Anatomic guided ablation of the atrial right ganglionated plexi is enough for cardiac autonomic modulation in patients with significant bradyarrhythmias.

INTRODUCTION: Cardiac autonomic system modulation by endocardial ablation targeting atrial ganglionated plexi (GP) is an alternative strategy in selected patients with severe functional bradyarrhythmias, although no consensus exists on the best ablation strategy. The aim of this study was to evaluate if a simplified approach by a purely anatomical guided ablation of just the atrial right GP is enough for the treatment of these patients. METHODS: We prospectively enrolled patients with significant functional bradyarrhythmias and performed endocardial ablation purely guided by 3D electroanatomic mapping directed at the atrial right GP and accessed parameters of parasympathetic modulation and recurrence of bradyarrhythmias. RESULTS: Thirteen patients enrolled (76.9% male, median age 51, 42-63 years). After ablation, a median RR interval shortening of 28.3 (25.6-40.3)% occurred (1111, 937.5-1395.4 ms to 722.9, 652.2-882.4 ms, p = 0.0002). The AH interval also shortened (19, 10.5-35.7%) significantly after the procedure (115, 105-122 ms to 85, 71-105 ms, p = 0.0023) as well as Wenckebach cycle length (11.1, 5.9-17.8% shortening) from 450, 440-510 ms to 430, 400-460 ms, p = 0.0127. On 24-h Holter monitoring there was significant increase in heart rates (HR) of patients after ablation (minimal HR increased from 34 (26-43)bpm to 49 (43-56)bpm, p = 0,0102 and mean HR from 65 (47-72)bpm to 78 (67-87)bpm, p = 0.0004). No patients had recurrence of symptoms or significant bradyarrhythmias during a median follow-up of 8.4 months. CONCLUSIONS: A purely anatomic guided procedure directed only at the atrial right ganglionated plexi seems to be enough as a therapeutic approach for cardioneuroablation in selected patients with significant functional bradyarrhythmias.

Safety and Long-Term Outcomes of Catheter Ablation of Atrial Fibrillation Using Magnetic Navigation versus Manual Conventional Ablation: A Propensity-Score Analysis.

INTRODUCTION: Whether or not the potential advantages of using a magnetic navigation system (MNS) translate into improved outcomes in patients undergoing atrial fibrillation (AF) ablation is a question that remains unanswered. METHODS AND RESULTS: In this observational registry study, we used propensity-score matching to compare the outcomes of patients with symptomatic drug-refractory AF who underwent catheter ablation using MNS with the outcomes of those who underwent catheter ablation using conventional manual navigation. Among 1,035 eligible patients, 287 patients in each group had similar propensity scores and were included in the analysis. The primary efficacy outcome was the rate of AF relapse after a 3-month blanking period. At a mean follow-up of 2.6 ± 1.5 years, AF ablation with MNS was associated with a similar risk of AF relapse as compared with manual navigation (18.4% per year and 22.3% per year, respectively; hazard ratio 0.81, 95% CI 0.63-1.05; P = 0.108). Major complications occurred in two patients (0.7%) using MNS, and in six patients (2.1%) undergoing manually navigated ablation (P = 0.286). Fluoroscopy times were 21 ± 10 minutes in the manual navigation group, and 12 ± 9 minutes in the MNS group (P < 0.001), whereas total procedure times were 152 ± 52 minutes and 213 ± 58 minutes, respectively (P < 0.001). CONCLUSIONS: In this propensity-score matched comparison, magnetic navigation and conventional manual AF ablations seem to have similar relapse rates and a similar risk of complications. AF ablations with magnetic navigation take longer to perform but expose patients to significantly shorter fluoroscopy times.

Implantable cardioverter-defibrillators in hypertrophic cardiomyopathy.

