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Convulsions and loss of consciousness can be caused by, among other things, arrhythmias, conduction disorders or epilepsy. In clinical practice it can be difficult to distinguish between these causes of syncope, even for well-trained specialists. Patients with cardiac syncope have a substantial risk of subsequent sudden death. We present a patient with previously unknown noncompaction cardiomyopathy in whom syncope induced by ventricular tachycardia was misinterpreted as epilepsy. We present this case report in order to underline the necessity for cardiological assessment in patients with assumed mild epilepsy or syncope of unknown origin.
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OBJECTIVE: To determine the efficacy of 2 nurse-directed programmes of different intensity for the counselling and follow-up of patients hospitalised for heart failure, compared with standard care by a cardiologist. DESIGN: Multicentre randomised clinical trial (www.trialregister.nl: NCT 98675639). METHOD: A total of 1023 patients were randomized after hospitalisation for heart failure to 1 of 3 treatment strategies: standard care provided by a cardiologist, follow-up care from a cardiologist with basic counselling and support by a nurse specialising in heart failure, or follow-up care from a cardiologist with intensive counselling and support by a nurse specialising in heart failure. Primary end points were the time to rehospitalisation due to heart failure or death and the number of days lost to rehospitalisation or death during the 18-month study period. Data were analysed on an intent-to-treat basis. RESULTS: Mean patient age was 71 years, 38% were women, 50% had mild heart failure and 50% had severe heart failure. During the study, 411 patients (40%) were rehospitalised due to heart failure or died from any cause: 42% in the control group, and 41% and 38% in the basic and intensive support groups, respectively (differences not significant). The time to rehospitalisation or death was similar in the 3 groups: hazard ratios for the basic and intensive support groups versus the control group were 0.96 (95% CI: 0.76-1.21; p = 0.73) and 0.93 (95% CI: 0.73-1.17; p = 0.53), respectively. The number of days lost to rehospitalisation or death was 39,960 in the control group; this number was 15% less in the intervention groups, but the difference was not significant. However, there was a trend toward lower mortality in the intervention groups. In all 3 groups, more visits occurred than planned, which may have had a considerable effect on care, notably in the control group. CONCLUSION: The results of this study indicated that the provision of additional counselling and support by a nurse specialising in heart failure as an adjuvant to intensive follow-up care provided by a cardiologist does not always lead to a reduction in rehospitalisation frequency.
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Spontaneous coronary artery dissection is a very uncommon cause of acute coronary syndrome. It occurs predominantly in young to middle-aged women during or after pregnancy. The aetiology remains uncertain. Possible factors are hormonal changes, haemodynamic stress and changes in autoimmune status. In case of single-vessel dissection and normal blood flow, conservative treatment often leads to complete angiographic resolution. This case report describes the clinical presentation, diagnosis and therapy of spontaneous coronary artery dissection in a 37-year-old woman in the postpartum period. (Neth Heart J 2008;16:412-4.).
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BACKGROUND/OBJECTIVE: To compare early invasive treatment with continued pharmacological treatment in patients with diabetes mellitus type 2, mild anginal symptoms and documented myocardial ischaemia. METHODS: Patients with type 2 diabetes mellitus and mild anginal symptoms underwent myocardial perfusion scintigraphy (MPS). Patients with myocardial ischaemia were randomly assigned to early invasive or continued pharmacological treatment. All patients were followed for the occurrence of MACE (death, nonfatal myocardial infarction or hospitalisation for unstable angina pectoris). RESULTS: A total of 156 patients were randomised when the sponsor (ZonMW) prematurely terminated the study because of a slow recruitment rate. With a mean follow-up of 2.1±0.6 years, 9 of 79 patients assigned to early invasive treatment developed MACE compared with 10 of 77 patients randomised to continued pharmacological treatment, annual event rate 5.4 vs. 6.3%, hazard ratio 0.89, 95% CI 0.36 to 2.20, p=0.34. Due to the limited number of included patients and the low event rate, the study did not have sufficient power for the study objective. CONCLUSION: Patients with diabetes mellitus type 2, mild anginal symptoms and documented myocardial ischaemia, under appropriate medical treatment, have a lower than anticipated annual event rate of MACE of ±5 to 6% which questions the beneficial effect of early revascularisation.
