RESUMEN
Corticosteroids were proposed for the treatment of sepsis as early as 1940. Several RCTs cast serious doubts on the usefulness of high dose corticosteroids and doubt still persists regarding the efficacy of replacement therapy. Adrenal insufficiency (non-responders to the 250 microg corticotropin test: increase in cortisol < 9 microg/dl) is present in about half of patients with septic shock and is associated with higher rates of refractory hypotension and mortality. Peripheral glucocorticoid resistance, which may even occur more frequently, can be easily assessed at bedside using skin tests. Cortisol antagonizes the migration of inflammatory cells, the synthesis or action of virtually all proinflammatory mediators, promotes virtually all anti-inflammatory components and enhances humoral immunity by means of transcriptional interference between its receptor and both AP-1 and NF-kappaB. Cortisol mediates cardiovascular tolerance to endotoxin and the maintenance of vascular sensitivity to catecholamines. Low doses (about 300 mg daily for 5 days or more) of hydrocortisone increase vasoconstrictor response to catecholamines in animals, in healthy volunteers challenged with LPS and in several RCTs. Hydrocortisone also increases arterial pressure and decreases the duration of shock. A meta-analysis of all available clinical controlled studies showed a reduction in 28 days, all-cause mortality with glucocorticoids (RR = 0.88, 95% CI: 0.78 - 1.00; p = 0.04). However, there was a significant heterogeneity across the trials (p = 0.006). On the other hand, analysis of studies where low doses of glucocorticoids were given for prolonged periods showed a 24% reduction in the risk of all-cause mortality at 28 days in treated patients (RR = 0.76, 95% CI: 0.64 - 0.90; p = 0.002) without heterogeneity across the trials (p = 0.28). In conclusion, in severe sepsis, high doses of corticosteroids should not be given. Septic shock should be treated with a replacement dose of hydrocortisone.
Asunto(s)
Glucocorticoides/uso terapéutico , Choque Séptico/tratamiento farmacológico , Vasoconstrictores/uso terapéutico , Apoptosis/efectos de los fármacos , Presión Sanguínea/efectos de los fármacos , Humanos , Sistema Hipotálamo-Hipofisario/fisiopatología , Óxido Nítrico/fisiología , Sistema Hipófiso-Suprarrenal/fisiopatología , Choque Séptico/mortalidad , Choque Séptico/fisiopatologíaRESUMEN
Since there is very little available systematic information on the psychological profile of patients with cardiac arrhythmia, a battery of 12 standardized personality inventories was administered to 102 patients ranging in age from 19 to 69 years. Thirty-eight patients with frequent ventricular premature beats (more than 30 per hour) without myocardial infarction were significantly more psychologically symptomatic than 34 age- and sex-matched general medical/surgical patients. The variables found to be significant portray the patient with frequent ventricular premature beats without myocardial infarction: high scores for hysteria, less moral orientation, more anxiety, depression and social alienation, and an inhibited and low respectful style. This combination of psychological variables produced a discriminant function (p less than 0.001) that accounted for 53 percent of the variance between the arrhythmia/no myocardial infarction group and the medical/surgical control group and could correctly predict group membership in 83.3 percent of cases. These results may have further implications in nonpharmacologic and psychotropic adjuncts to antiarrhythmic therapy.
Asunto(s)
Arritmias Cardíacas/psicología , Determinación de la Personalidad , Adulto , Anciano , Ansiedad , Arritmias Cardíacas/etiología , Depresión , Femenino , Humanos , Histeria , Inhibición Psicológica , Relaciones Interpersonales , Masculino , Persona de Mediana Edad , Infarto del Miocardio/complicaciones , Alienación SocialRESUMEN
This 68 year old man had recurrent episodes of paroxysmal atrial tachycardia, probably due to chronic pericarditis, persisting over a 7 year period. These episodes were resistant to all conventional medical therapy and at times produced ischemic chest pain. There was no evidence of Wolff-Parkinson-White syndrome either on the standard electrocardiogram or on the His bundle electrogram performed with atrial pacing. Rapid atrial pacing at a rate of 200/min was found to promptly terminate the tachycardia and restore normal sinus rhythm. Because of the refractoriness of the patient's tachycardia, in addition to the presence of ischemic chest pain during these episodes, a permanent radio frequency triggered atrial pacemaker was inserted which enables him to initiate rapid atrial pacing by pressing an external control. The patient has been maintained on antiarrhythmic medications in an attempt to decrease the frequency of these episodes; during an 8 month follow-up period, he has done well with approximately one episode of tachycardia each month requiring radio frequency atrial pacing for termination.
