Feasibility and safety of left atrial posterior wall isolation with a new Cryoballoon technology in patients with persistent atrial fibrillation.

BACKGROUND: Left atrial posterior wall isolation (LAPWI) is often performed in addition to pulmonary vein isolation (PVI) in the setting of persistent atrial fibrillation (AF) ablation. The aim of this study was to evaluate the feasibility and safety of a new cryoballoon ablation system in achieving PVI + LAPWI isolation. METHODS: The study was a prospective, non-randomized, single center study. Forty consecutive patients, undergoing PVI + LAPWI with the novel POLARx™, were compared to 40 consecutive patients who underwent the same procedure with the established Arctic Front Advance PRO™. RESULTS: Acute isolation was achieved in all PVs in both groups and left posterior wall isolation (LAPWI) was achieved in 38 patients (95%) in the POLARx group and in 36 patients (90%) in Arctic Front group. Procedural outcomes were similar between both groups, except for lower temperatures during cryoenergy in the POLARx group, for both pulmonary vein isolation (PVI) and LAPWI. CONCLUSION: LAPWI + PVI with the novel POLARx™ Cryoballoon is feasible and safe; the results are comparable with the Arctic Front Advance PRO™ system.

Cryoballoon ablation vs. antiarrhythmic drugs: first-line therapy for patients with paroxysmal atrial fibrillation.

AIMS: Treatment guidelines for patients with atrial fibrillation (AF) suggest that patients should be managed with an antiarrhythmic drug (AAD) before undergoing catheter ablation (CA). This study evaluated whether pulmonary vein isolation employing cryoballoon CA is superior to AAD therapy for the prevention of atrial arrhythmia (AA) recurrence in rhythm control naive patients with paroxysmal AF (PAF). METHODS AND RESULTS: A total of 218 treatment naive patients with symptomatic PAF were randomized (1 : 1) to cryoballoon CA (Arctic Front Advance, Medtronic) or AAD (Class I or III) and followed for 12 months. The primary endpoint was ≥1 episode of recurrent AA (AF, atrial flutter, or atrial tachycardia) >30 s after a prespecified 90-day blanking period. Secondary endpoints included the rate of serious adverse events (SAEs) and recurrence of symptomatic palpitations (evaluated via patient diaries). Freedom from AA was achieved in 82.2% of subjects in the cryoballoon arm and 67.6% of subjects in the AAD arm (HR = 0.48, P = 0.01). There were no group differences in the time-to-first (HR = 0.76, P = 0.28) or overall incidence [incidence rate ratio (IRR)=0.79, P = 0.28] of SAEs. The incidence rate of symptomatic palpitations was lower in the cryoballoon (7.61 days/year) compared with the AAD arm (18.96 days/year; IRR = 0.40, P < 0.001). CONCLUSIONS: Cryoballoon CA was superior to AAD therapy, significantly reducing AA recurrence in treatment naive patients with PAF. Additionally, cryoballoon CA was associated with lower symptom recurrence and a similar rate of SAEs compared with AAD therapy.

Standardized Quantification of Vagal Denervation by Extracardiac Vagal Stimulation during Second Generation Cryoballoon ablation: a Vein per Vein Analysis.

AIMS: The purpose of this study was to evaluate the contribution in the acute loss in vagal innervation after ablation with the second generation cryoballoon (CB-A) in each distinct pulmonary vein (PV) by means of external cardiac vagal stimulation (ECVS) by positioning a catheter in the internal jugular vein in a cohort of 60 patients. METHODS: Sixty patients, 50 starting from the left superior pulmonary vein (LSPV) and 10 from the right superior pulmonary vein with symptomatic paroxysmal atrial fibrillation (PAF), having undergone ECVS before the first and after each PV ablation by means of CB-A ablation, were included. RESULTS: The ECVS performed pre-ablation provoked cardioinhibitory responses in all cases with mean pause duration of 10251.83 ms ± 2826.23 ms. At the end of the procedure, the vagal reactions (VR) were significantly diminished. Specifically, compared against the initial pause, responses were 8957.06 ± 2711.66 ms (p < 0.01) after left superior PV, 10017.36 ± 9127.0 ms (p = 0.88) after left inferior PV, 6020.16 ± 3780.709 ms (p < 0.001) after right inferior PV and 1687.5 ± 2183.7 ms (p < 0.001) after right superior PV. Noteworthy, if starting with ablation in the RSPV, VR was immediately reduced by 90.34%, 990.7 ± 379.78 ms (p < 0.001) as compared to baseline response. CONCLUSION: Although not directly targeting the ganglion plexuses, AF ablation with the CB-A causes a significant acute loss in parasympathetic innervation. The RSPV showed to be associated with the most significant reduction of acute loss in parasympathetic innervation.