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OBJECTIVES: We sought to assess the prognostic value of heart rate variability measures, including Poincaré plots, in patients with mild to moderate chronic heart failure. BACKGROUND: Mortality is high in patients with heart failure, and many of them die suddenly. However, identification of high risk patients, particularly those with an increased risk for sudden death, has remained difficult. METHODS: We studied 95 patients with heart failure (mean [+/- SD] age 60 +/- 8 years, left ventricular ejection fraction 0.29 +/- 0.09, New York Heart Association functional class II [81%] and III [19%]) during up to 4 years of follow-up. Heart rate variability measures and Poincaré plots were obtained from 24-h Holter recordings. RESULTS: During follow-up, 17 (18%) of the 95 patients died. In 15 patients, death was cardiac related (11 patients experienced sudden death). None of the conventional time and frequency domain measures of heart rate variability were related to survival. In contrast, abnormal Poincaré plots identified a significantly higher risk for all-cause cardiac death (Cox proportional hazards ratio 5.7, 95% confidence interval [CI] 1.6 to 20.6, univariate analysis) and for sudden cardiac death (hazards ratio 6.8, 95% CI 1.5 to 31.4) compared with those with normal Poincaré plots. Patients with abnormal Poincaré plots were shown to have a lower left ventricular ejection fraction (0.26 +/- 0.10 vs. 0.31 +/- 0.08, p < 0.05) and higher plasma norepinephrine concentrations (506 +/- 207 pg/ml vs. 411 +/- 175 pg/ml, p < 0.05). In multivariate analysis, abnormal Poincaré plots still had independent prognostic value, both for all-cause cardiac mortality and for sudden cardiac death (hazards ratio 5.3, 95% CI 1.2 to 17.1, hazards ratio 4.5, 95% CI 1.0 to 27.5, respectively. CONCLUSIONS: Heart rate variability analysis, as assessed by Poincaré plots, has independent prognostic value in patients with mild to moderate chronic heart failure and identifies an increased risk for all-cause and sudden cardiac death in these patients.
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Gasto Cardíaco Bajo/fisiopatología , Frecuencia Cardíaca , Adolescente , Adulto , Anciano , Gasto Cardíaco Bajo/mortalidad , Muerte , Muerte Súbita Cardíaca , Femenino , Estudios de Seguimiento , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Análisis Multivariante , Norepinefrina/sangre , Pronóstico , Modelos de Riesgos Proporcionales , Volumen Sistólico , Análisis de SupervivenciaRESUMEN
OBJECTIVES: This study assessed the effects of digoxin and ibopamine on variables of heart rate variability in relation to neurohormonal activation. BACKGROUND: Analysis of heart rate variability can be used to study the autonomic dysfunction that characterizes chronic heart failure. In the Dutch Ibopamine Multicenter Trial, patients with heart failure were found to have increased neurohormonal activation with placebo therapy but not with digoxin and ibopamine therapy. METHODS: We studied 59 patients with mild to moderate heart failure (mean [+/- SEM] age 60 +/- 1 years, mean ejection fraction 0.30 +/- 0.01). Patients were randomized to double-blind treatment with digoxin (0.25 mg [n = 22]), ibopamine (100 mg three times a day [n = 19]) or placebo (n = 18); background therapy consisted of furosemide (up to 80 mg). RESULTS: After 3 months, plasma norepinephrine levels had increased with placebo, whereas they decreased with digoxin (+31 vs. -60 pg/ml, respectively, p < 0.01). With ibopamine, nonsignificant decrease was observed (-27 pg/ml, p = 0.10). All variables of heart rate variability showed a deterioration in the placebo group. With digoxin, the percent differences between successive RR intervals > 50 ms (pNN50) increased (+ 1.7 +/- 0.9%, p < 0.01), along with absolute and normalized high frequency power (+ 40 +/- 33 ms2, p < 0.05 and + 2.4 +/- 1.7%, p < 0.01, respectively). These changes were observed during daytime hours only and were most pronounced in patients with the most impaired baseline heart rate variability. With ibopamine, nonsignificant trends similar to the changes with digoxin were observed. CONCLUSIONS: In patients with early stages of heart failure, digoxin may prevent a progressive deterioration in heart rate variability, whereas ibopamine does not show statistically significant effects. The changes in heart rate variability with digoxin parallel an observed decrease in neurohormonal activation. Digoxin apparently enhances cardiac vagal tone in the setting of neuroendocrine activation.
