placebo treatment, starting on the first day of acute MI and lasting for 14 days. Inhomogeneity of repolarisation was assessed by examining QT interval dispersion (QTd), measured both at rest and at the end of sub-maximal exercise test, performed before discharge. RESULTS: Baseline QTd was similar in both groups, however, exercise-induced QTd was significantly lower in patients treated with antioxidant vitamins compared with the placebo group (59 +/- 20 msec vs 74 +/- 24 msec, p<0.05).

Antioxidants↗

Is preinfarction angina associated with better outcome after myocardial infarction?

BACKGROUND: In a clinical setting of acute myocardial infarction (MI), short-lasting and transient anginal pain, preceding the development of acute MI, is regarded as a symptom representing ischaemic preconditioning. Some experimental and clinical data suggested that preinfarction angina may favourably influence the course of acute MI. AIM: We sought to examine the hypothesis that preinfarction angina occurring within 24 hours prior to the onset of acute MI favourably influences the outcome. METHODS: The study group consisted of 331 patients who were admitted to our hospital due to acute MI with ST segment elevation with a symptom duration <12 hours and received thrombolysis. Preinfarction angina within 24 hours prior to MI was present in 80 patients whereas the remaining 251 patients had no chest pain preceding acute MI. The course of the in-hospital phase of MI (mean 15 days) was analysed. RESULTS: In patients with preinfarction angina the in-hospital complication rate was significantly lower than in patients without angina preceding acute MI (p<0.001). Patients without preinfarction angina more frequently developed heart failure (p<0.001) or died (p<0.01) in hospital. Patients with preinfarction angina had significantly less extensive MI and had reperfusion symptoms more frequently. Multivariate analysis showed that there were three factors which independently favourably influenced survival: preinfarction angina (p=0.01), age < or =65 years (p=0.04) and duration of chest pain during acute MI < or =3h (p=0.03). Of the analysed group, 73 patients died in hospital. The independent variables predicting death included prior MI (p=0.04), history of diabetes (p=0.02), acute left bundle branch block (p=0.01) and age >65 years (p=0.03). Non-fatal re-infarction complicated the in-hospital course of MI in 27 patients. The independent variables which predicted this complication included age >65 years (p=0.03) and hypercholesterolemia (p=0.04). CONCLUSIONS: Patients with preinfarction angina, occurring within 24 hours of acute MI, have better in-hospital outcome and less extensive myocardial injury than patients without antecedent angina. These results may be attributed to the protective effects of ischaemic preconditioning.

Adrenergic beta-Antagonists↗

Acute coronary syndrome: potassium, magnesium and cardiac arrhythmia.

BACKGROUND: Cardiac arrhythmia is often present in patients with acute coronary syndrome (ACS) and may be due to the electrolyte imbalance. AIM: To assess the prevalence and clinical significance of electrolyte imbalance in ACS. METHODS: Serum potassium and magnesium levels were measured within the first few hours in 204 consecutive patients with ACS admitted to our department over a period of 23 months. Cardiac arrhythmia was documented using continuous ECG monitoring, telemetry or standard ECG. RESULTS: Hypokalemia was observed in 34% of patients, and was significantly associated with the occurrence of life-threatening ventricular arrhythmias (26% of patients with potassium level <4 mmol/l vs 11.9% of patients with normokalemia, p<0.001). No relationship was found between potassium level and supraventricular arrhythmias or in-hospital mortality. Decreased magnesium serum concentration was found in 22% of patients but was not significantly associated with cardiac arrhythmias or mortality. CONCLUSIONS: Hypokalemia and hypomagnesemia are often present in patients with ACS. The former is associated with dangerous ventricular arrhythmias. Early assessment of electrolyte serum concentration is needed in order to implement proper supplementation.

Acute Disease↗

Is chest pain still the most important symptom of acute coronary syndrome?

BACKGROUND: Acute coronary syndrome (ACS) carries the risk of death due to electrical or haemodynamical disturbances. Thus, rapid in-hospital treatment is necessary. To achieve this, a patient, his family and his physician should correctly diagnose ACS, based mainly on clinical symptoms. AIM: To assess the symptomatology of ACS and to establish whether modern management of ischaemic heart disease did not change ACS clinical characteristics. METHODS: The study group consisted of 156 consecutive patients (96 males, mean age 65+/-15 years) admitted to hospital due to ACS. Physicians prospectively filled in a questionnaire addressing ACS symptomatology, including chest pain characteristics and clinical symptoms of painless ACS. RESULTS: Retrosternal chest pain was present in 119 (76%) patients, six (4%) patients had pain localised outside thorax (jaws or epigastric region) whereas 31 (20%) patients had painless ACS. In the latter group the most frequent symptoms were dyspnea and marked weakness. CONCLUSIONS: Chest pain remains the most frequent symptom of ACS and its prevalence is similar to that previously described in literature. Almost a quarter of patients have painless ACS; in those patients other intensive and sudden symptoms may suggest ACS.

Journal Article↗