Usefulness of cardiac resynchronisation therapy devices and implantable cardioverter defibrillators in the treatment of heart failure due to severe systolic dysfunction: systematic review of clinical trials and network meta-analysis.

AIM: To assess the effectiveness of cardiac resynchronisation therapy (CRT), implantable cardioverter defibrillator (ICD) therapy, and the combination of these devices (CRT+ICD) in adult patients with left ventricular dysfunction and symptomatic heart failure. METHODS: A comprehensive systematic review of randomised clinical trials was conducted. Several electronic databases (PubMed, Embase, Ovid, Cochrane, ClinicalTrials.gov) were reviewed. The mortality rates between treatments were compared. A network was established comparing the various options, and direct, indirect and mixed comparisons were made using multivariate meta-regression. The degree of clinical and statistical homogeneity was assessed. RESULTS: 43 trials involving 13 017 patients were reviewed. Resynchronisation therapy, defibrillators, and combined devices (CRT+ICD) are clearly beneficial compared to optimal medical treatment, showing clear benefit in all of these cases. In a theoretical order of efficiency, the first option is combined therapy (CRT+ICD), the second is CRT, and the third is defibrillator implantation (ICD). Given the observational nature of these comparisons, and the importance of the overlapping CIs, we cannot state that the combined option (CRT+ICD) offers superior survival benefit compared to the other two options. CONCLUSIONS: The combined option of CRT+ICD seems to be better than the option of CRT alone, although no clear improvement in survival was found for the combined option. It would be advisable to perform a direct comparative study of these two options.

Cuantificación de la relación entre el gradiente transmitral y la duración de los ciclos cardíacos en pacientes con estenosis mitral y fibrilación auricular utilizando la técnica doppler / Quantification of the relationship between transmital gradient and cardiac cycle lenght in patients with mitral stenosis and atrial fibrillation using the doppler technique

Fundamento. En pacientes con estenosis mitral (EM) y fibrilación auricular (FA) se analiza y cuantifica la influencia del ciclo cardíaco (RR) sobre los gradientes transmitrales. Métodos. En 58 pacientes con EM pura y FA se obtienen mediante ecocardiografía-Doppler los gradientes transmitrales telediastólico (GTD) y medio (GM) y se relacionan con los intervalos RR, agrupando a los pacientes según el área valvular mitral: A=EM grave (área1,5 cm2).Resultados. La relación entre el GTD y los intervalos RR ha sido significativa e inversa en todos los casos.Considerando globalmente a todos los pacientes de cada grupo las rectas de regresión obtenidas han sido las siguientes: grupo A) GTD=27,3-0,021RR; n=608; p<0,0001; grupo B) GTD=16,8-0,013RR; n=878; p<0,0001; grupo C) GTD=11,2-0,009RR; n=472; p<0,0001. El mismo tipo de relación se ha observado al considerar la relación entre los GM y los intervalos RR. Conclusiones. En los pacientes con EM y FA existe una relación significativa e inversa entre los gradientes transmitrales y la duración de los ciclos cardíacos. La estimación de los gradientes transmitrales según la duración de los ciclos utilizando las funciones propuestas permite cuantificar las repercusiones hemodinámicas del control inadecuado de la frecuencia cardíaca en este tipo de pacientes (AU)

Dispersión del intervalo QT y variabilidad de la frecuencia cardíaca postinfarto. evolución temporal y relaciones con la función ventricular izquierda / QT interval dispersion and heart rate variability following myicardial infarction. Time course and relations with the left ventricular function