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Cardiotónicos/uso terapéutico , Desoxiepinefrina/análogos & derivados , Digoxina/uso terapéutico , Agonistas de Dopamina/uso terapéutico , Insuficiencia Cardíaca/tratamiento farmacológico , Frecuencia Cardíaca/efectos de los fármacos , Aldosterona/sangre , Desoxiepinefrina/uso terapéutico , Diuréticos/uso terapéutico , Método Doble Ciego , Electrocardiografía Ambulatoria , Femenino , Furosemida/uso terapéutico , Insuficiencia Cardíaca/sangre , Insuficiencia Cardíaca/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Norepinefrina/sangre , Renina/sangre , Factores de TiempoRESUMEN
OBJECTIVES: This study was conducted to test the hypothesis that angiotensin-converting enzyme (ACE) inhibition reduces myocardial ischemia and related events after myocardial infarction (MI). BACKGROUND: The oxygen demand/supply ratio of the myocardium is influenced by angiotensin II as a result of its arterial vasoconstrictive and inotropic effects and through its interaction with the sympathetic nervous system. METHODS: We studied 244 patients who had been included in a double-blind, randomized, placebo-controlled, post-MI, ACE inhibition intervention study (Captopril and Thrombolysis Study [CATS]). All patients underwent exercise testing before and 3 and 12 months after hospital discharge. After 1-year double-blind treatment, all patients continued receiving single-blind placebo for 1 month. RESULTS: Total exercise time increased in both groups after 3 months (placebo: +86 +/- 13 s; captopril: +69 +/- 12 s, p = 0.8 between groups) and increased further after 1 year (placebo: +13 +/- 11 s; captopril: +33 +/- 13 s, p = 0.7 between groups). There were also no differences in mean ST segment depression. During the 12 months, significantly fewer ischemia-related events occurred in the captopril group (82 vs. 52, p = 0.015). This difference was found between 3 and 12 months but not during the first 3 months. After withdrawal from double-blind medication, nine ischemic events were reported in teh captopril group compared with one in the placebo group (p = 0.006 between groups). CONCLUSIONS: The present data show that captopril may reduce the incidence of ischemia-related events after MI, which becomes apparent after 3 months. However, no anti-ischemic effect was observed during exercise testing. After withdrawal from ACE inhibition, a high incidence of clinical events occurred, suggesting a rebound phenomenon.
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Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Captopril/uso terapéutico , Infarto del Miocardio/tratamiento farmacológico , Isquemia Miocárdica/prevención & control , Método Doble Ciego , Tolerancia al Ejercicio , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/fisiopatología , Síndrome de Abstinencia a SustanciasRESUMEN
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.
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Antagonistas Adrenérgicos beta/administración & dosificación , Angina de Pecho/tratamiento farmacológico , Inhibidores de la Enzima Convertidora de Angiotensina/administración & dosificación , Enfermedad Coronaria/tratamiento farmacológico , Enalapril/administración & dosificación , Prueba de Esfuerzo/efectos de los fármacos , Adolescente , Antagonistas Adrenérgicos beta/efectos adversos , Adulto , Anciano , Anciano de 80 o más Años , Inhibidores de la Enzima Convertidora de Angiotensina/efectos adversos , Método Doble Ciego , Quimioterapia Combinada , Electrocardiografía/efectos de los fármacos , Enalapril/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Función Ventricular Izquierda/efectos de los fármacosRESUMEN
OBJECTIVES: This retrospective study sought to assess differences in graft patency and clinical outcome between women and men after coronary artery bypass graft surgery (CABG). BACKGROUND: A less favorable clinical outcome has been reported in women as compared with men. Its relation to graft patency has not been studied. METHODS: We analyzed one-year follow-up data of 912 patients (120 women) who entered a randomized clinical drug trial. All patients received vein grafts; in 494 patients (56 women) internal mammary artery (IMA) grafts were also used. Graft patency was assessed by coronary angiography at one year. Primary clinical end points were myocardial infarction, revascularization procedures and death; secondary clinical end points included recurrent angina, heart failure and arrhythmias. RESULTS: Occlusion rates of vein grafts were 16.7% in women and 12.4% in men (odds ratio [OR] 1.62, 95% confidence interval [CI] 0.88 to 3.00, p = 0.12); occlusion rates of IMA grafts were 3.4% and 5.7% in women and men, respectively (OR 0.56, 95% CI 0.08 to 3.96, p = 0.56). Primary clinical end points were observed in 16.7% of women and 9.2% of men (OR 1.97, 95% CI 1.10 to 3.34, p = 0.022), and any clinical end point in 41.7% of women and 25.8% of men (OR 2.06, 95% CI 1.39 to 3.04, p = 0.0004). Myocardial infarction (15% vs. 7.6%, OR 2.15, 95% CI 1.24 to 3.75, p = 0.013) and recurrent angina (26.7% vs. 15.4%, OR 2.00, 95% CI 1.28 to 3.11, p = 0.004) occurred most frequently. Multivariate regression analysis did not identify gender as an independent risk factor for graft occlusion or the clinical end points. Graft occlusion was an independent predictor of the composite primary clinical end point (OR 2.75, 95% CI 1.59 to 4.75, p = 0.0003) and each of the secondary clinical end points. The observed differences were due to an imbalance of risk factors at baseline and to surgical and graft characteristics. CONCLUSIONS: One-year occlusion rates of vein and IMA grafts were comparable in women and men. Clinical outcome was related to graft patency and was less favorable in women owing to their uneven distribution of risk factors among both groups.
