T he papillary muscles (PMs) from the left ventricle (LV) have been shown to be a potential site of origin of ventricular arrhythmias (VAs) in patients with and without structural heart disease.1 Catheter ablation has been described as an effective treatment for these arrhythmias, although radiofrequency delivery at these regions has been associated with poor manipulation and catheter stability compared with other VAs. 2 See Editorial by Latchamsetty and BogunPrevious data on catheter cryoablation of PMs VAs showed high-success and low complication rates. 3 There is yet no data available comparing results of both cryoenergy and radiofrequency for catheter cryoablation of PM-related arrhythmias.This study compares procedural outcomes and recurrence rate after catheter cryoablation or radiofrequency ablation for the treatment of ventricular tachycardia (VT) and premature ventricular complexes (PVCs) localized at the PMs of the LV, with the aid of intracardiac echocardiography (ICE) and image integration. MethodsA total of 21 patients with recurrent VAs originating at the PMs of the LV were identified from retrospective review of 189 consecutive patients (men 52%, age 44 years, range 28-54 years) with symptomatic sustained VT (n=58), nonsustained VT (n=40), or PVC (n=91) referred for catheter ablation to the Buenos Aires Cardiovascular Institute (Buenos Aires, Argentina) between January 2014 and January 2016. Scar-related VT was observed in 45 patients (24%). The sites of origin of idiopathic VAs included the right ventricular (RV) outflow tract in 82 (43%), aortomitral continuity in 24 (13%), posteromedial PM (PMPM) in 19 (10%), anterolateral PM (ALPM) in 3 (1.5%), aortic root in 3 (1.5%), fascicles of the left bundle branch in 2 (1%), mitral annulus in 1 (0.5%), and other sites in 11 (6%). This study retrospectively included 21 patients with symptomatic, drug refractory, and single morphology VAs originated at the PMs of the LV. The institutional review committee approved the study and © 2016 American Heart Association, Inc. Circ Arrhythm Electrophysiol Original ArticleBackground-Catheter radiofrequency ablation of ventricular arrhythmias (VAs) arising from the left ventricle's papillary muscles has been associated with inconsistent results. The use of cryoenergy versus radiofrequency has not been compared yet. This study compares outcomes and complications of catheter ablation of VA from the papillary muscles of the left ventricle with either cryoenergy or radiofrequency. Methods and Results-Twenty-one patients (40±12 years old; 47% males; median ejection fraction 59±7.3%) with drug refractory premature ventricular contractions or ventricular tachycardia underwent catheter cryoablation or radiofrequency ablation. VAs were localized using 3-dimensional mapping, multidetector computed tomography, and intracardiac echocardiography, with arrhythmia foci being mapped at either the anterolateral papillary muscle or posteromedial papillary muscles of the left ventricle. Focal ablation was performed using an 8-mm cryoa...

An echo-facilitated 3D electroanatomical mapping allows for real-time creation of precise geometries of cardiac chambers and endocavitary structures. This is useful during procedures such as catheter ablation of VAs originating from PMs, which require detailed representation of anatomical landmarks. Routine adoption of this technique should be considered to improve outcomes of PM VA ablation.

BackgroundCatheter ablation of ventricular arrhythmias (VAs) arising from the left ventricle`s (LV) papillary muscles (PM) is challenging. In this study we present results of catheter ablation using multiple energy sources and image‐based approaches.MethodsFifty‐three patients (49 ± 17 years old; 34% females; median LV ejection fraction 53 ± 11%) underwent catheter cryoablation or radiofrequency (RF) ablation with non‐contact force sensing (Non‐CFS) catheters and cardiac computed tomography integration (CTII) into the electroanatomical mapping system or contact force sensing RF (CFS RF) ablation catheters and intracardiac echo‐facilitated 3D electroanatomical mapping. Ventricular arrhythmias foci were mapped at either the anterolateral (ALPM) or posteromedial papillary muscles (PMPM). Ablation was performed using an 8‐mm cryoablation catheter (CRYO); a Non‐CFS 4‐mm open‐irrigated RF catheter; or a CFS RF 3.5‐mm open‐irrigated tip catheter, via transmitral or transaortic approach.ResultsAcute success rate was 83% for Non‐CFS RF/CTII; 100% for CRYO/CTII (n = 16) and CFS RF/ICE3D (n = 14) (P = 0.03). Catheter stability was achieved in all patients treated with Cryo/CTII. VA recurrence at 12 months follow‐up was 48% (n = 11) for Non‐CFS RF/CTII; 19% (n = 3) for CRYO/CTII; and 7% (n = 1) for CFS RF/ICE3D (P = 0.02).ConclusionsNon‐CFS/CTII was associated with an increased risk of recurrence of the clinical arrhythmia. Ablation with either CFS RF/ICE3D or CRYO/CTII showed high acute success rates and low recurrence rates during follow‐up. Cryoablation provided stable contact and was less arrhythmogenic.

Cryoablation for arrhythmias arising from the PMs of the LV can be performed, and is a safe and effective alternative energy source for ablation.

Methods Study DesignWe conducted a longitudinal and prospective cohort study of all the consecutive patients undergoing scheduled PVI between June 2015 and May 2016 at the Instituto Cardiovascular de Buenos Aires (ICBA). Patients with paroxysmal or persistent atrial fibrillation (AF), either refractory or intolerant to antiarrhythmic therapy, and those with recurrent AF undergoing a new pulmonary vein ablation were included.The information was introduced in the database of the electrophysiology laboratory of the ICBA and was prospectively retrieved.