Asunto(s)
Insuficiencia Cardíaca/diagnóstico , Trasplante de Corazón/fisiología , Hemodinámica/fisiología , Complicaciones Posoperatorias/diagnóstico , Prueba de Esfuerzo , Estudios de Seguimiento , Insuficiencia Cardíaca/epidemiología , Insuficiencia Cardíaca/fisiopatología , Frecuencia Cardíaca/fisiología , Humanos , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/fisiopatología , Intercambio Gaseoso Pulmonar/fisiología , Pruebas de Función Respiratoria , Factores de TiempoAsunto(s)
Angina Inestable/diagnóstico , Enfermedad Coronaria/diagnóstico , Infarto del Miocardio/diagnóstico , Adulto , Anciano , Angina Inestable/tratamiento farmacológico , Aspirina/administración & dosificación , Enfermedad Coronaria/tratamiento farmacológico , Electrocardiografía Ambulatoria , Prueba de Esfuerzo , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Nifedipino/administración & dosificación , Nitroglicerina/administración & dosificación , Estudios Prospectivos , Procesamiento de Señales Asistido por ComputadorRESUMEN
Questionnaires and a sub-maximal exercise test were used to assess occupational and leisure time physical activity as well as physical fitness in a standardized prospective study in 2,565 Belgian and Slovakian middle-aged healthy workers. Less than 5% of the subjects engaged in strenuous work requiring an energy expenditure above 31.5 kJ.min-1. One-third of the Belgians and 50% of the Slovakians reported no heavy leisure time activity during the preceding 12 months. Physical fitness, defined as the workload at heart rate 150 beats.min-1 (standardized for body weight), was significantly higher in Slovakians as compared to Belgians (1.52 +/- 0.28 W.kg-1 and 1.48 +/- 0.28 W.kg-1; P less than 0.001). Occupational physical activity in Belgians and heavy leisure time activity in Slovakians were independently related to fitness levels. However, each activity score explained less than 1% of the variance of physical fitness. We conclude that in these mainly sedentary, middle-aged subjects, fitness levels are independent from the usual physical activity patterns.
Asunto(s)
Actividades Recreativas , Esfuerzo Físico , Aptitud Física , Trabajo , Adulto , Bélgica , Presión Sanguínea , Checoslovaquia , Frecuencia Cardíaca , Humanos , Masculino , Persona de Mediana Edad , Triglicéridos/sangreRESUMEN
To investigate the mechanism of action of nitrovasodilators in exercise-induced angina, 15 patients with chronic stable angina underwent a symptom-limited supine exercise test (exercise 1). After recovery, in 10 patients (group I) a coronary vasodilator, SIN-1 (the active metabolite of molsidomine) was injected into the most diseased coronary artery (80 micrograms in 4 min). In the remaining 5, a placebo was injected (group II). Immediately thereafter, the same exercise (exercise 2, identical workloads and exercise duration) was repeated. In group I, after intracoronary injection of SIN-1, the control values at rest (including pulmonary wedge pressure) did not significantly change. Heart rate, blood pressure and cardiac index rose in a similar way during exercises 1 and 2 (61, 20, 26 and 62, 21, 35%, respectively). However, 3 patients were angina-free without ST-changes during exercise 2. In the remaining 7, the ST/heart rate slope was reduced (60%; p less than 0.02), the increase in pulmonary wedge pressure was less pronounced (p less than 0.01) and ST-depression at end-exercise 2 was smaller: 1.3 +/- 0.3 versus 2.1 +/- 0.3 mm (p less than 0.01) for identical work loads and double products. In group II, exercise 2 was identical to exercise 1 and the ST/heart rate slopes were quite reproducible. Therefore, these results argue for an improvement in coronary blood supply after intracoronary SIN-1 and suggest that the beneficial action of nitrovasodilators could be related to direct effects on the coronary circulation. However, the magnitude of this mechanism seems variable from one patient to another.
