Predictors of long-term success after catheter ablation of premature ventricular complexes

Single catheter approach for treatment of premature ventricular contractions

BACKGROUND

Catheter ablation has become one of the main treatment strategies in patients with premature ventricular complexes (PVC). The successful mapping and ablation can be performed with an ablation catheter without additional diagnostic catheters.

HYPOTHESIS

We hypothesize that using a single catheter for PVC ablation may decrease complications, procedure time, and fluoroscopy exposure while maintaining comparable success rates.

METHODS

Sixty-nine consecutive patients with PVC were treated with a single catheter approach compared to a historical cohort, in which a conventional setup was used. Propensity score matching was conducted with a 1:1 ratio. Outcome parameters included acute procedural success with elimination of all premature ventricular contractions after catheter ablation, procedural data as well as complication rates.

RESULTS

Patients treated with a single catheter approach had shorter total procedure (60 minutes [IQR: 47,5-69,0 minutes] vs. 90 minutes [IQR 60-120 minutes]; p = 0.001) and fluoroscopy times (218 seconds [IQR: 110,5-446 seconds] vs. 310 seconds [IQR 190-640 seconds]; p = 0.012), which consecutively leads to a reduction of radiation exposure signified by a lower dose area product (155 cGycm² [IQR 74.4-334.5 cGycm²] vs. 368.4 cGycm² [IQR: 126-905.4 cGycm²]; p value 0.009). Acute procedural success rates were comparable in both groups (54 [84.3%] in the single catheter approach group and 58 [90.6%] in the conventional group; p: 0.287).

CONCLUSION

A single catheter approach for the treatment of PVC is associated with a reduction of procedure- and fluoroscopy time, as well as a lesser radiation exposure, while maintaining equivalent acute success and complication rates compared with a conventionally used catheter setup.

Successful radiofrequency catheter ablation of idiopathic premature ventricular complexes originating from the outflow tract improves heart failure-related quality of life

BACKGROUND

To investigate the effect of successful RFCA in patients with idiopathic outflow tract PVCs (OT-PVC) on left heart functions, neurohormonal activation, functional status, and heart failure-related quality of life (HFQoL), with an integrated approach.

METHODS

Patients with frequent OT-PVCs, determined by 12-lead surface ECG who underwent radiofrequency catheter ablation (RFCA) with an acute success, were prospectivelly enrolled. Left heart functions were evaluated with the use of transthoracic echocardiography, neurohormonal activation with N-terminal Pro-brain natriuretic peptide (BNP), functional class with New York Heart Association (NYHA) and 6-min walking distance (6MWD), and HFQoL with Minnesota Living with Heart Failure Questionnaire (MLHFQ), at baseline and at 6 months.

RESULTS

A total of 108 patients were included in this study (43 ± 12 years old, 56% male). Majority of the OT-PVCs originated from aortic valve and right ventricle outflow tract (44% and 37%, respectively). Total RF time was 216 ± 87 s. Major complication rate was 0.9%. Left ventricle (LV) ejection fraction increased from 47 ± 8 to 53 ± 6% at 6 months (p < 0.001). Neurohormonal activation was suppressed significantly (104 ± 69 to 83 ± 42, p < 0.001). Functional class improved with %NYHA-I patients increasing from 54 to 89% (p < 0.001) and 6MWD from 293 ± 73 to 335 ± 59 m (p < 0.001). MLHFQ score improved from 32 ± 9 to 23 ± 5 p < 0.001. In multivariable analysis, LV end-systolic diameter (LVESD) and 6MWD were independent predictors of improvement in MLHFQ (for LVESD Uβ: - 0.26, 95%CI [0.44-0.09], p < 0.004 and for 6MWD: 0.04, 95%CI [0.03-0.06], p < 0.001).

CONCLUSIONS

RFCA of OT-PVCs is associated with improved well-being of patients, determined by left heart functions, neurohormonal activation, functional class, and HFQoL.

Acupuncture for premature ventricular complexes without ischemic or structural heart diseases: A systematic review and meta-analysis of clinical and pre-clinical evidence

Background

With increasing evidence suggesting potential benefits, acupuncture is often applied to the treatment of premature ventricular complexes (PVCs), particularly in symptomatic patients who fail or are unsuitable for medications or refuse catheter ablation. However, the existing clinical evidence is inconsistent.

