Fibrilación auricular (página 2)

OBJETIVO DEL ESTUDIO

Se diseña un estudio para 170 pacientes que acuden al Servicio de Urgencias de Cardiología del Hospital San Jacob .Hardbord. Connecticut, a los que se les administró aleatoriamente uno de los 5 tratamientos durante 1 año. La fase experimental del estudio comprendía 6 meses de tratamiento monitorizado y 1 año de tratamiento no monitorizado.

Al cabo de 6 meses se calculó el promedio mensual de cifras de Frecuencia cardiaca y al cabo de 1 año se evaluó en una escala subjetiva de 5 niveles el grado de eficacia del tratamiento en relación a las pautas de adherencia y de mantenimiento de Frecuencia Cardiaca en límites controlados (en rango de 60-110 cx´).

Se utilizó como técnica estadística la Prueba de la varianza de un factor, como extensión natural de la prueba de t-Student. La variable "Respuesta" es cuantitativa y, en este caso, la variable "Explicativa" es cualitativa de más de dos categorías. Básicamente se desea probar si hay diferencias estadísticamente significativas entre las medias de los grupos formados por la variable explicativa.

Las dispersiones de grupo fueron homogéneas y la variable "respuesta" fue normal en los grupos formados. Si no se cumpliera alguna de estas dos condiciones se comparan las Mediana de los grupos formados mediante la prueba no paramétrica de Kruskal-Wallis.

RESULTADOS

Se distribuyo aleatoriamente a los pacientes que cumplían criterios (Clínicos y Electrocardiográficos) de Fibrilación Atrial en 5 grupos homogéneos de 34 pacientes/grupo. Un grupo fue tratado con 0,250 mgrs diarios de Digoxina. El segundo grupo con Digoxina asociada a Amiodarona. El tercer grupo con Digoxina asociada a Flecaínida. El cuarto grupo con Digoxina asociada a Propafenona y el quinto grupo con Digoxina asociada a Diltiacen.

Se calcularon las tasas de eventos acumuladas según el método de Kapplanl-Meier.

Validación de Variables

Grupos A B C D E (Tratamientos)

Para el recuento de pacientes por tratamiento y la distribución de la Variable "Evolución":Frecuencias

Número de Casos: 170

EVALUACIÓN Frecuencias Porcentajes

Estadísticos descriptivos adecuados para la variable DFC en función de los diferentes Tratamientos:

Estadísticos para la variable DFC por TTO

Los tratamientos A,B,C, presentan una eficacia similar alrededor de 38 cx´ de disminución de Frecuencia Cardiaca.

El Tratamiento D es el más eficaz con una disminución de Frecuencia Cardiaca promedio de 51 cx´.

El Tratamiento E es el menos eficaz con una disminución de FC. De 32 cx´.

Disminución de FC en cx´ 1

Para saber si existen diferencias significativas entre el número medio de descenso en Frecuencia Cardiaca en cada tratamiento, utilizamos el Estadístico "Anova un Factor":

Dado que el valor p= 0.0007E se rechaza la HIPÓTESIS NULA.

Se concluye que las medias de DFC de los diferentes grupos de tratamiento NO SON IGUALES. Existiendo Diferencias Estadísticamente significativas entre los distintos tratamientos.

Para saber si es válido el modelo Anova estudiamos la homogeneidad de las varianzas de los diferentes grupos de Tratamiento y la normalidad de Residuos y Predicciones del modelo anterior. Para ello calculamos el Estadístico B de la "Prueba de Bartlett" como prueba de Elección..

Bartlett nos da un estadístico de B= 0.8128 que resulta NO significativo para un valor de p= 0.9367, concluyendo entonces que no hay diferencias entre las dispersiones de la respuesta a los diferentes tipos de Tratamientos y que los grupos son homocedásticos para esta variable.

Al existir homogeneidad de varianzas, no observándose patrones de comportamiento y existiendo simetría en los Residuos, se concluye que el "modelo Anova" está correctamente aplicado y es Válido.

De no resultar valido, utilizaríamos la "Prueba de Tukey" para contrastes múltiples entre los diferentes tratamientos.

Así se establece:

– Entre los tratamientos E, A, B y C no existen diferencias estadísticamente significativas.

– El Tratamiento D es, estadísticamente diferente y MÁS EFICAZ que todos los demás.

