Seguimiento a largo plazo tras la ablación con radiofrecuencia de taquicardias ventriculares en pacientes portadores de un desfibrilador automático implantable

Introducción y objetivos. La aparición de episodios frecuentes de taquicardia ventricular es un problema para los pacientes portadores de un desfibrilador implantable y en ocasiones requiere la combinación de un tratamiento antiarrítmico o una ablación con radiofrecuencia. Hemos analizado los resultados de esta técnica en el grupo de pacientes portadores de desfibrilador por taquicardia ventricular sincopal previa que presentaron taquicardia ventricular frecuente o incesante. Pacientes y método. Se realizaron 18 procedimientos de ablación en 11 varones de 67,64 ± 5,87 años con estas características; 10 pacientes habían presentado un infarto de miocardio 15,50 ± 5,08 años antes y otro tenía una displasia arritmogénica del ventrículo derecho. Hasta la ablación se produjeron 591,67 ± 1.020,34 episodios de taquicardia ventricular (rango, 7-2.604). Resultados. El éxito electrofisiológico inicial fue del 72,73% (n = 8). Tras un seguimiento de 39,10 ± 24,70 meses, el número de descargas del desfibrilador disminuyó significativamente en todos los pacientes y pasó de 52,82 ± 35,73 (rango, 7-130) a 0,64 ± 1,03 (rango, 0-3) (p = 0,001); 9 pacientes presentaron posteriormente alguna taquicardia ventricular; 6 enfermos necesitaron nuevos intentos de ablación (2 por fracaso inicial, 3 por recurrencia y 1 por una taquicardia diferente). Con independencia del resultado electrofisiológico, todos los pacientes presentaron buena evolución clínica a largo plazo. Conclusiones. La ablación con radiofrecuencia interrumpe de manera eficaz la situación de taquicardia ventricular incesante o muy recurrente y reduce significativamente las descargas del desfibrilador, incluso tras el fracaso electrofisiológico, y es especialmente útil en estas situaciones críticas, cuando otras terapias resultan ineficaces o insuficientes. Dado que nuestros pacientes son mayoritariamente isquémicos y muy proclives a presentar nuevos eventos arrítmicos durante su seguimiento, la ablación no se consideró sustitutiva, sino complementaria del desfibrilador implantable

Sex-Specific Ventricular Arrhythmias and Mortality in Cardiac Resynchronization Therapy Recipients

OBJECTIVES The study goal was to examine whether there are sex-related differences in the incidence of ventricular arrhythmias and mortality in CRT-defibrillator (CRT-D) recipients. BACKGROUND Few studies have evaluated sex-related benefits of cardiac resynchronization therapy (CRT). Moreover, data on sex-related differences in the occurrence of ventricular tachyarrhythmias in this population are limited. METHODS A multicenter retrospective study was conducted in 460 patients (355 male subjects and 105 female sub- jects) from the UMBRELLA (Incidence of Arrhythmia in Spanish Population With a Medtronic Implantable Cardiac Defi- brillator Implant) national registry. Patients were followed up through remote monitoring after the first implantation of a CRT-D during a median follow-up of 2.2 1.0 years. Sex differences were analyzed in terms of ventricular arrhythmia– treated incidence and death during the follow-up period, with a particular focus on primary prevention patients. RESULTS Baseline New York Heart Association functional class was worse in women compared with that in men (67.0% of women in New York Heart Association functional class III vs. 49.7% of men; p ¼ 0.003), whereas women had less ischemic cardiac disease (20.8% vs. 41.7%; p < 0.001). Female sex was an independent predictor of ventricular ar- rhythmias (hazard ratio: 0.40; 95% confidence interval: 0.19 to 0.86; p ¼ 0.020), as well as left ventricular ejection fraction and nonischemic cardiomyopathy. Mortality in women was one-half that of men, although events were scarce and without significant differences (2.9% vs. 5.6%; p ¼ 0.25). CONCLUSIONS Women with left bundle branch block and implanted CRT have a lower rate of ventricular tachyarrhythmias than men. All-cause mortality in patients is, at least, similar between female and male subjects.Medicin

Personalized monitoring of electrical remodelling during atrial fibrillation progression via remote transmissions from implantable devices.

Atrial electrical remodelling (AER) is a transitional period associated with the progression and long-term maintenance of atrial fibrillation (AF). We aimed to study the progression of AER in individual patients with implantable devices and AF episodes. Observational multicentre study (51 centres) including 4618 patients with implantable cardioverter-defibrillator +/-resynchronization therapy (ICD/CRT-D) and 352 patients (2 centres) with pacemakers (median follow-up: 3.4 years). Atrial activation rate (AAR) was quantified as the frequency of the dominant peak in the signal spectrum of AF episodes with atrial bipolar electrograms. Patients with complete progression of AER, from paroxysmal AF episodes to electrically remodelled persistent AF, were used to depict patient-specific AER slopes. A total of 34 712 AF tracings from 830 patients (87 with pacemakers) were suitable for the study. Complete progression of AER was documented in 216 patients (16 with pacemakers). Patients with persistent AF after completion of AER showed ∼30% faster AAR than patients with paroxysmal AF. The slope of AAR changes during AF progression revealed patient-specific patterns that correlated with the time-to-completion of AER (R2 = 0.85). Pacemaker patients were older than patients with ICD/CRT-Ds (78.3 vs. 67.2 year olds, respectively, P < 0.001) and had a shorter median time-to-completion of AER (24.9 vs. 93.5 days, respectively, P = 0.016). Remote transmissions in patients with ICD/CRT-D devices enabled the estimation of the time-to-completion of AER using the predicted slope of AAR changes from initiation to completion of electrical remodelling (R2 = 0.45). The AF progression shows patient-specific patterns of AER, which can be estimated using available remote-monitoring technology.The Centro Nacional de Investigaciones Cardiovasculares (CNIC) is supported by the Instituto de Salud Carlos III (ISCIII), the Ministerio de Ciencia, Innovacion y Universidades (MCNU), and the Pro CNIC Foundation and is a Severo Ochoa Center of Excellence (SEV-2015–0505). This study was supported by grants from the Fondo Europeo de Desarrollo Regional (CB16/11/00458) and the Spanish MCNU (SAF2016-80324-R). The study was also partially supported by the Fundacion Interhospitalaria para la Investigacion Cardiovascular (FIC, Madrid, Spain) and the Heart Rhythm Association of the Spanish Society of Cardiology (D.F.-R., J.J.G.-F.). J.J. is supported by R01 Grant HL122352 from the National Heart Lung and Blood Institute, USA National Institutes of Health.S