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Puente de Arteria Coronaria , Oclusión de Injerto Vascular/etiología , Anciano , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios Retrospectivos , Factores de Riesgo , Factores Sexuales , Resultado del TratamientoRESUMEN
OBJECTIVES: This study was performed to compare the efficacy and safety of aspirin, aspirin plus dipyridamole, and oral anticoagulant agents in the prevention of internal mammary artery graft occlusion. BACKGROUND: Antithrombotic drugs increase vein graft patency after coronary artery bypass surgery. Their benefit after internal mammary artery grafting has not been established. METHODS: Angiographic internal mammary artery graft patency at 1 year was assessed in 494 patients who received both internal mammary artery and vein grafts. These patients were a subgroup of a prospective, randomized vein graft patency study in 948 patients assigned to treatment with aspirin, aspirin plus dipyridamole, or oral anticoagulant agents. The design was double-blind for both aspirin groups and open for oral anticoagulant treatment. Dipyridamole (5 mg/kg body weight per 24 h intravenously, followed by 200 mg twice daily) and oral anticoagulant agents (prothrombin time target range 2.8 to 4.8 international normalized ratio) were started before operation, and low dose aspirin (50 mg/day) after operation. Clinical outcome was assessed by the incidence of myocardial infarction, thrombosis, major bleeding or death. RESULTS: Occlusion rates of distal anastomoses were 4.6% in the aspirin plus dipyridamole group and 6.8% in the oral anticoagulant group versus 5.3% in the aspirin group (p = NS). Overall clinical event rates were 23.3% and 13.3% in the aspirin plus dipyridamole group and the aspirin group, respectively (relative risk 1.75, 95% confidence interval 1.09 to 2.81, p = 0.025), and 17.1% in the oral anticoagulant group. CONCLUSIONS: Internal mammary artery graft patency at 1 year is not improved by aspirin plus dipyridamole or oral anticoagulant agents over that obtained with low dose aspirin alone. However, there is evidence that the overall clinical event rate increases if dipyridamole is added to aspirin.
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Anticoagulantes/administración & dosificación , Aspirina/administración & dosificación , Dipiridamol/administración & dosificación , Oclusión de Injerto Vascular/prevención & control , Anastomosis Interna Mamario-Coronaria , Acenocumarol/administración & dosificación , Acenocumarol/uso terapéutico , Anticoagulantes/uso terapéutico , Aspirina/uso terapéutico , Dipiridamol/efectos adversos , Dipiridamol/uso terapéutico , Método Doble Ciego , Quimioterapia Combinada , Femenino , Oclusión de Injerto Vascular/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Fenprocumón/administración & dosificación , Fenprocumón/uso terapéutico , Estudios Prospectivos , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento , Grado de Desobstrucción Vascular/efectos de los fármacosRESUMEN
OBJECTIVES: This study was conducted to determine the efficacy and safety of long-term treatment with the orally active dopamine agonist ibopamine in patients with mild to moderate chronic congestive heart failure and to compare the results with those of treatment with digoxin and placebo. BACKGROUND: Ibopamine and digoxin are drugs that exert hemodynamic and neurohumoral effects. Because there is accumulating evidence that progression of disease in chronic heart failure is related not only to hemodynamic but also to neurohumoral factors, both drugs might be expected to have a favorable long-term effect. METHODS: We studied 161 patients with mild to moderate chronic heart failure (80% in New York Heart Association functional class II and 20% in class III), who were treated with ibopamine (n = 53), digoxin (n = 55) or placebo (n = 53) for 6 months. Background therapy consisted of furosemide (0 to 80 mg); all other drugs for heart failure were excluded. Clinical assessments were made at baseline and after 1, 3 and 6 months. RESULTS: Of the 161 patients, 128 (80%) completed the study. Compared with placebo, digoxin but not ibopamine significantly increased exercise time after 6 months (p = 0.008 by intention to treat analysis). Ibopamine was only effective in patients with relatively preserved left ventricular function, as it significantly increased exercise time in this subgroup (for patients with a left ventricular ejection fraction > 0.30; p = 0.018 vs. placebo). No patient receiving digoxin withdrew from the study because of progression of heart failure, compared with six patients receiving ibopamine and two receiving placebo. At 6 months, plasma norepinephrine was decreased with digoxin and ibopamine therapy (-106 and -13 pg/ml, respectively) but increased with placebo administration (+62 pg/ml) (both p < 0.05 vs. placebo). Plasma aldosterone was unaffected, but renin was decreased by both agents after 6 months (p < 0.05 vs. placebo). Total mortality and ambulatory arrhythmias were not significantly affected by the two drugs. CONCLUSIONS: Ibopamine and digoxin both inhibit neurohumoral activation in patients with mild to moderate chronic heart failure. However, the clinical effects of these drugs are different and appear to be related to the degree of left ventricular dysfunction.
