Xavier Sabaté

Washing Machine Associated 50 Hz Detected As Ventricular Fibrillation by An Implanted Cardioverter Defibrillator

SABATÉ, X., et al.: Washing Machine Associated 50 Hz Detected As Ventricular Fibrillation by An Implanted Cardioverter Defibrillator. This case report describes a patient with an automatic ICD who suffered a defibrillation shock without warning symptoms. An electrical interference can be observed in the stored EGM of the episode. The patient explained that the moment he felt the shock he was touching a washing machine. After correct grounding of this machine the patient did not suffer more inappropriate shocks.

The Benefit of a Second Burst Antitachycardia Sequence for Fast Ventricular Tachycardia in Patients with Implantable Cardioverter Defibrillators

In patients with implantable cardioverter defibrillators (ICDs), an empirical burst of antitachycardia pacing (ATP) is moderately effective in terminating fast ventricular tachycardias (FVTs). It is unknown whether, in the case of failure of a first burst, a second burst attempt increases the efficacy of the intervention, without increasing morbidity. Our aim was to evaluate the safety and efficacy of a strategy of programming successive ATP sequences for FVT episodes.

Chronic total occlusion of an infarct-related artery: a new predictor of ventricular arrhythmias in primary prevention implantable cardioverter defibrillator patients

Aims The aim of this article is to evaluate the impact of a coronary chronic total occlusion in an infarct‐related artery (IRA‐CTO) on the occurrence of ventricular arrhythmias (VAs) in patients implanted with an implantable cardioverter defibrillator (ICD) for primary prevention. Methods and results The study includes a prospective cohort of 108 consecutive patients with ischaemic cardiomyopathy, in whom an ICD was implanted for primary prevention and a coronary angiography performed before ICD implantation. About 49 patients (45%) had a CTO and 34 (31%) had an IRA‐CTO. Patients with IRA‐CTO did not differ from the rest of the population in terms of basal characteristics and severity of cardiac disease. Median follow‐up was 33 months (interquartile range 46). Infarct‐related artery‐CTO was associated with higher rates of any VA (53 vs. 26%, P = 0.006) and fast ventricular tachycardia (fast VT, cycle length <300 ms) or ventricular fibrillation (VF) (47 vs. 19%, P = 0.002). At multivariate Cox regression, IRA‐CTO was the only independent predictor of any VA [hazard ratio (HR) 3.64, P = 0.002] and fast VT/VF (HR 3.36, P = 0.008). On the contrary, CTO not associated with a prior infarction in their territory did not increase the risk of VA. Infract‐related artery‐CTO was also an independent predictor of cardiac mortality or heart transplantation (HR 3.46, P = 0.022). Conclusion In ischaemic patients implanted with an ICD for primary prevention, a CTO associated with a previous infarction in its territory is an independent predictor of VA and, especially, of fast VT/VF, identifying a subgroup of patients with a very high rate of arrhythmic events at follow‐up.

Morphology of Far-Field Electrograms and Antitachycardia Pacing Effectiveness Among Fast Ventricular Tachycardias Occurring in ICD Patients: A Multicenter Study

Fast ventricular tachycardias (FVT) are less likely to be terminated by antitachycardia pacing (ATP). No information is available regarding the ability of far‐field electrogram (Ff‐EG) morphology (Ff‐EGm) in predicting the result of the subsequent ATP. Our objective is to determine the relationship between Ff‐EGm and ATP efficacy.

Fatal undersensing of ventricular fibrillation due to intermittent high-amplitude R waves.

A 48‐year‐old man was admitted after an episode of aborted sudden death with external defibrillation. An implantable cardioverter defibrillator implanted 2 years before for secondary prevention failed to sense properly an episode of ventricular fibrillation. Interrogation of the device showed large oscillatory changes of the amplitude of the local electrogram during ventricular fibrillation, causing undersensing and inappropriate refraining from shock therapy. (PACE 2012; 35:e284–e286)

Trends in the use of electrical cardioversion for atrial fibrillation: influence of major trials and guidelines on clinical practice.