Introducción y objetivos. Se investigaron los cambios precoces en la dispersión del intervalo QT y variabilidad de la frecuencia cardíaca en un grupo de pacientes consecutivos hospitalizados por infarto de miocardio de cara anterior, así como el curso evolutivo de estos indicadores pronósticos durante un período de 6 meses y la relación entre estas variables y los parámetros de función ventricular izquierda. Métodos. Se estudiaron 42 pacientes consecutivos ingresados por infarto de miocardio de cara anterior con onda Q. Se llevaron a cabo en la primera semana y a los 6 meses postinfarto un análisis de la variabilidad de la frecuencia cardíaca (Holter de 24 horas) empleando el método de la demodulación compleja, una medida de la dispersión del intervalo QT en el electrocardiograma (ECG) estándar de 12 derivaciones (QT máximo - QT mínimo) y se obtuvieron los parámetros de función ventricular izquierda a partir de la ventriculografía de contraste y la extensión de la disfunción regional ventricular izquierda. Resultados. La dispersión del QT disminuyó significativamente entre la primera semana (0,07s [0,050,08]) y los 6 meses (0,06s [0,04-0,08], p =0,029); la extensión de la anormalidad de la motilidad parietal mostró una tendencia similar (desde 51 por ciento [27-56] hasta 33 por ciento [11-46], p<0,00001). En cambio, la desviación estándar de los ciclos RR aumenta entre la 1ª semana (31 ms [22-44]) y los 6 meses (43 ms [32-58], p< 0,00001). Sin embargo, la fracción de eyección ventricular izquierda, volumen telediastólico, y volumen telesistólico (46 ml/m2 [31-67] no mostraron cambios significativos en este período de tiempo. En la 1ª semana, la desviación estándar (r = 0,46, p< 0,01) y el ciclo RR medio (r = 0,59, p < 0,0001) se relacionaron con la fracción de eyección, Sin embargo, la dispersión de QT no se correlacionó con la variabilidad de la frecuencia cardíaca o los parámetros de función ventricular en la primera semana o a los 6 meses de evolución. No existieron diferencias en los parámetros autonómicos o hemodinámicos entre los pacientes que presentaron unos valores de dispersión del QT < 0,08 (n=15) o 0,08 ( n=16) segundos. Conclusiones. a) La dispersión del QT disminuye y la variabilidad de la frecuencia cardíaca aumenta en los primeros meses postinfarto; b) la disminución de la variabilidad de la frecuencia cardíaca tiende a ser mayor cuanto mayor es el deterioro de la función ventricular secundario al infarto; y c) no se han encontrado relaciones entre la dispersión del QT y las características clínicas, variabilidad de la frecuencia cardíaca o parámetros de función ventricular izquierda en la primera semana o a los 6 meses postinfarto (AU)

[The effect of the duration of the cardiac cycles on determining mitral valve area by means of pressure half-time]. / Influencia de la duración de los ciclos cardíacos en la determinación del área valvular mitral mediante el tiempo de hemipresión.

INTRODUCTION AND AIMS: To analyze the influence of variations in the length of cardiac cycle length of calculating mitral valve area by means of the pressure half time in patients with mitral valve stenosis and atrial fibrillation. METHODS: Fifty-nine patients with pure mitral valve stenosis and atrial fibrillation were subjected to transmitral flow measurements by continuous Doppler monitoring from the apical window. In each patient the pressure half time was quantified, corresponding to a minimum of 30 consecutive cycles. RESULTS: Considering all the measurements made in each patient, the correlation between pressure half time and cardiac cycle was significant in 20 cases (34%). The pressure half time variation coefficients were significantly greater when including the values corresponding to the shortest cycles. Thus, for cycle duration of > or = 800, 700, 600, 500 and 400 ms, the mean values were 0.096 +/- 0.041, 0.106 +/- 0.042 (NS), 0.128 +/- 0.032 (p < 0.05), 0.167 +/- 0.048 (p < 0.001) and 0.231 +/- 0.057 (p < 0.0001), respectively. Upon analyzing the relation between pressure half time and cardiac cycle with progressive exclusion of the longer cycles > or = 800, 700 and 600 ms the number of patients with significant correlation coefficients increased to 19/37 (51%), 12/23 (52%) and 4/6 (67%) on respectively excluding. CONCLUSIONS: Patients with mitral valve stenosis and atrial fibrillation show a variation in pressure half time that may complicate calculation of the mitral valve area. Variability is inherent to the measurement method, and is furthermore dependent upon cardiac cycle duration. This may be resolved by limiting determinations to cycles longer than 800 ms.

[Cardiac cysts. A case of isolated cardiac hydatidosis]. / Quistes cardíacos. Un caso de hidatidosis cardíaca aislada.

