Comparison of safety and effectiveness of different sheaths in ablation of focal atrial tachycardia: a retrospective study.

Background: A novel visualized steerable sheath, referred to as the Vizigo sheath, has been utilized in clinical interventions. The objective of this study was to evaluate and contrast the efficacy and safety of the Vizigo sheath with other sheaths in the catheter ablation (CA) for focal atrial tachycardia (FAT). Methods: A retrospective cohort study was conducted on consecutive patients with CA for FAT from March 2019 to February 2022. Objectives were to assess the impact of the Vizigo sheath on acute and long-term ablation success rates, procedural and fluoroscopy times, and contact force (CF). Results: A total of 164 patients, mean age 50±15 years, 97 (59.1%) women, underwent CA of FAT using the Vizigo sheath (N=42), non-visualized steerable sheath (N=36), or other conventional sheath (N=86). Age, sex, body mass index (BMI), presence of hypertension, heart failure, and diabetes mellitus were not significantly different among the three groups. The acute success rate of 94.0% was similar among the three groups. Over a follow-up of 14±2 months, the Vizigo sheath was associated with superior arrhythmia-free survival (88.1%) when compared to non-visualized steerable (69.4%; P=0.04) and other conventional (72.1%, P=0.046) sheaths. Procedural duration, number of ablation lesions, and ablation times were similar among the three groups. However, the Vizigo sheath was associated with lower fluoroscopy times (e.g., 145 vs. 250 s with Vizigo versus non-visualized steerable sheaths, P=0.03) and higher CF (e.g., average CF 12.0 versus 8.0 g with Vizigo versus non-visualized steerable sheaths, P=0.003). Conclusions: The application of Vizigo sheath can improve the long-term success rate of FAT and reduce the radiation exposure of patients and medical staff in our single-center limited sample study. More research may be needed in the future to confirm our findings.

Association of left atrial wall thickness with recurrence after cryoballoon ablation of paroxysmal atrial fibrillation.

BACKGROUND: Transmural injury plays a role in successful atrial fibrillation ablation. The effect of left atrial wall thickness (LAWT) on the efficacy of radiofrequency ablation has been identified, but data on the relationship between LAWT and cryoballoon for paroxysmal atrial fibrillation (PAF) are lacking. We aim to explore the relationship between LAWT and recurrence after cryoballoon ablation (CBA). METHODS: We studied 364 patients (mean age 62 years) with PAF who underwent a second-generation CBA and pre-procedure cardiac CTA. LAWT and left atrial volume index (LAVI) were obtained based on pre-procedure cardiac CTA measurements. Follow-up was at least 12 months and predictors of atrial tachyarrhythmia recurrence during follow-up were assessed. RESULTS: Patients were followed up for a median of 19 (12-28) months, with an atrial tachyarrhythmia-free rate of 77.5% after cryoablation. Greater LAVI (50.0 ± 19.6 mL/m2 vs. 44.3 ± 15.4 mL/m2, P = 0.018) and greater LAWT (1.67 ± 0.24 vs. 1.46 ± 0.25 mm, P < 0.001) were associated with atrial tachyarrhythmia recurrence. The mean LAWT of PV antrum correlated with TTI (R = 0.252, P < 0.001). Adding LAWT to the established risk model improved both the discrimination and reclassification effects (IDI: 0.099, 95% CI: 0.065-0.134, P < 0.001; NRI: 0.685, 95% CI: 0.455-0.915, P < 0.001). In a multivariable Cox proportional hazard model, the mean LAWT of PV antrum (hazard ratio [HR]:3.657, 95%CI: 2.319-5.765, P < 0.001) was an independent predictor of atrial tachyarrhythmia recurrence after cryoablation. CONCLUSIONS: The mean LAWT of PV antrum, obtained from preoperative measurements on CT, was associated with atrial tachyarrhythmia recurrence after cryoablation.

Early rhythm control vs. rate control in atrial fibrillation: A systematic review and meta-analysis.