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Cardiotónicos/uso terapéutico , Desoxiepinefrina/análogos & derivados , Digoxina/uso terapéutico , Dopaminérgicos/uso terapéutico , Insuficiencia Cardíaca/tratamiento farmacológico , Adolescente , Adulto , Anciano , Aldosterona/sangre , Desoxiepinefrina/uso terapéutico , Método Doble Ciego , Electrocardiografía Ambulatoria , Prueba de Esfuerzo , Femenino , Insuficiencia Cardíaca/sangre , Insuficiencia Cardíaca/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Países Bajos , Norepinefrina/sangre , Estudios Prospectivos , Renina/sangre , Índice de Severidad de la EnfermedadRESUMEN
To assess the optimal level of oral anticoagulation to prevent occlusion of vein coronary bypass grafts, 318 patients from a graft patency trial were analysed retrospectively. Oral anticoagulant therapy was started one day before surgery and continued for one year, after which graft occlusion was assessed by angiography. The aimed level of anticoagulation was 2.8-4.8 International Normalized Ratio (INR). Clinical outcome was assessed by the incidence of myocardial infarction, thrombosis and major bleeding. The observed anticoagulation level was 2.8-4.8 INR for 54%, and 1.8-3.8 INR for 75% of time per patient. Occlusion rates in patients who spent < 35, 35-70, and > or = 70% of time within INR range 2.8-4.8 were 10.5%, 10.8% and 11.8%, respectively (differences not statistically significant). Patients who spent > or = 70% of time within INR range 1.8-3.8 versus 2.8-4.8 showed comparable occlusion rates. The risk of graft occlusion was not related to quality of anticoagulation early (0-3 months) or late (3-12 months) after surgery. Myocardial infarction, thrombosis and major bleeding occurred in 1.3%, 2.0% and 2.9% of patients. To maintain vein graft patency in the first postoperative year by oral anticoagulation, a level within INR range 1.8-3.8 for > or = 70% of time seems to be sufficient.
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Anticoagulantes/uso terapéutico , Puente de Arteria Coronaria/efectos adversos , Oclusión de Injerto Vascular/prevención & control , Administración Oral , Relación Dosis-Respuesta a Droga , Estudios de Seguimiento , Humanos , Incidencia , Infarto del Miocardio/epidemiología , Infarto del Miocardio/etiología , Distribución Aleatoria , Estudios Retrospectivos , Resultado del Tratamiento , VenasRESUMEN
To assess the thrombotic risk of aprotinin in aortocoronary bypass surgery, we retrospectively analyzed the results of a trial, originally designed to compare the effects of one-year treatment with various antithrombotic drugs in the prevention of vein-graft occlusion. Graft patency at one year was assessed by angiography. Myocardial infarction, thromboembolism, major bleeding, and death were clinical endpoints. Of 948 randomized patients, 42 received aprotinin, all enrolled by one of the participating centres. Occlusion rates of distal anastomoses were 20.5% in the aprotinin group and 12.7% in the non-aprotinin group (p = 0.091). The proportions of patients with occluded grafts were 44.1% versus 26.3% (p = 0.029). Perioperative myocardial infarction occurred in 14.3% and 7.0%, respectively (p = 0.12). Mean postoperative blood loss was 451 ml in the aprotinin group compared with 1039 ml in the non-aprotinin group (p < 0.0001). Mean transfusion requirements were 1.1 U versus 2.1 U of red blood cells (p = 0.004). Aprotinin decreases blood loss and transfusion requirement. Our data suggest that this benefit may be associated with a reduction of graft patency and an increased risk of myocardial infarction.