-El valor que aparece en +/- Limite de 0.9294 es la diferencia que deben tener dos tratamientos para ser estadísticamente diferentes.

– La significación de diferencia se establece a un nivel inferior a 0.05.

ANÁLISIS DE LOS TRATAMIENTOS EN RELACIÓN A LA VARIABLE "EVALUACIÓN

Los Tratamientos A, B y C presentan una Eficacia similar entre 1.88-2.17 puntos.

El Tratamiento D es el más eficaz con un promedio d 2.58 puntos.

El Tratamiento E es el menos eficaz con promedio de 1.58 puntos.

Dado que el valor p= 0.0184 se rechaza de nuevo HIPÓTESIS NULA. Así se concluye que " La Evaluación no es igual para los diferentes Tratamientos"

Utilizamos también la "Prueba de Kruskal-Wallis" para comparación de poblaciones con distribuciones no normales ni iguales entre si:

Diferencia Estadísticamente significativa para p= 0.0161 con Medianas de los Tratamientos no iguales.

La diferencia de Tratamiento D con rango medio de 106.2 frente a Tratamiento E con rango medio de 67.55 (106.2- 67.55 = 38.65) supera el valor crítico de 32.70, por lo que se han encontrado diferencias en relación a la variable Evaluación a un nivel de significación de 0.05. No se encuentran diferencias significativas entre Tratamientos A, B y C frente a E ni frente a D.

CONCLUSIONES.

Al desear saber si existen diferencias de eficacia entre 5 Tratamientos para la disminución de Frecuencia Cardiaca (DFC), la misma se establecerá por el promedio mensual durante 12 meses en rango de medición de: Inicio-6 meses-1 año, de disminución de dicha Frecuencia Cardiaca, así como por la valoración subjetiva y adhesión al Tratamiento propuesto por parte de los pacientes (170 pacientes). En el caso que los tratamientos dieran resultados diferentes se estableció qué tratamientos eran diferentes entre si.

El estudio se diseño sobre 170 pacientes afectos de Fibrilación Atrial No controlada (mayor de 100 cx´) y que cumplieran los Criterios de Inclusión. Se les administró, aleatoriamente, uno de los 5 tratamientos considerados.

A los 6 mese se calculó el promedio mensual de Disminución de Frecuencia Cardiaca ó la estabilización de la misma dentro de rango inferior a 100 cx´. Al año se evaluó, en escala subjetiva de 0-4 (5 niveles) el grado de eficacia del Tratamiento seguido en relación a las pautas de adherencia y de mantenimiento de Frecuencia Cardiaca en limites aceptables (Fibrilación Atrial Controlada).

A modo de Conclusiones finales, tras el Ensayo se puede afirmar:

No existen diferencias significativas entre los Tratamientos A, B y C presentando ellos una eficacia similar alrededor de 38 cx´ de disminución global.

El Tratamiento D, resultó ser el más eficaz con una disminución Promedio de 51 cx´.

El Tratamiento E resultó el menos Eficaz con una disminución de Frecuencia Cardíaca de 32 cx promedio.

Se rechaza Hipótesis Nula a un valor p= 0.0001.

Se concluye que existen diferencias estadísticamente significativas entre tratamientos.

DISCUSIÓN.

Todas las formas de tratamiento empleadas fueron eficaces en mayor o menor medida, reduciendo cifras de frecuencia cardiaca en ciclos por minuto.

La Terapia más efectiva fue la combinación de Digoxina con Diltiacen (Antagonista del calcio de la familia de las Benzodiacepinas).

La terapia menos efectiva fue la Digoxina aislada.

En el resto de Terapias no hubo diferencia significativa.

Proponemos, entonces, como Terapia de Elección en el control de una Fibrilación Atrial,- tanto paroxística, permanente ó persistente-, la combinación Digoxina-Diltiacen en pautas expuestas.

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ATRIAL FIBRILLATION

COMPARATIVE STUDY WITH FIVE GUIDELINES OF TREATMENT.

(CLINICAL TEST ON 170 PATIENT AFFECTION DE ACxFA)

Author:

Prof. Dr Francisco Ramon Breijo Márquez.

(Invitad professor)

Department of Clinical and Experimental Cardiology.

Sant Jacob's Hospital. Hardford. Connecticut

.

HYPOTHESIS

To compare the effects of fixed dose of Digoxina separately and in comparison with four antiarrhythmic drugs in doses fit for the control of Frequency Cardiac in patients with Atrial Fibrillation as well as to avoid the greater number of new episodes. The Null hypothesis would be that significant differences with these drugs in relation to isolated Digoxina do not exist.