BACKGROUND: Hypertrophic cardiomyopathy is a genetic disease inherited as an autosomal dominant trait associated with risk of sudden death. The majority of cases of sudden death occur in young adults with no or few symptoms, which underlines the importance of risk stratification as a basis for selecting a therapeutic strategy. Implantable cardioverter-defibrillators are indicated in patients resuscitated following cardiac arrest, and those with sustained ventricular tachycardia or two or more risk factors identified in non-invasive tests. AIM: The aim of this study was to determine the number of appropriate therapies (anti-tachycardia pacing and defibrillation) and the risk factors, or association of risk factors, that predict therapies in patients with hypertrophic cardiomyopathy and an implantable cardioverter-defibrillator. METHODS: We studied 17 consecutive patients with hypertrophic cardiomyopathy and cardioverter-defibrillators implanted between December 1992 and June 2003. The following risk factors were analyzed: 1) previous cardiac arrest or sustained ventricular tachycardia; 2) family history of sudden cardiac death; 3) high-risk genetic mutations; 4) syncope; 5) non-sustained ventricular tachycardia; 6) hypotensive response to exercise; and 7) marked left ventricular hypertrophy. Appropriate therapies were determined and the predictive value of the different sudden death risk stratification parameters was analyzed. RESULTS: During a mean follow-up of 40 +/- 29 months, 7 patients (41%) received a total of 293 appropriate therapies. Of the 9 patients with previous cardiac arrest or ventricular tachycardia, 4 received appropriate therapies. In the remaining 8 patients, with implantable cardioverter-defibrillators for primary prevention, 3 received appropriate therapies. Family history of sudden death was associated with a positive predictive value of 25% for appropriate therapies, 40% for syncope and 50% for non-sustained ventricular tachycardia. The presence of any two risk factors was associated with a positive predictive value of 33% and the presence of three factors with 100%. CONCLUSION: In this group of patients, considered to be at high risk for sudden cardiac death, a considerable percentage had ventricular tachycardias that were correctly identified and treated by the implantable cardioverter-defibrillator. The percentage of patients with appropriate therapies was slightly higher in the group who had a cardioverter-defibrillator for secondary prevention of sudden death (aborted sudden death or sustained ventricular tachycardia). In patients with an implantable cardioverter-defibrillator for primary prevention, non-sustained ventricular tachycardia was the risk factor with the highest predictive value. An association of risk factors was also predictive of arrhythmic events.

Percutaneous ablation of atrial fibrillation: assessment of outcomes at 1-year follow-up.

OBJECTIVE: Current non-pharmacologic treatment strategies for atrial fibrillation (AF) involve discrete ablation of ectopic foci or isolation of the pulmonary vein (PV) ostia, which have been implicated in the genesis of this rhythm disorder. The aim of this study was to determine intermediate and long-term outcomes after percutaneous AF ablation and predictors of successful treatment. POPULATION AND METHODS: We studied 29 consecutive patients (72% male, mean age 52.3 +/- 13 years) who underwent percutaneous ablation of AF refractory to antiarrhythmic drug therapy. AF was idiopathic in 22 patients and the remaining 7 patients were hypertensive. Six patients had permanent AF and the others had recurrent paroxysmal AF (with at least 1 episode a week). Left atrial size was 40.3 +/- 6.1 mm. A total of 35 ablation procedures were performed, 12 using the focal ablation technique and 23 by PV isolation. Six patients underwent a redo procedure. Patients were evaluated at 1-year follow-up (symptoms, medication, ECG and Holter monitoring). Predictors of successful treatment were identified among baseline clinical variables (age, gender, hypertension), LA size, AF sub-type, ablation technique, and number of isolated PV, using multivariable logistic regression. RESULTS: At 1-year follow-up, 20 patients presented sinus rhythm (69%), of whom 7 were taking antiarrhythmic drugs and remained free of AF relapse. Out of the total of 35 procedures, 2 immediate complications occurred: pericardial tamponade in one patient and right phrenic nerve palsy in another. Predictors of long-term success were absence of a prior history of hypertension and isolation of at least three PV (p = 0.01 for both independent predictors). CONCLUSION: Two out of three patients who underwent AF ablation presented sinus rhythm one year after the intervention. Isolation of at least three PV and idiopathic etiology are independent predictors of successful treatment.