Personalized monitoring of electrical remodelling during atrial fibrillation progression via remote transmissions from implantable devices.

Atrial electrical remodelling (AER) is a transitional period associated with the progression and long-term maintenance of atrial fibrillation (AF). We aimed to study the progression of AER in individual patients with implantable devices and AF episodes. Observational multicentre study (51 centres) including 4618 patients with implantable cardioverter-defibrillator +/-resynchronization therapy (ICD/CRT-D) and 352 patients (2 centres) with pacemakers (median follow-up: 3.4 years). Atrial activation rate (AAR) was quantified as the frequency of the dominant peak in the signal spectrum of AF episodes with atrial bipolar electrograms. Patients with complete progression of AER, from paroxysmal AF episodes to electrically remodelled persistent AF, were used to depict patient-specific AER slopes. A total of 34 712 AF tracings from 830 patients (87 with pacemakers) were suitable for the study. Complete progression of AER was documented in 216 patients (16 with pacemakers). Patients with persistent AF after completion of AER showed ∼30% faster AAR than patients with paroxysmal AF. The slope of AAR changes during AF progression revealed patient-specific patterns that correlated with the time-to-completion of AER (R2 = 0.85). Pacemaker patients were older than patients with ICD/CRT-Ds (78.3 vs. 67.2 year olds, respectively, P < 0.001) and had a shorter median time-to-completion of AER (24.9 vs. 93.5 days, respectively, P = 0.016). Remote transmissions in patients with ICD/CRT-D devices enabled the estimation of the time-to-completion of AER using the predicted slope of AAR changes from initiation to completion of electrical remodelling (R2 = 0.45). The AF progression shows patient-specific patterns of AER, which can be estimated using available remote-monitoring technology.The Centro Nacional de Investigaciones Cardiovasculares (CNIC) is supported by the Instituto de Salud Carlos III (ISCIII), the Ministerio de Ciencia, Innovacion y Universidades (MCNU), and the Pro CNIC Foundation and is a Severo Ochoa Center of Excellence (SEV-2015–0505). This study was supported by grants from the Fondo Europeo de Desarrollo Regional (CB16/11/00458) and the Spanish MCNU (SAF2016-80324-R). The study was also partially supported by the Fundacion Interhospitalaria para la Investigacion Cardiovascular (FIC, Madrid, Spain) and the Heart Rhythm Association of the Spanish Society of Cardiology (D.F.-R., J.J.G.-F.). J.J. is supported by R01 Grant HL122352 from the National Heart Lung and Blood Institute, USA National Institutes of Health.S

Reablation in Atrial Fibrillation Recurrence and Pulmonary Vein Reconnection: Cryoballoon versus Radiofrequency as Index Ablation Procedures.

Pulmonary vein (PV) isolation is a well-established rhythm control therapy in atrial fibrillation (AF). Currently, there is no consensus on which ablation technique to use for the first procedure, cryoballoon (CB) or radiofrequency (RF). A retrospective cohort study was conducted on 1055 patients who underwent a first ablation, to assess both techniques based on the need for reablation. Patients with CB (n = 557) and RF (n = 498) ablations were clinically characterized and the need for reablation during a 30-month follow-up was used as the primary endpoint. Independent variables were analyzed to identify potential predictors. The need for reablation was significantly lower in the CB group than in the RF group (hazard ratio = 0.45 and 95% confident interval = 0.32−0.61;

Distinct spectral dynamics of implanted cardiac defibrillator signals in spontaneous termination of polymorphic ventricular tachycardia and fibrillation in patients with electrical and structural diseases.

To determine the spectral dynamics of early spontaneous polymorphic ventricular tachycardia and ventricular fibrillation (PVT/VF) in humans. Fifty-eight self-terminated and 173 shock-terminated episodes of spontaneously initiated PVT/VF recorded by Medtronic implanted cardiac defibrillators (ICDs) in 87 patients with various cardiac pathologies were analyzed by short fast Fourier transform of shifting segments to determine the dynamics of dominant frequency (DF) and regularity index (RI). The progression in the intensity of DF and RI accumulations further quantified the time course of spectral characteristics of the episodes. Episodes of self-terminated PVT/VF lasted 8.6 s [95% confidence interval (CI): 8.1-9.1] and shock-terminated lasted 13.9 s (13.6-14.3) (P Consistent with the notion that fast organized sources maintain PVT/VF in humans, reduction of frequency and regularity correlates with early self-termination. Our findings might help generate ICD methods aiming to reduce inappropriate shock deliveries