Trascendencia clínica del embarazo en el síndrome de Brugada / The Clinical Significance of Pregnancy in Brugada Syndrome

Introducción y objetivos: Se sabe poco sobre los riesgos y los resultados del embarazo en mujeres con síndrome de Brugada. Por lo tanto, se evalúa la influencia del embarazo en pacientes con síndrome de Brugada. Métodos: Se realizó un análisis retrospectivo de todas las embarazadas con síndrome de Brugada. Se incluyó a 104 mujeres con un total de 219 partos. Resultados: Hubo 15 abortos espontáneos; 1 niño falleció súbitamente durante la noche 3 meses después del nacimiento; 6 embarazadas refirieron haber sufrido al menos un síncope durante el embarazo; en ninguna de las 3 mujeres a las que se implantó un desfibrilador automático implantable antes del embarazo se registraron episodios arrítmicos; 4 pacientes con antecedente de muerte súbita cardiaca recuperada no sufrieron evento alguno durante el embarazo. De las 24 pacientes que habían sufrido síncopes cuando no estaban embarazadas, 18 se mantuvieron asintomáticas y 6 sufrieron síncope durante el embarazo. Durante el seguimiento (media, 298,9 días; intervalo de confianza del 95%, 289,6-308,2) 2 mujeres recibieron descargas apropiadas. Conclusiones: En este estudio unicéntrico y retrospectivo, los eventos graves no fueron más frecuentes durante el embarazo y el periodo periparto en las mujeres con síndrome de Brugada. La aparición de síncopes durante el embarazo no se asoció a una peor evolución en los periodos periparto y posparto ni durante el seguimiento. La tasa descrita de abortos espontáneos y muerte súbita infantil deberá investigarse en nuevos estudios para confirmar o descartar su asociación con el síndrome de Brugada (AU)

Introduction and objectives: Little is known about the risks and outcomes of pregnancy in women with Brugada syndrome. We therefore evaluated pregnancy outcomes and the influence of pregnancy in patients with Brugada syndrome. Methods: A retrospective analysis was performed in all pregnant women with Brugada syndrome. We included 104 women with a total of 219 deliveries. Results: There were 15 spontaneous abortions. One infant died suddenly during the night 3 months after birth. Six pregnant women reported they had experienced at least 1 syncope during the pregnancy. Of the 3 women who received an implantable cardioverter-defibrillator before the pregnancy, none received arrhythmia episodes. There were no events during the pregnancy in 4 patients with a previously aborted sudden cardiac death. Of 24 patients with syncope when not pregnant, 18 were asymptomatic and 6 experienced a recurrent syncope during the pregnancy. During the follow-up (mean follow-up 298.9 days; 95% confidence interval, 289.6-308.2), 2 women received appropriate shocks. Conclusions: In this retrospective, single-center study, serious events were not more frequent during pregnancy and the peripartum period in women with Brugada syndrome. The occurrence of syncope during pregnancy was not associated with a worst outcome in the peri- and postpartum periods or during follow-up. The reported rate of miscarriage and sudden infant death will require further studies to confirm or rule out its association with Brugada syndrome (AU)

Epidemiología de la muerte súbita cardiaca / Epidemiology of sudden cardiac death

A pesar de los recientes avances en el tratamiento de los trastornos cardiovasculares en general y de las arritmias en particular, la muerte súbita cardiaca continúa siendo tanto un problema para el médico como un tema de salud pública de gran relevancia. Se estima que la incidencia anual de muerte súbita cardiaca en todo el mundo oscila entre 4 y 5 millones de casos al año. La información disponible sobre las causas y los mecanismos del síndrome de muerte súbita cardiaca revelan que para reducirla será necesario desarrollar nuevos y múltiples enfoques, entre ellos técnicas epidemiológicas para abordar las características de riesgo específicas, la caracterización de los sucesos desencadenantes y la identificación de personas concretas con riesgo de responder mal a estos sucesos, así como métodos adecuados para evaluar la evolución clínica tras un episodio de muerte súbita cardiaca (AU)

Despite recent progress in the management of cardiovascular disorders generally, and cardiac arrhythmias in particular, sudden cardiac death remains both a problem for the practising clinician and a major public health issue. An estimate for global annual incidence of sudden cardiac death would be in the range of 4 to 5 million cases per year. Information about the causes and mechanisms of the sudden cardiac death syndrome suggests that a specific reduction will require the development of new and multifaceted approaches, including epidemiologic techniques to address risk characteristics specific to the problem; characterisation of triggering events and identification of specific persons at risk for responding adversely to these events; and methods of evaluating outcomes appropriate to the nature of sudden cardiac death (AU)