Objective: It has long been debated whether rhythm control vs. rate control strategies have differing effects on mortality and morbidity for atrial fibrillation (AF). Recently, several randomized controlled studies (RCTs) and observational trials described that an early rhythm management method was linked to a lower likelihood of negative clinical outcomes in individuals with AF. We wanted to see if an early rhythm management method may help patients with AF. Methods: We performed a systematic search to retrieve studies assessing the outcomes of early rhythm control vs. rate control in AF by using PubMed, Web of Science, Cochrane Library, and Embase published between 01/01/2000 and 15/04/2022. Results: Finally, two RCTs, one retrospective analysis of RCTs, and four observational studies were identified. Compared with rate control, early rhythm control has been linked to lower all-cause mortality. [risk ratio (RR), 0.76; 95% CI 0.69-0.83; P < 0.00001; I 2 = 77%]. The early rhythm control group was also associated with a lower risk of cardiovascular mortality (RR, 0.68; 95% CI 0.63-0.74; P < 0.00001; I 2 = 33), stroke (RR, 0.77; 95% CI 0.67-0.87; P < 0.001; I 2 = 64), and heart failure hospitalization (RR, 0.74; 95% CI 0.59-0.93; P = 0.0009; I 2 = 93%). We found no significant difference in nights spent in hospital per year, acute coronary syndrome, major bleeding, and cardiac arrest/ventricular arrhythmia between the groups. Conclusion: In this meta-analysis, early rhythm therapy was linked to a lower risk of all-cause mortality, cardiovascular mortality, stroke, and heart failure hospitalization compared with the rate control group. Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42022333592.

Left Atrial Appendage Closure for Atrial Fibrillation in the Elderly >75 Years Old: A Meta-Analysis of Observational Studies

Background: Left atrial appendage closure (LAAC) is an established therapy for patients with atrial fibrillation (AF); however, there is a limited understanding of LAAC in elderly patients (≥75 years old). We conducted a meta-analysis to investigate the procedural complications and long-term outcomes after LAAC in the elderly versus the non-elderly. Methods: We screened PubMed, EMBASE, Cochrane Library, and Web of Science. Procedural endpoints of interest included successful implantation LAAC rates, in-hospital mortality, major bleeding events, pericardial effusion/tamponade, stroke, and vascular access complications related to LAAC. Long-term outcomes included all-cause mortality, major bleeding events, and stroke/transient ischemic attack (TIA) during follow-up. Results: Finally, 12 studies were included in the analysis; these included a total of 25,094 people in the elderly group and 36,035 people in the non-elderly group. The successful implantation LAAC rates did not differ between the groups, while the elderly patients experienced more periprocedural mortality (OR 2.62; 95% CI 1.79−3.83, p < 0.01; I2 = 0%), pericardial effusion/tamponade (OR 1.39; 95% CI: 1.06−1.82, p < 0.01; I2 = 0%), major bleeding events (OR 1.32; 95% CI 1.17−1.48, p < 0.01; I2 = 0%), and vascular access complications (OR 1.34; 95% CI 1.16−1.55, p < 0.01; I2 = 0%) than the non-elderly patients. The long-term stroke/TIA rates did not differ between the elderly and the non-elderly at least one year after follow-up. Conclusions: Even though successful implantation LAAC rates are similar, elderly patients have a significantly higher incidence of periprocedural mortality, major bleeding events, vascular access complications, and pericardial effusion/tamponade after LAAC than non-elderly patients. The stroke/TIA rates did not differ between both groups after at least one-year follow-up.

Left atrial appendage function and structure predictors of recurrent atrial fibrillation after catheter ablation: A meta-analysis of observational studies.

Background: The results of studies evaluating the left atrial appendage (LAA) function and structure as predictors of atrial fibrillation (AF) recurrence after catheter ablation (CA) are contradictory. Therefore, we performed a meta-analysis to assess whether the LAA function and structure can predict the recurrence of AF after CA. Methods: The PubMed, EMBASE, Web of Science, and Cochrane library databases were used to conduct a comprehensive literature search. Finally, 37 studies encompassing 11 LAA parameters were included in this meta-analysis. Results: Compared with those in the non-recurrence group, the recurrence group had increased LAA volume (SMD 0.53, 95% CI [0.36, 0.71] p < 0.00001), LAA volume index, LAA orifice area, and LAA orifice short/long axis and decreased LAA emptying flow velocity (SMD -0.54, 95% CI [-0.68, -0.40], P < 0.00001), LAA filling flow velocity, and LAA ejection fraction, while there was no significant difference in LAA morphology or LAA depth. Conclusion: Large LAA structure of pre-ablation (LAA volume, orifice area, orifice long/short axis, and volume index) and decreased LAA function of pre-ablation (LAA emptying flow velocity, filling flow velocity, ejection fraction, and LASEC) increase the odds of AF recurrence after CA. Systematic review registration: [https://www.crd.york.ac.uk/prospero/], identifier [CRD42022324533].

