ORIGINAL ARTICLESCatheter Ablation For Papillary Muscle Arrhythmias A Systematic Review

Outcomes of single-procedure radiofrequency catheter ablation for idiopathic ventricular arrhythmias: a single-centre retrospective cohort study

OBJECTIVES

Radiofrequency catheter ablation is the first-line treatment for idiopathic premature ventricular complexes (PVCs) and ventricular tachycardias (VTs). However, the outcomes were less compared among the categories. The study aims to assess the effectiveness and safety of catheter ablation for idiopathic PVC/VTs in a single high-volume centre, using the right ventricular outflow tract (RVOT) as a reference.

DESIGN

Retrospective cohort study.

SETTING

Patient data were collected from a tertiary hospital in Guizhou, China.

PARTICIPANTS

Between September 2013 and September 2022, 1028 patients (male: 41.3%; age: 46.5±15.6 years) who underwent the first catheter ablation for idiopathic monomorphic PVC/VTs were enrolled.

OUTCOME MEASURES

Acute success, procedure-related complications, and long-term recurrence were assessed. Antiarrhythmic drugs (AADs) were not administrated after procedures unless recurrence was identified.

RESULTS

The overall acute success rate was 90.3%, with 368 patients (35.8%) experiencing left ventricular PVC/VTs. No cases of third-degree atrioventricular block or death were reported. Complications were more common in patients with left ventricular PVC/VTs than those with right-sided ones (4.6% vs 0.1%, p<0.001). A total of 926 patients (90.1%) were followed up for an average of 9.7±3.7 months, and only the PVC/VTs category was found to be associated with long-term success rates. The RVOT, endocardial left ventricular outflow tract (endoLVOT), tricuspid annulus (TA) free wall, posterior septum and fascicular VT had long-term success rates exceeding 85%. Other types of PVC/VTs showed significantly higher risks of recurrence.

CONCLUSIONS

Besides RVOT and fascicular VT, single-procedure catheter ablation without AADs is highly effective for endoLVOT, TA-free wall and posterior septum. Patients with left ventricular PVC/VTs have higher complication risks compared with right ones.

Feasibility and safety of reprocessing of intracardiac echocardiography catheters for electrophysiology procedures - a large single center experience

PURPOSE

Intra-cardiac echocardiography (ICE) has become an important tool for catheter ablation. Adoption of ICE imaging is still limited because of its prohibitively high cost. Our aim was to study the safety and feasibility of ICE catheters reprocessing and its environmental and financial impact.

METHODS

This was a single center retrospective analysis of all consecutive electrophysiology procedures in which ICE catheters were used from 2015 to 2022. In total, 1128 patients were studied (70.6% male, mean age was 57.9 ± 13.2 years). The majority of procedures were related to atrial fibrillation ablation (84.6%).

RESULTS

For the whole cohort, 57 new ICE catheters were used. Consequently one catheter could be used for 19.8 procedures. New catheters were only used when the image obtained by reused probes was not satisfactory. There were no cases of ICE probe steering mechanism malfunction, no procedure related infections and no allergic reactions that could be attributed to the resterilization process. In total, there was 8.6% of complications not related to ICE imaging. Financially, ICE probe reprocessing resulted with 90% cost reduction (> 2 millions of Euros savings for the studied period) and 95% waste reduction (639.5 kg less, mostly non degradable waste was produced).

CONCLUSION

Our data suggests that ICE catheter reprocessing is feasible and safe. It seems that risk of infection is not increased. Significant economic and environmental savings could be achieved by ICE catheters reprocessing. Furthermore, ICE reprocessing could allow more extensive ICE usage resulting in safer procedures with a potential reduction of serious complications.

Combination of Intracardiac Echocardiography and Contact Force Sensing for Left Ventricular Papillary Muscle Arrhythmias

OBJECTIVES

The catheter ablation of ventricular arrhythmias (VAs) arising from the left ventricular (LV) papillary muscles (PMs) is challenging. This study sought to address whether the combination of intracardiac echocardiography (ICE) and contact force sensing (CFS) can improve the acute and long-term ablation outcomes of left ventricular papillary muscle arrhythmias.

METHODS AND RESULTS

From May 2015 to August 2022, a total of thirty-three patients underwent catheter ablation for LV PM arrhythmias: VAs were located in anterolateral PMs in 11 and posteromedial PMs in 22. A combination of intracardiac echocardiography (ICE) and contact force sensing (CFS) was used in 21 of the 33 procedures. A mean of 6.93 ± 4.91 for lesions was used per patient, comparable between the CFS/ICE and no ICE/CFS (4.90 ± 2.23 vs. 10.17 ± 5.89; p = 0.011). The mean CF achieved in the ICE/CFS group was 7.52 ± 3.31 g. Less X-ray time was used in the combination group (CFS/ICE: 165.67 ± 47.80 S vs. no ICE/CFS: 365.00 ± 183.73 S; p < 0.001). An acute success rate of 100% was achieved for the ICE/CFS group (n = 22) and 66.67% for the no ICE/CFS group (n = 8). VA recurrence at the 11.21 ± 7.21-month follow-up was 14.2% for the ICE/CFS group and 50% for the no ICE/CFS group (p = 0.04). No severe complications occurred in all patients.

CONCLUSIONS

The combination of intracardiac echocardiography (ICE) and contact force sensing (CFS) could provide precise geometries of cardiac endocavitary structures and accurate contact information for the catheter during ablation, which improved acute and long-term ablation outcomes. The routine adoption of this strategy should be considered to improve the outcomes of LV PM VA ablation.

Best Practices for the Catheter Ablation of Ventricular Arrhythmias

Techniques for catheter ablation have evolved to effectively treat a range of ventricular arrhythmias. Pre-operative electrocardiographic and cardiac imaging data are very useful in understanding the arrhythmogenic substrate and can guide mapping and ablation. In this review, we focus on best practices for catheter ablation, with emphasis on tailoring ablation strategies, based on the presence or absence of structural heart disease, underlying clinical status, and hemodynamic stability of the ventricular arrhythmia. We discuss steps to make ablation safe and prevent complications, and techniques to improve the efficacy of ablation, including optimal use of electroanatomical mapping algorithms, energy delivery, intracardiac echocardiography, and selective use of mechanical circulatory support.