In the presence of cardiac cysts we must discard a hydatid disease, even if there is no involvement of other organs. Imaging techniques are useful for guiding the initial diagnosis. The presence of daughter vesicles or multiple cysts is very characteristic. We present a patient affected by cardiac hydatid disease, in the form of multiple cardiac cysts, without extracardiac affectation, who presented pericardial chest pain. The patient was dealt with surgery to avoid the risks of a cyst rupture.

Reduction of atrial fibrillation inducibility by radiofrequency ablation: an experimental study.

UNLABELLED: A study is made of the antifibrillatory effects of radiofrequency (RF)-induced atrial lesions using nine Langendorff-perfused rabbit hearts in which the atrial electrophysiological properties and atrial fibrillation (AF) inducibility were modified by atrial stretching. Using a multiple electrode consisting of 121 unipolar electrodes, determinations were made of the atrial refractory periods, conduction velocity, wavelength of the atrial activation process, and the inducibility of sustained AF episodes (duration over 30 s) by atrial burst pacing in four situations: (a) control; (b) following dilatation of the right atrium; (c) after adding an RF linear lesion at the cava-tricuspid annulus isthmus; and (d) after adding two RF linear lesions rounding the base of the right atrial appendage and extending from the inferior zone of the sulcus terminalis to the anterior wall of the appendage. Under control conditions, AF was not induced in any of the experiments. The wavelengths were 10.5 +/- 1.2 cm for basic cycles of 250 ms and 6.6 +/- 0.5 cm for cycles of 100 ms. Following dilatation, a significant decrease was recorded in the atrial refractory periods, conduction velocity, and wavelength, which reached values of 6.1 +/- 0.7 cm (250-ms cycle, P < 0.01), and 3.9 +/- 0.3 cm (100-ms cycle, P < 0.01); AF was induced in five cases (P < 0.05). After producing the lesion at the cava-tricuspid isthmus, the electrophysiological modifications induced by atrial dilatation persisted (wavelength = 6.2 +/- 0.6 cm (250-ms cycle) and 4.3 +/- 0.3 cm (100-ms cycle); P < 0.01 vs the control) and AF was triggered in eight cases (P < 0.0001). In turn, on adding the two lesions at the right atrial free wall and appendage, AF was induced only in one experiment (P = NS vs control), and the dilatation-induced decrease in refractoriness and wavelength was attenuated. Nevertheless, differences remained significant with respect to the controls, with the exception of the functional refractory periods determined at cycles of 100 ms. In this phase, the wavelength was 6.6 +/- 0.7 cm (250-ms cycle, P < 0.01 vs control) and 4.9 +/- 0.5 cm (100-ms cycle; P < 0.05). Atrial conduction between the zones separated by the lesions was blocked at any frequency, or selectively at rapid atrial activation frequencies. IN CONCLUSION: (a) the production of three linear lesions in the right atrium (cava-tricuspid isthmus, atrial appendage, and inferior free wall) reduces AF inducibility in the experimental model used; (b) conduction block (either absolute or frequency dependent) through the lesions, reduction in tissue mass caused by lesion creation, and possibly the attenuation of the shortening of atrial refractoriness and wavelength in the zones not separated by the lesions are implicated in the reduction of AF inducibility; and (c) the single lesion in the cava-tricuspid isthmus does not impede AF inducibility.

[The single coronary artery arising from the sinus of Valsalva. A rare cause of myocardial ischemia]. / Arteria coronaria única desde seno de Valsalva derecho. Una causa poco frecuente de isquemia miocárdica.

The presence of a congenital anomaly in coronary arteries can be the cause of a defective coronary flow and ischaemic symptoms. Although they are rare, we must suspect them in the presence of major cardiac events in young people. A single coronary artery is present if the entire coronary system arises from a solitary ostium. Its presence is regarded as having little clinical significance and it is usually a fortuitous finding on coronary angiography. We report the case of a patient with effort anginal symptoms, with a single coronary artery arising from the right sinus of Valsalva without obstructive atherosclerotic lesions.

[Evolution of the filling pattern of the left ventricle during the first year after an acute myocardial infarct. The influence of the infarct size]. / Evolución del patrón de llenado del ventrículo izquierdo durante el primer año tras un infarto agudo de miocardio. Influencia del tamaño del infarto.