Asunto(s)
Angina de Pecho/tratamiento farmacológico , Molsidomina/análogos & derivados , Vasodilatadores/farmacología , Adulto , Anciano , Vasos Coronarios , Prueba de Esfuerzo , Hemodinámica/efectos de los fármacos , Humanos , Inyecciones Intraarteriales , Masculino , Persona de Mediana Edad , Molsidomina/administración & dosificación , Molsidomina/farmacología , Vasodilatadores/administración & dosificaciónRESUMEN
To compare the effects of two beta-blocking drugs: a nonselective (propranolol) and a cardioselective with modest intrinsic sympathomimetic activity (visacor), 24 patients with stable angina pectoris performed a control exercise (without medication) on a bicycle ergometer (increments of 30 W every 3 min), and thereafter were randomized to receive either propranolol (40 mg t.i.d.) or visacor (200 mg once daily) for a 48-hour double-blind trial. The 2 groups on control exercise were similar with regard to their exercise tolerance: 7.6 +/- 2.3 versus 7.1 +/- 1.4 min (NS) and the behavior of heart rate, systolic, diastolic blood pressure and double product, at rest and during exercise. They exercised on the 2nd day 2 h after the intake of propranolol or visacor. In the 12 patients randomized to propranolol, heart rate, systolic and diastolic pressures, double product were significantly reduced at rest, compared with control exercise: 67 +/- 8 versus 81 +/- 10 beats/min (p less than 0.01), 132 +/- 20 versus 146 +/- 21 mm Hg (p less than 0.02), 80 +/- 8 versus 88 +/- 10 mm Hg (p less than 0.02), 8,828 +/- 1,927 versus 11,863 +/- 2,138 mm Hg X min-1 (p less than 0.001), respectively. On the contrary, in the 12 patients randomized to visacor, these parameters at rest were less modified and only heart rate was significantly decreased: 71 +/- 9 versus 81 +/- 11 beats/min (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Antagonistas Adrenérgicos beta/uso terapéutico , Angina de Pecho/tratamiento farmacológico , Bencenoacetamidas , Esfuerzo Físico , Simpatomiméticos/uso terapéutico , Anciano , Ensayos Clínicos como Asunto , Método Doble Ciego , Humanos , Masculino , Persona de Mediana Edad , Propanolaminas/uso terapéutico , Propranolol/uso terapéutico , Distribución AleatoriaRESUMEN
To provide more insight into the role of alpha-adrenergic coronary tone in exercise-induced angina, 9 patients with chronic stable angina underwent after coronary angiography a symptom-limited supine exercise test on a cyclo-ergometer. After recovery, phentolamine was directly injected into the most diseased vessel (2 mg in 5 minutes), and immediately thereafter the same exercise (identical workloads and exercise duration) was repeated. During exercise 1, heart rate (HR), mean blood pressure and cardiac index increased 51% (p less than 0.001), 23% (p less than 0.01) and 33% (p less than 0.01), respectively, and pulmonary artery wedge pressure (PA wedge) increased from 9 +/- 1 to 26 +/- 2 mm Hg (p less than 0.001). After intracoronary injection of phentolamine, control values (including PA wedge) at rest did not change significantly. During exercise 2, HR, mean blood pressure and cardiac index increased in a similar way--50% (p less than 0.001), 25% (p less than 0.01) and 40% (p less than 0.01), respectively; however the increase in PA wedge was less (p less than 0.01). ST-segment depression at the end of exercise 2 was smaller for identical workloads and double products: 1.5 +/- 0.3 mm vs 2.5 +/- 0.3 mm (p less than 0.01). ST/HR slope in exercise 2 also decreased 51% (p less than 0.01). These results show a less severe ischemic response after intracoronary alpha blockade and argue for an improvement in coronary blood supply.
Asunto(s)
Angina de Pecho/etiología , Vasos Coronarios/efectos de los fármacos , Fentolamina , Esfuerzo Físico , Receptores Adrenérgicos alfa/fisiología , Antagonistas Adrenérgicos alfa , Adulto , Anciano , Angina de Pecho/fisiopatología , Presión Sanguínea , Gasto Cardíaco , Angiografía Coronaria , Circulación Coronaria , Vasos Coronarios/fisiopatología , Electrocardiografía , Prueba de Esfuerzo , Frecuencia Cardíaca , Humanos , Masculino , Persona de Mediana Edad , Receptores Adrenérgicos alfa/efectos de los fármacosRESUMEN
The effects of molsidomine were studied in seven patients with refractory congestive heart failure by means of two-dimensional echocardiography. Four milligrams of molsidomine or placebo was sublingually administered in a double-blind crossover manner. End-diastolic dimension, end-systolic dimension, and mean velocity of circumferential fiber shortening were measured just below the mitral valve before drug or placebo administration and 1 hour later. No significant changes were observed with placebo. Heart rate and mean arterial pressure were not significantly modified with Molsidomine (80 to 83 bpm and 100 to 97 mm Hg, respectively). The reduction in end-diastolic dimension (67 to 61 mm; 9%; P less than 0.01) was slightly greater than the decline in end-systolic dimension (59 to 54 mm; 8%; p less than 0.01). The mean velocity of circumferential fiber shortening increased from 0.4 to 0.5 sec-1 but did not achieve statistical significance. Thus sublingual administration of molsidomine in patients with chronic heart failure reduces end-diastolic more than end-systolic dimension without effect on blood pressure, suggesting a predominant action on cardiac preload.
