Innovations and paradigm shifts in atrial fibrillation ablation

Treatment of symptomatic atrial fibrillation has seen important changes in the past decades. Advancements have especially been made in the field of non-pharmacological treatment of this disease. Patients in whom a rhythm control strategy is chosen the place of catheter ablation has become more frontline therapy in the past years. The procedure itself has also seen changes in technologies that can be used, either using point-by-point radiofrequency or one of the single-shot techniques. One of the major limitations that remain is that re-do procedures are often necessary due to incomplete pulmonary vein isolation and/or atrial fibrillation being initiated by other mechanisms than pulmonary vein triggers. Therefore, there is further need for developing ablation tools that reproducibly isolate the pulmonary vein transmurally. Furthermore, addressing the underlying conditions before and after catheter ablation has been shown to be of great importance. In this review, we will give an overview of the evolution of catheter ablation, highlight the latest technologies and their future endeavours, and lifestyle modifications are being discussed as part of the catheter ablation strategy

Rate control drugs differ in the prevention of progression of atrial fibrillation

AIMS: We hypothesize that in patients with paroxysmal atrial fibrillation (AF), verapamil is associated with lower AF progression compared to beta blockers or no rate control. METHODS AND RESULTS: In this pre-specified post hoc analysis of the RACE 4 randomized trial, the effect of rate control medication on AF progression in paroxysmal AF was analysed. Patients using Vaughan-Williams Class I or III antiarrhythmic drugs were excluded. The primary outcome was a composite of first electrical cardioversion (ECV), chemical cardioversion (CCV), or atrial ablation. Event rates are displayed using Kaplan–Meier curves and multivariable Cox regression analyses are used to adjust for baseline differences. Out of 666 patients with paroxysmal AF, 47 used verapamil, 383 used beta blockers, and 236 did not use rate control drugs. The verapamil group was significantly younger than the beta blocker group and contained more men than the no rate control group. Over a mean follow-up of 37 months, the primary outcome occurred in 17% in the verapamil group, 33% in the beta blocker group, and 33% in the no rate control group (P = 0.038). After adjusting for baseline characteristics, patients using verapamil have a significantly lower chance of receiving ECV, CCV, or atrial ablation compared to patients using beta blockers [hazard ratio (HR) 0.40, 95% confidence interval (CI) 0.19–0.83] and no rate control (HR 0.64, 95% CI 0.44–0.93). CONCLUSION: In patients with newly diagnosed paroxysmal AF, verapamil was associated with less AF progression, as compared to beta blockers and no rate control

Mobile app-based symptom-rhythm correlation assessment in patients with persistent atrial fibrillation

Background: The assessment of symptom-rhythm correlation (SRC) in patients with persistent atrial fibrillation (AF) is challenging. Therefore, we performed a novel mobile app-based approach to assess SRC in persistent AF.Methods: Consecutive persistent AF patients planned for electrical cardioversion (ECV) used a mobile app to record a 60-s photoplethysmogram (PPG) and report symptoms once daily and in case of symptoms for four weeks prior and three weeks after ECV. Within each patient, SRC was quantified by the SRC-index defined as the sum of symptomatic AF recordings and asymptomatic non-AF recordings divided by the sum of all recordings.Results: Of 88 patients (33% women, age 68 +/- 9 years) included, 78% reported any symptoms during recordings. The overall SRC-index was 0.61 (0.44-0.79). The study population was divided into SRC-index tertiles: low (= 0.73). Patients within the low (vs high) SRC-index tertile had more often heart failure and diabetes mellitus (both 24.1% vs 6.9%). Extrasystoles occurred in 19% of all symptomatic non-AF PPG recordings. Within each patient, PPG recordings with the highest (vs lowest) tertile of pulse rates conferred an increased risk for symptomatic AF recordings (odds ratio [OR] 1.26, 95% coincidence interval [CI] 1.04-1.52) and symptomatic non-AF recordings (OR 2.93, 95% CI 2.16-3.97). Pulse variability was not associated with reported symptoms.Conclusions: In patients with persistent AF, SRC is relatively low. Pulse rate is the main determinant of reported symptoms. Further studies are required to verify whether integrating mobile app-based SRC assessment in current workflows can improve AF management

Risk Factors for Atrial Fibrillation Progression

Atrial fibrillation is a chronic, progressive condition that presents a major health burden. This review summarizes recent studies assessing atrial fibrillation progression and its associated risk factors, describes the mechanisms underlying atrial fibrillation progression, and discusses the clinical implications of the progressive nature of atrial fibrillation. Progression of atrial fibrillation burden, and clinical progression from paroxysmal to more advanced (persistent/permanent) forms is common, but progression rates are variable. Atrial fibrillation progression parallels progressive atrial remodeling induced by atrial fibrillation risk factors and atrial fibrillation itself, and is associated with worse clinical outcomes

Epicardial box lesion using bipolar biparietal radiofrequency and multimodality scar evaluation-a case series

BACKGROUND: Surgical epicardial atrial fibrillation (AF) ablation can be performed as a stand-alone (thoracoscopic) procedure or concomitant to other cardiac surgery. In hybrid AF ablation thoracoscopic surgical epicardial ablation is combined with a percutaneous endocardial ablation. The Medtronic Gemini-S clamp is a surgical tool that uses irrigated bipolar biparietal radiofrequency (RF) energy applied with two clamp lesions that overlap to create one epicardial box lesion including the posterior left atrial wall and the pulmonary veins. CASE SUMMARY: We describe three patients with therapy-refractory persistent AF and different stages of atrial remodelling in whom the Medtronic Cardioblate Gemini-S Irrigated RF Surgical Ablation System was used for hybrid AF ablation. Acute endocardial validation at the end of the hybrid ablation revealed a complete box lesion in all three cases. At 2-year follow-up, two out of three patients had recurrence of atrial arrhythmias. Invasive electro-anatomical mapping confirmed the persistence of the box lesion, and the mechanism of arrhythmia recurrence in both patients was unrelated to posterior left atrium or the pulmonary veins. The third patient has been without arrhythmia symptoms since the ablation procedure. A three-dimensional late gadolinium enhancement magnetic resonance imaging illustrates the ablation scar non-invasively in two cases. DISCUSSION: Thoracoscopic biparietal RF AF ablation with the Medtronic Cardioblate Gemini-S Irrigated RF Surgical Ablation System results in permanent transmural scar formation, irrespective of the stage of atrial remodelling, as shown in this small population by means of multimodality scar evaluation