CArdiac MagnEtic resonance assessment of bi-Atrial fibrosis in secundum atrial septal defects patients: CAMERA-ASD study

Relationships between biatrial substrate and recurrence after radiofrequency ablation in patients with persistent atrial fibrillation

BACKGROUND

Global longitudinal strain (GLS) and atrial voltage are acknowledged markers for worse rhythm outcome after ablation of persistent atrial fibrillation (PeAF). The majority of research efforts have been directed towards the left atrium (LA), with relatively fewer studies focusing on the right atrium (RA). The aim of this study was to investigate the effect of the biatrial substrate on the outcome following radiofrequency catheter ablation (RFCA).

METHODS

All patients underwent two-dimensional speckle tracking echocardiography (2D-STE) and high-density mapping (HDM) on LA and RA in preoperative and postoperative stages of RFCA. Atrial substrate was assessed by GLS, average voltage, and low voltage zone (LVZ).

RESULTS

This retrospective study enrolled 48 patients. With a follow-up of 385.98 ± 161.78 days, 22.92% (11/48) of all patients had AF recurrence and 63.64% in low strain group. Left atrial-low voltage zone (LA-LVZ) prior to RFCA was 67.52 ± 15.27% and 54.21 ± 20.07%, respectively, in the recurrence group and non-recurrence group. Multivariate regression analysis showed that preoperative LA-GLS (OR 0.047, 95%CI 0.002-0.941, p = .046) was independent predictors of AF recurrence. Biatrial average voltage in preoperative and postoperative stages were positively correlated (preoperative: r = 0.563 p < .001; postoperative: r = 0.464 p = .002). There was no significant difference in the proportion of RA in the recurrence group except the septum in preoperative and postoperative stages.

CONCLUSIONS

Low LA-GLS and high LA-LVZ may be predictors of RFCA recurrence in PeAF patients. Biatrial average voltage were positively correlated in preoperative and postoperative stages.

Correlation between Epsilon Wave and Late Potentials in Arrhythmogenic Right Ventricular Cardiomyopathy-Do Late Potentials Define the Epsilon Wave?

Introduction: Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a genetic disorder characterised by progressive fibrosis predominantly of the right ventricular (RV) myocardium, resulting in life-threatening arrhythmias and heart failure. The diagnosis is challenging due to a wide spectrum of clinical symptoms. The important role of ECG was covered in the current diagnostic criteria. The role of the epsilon wave (EW) is still under discussion. Aim: The aim of the study was to examine a potential association between the EW and late ventricular potentials (LPs) in ARVC patients (pts). The correlation between RV dilatation or dysfunction and LPs/EW was also analysed. Methods: The ARVC group consisted of 81 pts (53 men, aged 20-78 years) fulfilling 2010 International Task Force Criteria. 12-lead ECG, LPs, Holter, and ECHO were performed in all pts. The presence of EW was analysed in ECG by 3 investigators. LPs were detected by signal-averaged ECG (SAECG). SAECG was considered positive for LPs when at least two of the three following criteria were met: (1) the filtered QRS duration (fQRS) ≥ 114 msec; (2) the duration of the final QRS fragment in which low-amplitude signals lower than 40 μV are recorded (LAS-40 > 38 msec); and (3) the root mean square amplitude of the last 40 milliseconds of the fQRS complex (RMS-40 < 20 μV). The results were compared with a reference group consisting of 53 patients with RV damage in the course of atrial septum defect (ASD) or Ebstein's Anomaly (EA). Results: In the ARVC group, a significant relationship was observed between the occurrence of EW and the presence of LPs. EW was more common in the LP+ than in the LP- patients (48.1% vs. 6.9%, p < 0001; OR 12.5; 95% CI [2.691-58.063]). In ARVC pts, RVOT > 36 mm, RVIT > 41 mm, and RV S' < 9 cm/s were observed significantly more often in the LPs+ than in the LPs- group (OR [95% CI]: 8.3 [2.9-1.5], 6.4 [2.2-19.0] and 3.6 [1.1-12.2], respectively). In the ARVC group, any of fQRS > 114 ms, LAS > 38 ms, and RMS < 20 μV were significantly more frequent in EW+ pts. In multivariate analysis, the independent factors of the EW were LAS-40 and RV S'. In the LPs- subgroup, RVOT > 36 mm was more frequent in ASD/EA than in ARVC (70.4% vs. 25%, p = 0.002). Similarly, in the LPs- subgroup, RVIT > 41 mm was encountered more frequently in ASD/EA than in ARVC (85.2% vs. 48.3%, p = 0.004). Conclusions: In ARVC, there is an association between EW and LPs, with both probably resulting from the same process of fibrofatty substitution of the RV myocardium. Although RV dilatation is common in ASD and EA, it does not correlate with LPs.