SUMMARY

Well-known from the times of Hipócrates, the Atrial Fibrillation is, possibly, the more frequent Arrhythmia Cardiac after the Sinusal Tachycardyc. They have seted out different, – throughout the Times -, treatments as much for Control of the Frequency like of the Rate. Within these Treatments (Cardioversión Pharmacological) perhaps they are the Digitalics those that marked a time at the beginning of S.XIX.

Key words: Atrial Fibrilation. Cardioversión Farmacológica. Breijo. Anova. Kruskal-Wallis. Turkey.

BRIEF INTRODUCTION

Mechanism: These abnormal rates are originated in the auricle from ectópics centers. They are characterized being "irregularly irregular". (Chaotic Depolarisations atrials rights) The impulses are unloaded to frequencies that can be low or of up to 400 or more beats per minute. These frequencies do that the auricle depolarised very disorganizedly without appropriate contractions exist. This disorganization generates irregularities in the pattern of waves of the EKG. The waved deflections present/display varied forms and patterns. The base line of the layout adopts the form of small undulations from very fine to crude. Distinguishing characteristics: Frequency: Anyone, from slow to very fast the smaller frequencies of 100 greater frequencies of 100 are denominated "controlled". (Controlled Frequency) The denominate "uncontrolled" (Uncontrolled Frequency). Controlled frequencies are easy to identify, whereas the uncontrolled frequencies are more complicated. The auricular frequencies of 400 or cannot more be moderate. Waves: The P Waves are absent (due to the auricular activity chaotic). Interval PR: Given the absence of P waves, interval PR does not exist. Wide of the QRS: Normal limits of 0.10 seconds or less (although at intervals irregular). Leading factors: These patterns can appear in normal individuals and are usually transitory. Stress or alcohol in excess can cause them. If they do not revert spontaneously, the pharmacological agents are effective in these cases to return to a normal sinuses rate. The chronic auricular fibrillation (Persistent or Permanent) is related to a set of problems that include valvulopathy, coronary or hypertensive cardiopathy, miocardiopathy, Inflammation of the myocardium. Inflammation of the pericardium. Hypotiroidism, Cardiac insufficiency, pulmonary disease and can appear after a cardiac surgery. He is one of more common the abnormal heart rates. The temblors cardiac cameras not contracted appropriately and they fill of blood in the last part of diastole. The volume minute is reduced until in a 25%. The stagnation of blood in the camera increases the potential of formation of clots and consequently there are more possibilities of systemic tromboembolismo and ACV. The treatment must indicate carefully since the restoration of the normal function of the heart can cause the loosening of a clot and cause systemises embolisms.

Frequency: In the US: Prevalence is approximately 3% of the US adult population; incidence is 1 case per 1000 adults per year.

Mortality/Morbidity:

Much of the morbidity and some of the mortality resulting from AF are due to stroke. The risk of stroke is not due solely to AF; it increases substantially in the presence of other cardiovascular disease. The attributable risk of stroke from AF is estimated to be 1.5% for those aged 50-59 years, and it approaches 30% for those aged 80-89 years.

AF complicates acute myocardial infarction (AMI) in 5-10% of cases. The causes of AF in AMI are thought to be due to any number of factors, such as atrial infarction, atrial ischemic injury, atrial distension, or, perhaps, pericarditis. According to Rathore, et al, patients who developed new-onset AF during the course of myocardial infarction (MI) were at higher risk than patients who presented with chronic AF. Patients with AMI and AF tend to be older, be less healthy, and have poorer outcomes during hospitalization and after discharge than individuals without AF. AF is independently associated with an increased mortality rate.

Sex: Incidence is higher in men than in women.

Age:

• The incidence in persons aged 60-68 years is 1%.

• The incidence in persons older than 69 years is 5%.

MATERIAL and METHODS.

Design AND TARGET OF STUDY

DESIGN of the STUDY

With random allocation.

Monocéntric (Hospital of Sant Jacob.CON.)

Cases – controls.

Blind double.

Pilot to 12 months.

Patients Evaluated for possible inclusion: 765,

Patients including 170.

Pursuit 6 and 12 months.

Analysed Variables:

– Rules of 5 Treatments for control of Frequency in ACx FA not controlled FA.