Objectives

This review aims to systematically evaluate the effectiveness and safety of acupuncture therapies for PVCs without ischemic or structural heart diseases, when it is compared with sham/placebo acupuncture or usual care, or used as an add-on therapy to routine care; and to summarize existing pre-clinical research evidence supporting the effects of acupuncture therapies for this clinical condition.

Methods

Four English-language databases, four Chinese-language databases and seven clinical registries were searched from their inceptions to May 21, 2021 and updated to November 01, 2022. Trials comparing acupuncture with sham acupuncture or evaluating the add-on effects of acupuncture were included. Primary outcomes are the number of premature ventricular beats (PVBs) and effective rate defined as "the proportion of participants with over 50% decrease in the number of PVBs from baseline to the end of treatment measured by 24-h Holter".

Results

A total of 479 records were identified with nine trials involving 847 participants included in this review. Meta-analysis on two sham-control trials with low risk of bias for all domains suggested that acupuncture could significantly reduce the number of PVBs (RR 3.83, 95% CI [2.19, 6.7], I ² = 0%). Moreover, the combination of acupuncture and standard treatment was superior to standard treatment alone in reducing the burden of PVBs (RR 1.21, 95% CI [1.08, 1.36], I ² = 0%). Though no treatment protocol consensus was announced, body acupuncture on point PC6, HT7, DU10, DU11, and ST36 with duration of needle retention ranging from 15 to 30 min for a 4-week treatment period is broadly used by the included trials. For experimental evidence, five studies explored the mechanisms of acupuncture for PVCs were eventually included into analysis and PC6 was the most frequently studied acupuncture point. Moreover, a reduction of electrical activity of sympathetic nerves in experimental animals undergoing electro-acupuncture was observed by four of these studies.

Conclusion

Sham-controlled RCT evidence with moderate-level certainty suggested that acupuncture could be a therapeutic option to reduce the burden of PVBs in patients without ischemic or structural heart diseases. Further clinical studies using validated and reliable outcome measurement instruments and bench research to unveil the mechanisms of acupuncture stimulation and point-specific effects for PVCs are needed.

Systematic review registration

[https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=262132], identifier [CRD42021262132].

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.

Substrate Characterization and Outcomes of Catheter Ablation of Ventricular Arrhythmias in Patients With Mitral Annular Disjunction

BACKGROUND

Mitral annular disjunction (MAD) has recently been recognized as an arrhythmogenic entity. Data on the electrophysiological substrate as well as the outcomes of catheter ablation of ventricular arrhythmias in patients with MAD is limited.

METHODS

Forty patients with MAD (mean age 47±15 years; 70% female) underwent catheter ablation for ventricular arrhythmias. Detailed clinical, electrocardiographic, cardiac imaging, and procedural data were collected. Clinical outcomes were compared between patients who had substrate modification in the MAD area and those who did not.

RESULTS

Twenty-three (57.5%) patients had ablation for premature ventricular contractions, 10 (25%) patients for sustained ventricular tachycardia, and 7 (17.5%) patients for premature ventricular contraction-triggered ventricular fibrillation ablation. Mean end-systolic MAD length was 10.58±3.49 mm on transthoracic echocardiography. Seventeen (42.5%) patients had preprocedural cardiac magnetic resonance imaging, and 5 (29%) patients had late gadolinium enhancement. Among the 18 (45%) patients who had abnormal local electrograms (low voltage, long-duration, fractionated, isolated mid-diastolic potentials) during electroanatomical mapping, 10 (25%) patients had abnormal electrograms in the anterolateral mitral annulus or MAD area. Substrate modification was performed in 10 (25%) patients. Catheter ablation was acutely successful in 36 (90%) patients (elimination of premature ventricular contraction or noninducibility of ventricular tachycardia). After a median follow-up duration of 54.08 (interquartile range, 10.67-89.79) months, premature ventricular contraction burden decreased from a median of 9.75% (interquartile range, 3.25-14) before the ablation to a median of 4% (interquartile range, 1-7.75) after the ablation (P=0.03 [95% CI, 0.055-6.5]). Eight (20.5%) patients had repeat ablation for ventricular arrhythmias. Substrate modification of the MAD was associated with a trend toward lower rates of repeat ablation (0% versus 26.7%; P=0.16).