BackgroundThe purpose of the present study was to assess the trends in the use of ECV following published studies that had compared rhythm and rate control strategies on atrial fibrillation (AF), and the recommendations included in the current clinical practice guidelines.MethodsThe REVERCAT is a population-based assessment of the use of electrical cardioversion (ECV) in treating persistent AF in Catalonia (Spain). The initial survey was conducted in 2003 and the follow-up in 2010.ResultsWe observed a decrease of 9% in the absolute numbers of ECV performed (436 in 2003 vs. 397 in 2010). This is equivalent to 27% when considering population increases over this period. The patients treated with ECV in 2010 were younger, had a lower prevalence of previous embolism, a higher prevalence of diabetes, and increased body weight. Underlying heart disease factors indicated, in 2010, a higher proportion of NYHA ≥ II and left ventricular ejection fraction <30%. We observed a reduction in the number of ECV performed in 16 of the 27 (67%) participating hospitals. However, there was an increase of 14% in the number of procedures performed in tertiary hospitals, and was related to the increasing use of ECV as a bridge to AF ablation. Considering the initial number of patients treated with ECV, the rate of sinus rhythm at 3 months was almost unchanged (58% in 2003 vs. 57% in 2010; p = 0.9) despite the greater use of biphasic energy in 2010 and a similar prescription of anti-arrhythmic drugs.ConclusionsAlthough we observed a decrease in the number of ECVs performed over the 7 year period between the two studies, this technique remains a common option for treating patients with persistent AF. The change in the characteristics of candidate patients did not translate into better outcomes.

Utilidad en la práctica clínica del tratamiento antiarrítmico tras cardioversión eléctrica en pacientes sin cardiopatía estructural

Introduccion y objetivos Conocer en la practica clinica el uso de antiarritmicos tras cardioversion electrica en pacientes sin cardiopatia y su repercusion en el mantenimiento del ritmo sinusal. Metodos Se realizo un seguimiento a un ano de 528 pacientes con fibrilacion auricular persistente sin cardiopatia significativa tras una cardioversion electrica efectiva en 96 hospitales espanoles, con controles clinicos 1, 3, 6 y 12 meses despues. Se analizo el uso y la utilidad de los farmacos antiarritmicos en la prevencion de recurrencias de fibrilacion auricular persistente. Resultados Se trato al alta con farmacos antiarritmicos al 80% de los pacientes, y el mas utilizado fue la amiodarona. Ningun factor clinico se relaciono con un mayor uso de antiarritmicos. El 37% de los pacientes siguio en ritmo sinusal en todos los controles. En el control a los 12 meses, se mantuvo el tratamiento antiarritmico al 59% de los pacientes que seguian en ritmo sinusal. En el analisis multivariable de la regresion de Cox, el peso (hazard ratio [HR] por cada kilo = 1,01; p = 0,04) y la ausencia de tratamiento antiarritmico (HR = 1,59; p = 0,001) fueron factores independientes relacionados con la recurrencia de fibrilacion auricular persistente. La amiodarona tendia a ser superior a los otros antiarritmicos. Conclusiones En la practica clinica habitual, tras una cardioversion electrica efectiva, la gran mayoria de los pacientes sin cardiopatia estructural recibe farmacos antiarritmicos, especialmente amiodarona, que es el principal factor relacionado con el mantenimiento del ritmo sinusal 1 ano mas tarde.

Aortic Perforation by Active-Fixation Atrial Pacing Lead: An Unusual but Serious Complication

Perforation of a cardiac chamber is an infrequent but serious sequela of pacemaker lead implantation. An even rarer event is the perforation of the aorta by a protruding right atrial wire. We present here the first case in the medical literature of aortic perforation as a sequela to the implantation of a cardiac resynchronization therapy defibrillator. The patient was a 54-year-old man with idiopathic dilated cardiomyopathy who underwent the implantation of a defibrillator, with no apparent sequelae. Six hours after the procedure, he experienced cardiac tamponade and required urgent open-chest surgery. The pericardial effusion was found to be caused by mechanical friction of a protruding right atrial wire on the aortic root. The aortic root and the atrial wall were both repaired with Prolene suture, which achieved complete control of the bleeding. There was no need to reposition the atrial wire. The patient had a good postoperative recovery.