– Decrease of Cardiac Frequency. (DFC).

– Subjective evaluation of the patient at the age of 6 and 12 months of beginning of Treatment.

– Number of new episodes in 6 months and 1 year.

– Efficacy of different Treatments.

DRUGS and USED TECHNIQUES

-Amiodarona + Digoxina. (Treatment A)

– Flecainída + Digoxina. (Treatment B)

– Propafenona + Digoxina. (Treatment C).

– Diltiacen + Digoxina. (Treatment D).

– Digoxina (Patient Control) 0.250 mgr/day during 12 months. (Treatment E).

CRITERIA OF INCLUSION

Age 75-year-old minor.

Revenue previous in Hospitable Unit for Control.

Characteristics Typical Electrocardiographic of

Atrial Fibrillation with Study Holter of 24 hours after the control of Frequency.

To be in Rank of 2-3 INR (Coagulation’s Preview).

CRITERIA OF EXCLUSION

Death in the Hospital.

Need of Cardiology Interventionist.

Complications added Electrocardiographic.

Pathology associated with danger of the life.

Absence in adhesion to the treatment or patients' bad availability.

Hypersensitivities known to some of the medicines.

TREATMENT GUIDELINES

* Hospitable Treatment:

– 250 cc of SSF with 0, 50 mgrs of Digoxin in Perfusion to 19 millilitre h. (Control).

– 250 cc SG with Guideline previous + 300 mgrs of Amiodarona to 19 ml/h.

– 250 cc SG with Digoxin + 150 mgrs of Flecainid to 19 ml/h.

– 250 cc of SG with Digoxina + 1 mgr kg of Propafenona to 19 ml/h.

– 250 cc SG with Digoxina + 15 mgrs/ hour of Diltiacen in perfusion

* Extra hospitable Treatment:

– Digoxin 0, 25 mgrs/day V.O.

– Digoxin 0, 25 mgrs + 300 mgrs of Amiodarone. V.O. / day.

– Digoxin 0, 25 mgrs + 100 mgrs of Flecainid V.O. / day.

– Digoxin 0, 25 mgrs + 300 mgrs of Propafenona V.O./day.

– Digoxin 0, 25 mgrs + 300 mgrs of Diltiacen V.O. / day.

OBJECTIVE OF THE STUDY

Is desired to establish if there are differences of effectiveness between five treatments for the control of the Frequency in the Paroxístyc Auricular Fibrillation. The effectiveness will settle down by the monthly average of Frequency Cardiac and new events of tachycardyc. As well as by the subjective valuation of effectiveness in the long, term. In case one demonstrates that the treatments are not equal, it is desired to establish what treatments are different between if.

The effectiveness of five treatments for the control of the Frequency in randomised cases of Atrial Fibrillation Paroxístic is compared. A study for 170 patients is designed who go to the Service of Urgencies of Cardiology of the San Jacob’s Hospital, Massachusetts. To that, one of the 5 treatments was administered to them randomly. The experimental phase of the study included/understood 6 months whit monitor treatment and 1 year of treatment no monitor. After 6 months the monthly average of numbers of Frequency calculated cardiac and after 1 year the degree of effectiveness of the treatment in relation to the adhesion guidelines was evaluated in a subjective scale of 5 levels and of maintenance of Frequency Cardiac in you limit controlled (in 60-110 rank cx´)

The Test of the variance of a factor was used like statistical technique, like natural extension of the test of t-Student. The variable "Answer" is quantitative and, in this case, "the Explanatory" variable is qualitative of more than two categories. It is desired to prove if there are statistically significant differences between the averages of the groups formed by the explanatory variable.

The group dispersions were homogenous and the variable "answer" was normal in the formed groups. If some of these two conditions were not fulfilled, they compare the Medium one of the groups formed by means of the nonparametric test of Kruskal-Wallis.

RESULTS

I distribute myself to the patients randomly who fulfilled criteria (Clinical and Electrocardiographic) of Fibrillation Atrial in 5 group’s whit 34 homogenous of patients. A group was dealt with 0.250 mgrs daily of Digoxina. The second group with associated Digoxina to Amiodarona. The third group with associated Digoxina to Flecaínida. The fourth group with associated Digoxina to Propafenona and the fifth group with associated Digoxina to Diltiacen. The rates of accumulated events calculated according to the method of Kapplanl-Meier.