Effects of the visualized steerable sheath applied to catheter ablation of paroxysmal atrial fibrillation.

PURPOSE: A new type of visualized steerable sheath (Vizigo sheath; Biosense Webster Inc., Irvine, CA, USA) has been employed in clinical treatment. This study aimed to compare the effectiveness and safety of the Vizigo sheath to a fixed sheath (Swartz sheath; St. Jude Inc., St. Paul, MN, USA) for catheter ablation of paroxysmal atrial fibrillation (PAF). METHODS: We analyzed the procedural time, fluoroscopy time, contact force (CF), and initial pulmonary vein isolation (PVI) rate. After 6 months of follow-up, the success rate of ablation between the two groups was compared. RESULTS: Compared to the Swartz sheath, using the Vizigo sheath can significantly reduce the total procedural time and fluoroscopy time and increase the overall average CF, especially in the anterior left pulmonary vein (LPV), superior LPV, posterior right pulmonary vein (RPV), and superior RPV. The proportion of CF within a reasonable range in the Vizigo group was significantly higher than that in the Swartz group, especially in the anterior LPV, posterior RPV, and superior RPV. Besides, the left, right, and bilateral initial PVI rates in the Vizigo group were significantly higher. CONCLUSIONS: The visualized steerable sheath for PAF catheter ablation not only reduced radiation exposure but also significantly improved CF and initial PVI rate, all of which indicated an increased rate of successful ablation.

The impact of exercise training for chronic heart failure patients with cardiac resynchronization therapy: A systematic review and meta-analysis.

BACKGROUND AND OBJECTIVE: Systematically review the current published literature on the impact of exercise training (ET) in chronic heart failure (CHF) patients who were conducted cardiac resynchronization therapy (CRT). METHODS: PubMed, EMBASE, and the Cochrane Library of Controlled Trails databases were searched for trials comparing the additional effects of ET in CHF patients after CRT implantation with no exercise or usual care control up until 2020.03.07. We independently screened the literature, extracted data, employed the tool for the assEssment of Study qualiTy and reporting in EXercise (TESTEX) to evaluate study quality and risk of bias, and performed meta-analysis with Revman 5.3 software. RESULTS: Eight trials were identified for qualitative analysis and 7 randomized controlled trails (RCTs) included 235 participants (120 ET; 115 controls) for quantitative analysis. The results showed that the maximal workload (mean difference [MD] 26.32 W, 95% CI 19.41-33.23; P < .00001, I2 = 0%) and the exercise duration (MD 68.95 seconds, 95% CI 15.41-122.48; P = .01, I2 = 76%) had significant improvement in the ET group versus control. Subgroup analysis showed that compared with control, the change in peak oxygen uptake (VO2) (MD 3.05 ml/kg/minute, 95% CI 2.53-3.56; P < .00001, I2 = 0%), left ventricular ejection fraction (LVEF) (MD 4.97%, 95% CI 1.44-8.49; P = .006, I2 = 59%), and health related quality of life (HRQoL) (the change in Minnesota living with heart failure questionnaire [MLHFQ]: MD -19.96, 95% CI -21.57 to -18.34; P < .00001, I2 = 0%) were significantly improved in the light to moderate intensity training (non-HIT) group, while there seemed no statistical difference of above endpoints in the high intensity training (HIT) group. CONCLUSION: During the short term (up to 6 months), non-HIT could improve exercise capacity, cardiac function, and HRQoL in CHF patients with CRT. However, due to the small number of participants, a high-quality large-sample multicenter trial is demanded.

Electrophysiological study and radiofrequency ablation of hemodynamically-instable ventricular arrhythmias in a patient with pulmonary hypertension: A case report.

