Alejandro Cuesta

Nonsurgical transthoracic epicardial radiofrequency ablation. an alternative in incessant ventricular tachycardia

OBJECTIVES The purpose of this study was to analyze the feasibility, efficacy, and safety of epicardial radiofrequency (RF) ablation in patients with incessant ventricular tachycardia (VT). BACKGROUND Management of patients with incessant VT is a difficult clinical problem. Drugs and RF catheter ablation are not always effective. A nonsurgical transthoracic epicardial RF ablation can be an alternative in patients refractory to conventional therapy. METHODS Epicardial RF ablation was performed in 10 patients who presented with incessant VT despite the use of two or more intravenous antiarrhythmic drugs. RESULTS In eight patients, endocardial ablation (EdA) failed to control the tachycardia. In the remaining two patients, epicardial ablation (EpA) was first attempted because of left ventricular thrombus and severe artery disease, respectively. Eight patients had a diagnosis of coronary artery disease with healed myocardial infarction. One patient had dilated cardiomyopathy, and one patient had idiopathic, incessant VT. In patients with structural heart disease, the mean ejection fraction was 0.28 +/- 0.10%. Four patients previously received an implantable defibrillator. The EpA effectively terminated the incessant tachycardia in eight patients, which represents a success rate of 80%. In them, after a follow-up of 18 +/- 18 months, a single episode of a different VT was documented in one patient. No significant complications occurred related to the procedure. CONCLUSIONS In patients with incessant VT despite the use of drugs or standard EdA, the epicardial approach was very effective and should be considered as an alternative in this life-threatening situation.

Catéter de 8 mm frente a punta irrigada en la ablación del flutter auricular dependiente del istmo: un estudio prospectivo y aleatorizado

Introduccion y objetivos. En la ablacion del flutter auricular tipico se utilizan cateteres con puntas de 8 mm e irrigadas para mejorar los resultados; sin embargo, la mejor opcion aun no esta establecida. Quisimos comparar la efectividad de un cateter de 8 mm (grupo 1) y uno irrigado abierto (grupo 2) en el primer intento de ablacion. Metodos. Realizamos un estudio prospectivo, aleatorizado y con seguimiento a largo plazo, incluyendo a pacientes con flutter tipico documentado. Para ambos cateteres se programo inicialmente una potencia de 50 W. El objetivo primario fue lograr la ablacion del istmo cavotricuspideo con 600 s de aplicacion como maximo. Resultados. Se incluyo a 65 pacientes en el grupo 1 y 66 en el grupo 2 sin diferencias significativas en las caracteristicas basales. La media de edad era 63 ± 12 anos; el 80% eran varones y el 65% tenia cardiopatia estructural. Alcanzaron el punto final primario 48 (73,8%) pacientes del grupo 1 y 49 (74,2%) del grupo 2. En los restantes pacientes se continuo segun el criterio del operador y la ablacion fue efectiva en todos. Por intencion de tratamiento no hubo diferencias significativas en el numero de aplicaciones ni en los tiempos de aplicacion, radioscopia y el total del procedimiento. A los 16 ± 5 meses de seguimiento (el 98%, mas de 1 ano) hubo 8 (6,3%) pacientes con recurrencia y 95 (74,2%) libres de toda arritmia, sin diferencia entre ambos grupos. Conclusiones. No encontramos diferencia en la efectividad entre un cateter de 8 mm y uno irrigado abierto en la primera intencion de ablacion del flutter auricular comun.

Comparison of 8-mm-Tip and Irrigated-Tip Catheters in the Ablation of Isthmus-Dependent Atrial Flutter: a Prospective Randomized Trial

INTRODUCTION AND OBJECTIVES Both 8-mm-tip and irrigated-tip catheters improve outcomes in typical atrial flutter ablation. However, it is not yet known which is preferable. The objective was to compare the effectiveness of 8-mm-tip (Group 1) and open irrigated-tip (Group 2) catheters in the first ablation attempt. METHODS A prospective randomized trial with a long-term follow-up was performed in patients with documented typical atrial flutter. For both types of catheter, the power was initially set to 50 W. The primary endpoint was ablation of the cavotricuspid isthmus in a procedure lasting, at most, 600 s. RESULTS Group 1 contained 65 patients and Group 2 contained 66, with no significant intergroup difference in baseline characteristics. Their mean age was 63+/-12 years, 80% were men, and 65% had structural heart disease. The primary endpoint was achieved in 48 patients (73.8%) in Group 1 and 49 (74.2%) in Group 2 (P=NS). In the remaining patients, the procedure was continued at the physicians discretion and ablation was finally achieved in all cases. In the intention-to-treat analysis, there was no significant difference between the groups in the number of applications of the ablation device or in the duration of the ablation procedure, radioscopy or the total procedure. By 16+/-5 months of follow-up (>1 year in 98%), 8 (6.3%) patients had experienced recurrence and 95 (74.2%) were free from any arrhythmia. There was no differences between the groups. CONCLUSIONS No difference was found between the effectiveness of 8-mm-tip and open irrigated-tip catheters in the first attempt at ablation of typical atrial flutter.

Molecular autopsy in a cohort of infants died suddenly at rest

Sudden infant death syndrome is the leading cause of death during the first year of life. A large part of cases remains without a conclusive cause of death after complete autopsy. In these situations, cardiac arrhythmia of genetic origin is suspected as the most plausible cause of death. Our aim was to ascertain whether genetic variants associated with sudden cardiac death might be the cause of death in a cohort of infants died suddenly. We analyzed 108 genes associated with sudden cardiac death in 44 post-mortem samples of infants less than 1 year old of age who died at rest. Definite cause of death was not conclusive in any case after a complete autopsy. Genetic analysis identified at least one rare variant in 90.90% of samples. A total of 121 rare genetic variants were identified. Of them, 33.05% were novel and 39.66% were located in genes encoding ion channels or associated proteins. A comprehensive genetic analysis in infants who died suddenly enables the unraveling of potentially causative cardiac variants in 2045% of cases. Molecular autopsy should be included in forensic protocols when no conclusive cause of death is identified. Large part genetic variants remain of uncertain significance, reinforcing the crucial role of genetic interpretation before clinical translation but also in early identification of relatives at risk.