CONCLUSIONS

Patients with MAD have a complex arrhythmogenic substrate, and catheter ablation is effective in reducing recurrence of ventricular arrhythmias. Substrate mapping and ablation may be considered in these patients.

Contemporary Management of Complex Ventricular Arrhythmias

Percutaneous catheter ablation is an effective and safe therapy that can eliminate ventricular tachycardia, reducing the risks of both recurrent arrhythmia and shock therapies from a defibrillator. Successful ablation requires accurate identification of arrhythmic substrate and the effective delivery of energy to the targeted tissue. A thorough pre-procedural assessment is needed before considered 3D electroanatomical mapping can be performed. In contemporary practice, this must combine traditional electrophysiological techniques, such as activation and entrainment mapping, with more novel physiological mapping techniques for which there is an ever-increasing evidence base. Novel techniques to maximise energy delivery to the tissue must also be considered and balanced against their associated risks of complication. This review provides a comprehensive appraisal of contemporary practice and the evidence base that supports recent developments in mapping and ablation, while also considering potential future developments in the field.

Rationale and study design for empirical additional lesions for premature ventricular complex from the outflow tract: a multi-center, prospective randomized trial (EASE-PVC study)

BACKGROUND

Late recurrence after ablation remains a significant issue in patients with premature ventricular complexes (PVCs) who undergo catheter ablation. In this study, we aimed to test the hypothesis that empirical additional ablation (EAA) would improve the long-term control of PVCs from outflow tracts (OT-PVCs) compared with the approach of limited single point ablation at the assumptive location.

METHODS

EASE-PVC study (ChiCTR2200055340) is a prospective multi-center, randomized, and controlled trial designed to assess the effectiveness and safety of empirical additional ablation in patients with OT-PVCs. After successful elimination of OT-PVCs, the patients will be randomized into two groups. In patients randomized to the EAA group, additional lesion applications at sites surrounding the successful ablation site will be delivered empirically. For patients randomized to the control group, no additional empiric ablation will be performed around the successful ablation site. The primary endpoint will be freedom from PVC recurrence at 3 months following ablation, without antiarrhythmic drug therapy.

CONCLUSIONS

The EASE-PVC study is designed to compare the effectiveness and safety of two different strategies for ablation in patients with OT-PVCs, namely empirical additional ablation strategy versus conventional single point ablation strategy. This prospective, multi-center, and randomized controlled trial, with comparative data evaluating procedural and long-term follow-up results, aims to elucidate the superiority of empirical additional ablation for the long-term control of OT-PVCs compared with the traditional single point ablation strategy.

CLINICAL TRIAL REGISTRATION

Chinese Clinical Trials Registry Identifier: ChiCTR2200055340.

Radiofrequency ablation reduces expression of SELF by upregulating the expression of microRNA-26a/b in the treatment of atrial fibrillation

BACKGROUND

In this study, we aimed to investigate the role of miR-26a and miR-26b in the management of AF.

METHODS

Real-time PCR was carried out to determine plasma microRNA expression in AF patients pre- and post-radiofrequency ablation. The correlation between the expression of SELP and miR-26a/miR-26b was also studied using luciferase assays to establish a miR-26a/miR-26b/SELP signaling pathway.

RESULTS

The relative expression of SELP reached its peak in pre-ablation AF ( +) patients, while ablation treatment reduced the expression of SELP in AF ( +) patients. Similarly, AF pigs showed dysregulation of miR-26a/b and SELP, thus verifying the involvement of miR-26a/b and SELP in AF. Meanwhile, the regulatory association between SELP and miR-26a/b was also investigated, and the results showed that the presence of pre-miR-26a/b increased the levels of miR-26a/b and inhibited the mRNA/protein expression of SELP. Finally, using bioinformatic tools and luciferase assays, SELP mRNA was confirmed as the target of miR-26a/b, which affected the effect of AF ablation treatment.

CONCLUSIONS

RFA helped to restore circulating levels of miR-26, which were reduced in atrial fibrillation. Meanwhile, miR-26 is a potential cause for the elevated plasma levels of pro-thrombogenic SELP in that disease.