OBJECTIVES: Acute myocardial infarction induces diastolic dysfunction as a result of the alteration of left ventricular relaxation and stiffness caused by ischemia and fibrosis. This study analyzes the association of infarct size with the diastolic filling pattern and the evolution of the latter during the first postinfarction year. PATIENTS AND METHODS: The study group consisted of 68 patients with a first acute myocardial infarction treated with thrombolytic agents. A Doppler echocardiography was performed at 8 +/- 2, 32 +/- 7 and 370 +/- 23 days after infarction. Five measurements of the ratio between E and A waves peak velocities (E/A ratio) and of the E deceleration time (EDT, ms) were averaged in each echocardiographic study. The patients were divided according to infarct size into a large infarct group (creatine kinase > 1,000 U/ml; 1,913 +/- 883; n = 26) and a small infarct group (creatine kinase < 1,000 U/ml; 556 +/- 227; n = 42). RESULTS: The large infarct group exhibited a greater E/A ratio and shorter EDT than the small infarct group in the first week (E/A ratio: 1.4 +/- 0.7 vs 0.8 +/- 0.3; p = 0.0001; EDT: 159 +/- 49 vs 192 +/- 56; p = 0.02) and at one month (E/A ratio: 1.2 +/- 0.7 vs 0.9 +/- 0.3; p = 0.01; EDT: 170 +/- 55 vs 207 +/- 40; p = 0.004); however no differences were observed between either group at one year in either E/A ratio (0.8 +/- 0.2 vs 0.9 +/- 0.4; NS) or EDT (207 +/- 44 vs 219 +/- 54; NS). In the large infarct group, E/A ratio decreased and EDT increased at one year compared to the first week (E/A ratio: p = 0.0004; EDT: p = 0.0001) and the first month (E/A: p = 0.02; EDT: p = 0.003); in contrast, in the small infarct group there were no significant differences in E/A ratio nor EDT during the first year postinfarction. CONCLUSIONS: In the first month postinfarction, large infarcts exhibit a greater E/A ratio and shorter EDT than small infarcts. The evolution of large infarcts is characterized by an attenuation of this pattern, with a progressive reduction of E/A ratio and prolongation of EDT during the first year post-infarction.

[E wave deceleration time predicts left ventricular telediastolic pressure in acute myocardial infarction in patients with systolic dysfunction]. / El tiempo de deceleración de la onda E predice la presión telediastólica del ventrículo izquierdo tras un infarto agudo de miocardio en pacientes con disfunción sistólica.

OBJECTIVES: Left ventricular end-diastolic pressure (LVEDP) is a useful parameter for the management of postinfarction patients. As the current methods of estimating LVEDP are invasive, the existence of non-invasive methods would be of great practical value. This study investigates the relation between LVEDP and Doppler parameters such as E wave deceleration time (EDT) and E/A ratio, at one month following an acute myocardial infarction. METHODS: Eighty-nine patients with a first acute myocardial infarction treated with thrombolytic agents were studied. Doppler-echocardiography at 29 +/- 3 days and cardiac catheterization at 30 +/- 4 days postinfarction were performed. According to the ejection fraction (EF), the patients were divided into group 1 (n = 17) with EF < 45%, and group 2 (n = 72) with EF > 45%. RESULTS: Overall, the E/A ratio showed a weak correlation with LVEDP (r = 0.32; p = 0.007), and EDT did not correlate with LVEDP. When patients from group 2 were analyzed, no correlation was found between LVEDP and either E/A or EDT. However, in patients from group 1, LVEDP strongly correlated with both EDT (r = -0.83; p = 0.00001) and E/A (r = 0.70; p = 0.003). Moreover, the sensitivity and specificity of an EDT of less than 150 ms in predicting a LVEDP > 20 mmHg was 100%. CONCLUSIONS: We conclude that at the first month after a myocardial infarction EDT provides a non-invasive and useful parameter for estimating LVEDP in patients with systolic dysfunction.

[Extrinsic compression of the pulmonary artery by non-microcytic lung carcinoma]. / Compresión extrínseca de la arteria pulmonar por un carcinoma no microcítico de pulmón.