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Aprotinina/efectos adversos , Puente de Arteria Coronaria/efectos adversos , Fibrinolíticos/efectos adversos , Oclusión de Injerto Vascular/inducido químicamente , Infarto del Miocardio/inducido químicamente , Humanos , Estudios Retrospectivos , Factores de Riesgo , Resultado del TratamientoRESUMEN
Absorption of felodipine is rapid and complete. A pronounced first-pass metabolism results in a bioavailability of 15%, irrespective of the oral formulation used. The peak plasma concentrations and area under the plasma concentration-time curve are linearly related to the dose. The variability in plasma concentrations is wide, and individualization of the dosage is recommended. Plasma felodipine concentrations are increased in the elderly, and in patients with congestive heart failure or liver cirrhosis; in these patients felodipine should be started at a low dosage. Food intake has no clinically significant effect on felodipine absorption. Serum digoxin concentrations are increased by felodipine in plain tablet form, but not when it is administered as extended release tablets. Activators, inducers and inhibitors of the cytochrome P450 system affect the plasma concentrations of felodipine. No displacement reactions with high affinity protein binding drugs have been observed. There is a significant correlation between plasma concentration and haemodynamic effect. The mean elimination half-life of 24h together with the extended release formulation of felodipine favours once-daily dosage in patients with hypertension.
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Felodipino/farmacocinética , Absorción Intestinal/fisiología , Disponibilidad Biológica , Relación Dosis-Respuesta a Droga , Interacciones Farmacológicas , Heces/química , Felodipino/sangre , Felodipino/uso terapéutico , Felodipino/orina , Humanos , Estructura Molecular , Valores de ReferenciaRESUMEN
The central hemodynamic effects of metoprolol in acute myocardial infarction have been studied in a multicenter, double-blind, randomized trial. One hundred and ninety patients with acute myocardial infarction not previously on beta blockers with heart rate greater than 65 beats/min and blood pressure greater than 105 mm Hg and without clinical signs of serious heart failure were included. After insertion of a pulmonary artery catheter, patients were randomized to metoprolol, 15 mg intravenously, and 50 mg 4 times a day orally (n = 95) or placebo (n = 95) with a mean delay of 7.2 hours. Hemodynamic measurements were made at baseline and repeatedly during 24 hours. Heart rate, systolic blood pressure and cardiac index were all immediately reduced by 10 to 20% in the metoprolol group and the difference compared with placebo was maintained throughout the 24 hours (p less than 0.001). Pulmonary capillary wedge pressure (PCWP) in the metoprolol group increased from 13.7 +/- 6.7 to a peak of 15.5 +/- 5.5 mm Hg 30 minutes after injection. The difference compared with placebo was maintained for 8 hours (p less than 0.01). This increase was seen only in the patient group with initial PCWP below the median of 13 mm Hg. In patients with initial PCWP above the median a continuous decrease was observed in both the placebo and metoprolol groups. Thus high initial PCWP was not associated with intolerance to metoprolol. Based on hemodynamic measurements tolerance to metoprolol was good.
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Hemodinámica/efectos de los fármacos , Metoprolol/uso terapéutico , Infarto del Miocardio/tratamiento farmacológico , Anciano , Ensayos Clínicos como Asunto , Quimioterapia Combinada , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/fisiopatología , Presión Esfenoidal Pulmonar , Distribución Aleatoria , Factores de TiempoRESUMEN
Acute hemodynamic and hormonal responses to ramipril in comparison with captopril were studied in 10 patients with moderate to severe congestive heart failure in an open, randomized study. Both drugs were given to 5 patients each in 2 increasing doses on 2 successive days. After 5 mg of ramipril angiotensin converting enzyme (ACE) activity was significantly decreased during 24 hours with a maximum decrease 4 hours after administration. Mean arterial blood pressure decreased from 84 +/- 5 to 62 +/- 5 mm Hg at 4 hours and 71 +/- 4 mm Hg at 12 hours, respectively, after this dose. Capillary wedge pressure decreased from 19 +/- 1 mm Hg to 13 +/- 1 mm Hg at 4 hours with a maximum increase in cardiac output from 3.8 +/- 0.3 liters/min to 4.4 +/- 0.3 liters/min at 2 hours. No significant cardiac effects were present 8 hours after administration. After 10 mg of ramipril, cardiac and hormonal effects showed a quicker onset of action and longer duration compared with the 5 mg dose. Mean arterial pressure decreased to 61 +/- 6 mm Hg. Similar effects were seen after captopril, but with a significantly shorter duration. Mean arterial pressure decreased from 82 +/- 4 mm Hg to 64 +/- 5 mm Hg after 12.5 mg and to 58 +/- 6 mm Hg after 25 mg of captopril. In patients with congestive heart failure ramipril has the hemodynamic profile of a long-acting and potent ACE inhibitor. Significant cardiac effects are present during 4 to 8 hours and ACE activity is still significantly inhibited 24 hours after a single dose of ramipril.(ABSTRACT TRUNCATED AT 250 WORDS)
