Follow-Up After Catheter Ablation of Papillary Muscles and Valve Cusps

Transseptal approach versus retrograde aortic approach in mapping and ablation of ventricular arrhythmias from anterolateral papillary muscles

INTRODUCTION

The anterior and lateral position of the anterolateral papillary muscle (ALPM) has found to be reached with better catheter stability and less mechanical bumping via the transseptal (TS) compared to the retrograde aortic (RA) approach. The aim of this study is to compare the TS and RA approaches on mapping and ablation of ventricular arrhythmias (VAs) arising from ALPMs.

METHODS

Thirty-two patients with ALPM-VAs undergoing mapping and ablation via the TS approach were included and compared with 31 patients via the RA approach within the same period. Acute success was compared, as well as other outcomes including misinterpreted mapping results due to bumping, radiofrequency (RF) attempts, procedural time and success rate at 12-month follow-up.

RESULTS

Acute success was achieved in more cases in the TS group (96.4% vs. 72.0%, p = .020). During activation mapping, bump-provoked premature ventricular complexes (PVCs) misinterpreted as clinical PVCs were more common in the RA group (30.0% vs. 58.3%, p = .036), leading to more RF attempts (3.5 ± 2.7 vs. 7.2 ± 6.8, p = .006). Suppression of VAs were finally achieved in the unsuccessful cases by changing to the alternative approach, but the procedural time was significantly less in the TS group (90.0 ± 33.0 vs. 113.7 ± 41.1 min, p = .027) with less need to change the approach, although follow-up success rates were similar (75.0% vs. 71.0%, p = .718).

CONCLUSION

A TS rather than RA approach as the initial approach appears to facilitate mapping and ablation of ALPM-VAs, specifically by decreasing the possibility of misleading mapping results caused by bump-provoked PVC, and increase the acute success rate thereby.

Complications of catheter ablation for ventricular tachycardia

With the increasing literature demonstrating benefits of catheter ablation for ventricular tachycardia (VT), the number of patients undergoing VT ablation has increased dramatically. As VT ablation is being performed more routinely, operators must be aware of potential complications of VT ablation. This review delves deeper into the practice of VT ablation with a focus on periprocedural complications.

Long-Term Follow-Up of Catheter Ablation for Premature Ventricular Complexes in the Modern Era: The Importance of Localization and Substrate

Background: Large-scale studies evaluating long-term recurrence rates in both idiopathic and non-idiopathic PVC catheter ablation (CA) patients have not been reported. Objective: To evaluate the efficacy and safety of idiopathic and non-idiopathic PVC CA, investigating the predictors of acute and long-term efficacy. Methods: This retrospective multicentric study included 439 patients who underwent PVC CA at three institutions from April-2015 to December-2021. Clinical success at 6 months’ follow-up, defined as a reduction of at least 80% of the pre-procedural PVC burden, was deemed the primary outcome. The secondary aims of the study were: clinical success at the last available follow-up, predictors of arrhythmic recurrences at long-term follow-up, and safety outcomes. Results: The median age was 51 years, with 24.9% patients being affected suffering from structural heart disease. The median pre-procedural PVC burden was 20.1%. PVCs originating from the RVOT were the most common index PVC observed (29.1%), followed by coronary cusp (CC) and non-outflow tract (OT) LV PVCs (23.1% and 19.0%). The primary outcome at 6 months was reached in 85.1% cases, with a significant reduction in the 24 h% PVC burden (−91.4% [−83.4; −96.7], p < 0.001); long-term efficacy was observed in 82.1% of cases at almost 3-year follow-up. The presence of underlying structural heart disease and non-OT LV region origin (aHR 1.77 [1.07−2.93], p = 0.027 and aHR = 1.96 [1.22−3.14], p = 0.005) was independently associated with recurrences. Conclusion: CA of both idiopathic and non-idiopathic PVCs showed a very good acute and long-term procedural success rate, with an overall low complication. Predictors of arrhythmic recurrence at follow-up were underlying structural heart disease and non-OT LV origin.

Aortic Regurgitation as a Complication of Electrophysiologic Ablation Techniques: A Narrative Review

BACKGROUND

Radiofrequency catheter ablation is a well-established treatment for several cardiac arrhythmias. Arrhythmias originating from the left side of the heart including ventricular and supraventricular tachycardia and ectopy can be successfully ablated through either transseptal or retrograde aortic approach. Although these techniques have a generally low rate of complications, aortic valve injury is a potential complication of ablation at the left cardiac side that warrants more investigation.

OBJECTIVE

The purpose of this review is to evaluate the incidence of iatrogenic aortic valve regurgitation and explore the potential mechanisms and risk factors that might contribute to aortic valve injury during radiofrequency ablation. Additionally, the course and progression of aortic regurgitation in the reported cases will be described.

METHODS

Authors searched PubMed for articles using the keywords "ablation" AND "aortic insufficiency" OR "aortic valve injury" OR "aortic regurgitation". Case reports and series as well as retrospective and prospective studies were included, and relevant review articles and editorial comments were used as a supplementary source of data. A total of 19 references were used and a detailed description of patient characteristics, procedural techniques, and incidence, predictors, and fate of aortic regurgitation were reported by 11 clinical studies.

RESULTS

There is a small risk of significant iatrogenic aortic regurgitation after radiofrequency ablation of left-sided cardiac arrhythmias, especially techniques performed via a retrograde aortic approach.

CONCLUSION

Although the risk is not confined to procedures applying direct energy to the aortic cusp region, a more aggressive ablation applied in the vicinity of the valvular complex seems to be associated with a higher risk. Routine post-procedural surveillance should be adopted to detect de novo aortic valve injury following radiofrequency ablation techniques.

The effect of catheter ablation for ventricular arrhythmias originating from the left ventricular papillary muscles on mitral valve function

BACKGROUND

Ablation of ventricular arrhythmias (VA) originating from the left ventricular (LV) papillary muscles (PM) has the potential to damage the mitral valve apparatus resulting in mitral regurgitation (MR). This study sought to evaluate the effect of radiofrequency (RF) ablation of a PM on MR severity.

METHODS

Patients with pre- and postablation transthoracic echocardiograms who underwent PM ablation for treatment of VA were retrospectively identified and compared to similar patients who underwent VA ablation at non-PM sites. MR severity was evaluated pre- and postablation in both groups and graded as none/trace (Grade 0); mild/mild-to-moderate (Grade 1); moderate (Grade 2); moderate-to-severe/severe (Grade 3).

RESULTS

A total of 45 and 49 patients were included in the PM and non-PM groups, respectively. There were no significant baseline demographic differences. The PM group had longer RF ablation times (22.3 vs. 13.3 min, p < .01) compared to the non-PM group. Most patients had low-grade MR in both groups at baseline. Change in pre- versus postablation MR within the PM group was not statistically significant by Wilcoxon rank-sum test (Figure 2, p = .46). MR severity following ablation was also evaluated using logistic regression models. The odds ratio for worsening MR in the PM group compared to non-PM was 0.19 (95% confidence interval: 0.008-4.18, p = .29) after adjusting for comorbidities, LV ejection fraction, and LV internal end-diastolic diameter.

CONCLUSION

RF ablation of VA originating from PM under intracardiac echocardiography guidance did not result in clinically or statistically significant worsening of MR.