INTRODUCTION: Hemodynamically-instable ventricular arrhythmias (VAs) are rare in patients with pulmonary hypertension (PH). To the best of our knowledge, only 1 case has been reported so far. Moreover, the pathogenesis of this kind of arrhythmia remains obscured and its treatment is challenging. Here we report another case and presented the substrate for VAs initiation and therapeutic effect of radiofrequency ablation. PATIENT CONCERNS: This is a 57-year-old man who presented paroxysmal palpitation associated with presyncope at rest. Surface electrocardiogram (ECG) revealed frequent ventricular premature contractions and non-sustained ventricular tachycardia when symptoms occurred. He also had a history of severe PH which was secondary to atrial septal defect and partial anomalous pulmonary venous drainage and suffered from obvious dyspnea when climbing stairs World Health Organization Class III (WHO Class III). DIAGNOSIS: Hemodynamically-instable VAs associated with severe PH. INTERVENTION: Echocardiography revealed enlargement of right ventricle (right ventricle [RV]: 43 mm). Electrophysiological examination showed the origin of VAs is next to a small low-voltage zone of RV. Radiofrequency delivery at the origin successfully terminated VAs without occurrence of complication. OUTCOME: The patient was free from arrhythmias and got an improvement of exercise tolerance, just with mild dyspnea when climbing stairs World Health Organization Class II (WHO class II), during six-month follow up. LESSONS: This case suggests the low-voltage zone of remodeled RV, which may be secondary to increased pulmonary artery pressure, serves as the substrate for VAs initiation in patient with PH. Radiofrequency ablation can successfully terminate VAs and the termination of VAs can significantly improve the patient's impaired exercise tolerance.

The ratio of main pulmonary artery to ascending aorta diameter is associated with the right ventricular outflow tract ventriculararrhythmias.

BACKGROUND: Although outflow tract (OT) ventricular arrhythmias (VAs) are generally regarded as benign, the relationship between circulation pressure and VAs has received considerable attention in recent years. Previous studies have shown that the ratio of main pulmonary artery (MPA) to ascending aorta (AA) diameter is associated with pulmonary pressure. Here, we investigated whether an elevated MPA/AA ratio is associated with right ventricular OT (RVOT) VAs. METHODS: A total of 67 patients with OT VAs (47 patients with RVOT and 20 patients with LVOT) who underwent cardiac multidetector computed tomography and radiofrequency ablation were enrolled in this study. MPA and AA diameters were measured at the level of the bifurcation of the pulmonary artery. According to the MPA/AA ratio, patients were further divided into two groups: the MPA/AA ratio abnormal group (n = 19), which is defined as MPA/AA ratio ≥ 0.9, and the MPA/AA ratio normal group (n = 48) consisting of patients with an MPA/AA ratio < 0.9. RESULTS: Patients with RVOT VAs exhibited an elevated MPA/AA ratio (0.84 ± 0.11 vs. 0.75 ± 0.11, p = 0.006). Furthermore, this MPA/AA ratio was shown to be an independent predictor for RVOT VAs (p = 0.013, 95% confidence interval: 1.016-1.145), with an abnormal MPA/AA ratio increasing the odds of RVOT VAs 5.1-fold in patients with OT VAs. CONCLUSION: Patients with RVOT VAs exhibited significantly higher MPA/AA ratios compared with those LVOT VAs. The MPA/AA ratio was showed to be an independent predictor RVOT VAs.

Merging three-dimensional CT with electroanatomic mapping facilitates ablation of ventricular arrhythmias originating from aortic root and great cardiac vein.

PURPOSE: In radiofrequency ablation near coronary arteries (CA), coronary angiography is traditionally recommended to estimate distance between catheter and CA. This study aimed to investigate the feasibility of an alternative approach for intuitively demonstrating spatial location of catheter and CA during ablation of ventricular arrhythmias (VAs) originating from aortic root (AR) and great cardiac vein (GCV). METHODS: During mapping and ablation, 3D-reconstructed cardiac CT and electroanatomic mapping were merged, and distance between CA and catheter was monitored. Coronary angiography, for distance verification, was used when the distance was less than 5 mm in image integration model (IIM). RESULTS: Twenty-three patients (52.26 ± 17.89 years, 12 men) with ablation originating in left cusp (LCC, n = 8), right cusp (n = 2), and left-right cusp junction (LCC-RCC, n = 12) and GCV (n = 1) were enrolled. In IIM, the distance between origin and CA was less than 5 mm in 2 VAs originating in LCC and one in GCV (3/23), whereas distance for ablation was always safe (12.3-22.3 mm) for VAs of LCC-RCC origin. IIM avoided angiography use in 20 patients, reducing radiation exposure by 80.6% (650.18 ± 624.31 vs 3356.97 ± 1529.46uGycm2, P = 0.088). VA termination failed in two cases of LCC origin due to proximity to CA, and was achieved in all other patients (91.3%). No CA damage occurred during the procedures. CONCLUSION: Mapping and ablation under IIM guidance of VAs of AR and GCV origin appears feasible and safe, while avoiding angiography use particularly in VAs of LCC-RCC origin.