Asunto(s)
Fuentes de Energía Bioeléctrica , Marcapaso Artificial , Taquicardia Paroxística/terapia , Anciano , Electrocardiografía , Atrios Cardíacos , Humanos , Masculino , RecurrenciaRESUMEN
Sixty-eight (17 per cent) of 380 patients with acute myocardial infarction had the bradycardia-hypotension syndrome (ventricular rate below 60/min and systolic blood pressure less than 100 mm Hg) during the first 24 hours of admission to a large general hospital. In 61 of the 68 patients, the administration of atropine significantly increased the heart rate (from 46 plus or minus 14 to 79 plus or minus 12/min) (p less than 0.01) and systolic blood pressure (from 70 plus or minus 15 to 105 plus or minus 13 mm Hg) (p less than 0.001). In 26 of the 68 patients, ventricular premature complexes decreased from 9.4 plus or minus 3/min to 2.4 plus or minus 0.7/min (p less than 0.001) after the administration of atropine. It is concluded that the bradycardia-hypotension syndrome is not an uncommon complication following acute myocardial infarction and that selected doses of atropine may have a beneficial effect without significant complications.
Asunto(s)
Atropina/uso terapéutico , Bradicardia/etiología , Hipotensión/etiología , Infarto del Miocardio/complicaciones , Enfermedad Aguda , Adulto , Anciano , Atropina/farmacología , Bradicardia/diagnóstico , Bradicardia/tratamiento farmacológico , Femenino , Bloqueo Cardíaco/tratamiento farmacológico , Bloqueo Cardíaco/etiología , Humanos , Hipotensión/diagnóstico , Hipotensión/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Contracción Miocárdica/efectos de los fármacos , Infarto del Miocardio/mortalidad , Estudios Prospectivos , SíndromeRESUMEN
One hundred and nineteen episodes of accelerated ventricular rhythm (less than 125/min) were noted in 37 patinets with acute myocardial infarction during a 1 year period. The incidence was 12.7 per cent. Twenty-seven episodes of fast ventricular tachycardia (less than 125/min) were noted in 16 of these patients. Eighteen patients had anterior myocardial infarction and 19 inferior myocardial infarction. The mechanism of onset of accelerated ventricular rhythm was classified as escape in 65 episodes. Ventricular premature beats were noted close to episodes of accelerated ventricular rhythm in 31 patients and fast ventricular tachycardia in 14 patients. The morphology of accelerated ventricular rhythm was similar to the ventricular premature beats in 27 patients and similar to the fast ventricular tachycardia in 12. In 11 patinets the morphology of ventricular premature beats, accelerated ventricular rhythm and fast ventricular tachycardia were all the same. In six patients the coupling time of the ventricular premature beats and the onset of the accelerated ventricular rhythm were the same. In seven patients the morphology of the accelerated ventricular rhythm and fast ventricular tachycardia were the same, and the rate of the accelerated ventricular rhythm was exactly half that of the fast ventricular tachycardia. There were three deaths due to shock and heart failure. Three episodes of fast ventricular tachycardia progressed to ventricular fibrillation and were successfully cardioverted. It is concluded that accelerated ventricular rhythm and fast ventricular tachycardia were all the same. In six patients the coupling time of the ventricular premature beats and the onset of the accelerated ventricular rhythm were the same. In seven patients the morphology of the accelerated ventricular rhythm and fast ventricular tachycardia were the same, and the rate of the accelerated ventricular rhythm was exactly half that of the fast ventricular tachycardia. There were three deaths due to shock and heart failure. Three episodes of fast ventricular tachycardia progressed to ventricular fibrillation and were successfully cardioverted. It is concluded that accelerated ventricular rhythm is a relatively common complication of both anterior and inferior myocardial infarction. The high incidence of concomitant fast ventricular tachycardia, the frequency of ventricular premature beats with similar morphology and coupling time, and the instances of two arrhythmias having common rate multiples, suggest that at least in some instances accelerated ventricular rhythm may represent an ectopic focus with exit block.
Asunto(s)
Infarto del Miocardio/complicaciones , Taquicardia/complicaciones , Adulto , Anciano , Complejos Cardíacos Prematuros/etiología , Glicósidos Digitálicos/uso terapéutico , Femenino , Insuficiencia Cardíaca/complicaciones , Insuficiencia Cardíaca/tratamiento farmacológico , Ventrículos Cardíacos , Humanos , Lidocaína/uso terapéutico , Masculino , Persona de Mediana Edad , Monitoreo Fisiológico , Infarto del Miocardio/diagnóstico , Infarto del Miocardio/mortalidad , Taquicardia/diagnósticoRESUMEN
The effects of digoxin priming dose of 0.04 mg/kg body weight followed by infusion of 0.02 mg/kg per min) on local tension and length characteristics of the nonischemic, border and ischemic left ventricular zones were studied in 30 dogs using Walton-Brodie strain gauge arches and mercury-in-Silastic segment length gauges. Total tension in the nonischemic zone increased to 130.9 plus or minus 5.3 percent (P smaller than 0.001) of the control level in association with parallel changes in preejection and ejection tension and rate of rise of tension when infusion of digoxin was instituted 15 to 30 minutes after ligation. Consistent increases in tension variables were noticed when infusion of digitalis was initiated 45 to 60 minutes or 2 to 3 hours after ligation. Segment length remained unchanged. In the border zone, total tension decreased to 68.9 plus or minus 5.9 percent (P smaller than 0.01) after infusion of digitalis. When infusion of digitalis was instituted 45 to 60 minutes or 2 to 3 hours after occlusion, similar increases in total tension and other tension variables were seen. Segment length again showed no significant changes. There was an increase in total tension in 5 of the 12 ischemic zones studied when digitalis was infused 15 to 30 minutes after coronary arterial ligation, whereas a consistent (3 to 5 percent) decrease in tension was observed when infusion of digitalis was instituted 45 to 60 minutes and 2 to 3 hours after coronary occlusion. There was no increase in segment length. In summary, digitalis uniformly increased contraction of the nonischemic and border zones after coronary arterial ligation, but the effects on contraction and aneurysmal bulging in the ischemic zone were minimal.