Validation of Variables

Number of Cases: 170 Numerical Variable Valid Maximum Minimum Cod. Pac 170 170 1,0 170,0 TTO 170 0 — — 7,3 DFC 170 170 1,25 EVALUATION 170 170 0,0 4.0. Groups To B C D E (Treatments) N 34 34 34 34 34 Medium Average 3,7782 3,84 3,972 5,100 3,2500 4,2450 3,7150 3,82 5,4350 3.4100 For the count of patients by treatment and the distribution of the Variable "Evolution": Frequencies Number of Cases: 170 TTO Frequencies Percentage To 34 20,00 B 34 20,00 20,00 Cs 34 D 34 20,00 And 34 20.00 Total 170 100.00 EVALUATION Frequencies Percentage 4 26 15,29 3 40 23,53 1 38 22,35 0 22 12,94 2 44 25.88 Total 170 100.00. Statistical descriptive adapted for variable DFC based on the different Treatments: Statistical for variable DFC by TTO – Groups To B C D E N 34 34 34 34 34 Medium Average the 3,7782 3,8465 3,9721 5,1003 3,2500 4,2450 3,7150 3,8250 5,4350 3,4100 treatments To, b, c, presents/displays a similar effectiveness around 38 cx´ of diminution of Frequency Cardiac. Treatment D is the most effective with a diminution of Frequency Cardiac average of 51 cx´. The Treatment and is less effective with a diminution of FC. Of 32 cx´.

In order to know if significant differences between the average numbers of reduction in Frequency Cardiac in each treatment exist, we used the Statistical "Anova a Factor":

Anova A Factor

Variable Answer: Explanatory Variable DFC: TTO Number of Cases: 170 Extreme of Square Square G.L. Half F-value p-value Between 7,9507 Groups 62,7680 4 15,6920 0.0007E-2 Inside Groups 325,6535 165 1.9737 Total (corr.) 388.4215 169.

Since the value p = 0.0007E rejects the NULL HYPOTHESIS. One concludes that the averages of DFC of the different groups from treatment ARE NOT EQUAL.

Existing Statistically significant Differences between the different treatments. In order to know if it is valid the Anova model we studied the homogeneity of the variances of the different groups from Treatment and the normality of Remainders and Predictions of the previous model. For it we calculated statistical B of the "Test of Bartlett" like test of Election. Anova A Factor, Homocedasticidad Variable Answer: Explanatory Variable DFC: TTO Number of Cases: 170 Test C of Cochran: 0,2297 P-value = 1,0000 Test of Bartlett: 0,8128 P-value = 0,9367 Bartlett gives statistical of B = us 0,8128 that is no significant for a value from p = 0,9367, concluding then ones that are no differences between the dispersions of the answer to the different types from Treatments and that the groups are homocedásticos for this variable. When existing homogeneity of variances, not being observed behaviours patterns and existing symmetry in the Remainders, concludes that the "Anova model" correctly is applied and is Valid. Of not being court favourite, we would use the "Test of Tukey" for multiple resistances between the different treatments. Anova A Multiple Factor, Comparisons Variable Answer: Explanatory Variable DFC: TTO Number of Cases: 170 Method: Tukey HSD to the 95.00% Homogenous Groups Average TTO N And 34 3,2500 Xs To 34 3,7782 Xs B 34 3,8465 Xs C 34 3,9721 Xs D 34 5,1003 Xs Limit Resists Difference +/- To versus B -0,0682 0,9294 To versus C -0,1938 0,9294 To versus D * – 1,3221 * 0,9294 To versus and 0,5282 0,9294 B -0,1256 versus C 0,9294 B versus D * – 1,2538 * 0,9294 B versus and 0,5965 0,9294 Cs versus D * – 1,1282 * 0,9294 Cs versus and 0,7221 0,9294 D versus and * 1,8503 * 0.9294

*/statistically significant Difference.

Thus one settles down: – Between the treatments and, To, B and C statistically significant differences do not exist. – Treatment D is, statistically different and MORE EFFECTIVE than all the others. – The value that appears in +/- It limits of 0, 9294 is the difference that must have two treatments to be statistically different. – The difference meaning settles down at an inferior level to 0.05. Thus one settles down: – Between the treatments and, To, B and C statistically significant differences do not exist. – Treatment D is, statistically different and MORE EFFECTIVE than all the others. – The value that appears in +/- It limits of 0,9294 is the difference that must have two treatments to be statistically different. – The difference meaning settles down at an inferior level to 0.05.