Impact of previous cardiac surgery on long-term outcome of cavotricuspid isthmus-dependent atrial flutter ablation

AIMS The aim of this study was to determine the acute and long-term outcome of radiofrequency catheter ablation (RFCA) for cavotricuspid isthmus-dependent atrial flutter (CTI-AFL) in adults with and without previous cardiac surgery (PCS), and predictors of these outcomes. Structural alterations of the anatomical substrate of the CTI-AFL are observed in post-operative patients, and these may have an impact on the acute success of the ablation and in the long-term. METHODS AND RESULTS Clinical records of consecutive adults undergoing RFCA of CTI-AFL were analysed. Two main groups were considered: No PCS and PCS patients, who were further subdivided into acquired heart disease (AHD: ischaemic heart disease and valvular/mixed heart disease) and congenital heart disease [CHD: ostium secundum atrial septal defect (OS-ASD) and complex CHD]. Multivariate analysis identified clinical and procedural factors that predicted acute and long-term outcomes. A total of 666 patients (73% men, age 65 ± 12 years) were included: 307 of them with PCS. Ablation was successful in 647 patients (97%), 96% in the PCS group and 98% in the No PCS group (P = 0.13). Regression analysis showed that surgically corrected complex CHD was related to failure of the procedure [odds ratio 5.6; 95% confidence interval (CI) 1.6-18, P = 0.008]. After a follow-up of 45 ± 15 months, recurrences were observed in 90 patients (14%), more frequently in the PCS group: absolute risk of recurrence 18 vs. 10.5%, relative risk 1.71, 95% CI: 1.2-2.5, P = 0.006. Multivariate analysis indicated that the types of PCS [OS-ASD vs. No PCS: hazard ratio (HR) 2.57; 95% CI: 1.1-6.2, P = 0.03 and complex CHD vs. No PCS: HR 2.75; 95% CI: 1.41-5.48, P = 0.004], female gender (HR 1.55; 95% CI: 1.04-2.4, P = 0.048), and severe LV dysfunction (HR 1.36; 95% CI: 1.06-1.67, P = 0.04) were independent predictors of long-term recurrence. CONCLUSION Radiofrequency catheter ablation of CTI-AFL after surgical correction of AHD and CHD is associated with high acute success rates. The severity of the structural alterations of the underlying heart disease and consequently the type of surgical correction correlates with higher risk for recurrence.

Shock Reduction With Antitachycardia Pacing Before and During Charging for Fast Ventricular Tachycardias in Patients With Implantable Defibrillators

INTRODUCTION AND OBJECTIVES Fast ventricular tachycardias in the ventricular fibrillation zone in patients with an implantable cardioverter-defibrillator are susceptible to antitachycardia pacing (ATP) termination. Some manufacturers allow programming 2 ATP bursts: before charging (BC) and during (DC) charging. The aim of this study was to describe the safety and effectiveness of ATP BC and DC for fast ventricular tachycardias in the ventricular fibrillation zone in patients with an implantable cardioverter-defibrillator in daily clinical practice. METHODS Data proceeded from the multicenter UMBRELLA trial, including implantable cardioverter-defibrillator patients followed up by the CareLink monitoring system. Fast ventricular tachycardias in the ventricular fibrillation zone until a cycle length of 200ms with ATP BC and/or ATP DC were included. RESULTS We reviewed 542 episodes in 240 patients. Two ATP bursts (BC/DC) were programmed in 291 episodes (53.7%, 87 patients), while 251 episodes (46.3%, 153 patients) had 1 ATP burst only DC. The number of episodes terminated by 1 ATP DC was 139, representing 55.4% effectiveness (generalized estimating equation-adjusted 60.4%). There were 256 episodes terminated by 1 or 2 ATP (BC/DC), representing 88% effectiveness (generalized estimating equation-adjusted 79.3%); the OR for ATP effectiveness BC/DC vs DC was 2.5, 95%CI, 1.5-4.1; P <.001. Shocked episodes were 112 (45%) for ATP DC vs 35 (12%) for ATP BC/DC, representing an absolute reduction of 73%. The mean shocked episode duration was 16seconds for ATP DC vs 19seconds for ATP BC/DC (P=.07). CONCLUSIONS The ATP DC in the ventricular fibrillation zone for fast ventricular tachycardia is moderately effective. Adding an ATP burst BC increases the overall effectiveness, reduces the need for shocks, and does not prolong episode duration.