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Inhibidores de la Enzima Convertidora de Angiotensina , Presión Sanguínea/efectos de los fármacos , Compuestos Bicíclicos con Puentes/uso terapéutico , Hidrocarburos Aromáticos con Puentes/uso terapéutico , Captopril/uso terapéutico , Insuficiencia Cardíaca/tratamiento farmacológico , Sistema Renina-Angiotensina/efectos de los fármacos , Anciano , Compuestos Bicíclicos con Puentes/efectos adversos , Enfermedad Crónica , Insuficiencia Cardíaca/metabolismo , Insuficiencia Cardíaca/fisiopatología , Humanos , Persona de Mediana Edad , Ramipril , Distribución AleatoriaRESUMEN
Intravenous streptokinase administration is now a widely applied therapy for patients in the early hours of acute myocardial infarction (AMI). The dosages used do not appear to be based on comparative clinical investigations. Therefore a double-blind randomized trial was carried out to establish the optimal dose of streptokinase. A total of 189 patients who had symptoms of AMI for less than 4 hours were treated with 200,000, 750,000, 1,500,000 or 3,000,000 IU streptokinase intravenously. At coronary angiography 2.8 +/- 2.7 hours (mean +/- standard deviation) after the start of streptokinase infusion, patency of the infarct-related coronary artery was observed in 38, 75, 60 and 82% of the patients, respectively, in the 4 groups. The result of the dosage of 200,000 IU was significantly poorer than that of the other dosages (p less than 0.01). The result of a dosage of 3,000,000 IU was significantly better than that of 1,500,000 IU (p less than 0.05), but the differences with 750,000 IU were not significant. Blood transfusion was required in 4 patients (2%), distributed over the 4 groups in 0, 2, 1 and 1 of the patients. One patient had major bleeding; this patient had been treated with 750,000 IU. The 3-month mortality-rate in the whole study population was 5%. Thus, of the 4 doses of streptokinase tested, 750,000 IU is the minimal therapeutic dosage, and the arguments for 1,500,000 IU as standard therapy for comparison with other fibrinolytic drugs are poor. The best results in this study were achieved with 3,000,000 IU, but further research will be needed to establish the efficacy and safety of this new regimen.
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Infarto del Miocardio/tratamiento farmacológico , Estreptoquinasa/administración & dosificación , Anciano , Angiografía , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Estudios de Seguimiento , Hematoma/inducido químicamente , Hemorragia/inducido químicamente , Humanos , Infusiones Intravenosas , Masculino , Persona de Mediana Edad , Estudios Multicéntricos como Asunto , Infarto del Miocardio/diagnóstico por imagen , Ensayos Clínicos Controlados Aleatorios como Asunto , Estreptoquinasa/efectos adversos , Estreptoquinasa/uso terapéutico , Factores de TiempoRESUMEN
Angiotensin-converting enzyme (ACE) inhibition is currently the cornerstone of congestive heart failure (CHF) therapy, but these drugs are not tolerated in up to 20% of patients. For these patients, therapeutic alternatives with comparable efficacy are needed. Felodipine, a vasoselective dihydropyridine calcium antagonist with a slow onset of action and a long plasma half-life, may be such an agent. Therefore, the efficacy and safety of felodipine were examined and compared with enalapril using a double-blind design. We studied 46 patients with a left ventricular ejection fraction < 0.40, peak oxygen consumption < 20 ml.min-1.kg-1, and symptoms of CHF despite therapy with diuretics and digoxin. After 16 weeks of therapy, there were no statistically significant differences in peak oxygen consumption (felodipine +1.6, enalapril +2.5 ml.min-1.kg-1) and exercise tolerance (felodipine +61 seconds, enalapril +64 seconds). Quality-of-life parameters were affected slightly better by felodipine than by enalapril. Plasma norepinephrine decreased by 143 pg.ml-1 with enalapril and by 12 pg.ml-1 with felodipine (p < 0.20 between groups). Both drugs were generally well tolerated. These data suggest that felodipine and enalapril have comparable effects on exercise parameters in patients with CHF. Neurohumoral activation was not observed with either drug.