ANALYSIS OF The TREATMENTS In relation to The VARIABLE "EVALUATION Statistical for the variable EVALUATION by TTO Groups To B C D E N 34 34 34 34 34 Medium Average the 2,0588 1,8824 2,1765 2,5882 1,5882 2,0000 2,0000 2,0000 3,0000 1,0000 Treatments To, B and C presents/displays a similar Effectiveness between 1.88-2.17 points. Treatment D is the most effective with an average d 2,58 points. The Treatment and is less effective with average of 1,58 points. Anova A Variable Factor Answer:

Explanatory Variable EVALUATION:

TTO Number of Cases: 170 Extreme of Square G.L. Half F-value p-value Between Groups 18,5882 4 4,6471 3,0570 0,0184 Inside Groups 250,8235 165 1.5201 Total (corr.) 269.4118 169 Since the value p = 0,0184 rejects NULL HYPOTHESIS again. Thus one concludes that "the Evaluation is not equal for the different Treatments" We also used the "Test of Kruskal-Wallis" for comparison of populations with no normal nor equal distributions between if:

Kruskal-Wallis Variable

Answer: Explanatory Variable EVALUATION: TTO Number of Cases: 170 Extreme groups n of Rm Ranks Average Rank To 34 2921,0000 85,9118 B 34 2651,0000 77,9706 89,8529 Cs 34 3055,0000 D 34 3611,0000 106,2059 And 34 2297,0000 67.5588 Statistical of Kruskal-Wallis (without correction by ties): 11.5990 Statistical of Kruskal-Wallis (with correction by ties): 12,1742 Degrees of freedom: 4 p-value: 0.0161.

Statistically significant difference for p = 0,0161 with Medium of the no equal Treatments. The difference of Treatment D with average rank of 106,2 as opposed to Treatment and with average rank of 67,55 (106,2- 67,55 = 38,65) surpasses the critical value of 32,70, reason why have been differences in relation to the variable Evaluation at a level of 0.05 meaning. Are not significant differences between Treatments To, B and C as opposed to and nor as opposed to D.

CONCLUSIONS.

When wishing to know if differences of effectiveness between 5 Treatments for the diminution of Frequency Cardiac exist (DFC), the same one will settle down by the monthly average during 12 months in rank of measurement of: Beginning

6 months-1 year, of diminution of this Frequency Cardiac, as well as by the subjective valuation and adhesion to the Treatment proposed on the part of the patients (170 patients). In the case that the treatments gave different results settled down what treatments were different between if. The study design on 170 patient affection of Atrial Fibrillation no controlled (greater of 100 cx´) and that fulfilled the Criteria of Inclusion. It was administered to them, randomly, one of the 5 considered treatments. To the 6 cx´ pulls calculated the monthly average of Diminution of Frequency Cardiac or the stabilization of the same one within inferior rank to 100. To the year it was evaluated, in subjective scale of the 0-4 (5 levels) degree of effectiveness of the Treatment followed in relation to the adhesion guidelines and of maintenance of Frequency Cardiac in you limit acceptable (Atrial Fibrillation Controlled). As final Conclusions, after the Test it is possible to be affirmed: Significant differences between Treatments A, B and C does not exist presenting/displaying them a similar effectiveness around 38 cx´ of global diminution. Treatment D turned out to be the most effective with a diminution Average of 51 cx´. The Treatment and was less Effective with a diminution of 32 Cardiac Frequency of cx average. Null Hypothesis to a value is ejected p = 0.0001. One concludes that statistically significant differences between treatments exist.

DISCUSSION.

All the used forms of treatment were effective in greater or smaller measurement, reducing numbers of frequency cardiac in cycles per minute. The most effective Therapy was the combination of Digoxin with Diltiacen (Antagonistic of calcium of the family of the Benzodiacepins). The less effective therapy was the isolated Digoxin. In the rest of Therapies there was no significant difference. We propose, then, like Therapy of Election in the control of a Atrial Fibrillation, – paroxístyc, permanent or persistent -, the Digoxin-Diltiacen combination in exposed guidelines.

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Autor:

Prof. Dr. Francisco Ramón Breijo Márquez.

(Profesor Invitado)

Departamento de Cardiología Clínica y Experimental.

Sant Jacob’s Hospital. Hardford. Connecticut

Correspondencia: .