Asunto(s)
Insuficiencia Cardíaca/tratamiento farmacológico , Contracción Miocárdica/efectos de los fármacos , Oxadiazoles/uso terapéutico , Sidnonas/uso terapéutico , Vasodilatadores/uso terapéutico , Ecocardiografía , Femenino , Insuficiencia Cardíaca/patología , Insuficiencia Cardíaca/fisiopatología , Ventrículos Cardíacos/efectos de los fármacos , Ventrículos Cardíacos/patología , Humanos , Masculino , Molsidomina , Sidnonas/farmacología , Vasodilatadores/farmacologíaRESUMEN
Forty-six patients with stable angina pectoris were randomized to receive either oral sustained-release nitroglycerin (SRNG, 6.5 mg) or placebo (P) 3 times a day for a 2-week double-blind trial. They were investigated for the frequency of anginal episodes, for sublingual nitroglycerin consumption and for exercise tolerance. There was a slight but significant decrease in the number of anginal episodes (6.4 +/- 1.5 episodes/week with P, 4.9 +/- 1.7 with SRNG, p less than 0.005) and sublingual nitroglycerin consumption (3.9 +/- 1 tablets/week with P, 2.7 +/- 1 with SRNG, p less than 0.005). The patients performed 3 upright multistage (increments of 30 W every 3 minutes) exercise tests on a bicycle ergometer before the start of the study and 1 hour after the intake of SRNG or P, at the end of each double-blind phase. Exercise capacity, expressed as exercise duration, increased from 8.9 +/- 3.8 minutes with P to 10.2 +/- 3.8 minutes with SRNG (14.6%; p less than 0.001). At symptom-limited exercise, ST depression was significantly reduced (p less than 0.05) during the SRNG phase. Thirty-four patients (74%) reached a higher peak heart rate (139 beats/min with P, 145 beats/min with SRNG; p less than 0.001) and 35 patients (76%) a higher rate-pressure product (+6%; p less than 0.001). These changes in exercise tolerance are relatively modest and at least 11 patients would have benefited from larger doses of nitrates.(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Angina de Pecho/tratamiento farmacológico , Nitroglicerina/administración & dosificación , Administración Oral , Adulto , Anciano , Angina de Pecho/diagnóstico , Ensayos Clínicos como Asunto , Preparaciones de Acción Retardada , Método Doble Ciego , Electrocardiografía , Femenino , Hemodinámica , Humanos , Masculino , Persona de Mediana Edad , Nitroglicerina/efectos adversosRESUMEN
The acute effects of an oral preparation of sulmazol, a recently synthesized cardiotonic agent, were assessed by means of a Swan-Ganz catheter in 10 patients who had advanced heart failure that persisted despite treatment with digitalis, diuretics and nitrates. All patients demonstrated a hemodynamic improvement. Pulmonary wedge pressure decreased significantly 1 h after administration from 26 +/- 2 to 16 +/- 3 mm Hg (mean +/- SEM; 32%; p less than 0.01) and this decrease remained significant at least 6 h after intake. The cardiac index increased from 1.8 +/- 0.1 to 2.4 +/- 0.1 1/min/m2 (33%; p less than 0.01) and remained significant up to 6 h later. Total systemic and pulmonary resistances were also significantly decreased (peak changes 28% and 46%, respectively) up to 6 h later. Heart rate and mean blood pressure were unaffected. Once the duration of action was assessed for each patient, a short-term oral therapy was initiated for 48 h. Hemodynamic measurements performed 24 h and 36 h following the commencement of this chronic therapy showed the sustained hemodynamic improvement. 7 patients were continued on sulmazol therapy for 3 weeks to 6 months. Side effects were nausea and vomiting (which were likely to be dose-related), worsening arrhythmias and a possible rebound phenomenon after withdrawal. Although orally administered sulmazol shows promise as a potentially useful agent in the treatment of advanced heart failure, the safety of this drug remains to be established.
Asunto(s)
Cardiotónicos/uso terapéutico , Insuficiencia Cardíaca/tratamiento farmacológico , Hemodinámica/efectos de los fármacos , Imidazoles/uso terapéutico , Adulto , Anciano , Cardiotónicos/administración & dosificación , Cardiotónicos/efectos adversos , Ensayos Clínicos como Asunto , Femenino , Humanos , Imidazoles/administración & dosificación , Imidazoles/efectos adversos , Masculino , Persona de Mediana Edad , Factores de TiempoRESUMEN
Ten men with documented coronary artery disease and stable exertional angina underwent a double-blind crossover study to examine the benefit and the duration of action on their symptom-limited exercise capacity of 2 doses (2.5 and 6.5 mg) of sustained-release nitroglycerin (SRNG). A multistage bicycle test was performed in the sitting position by steps of 30 W each 3 minutes until the onset of typical angina pectoris. It was performed 24 hours before the start of the study; 1 and 5 hours after administration of placebo, and repeated after 2.5 and 6.5 mg of SRNG administered in a double-blind crossover study according to a 4 successive days protocol. No differences appeared between administration of placebo (1 and 5 hours) and the results obtained at the first exercise test. The dose of 2.5 mg of SRNG was effective on the symptom-limited working capacity but only at 1 hour (+9%; p less than 0.01). The dose of 6.5 mg was more effective both at 1 hour (+25%; p less than 0.001) and at 5 hours (+27%; p less than 0.001). All patients had angina at a higher heart rate (+5 to 8%; p = NS [not significant] and p less than 0.01), whereas systolic blood pressure and double product tended to be slightly but insignificantly increased. S-T depression at the onset of angina was insignificantly changed with placebo, and 2.5 and 6.5 mg of SRNG. It is concluded that 6.5 mg of orally administered SRNG is effective during at least 5 hours, and that the magnitude of the benefit and its duration are dose-related.