Asunto(s)
Digoxina/uso terapéutico , Contracción Miocárdica/efectos de los fármacos , Infarto del Miocardio/fisiopatología , Animales , Vasos Coronarios/cirugía , Perros , Electrocardiografía , Ligadura , Infarto del Miocardio/tratamiento farmacológico , Factores de TiempoRESUMEN
Heart block was noted in 60 (35 complete and 25 second-degree) of 410 patients with acute inferior wall myocardial infarction. This group with heart block was compared to a control group of 30 patients with acute inferior wall infarction without heart block. The incidences of prior myocardial infarction and hypertension, in addition to the highest level of serum creatine phosphokinase and a maximum degree of ST-segment elevation in the inferior leads, were all greater in patients with heart block, as compared to the controls. The incidences of various complications, including dizziness and syncope, transient hypotension, cardiogenic shock, and congestive heart failure, were also higher in the group with heart block, while sinus nodal distrubances and atrial arrhythmias occurred with equal frequency. The mortality in those with heart block was 28 percent compared to 13 percent for the control. It is concluded that patients with heart block complicating acute inferior myocardial infarction have a greater amount of myocardial necrosis, a higher incidence of complications, and a higher mortality. Insertion of a temporary pacemaker should be considered when specific indications are present and not routinely.
Asunto(s)
Bloqueo Cardíaco/etiología , Infarto del Miocardio/complicaciones , Enfermedad Aguda , Bloqueo de Rama/etiología , Electrocardiografía , Femenino , Bloqueo Cardíaco/mortalidad , Bloqueo Cardíaco/terapia , Frecuencia Cardíaca , Humanos , Masculino , Persona de Mediana Edad , Marcapaso Artificial , Factores de TiempoRESUMEN
A patient with the sick sinus syndrome accompanying mirror-image dextrocardia which was associated with double superior venae cavae and an absent inferior vena cava is presented. A permanent transvenous demand pacemaker was inserted because of repeated episodes of dizziness and a documented 31/2-second period of asystole. Precise knowledge of the venous system and the location of the apex of the right ventricle was necessary prior to permanent pacemaker implantation.
Asunto(s)
Arritmia Sinusal/terapia , Dextrocardia/complicaciones , Marcapaso Artificial , Arritmia Sinusal/complicaciones , Arritmia Sinusal/diagnóstico , Dextrocardia/diagnóstico , Electrocardiografía , Femenino , Humanos , Persona de Mediana Edad , Situs Inversus/complicacionesRESUMEN
A total of 99 consecutive 24-hour Holter recordings with ventricular tachycardia were reviewed. Ventricular premature beats which occurred alone, and ventricular premature beats which initiated ventricular tachycardia were examined to determine which characteristics correlated with occurrence of ventricular tachycardia and which predicted rate and duration of ventricular tachycardia. The preceding R-R interval, the coupling interval, and a ratio of the two were examined. We found that ventricular tachycardia rate and duration increase with a shorter coupling interval, and the coupling interval/preceding R-R ratio was significantly different in single beats not initiating ventricular tachycardia. The ratio for the beat initiating ventricular tachycardia was smaller, indicating more prematurity.
Asunto(s)
Electrocardiografía , Taquicardia/diagnóstico , Anciano , Femenino , Frecuencia Cardíaca , Ventrículos Cardíacos , Humanos , MasculinoRESUMEN
The case presented had an electrocardiographic pattern of complete right bundle branch block with alternating periods of left anterior hemiblock and left posterior hemiblock. During one of the periods of alternating hemiblock, an His bundle electrogram was recorded and the His Purkinje (H-V interval) conduction time was within normal limits. In a second episode of alternating hemoblock, periods of Mobitz type II second-degree A-V block were noted. It is postulated that this case provides clinical evidence that incomplete block of a fascicle may occur in spite of an electrocardiographic pattern of complete fascicular block. It is thought that the periods of alternating hemiblock result from a changing relationship between conduction velocity and refractory period.
Asunto(s)
Bloqueo de Rama/diagnóstico , Anciano , Fascículo Atrioventricular , Electrocardiografía , Humanos , Masculino , Ramos SubendocárdicosRESUMEN
The auscultatory features typical of myxoma were absent in a patient with nonprolapsing left atrial myxoma. Angiocardiographic and echocardiographic findings including B-mode cross-sectional scanning are presented.