Asunto(s)
Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Bloqueadores de los Canales de Calcio/uso terapéutico , Enalapril/uso terapéutico , Felodipino/uso terapéutico , Insuficiencia Cardíaca/tratamiento farmacológico , Vasodilatadores/uso terapéutico , Anciano , Aldosterona/sangre , Inhibidores de la Enzima Convertidora de Angiotensina/efectos adversos , Bloqueadores de los Canales de Calcio/efectos adversos , Bloqueadores de los Canales de Calcio/farmacología , Método Doble Ciego , Enalapril/efectos adversos , Tolerancia al Ejercicio/efectos de los fármacos , Felodipino/efectos adversos , Felodipino/farmacología , Femenino , Insuficiencia Cardíaca/sangre , Insuficiencia Cardíaca/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Norepinefrina/sangre , Consumo de Oxígeno/efectos de los fármacos , Calidad de Vida , Renina/sangre , Vasodilatadores/efectos adversos , Vasodilatadores/farmacologíaRESUMEN
Coronary artery disease is an increasingly common medical problem in the elderly, and relatively few studies investigating drug therapy focus on this population. To assess the efficacy and safety of the calcium channel blocker, felodipine, and isosorbide mononitrate (ISMN), as adjunct to optimal beta-blocker therapy in elderly patients, a placebo-controlled, double-blind study was conducted in 46 patients, aged between 65 and 80 years, with documented stress-induced angina pectoris and myocardial ischemia. With use of a latin-square design, with 3 periods of 4 weeks each, exercise testing was performed after each period. Felodipine, 5 mg once daily, significantly improved both time to ischemic threshold and pain threshold (p = 0.02 and p = 0.003, respectively, vs placebo), and tended to increase total exercise time (p = 0.06 vs placebo). In contrast, ISMN, 20 mg twice daily, did not significantly affect these parameters. Comparison of the 2 active treatment arms showed that, overall, felodipine was more effective than ISMN, with a statistically significant difference for time to ischemic threshold (p = 0.02). With regard to safety, felodipine was also better tolerated than ISMN, which led to more patients discontinuing study medication with ISMN (p < 0.05 between ISMN and felodipine). It is concluded that in elderly patients who are treated with optimal beta blockade, felodipine, but not ISMN, leads to an additional significant reduction in ischemic parameters during exercise.(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Antagonistas Adrenérgicos beta/uso terapéutico , Angina de Pecho/tratamiento farmacológico , Felodipino/uso terapéutico , Dinitrato de Isosorbide/análogos & derivados , Vasodilatadores/uso terapéutico , Anciano , Estudios Cruzados , Preparaciones de Acción Retardada , Método Doble Ciego , Quimioterapia Combinada , Prueba de Esfuerzo/efectos de los fármacos , Felodipino/efectos adversos , Femenino , Humanos , Dinitrato de Isosorbide/efectos adversos , Dinitrato de Isosorbide/uso terapéutico , Masculino , Isquemia Miocárdica/tratamiento farmacológico , Estudios Prospectivos , Resultado del Tratamiento , Vasodilatadores/efectos adversosRESUMEN
There is increasing evidence that clinical deterioration in manifest chronic heart failure is related to both hemodynamic and neurohumoral factors. Only few data are available, however, on the progression of disease in its early stages, when treatment has not yet been initiated. The aim of this study was therefore to examine the changes in clinical and neurohumoral variables that occur over 6 months in patients with clinically stable and untreated heart failure, and to evaluate the influence of drugs that may affect these variables. Accordingly, we studied 64 patients with heart failure who were in New York Heart Association functional class II (88%) and III (12%). They were randomized to double-blind treatment with the oral dopamine agonist ibopamine (100 mg 3 times daily; n = 22), digoxin (0.25 mg once daily; n = 22) or placebo (n = 20). Their age (mean +/- SD) was 60 +/- 8 years, and left ventricular ejection fraction (mean +/- SD) was 0.33 +/- 0.08. Of the 64 patients, 56 (88%) completed the 6-month study period (p = NS between groups). Exercise time decreased in patients treated with placebo after 6 months (median -62 seconds; p < 0.05 vs baseline), but it increased with ibopamine (+48 seconds), and digoxin (+17 seconds; both p < 0.05 vs placebo). Plasma norepinephrine increased in the placebo group after 6 months (median + 31 pg/ml, p < 0.05 vs baseline), but decreased in patients receiving active drug treatment (ibopamine: -24 pg/ml, digoxin: -98 pg/ml, both p < 0.05 vs placebo). Plasma renin and aldosterone levels were unchanged after 6 months in the placebo group, but digoxin therapy slightly reduced plasma renin concentration (-5 microU/ml; p < 0.05 vs placebo).(ABSTRACT TRUNCATED AT 250 WORDS)