A patient with a remitting non-microcytic pulmonary carcinoma was subjected to Doppler-echocardiography. The detection of a pericardial effusion with compression of the pulmonary artery due to an extrinsic mass indicated that the disease was progressing. The Doppler technique was used to evaluate the degree of arterial stenosis by determining the pressure gradient caused by it (49 mmHg) and to calculate the right ventricle pressure (75 mmHg). Tumor infiltration of mediastinal structures was posteriorly confirmed by computed tomography.

[I. Usefulness of the exertion test and other methods based on the electrocardiogram in chronic ischemic disease]. / I. Utilidad de la prueba de esfuerzo y de otros metodos basados en el electrocardiograma en la cardiopatía isquémica crónica.

Exercise testing still plays an important role in the management of patients with chronic ischemic heart disease, not only in the diagnosis but also in their prognostic and functional evaluation, and in the assessment of effects of the therapy. Moreover, ambulatory electrocardiography, signal averaged electrocardiography and heart rate variability provide useful information for certain groups of patients. This paper reviews the rationale, methodology and indications of the above mentioned procedures applied to chronic ischemic heart disease, with special reference to exercise testing. Recommendations for their use in clinical practice are also made.

[The automatic, beat-to-beat determination of the QT interval and analysis of its spontaneous variability under basal conditions]. / Determinación automática, latido a latido, del intervalo QT y análisis de su variabilidad espontánea en condiciones basales.

OBJECTIVES: An analysis is made of the automatic beat-by-beat measurement of QT and other intervals related to ventricular repolarization. The variability pattern of these intervals is investigated in normal subjects at rest, along with their relation to RR cycle variability. MATERIAL AND METHODS: The electrocardiographic signals (LII) from 11 normal subjects (mean age 31 +/- 10 years) were recorded over 5 min and processed by applying specific algorithms to determine beat-by-beat the RR, QT, RT, QTm and RTm intervals (Tm = peak of T wave). An analysis was made of the variability of these intervals in the time (standard deviation, variation coefficient, difference between maximum and minimum values) and frequency domains (spectral analysis applying the Fourier transform). RESULTS: The differences between the automatic measurements and those performed by two observers (n = 110) were respectively -1.3 +/- 6.4 and -3.7 +/- 6.5 ms for QT, - 1.0 +/- 1.4 and -1.0 +/- 2.3 ms for QTm, -0.3 +/- 1.4 and -0.2 +/- 1.8 ms for RTm, and 0.7 +/- 6.5 and -2.8 +/- 10.3 ms for RT. The QT and RT intervals exhibited greater variability (SD = 6 +/- 1 ms) than QTm and RTm (SD = 3 +/- 1 ms, p < 0.0001). These differences persisted on comparing the corresponding variation coefficients. The differences between the maximum and minimum measurements were 45 +/- 24 ms for QT and RT, the values being significantly less in the case of QTm (21 +/- 26 ms, p < 0.05) and RTm (20 +/- 27 ms, p < 0.05). In the frequency domain, the high- (HF) and low-frequency (LF) band energies were low in the series formed by the ventricular repolarization intervals, and the LF band normalized amplitude was significantly lower than in the RR series. There were no significant differences in the frequencies of the maximum values of the LF and HF bands of the RR series with respect to the QT series. The correlations between the RR intervals and the subsequent repolarization intervals obtained in each subject were not significant in 7 of the 11 subjects studied. CONCLUSIONS: The automatic beat-by-beat determination of the ventricular repolarization intervals is precise, particularly when considering the intervals defined by the T wave peak. Repolarization variability during the sinus rhythm at rest is small, and is not linearly related to modifications of the previous RR interval. Neurovegetative and humoral influences are postulated to explain QT variations. The neurovegetative and humoral influences that regulate cardiac cycle and ventricular repolarization variability at rest, are found to be quantitatively different.

[An analysis of heart rate variability. Spectrum analysis methods and complex signal demodulation]. / Análisis de la variabilidad de la frecuencia cardíaca. Métodos espectrales y demodulación compleja de la señal.

The analysis of heart rate variability provides valuable information in the noninvasive study of neurovegetative activity and its modifications induced by drugs, physiological maneuvers or disease processes, and in the evaluation of prognosis and risk stratification in different cardiovascular diseases. A review is made of the different methods used to study heart rate variability, and an account is given of the information provided by spectral methods and the new procedures based on the complex demodulation of the time series composed of consecutive cardiac cycles. The limitations of the spectral methods are deal with, particularly in defining the time-dependent changes in variability and their relation to clinical events. Likewise, a description is given of the ability of complex demodulation to define the time course of the oscillations into which the analyzed time series is decomposed. Complex demodulation based on the fast Fourier transform and its inverse is able to establish the instantaneous amplitude and frequency of each of the oscillations contained in the time series, separated by specific filters in the previously selected frequency bands (high: 0.15-0.40 Hz, low: 0.04-0.15 Hz, or very low: < 0.04 Hz), and from which the original signal may be reconstructed. The evaluation of the different methodological approaches, and the analysis of the causal relations between the variability modifications and clinical events will further extend the clinical relevance of the study of heart rate variability.

[Biatrial thrombosis]. / Trombosis biauricular.

A fifty-eight year old patient presented subacute right heart failure. Transthoracic and transesophageal echocardiography revealed thrombi in both atria, and initial anticoagulation and subsequent surgical treatment were successful. Echocardiography is defined as being decisive to diagnosis, and the role of surgery in the treatment of these patients is commented.

[Effect of the inhalation ++ anesthetic isoflurane on heart electrophysiology]. / Efecto del anestésico inhalatorio isoflurano sobre la electrofisiología cardíaca.

In two groups, A and B, both composed of 10 mongrel dogs, we studied the cardiac electrophysiologic effects of 1 and 1.5 MAC isoflurane administered by liquid injection in a closed circuit. In group B the study was done under pharmacological autonomic blockade (AB). With electrode catheters for programmed pacing and endocavitary potential recordings, we determined during the anesthesia with 1 and 1.5 MAC isoflurane: RR, spontaneous and paced AH, and HV intervals, corrected sinus recovery time (CSRT), Wenckebach point (WP), functional and effective refractory periods of atria (AFRP, AERP) and AV node (AVNFRP, AVNERP), and ventricular effective refractory period (VERP), these were compared to the ones obtained with a previous thiopental control. In group A, 1 MAC isoflurane increased over control: AERP and AH interval (p < 0.05), AFRP (p < 0.005), RR and AH paced intervals, WP, AVNFRP and VERP (p < 0.001), adding to these CSRT (p < 0.01) in 1.5 CAM. This level did not show differences with 1 MAC. In group B, 1 MAC isoflurane increased over control: AH (p < 0.05), RR, paced AH intervals, WP and AVNFRP (p < 0.001), adding to these AFRP and AERP (p < 0.05) in 1.5 MAC. This level increased with regard to 1 MAC: AFRP, AERP, AH paced interval and AVNERP (p < 0.05), and AVNFRP (p < 0.005). Isoflurane alone or with AB increased parameters of sinusal automaticity, atrial refractoriness, AV nodal conduction and refractoriness, increasing only without AB ventricular refractoriness and CSRT. With AB atrial and AV nodal refractoriness increased in an anesthetic depth dependent way.

[Left ventricular pseudoaneurysm. The dynamics and flow patterns analyzed by Doppler echocardiography]. / Seudoaneurisma ventricular izquierdo. Dinámica y patrones de flujo analizados mediante ecocardiografía-Doppler.

A patient with antecedents of ischemic cardiopathy is presented. Echocardiographic exploration revealed the presence of an accessory cavity in connection with the left ventricle behind the basal segment of the posterior left ventricular wall, the characteristics of which were compatible with a ventricular pseudoaneurysm. The Doppler study (both conventional and color coded) allowed us to determine the multiphasic characteristics of the flow between both cavities, and its relation with the variations of volume of the same, as well as with the transmitral and aortic flows. The filling of the pseudoaneurysm was observed to begin before initiation of the ejection through the aorta. Initiation of emptying towards the left ventricular cavity took place in the late systole, and there was a new flow inversion towards the pseudoaneurysm in the early diastole coinciding with the rapid ventricular filling, and therefore before producing the atrial contraction.