Electrocardiographic Characteristics in 438 Neonates with Atrial Septal Defects

Arrhythmias and electrocardiographic (ECG) abnormalities are common among patients with atrial septal defects (ASDs). We studied a large cohort of neonates with ASDs to investigate whether ECG abnormalities are present at this early stage or develop later, secondary to hemodynamic changes. We analyzed the echocardiograms and ECGs from the Copenhagen Baby Heart Study, a population-based cohort study. We compared ECG characteristics of 438 neonates with secundum ASDs to 1314 matched controls. In subgroup analyses, we investigated whether electrocardiographic characteristics were associated with age at examination. Neonates with ASDs (median age, 11 days; males, 51%) had longer P-wave durations (58 vs. 56 ms, p < 0.001), PR intervals (100 vs. 96 ms, p < 0.001), and a more rightward-shifted QRS axis (116 vs. 114 degrees, p = 0.032) compared to controls (median age, 10 days; males, 51%). There were no differences between cases and controls in the P-wave area, amplitude, or axis. Subgroup analyses showed that the differences in P-wave duration and PR interval were present in neonates examined in the first week after birth. The difference in the QRS axis was not found in neonates examined this early but was found in neonates examined at age two to four weeks. In conclusion, ASDs are associated with ECG changes from the neonatal phase. The P-wave duration and PR interval are longer in neonates with ASDs when compared to controls as early as the first week after birth, indicating that these changes are not purely secondary, but that neonates with an ASD have altered cardiac electrical activity.ClinicalTrials.gov Identifier NCT02753348 (April 27, 2016).

Arrhythmic Risk and Treatment after Transcatheter Atrial Septal Defect Closure

Atrial septal defect (ASD) represents the most common congenital heart defect identified in adulthood. Atrial and ventricular geometric remodeling due to intracardiac shunt increase the risk of arrhythmias, especially atrial fibrillation (AF). Clinical, echocardiography, electrocardiogram, and device-related predictors may be used to assess the risk of atrial arrhythmias after ASD closure. The underlying mechanisms in these patients are complex and at least in part independent of the structural remodeling secondary to hemodynamic overload. Device closure of the ASD itself and its timing impact future arrhythmia risk, as well as posing a challenge for when transseptal puncture is required. Sudden cardiac death (SCD) risk is higher than in the general population and an implantable cardioverter-defibrillator (ICD) may be indicated in selected cases.

Right atrial dysfunction is associated with atrial arrhythmias in adults with repaired tetralogy of fallot

BACKGROUND

Adults with repaired tetralogy of Fallot (TOF) have right atrial (RA) remodeling and dysfunction, and RA function can be measured using speckle tracking echocardiography. There are limited data about the role of RA strain imaging for risk stratification in this population. We hypothesized that RA reservoir strain can identify TOF patients at risk of developing atrial arrhythmia. To test this hypothesis, we assessed the relationship between RA reservoir strain and atrial arrhythmias in adults with repaired TOF.

METHOD

Retrospective cohort study of adults with repaired TOF, and no prior history of atrial arrhythmias. Atrial arrhythmia was defined as atrial fibrillation, atrial flutter/atrial tachycardia, and categorized as new-onset versus recurrent atrial arrhythmias.

RESULTS

We identified 426 patients (age 33 ± 12 years; males 208 (49%)) that met the inclusion criteria. The mean RA reservoir strain, conduit strain, and booster strain were 34 ± 11%, 20 ± 9%, and 15 ± 12%, respectively. Of 426 patients, 73 (17%) developed new-onset atrial arrhythmias (atrial flutter/tachycardia n = 42; atrial fibrillation n = 31); annual incidence 1.9%. RA reservoir strain was associated with new-onset atrial arrhythmias (adjusted HR 0.95, 95% CI 0.93-0.97) after multivariable adjustment. Of 73 patients with new-onset atrial arrhythmia, 41 (56%) had recurrent atrial arrhythmia (atrial flutter/tachycardia n = 18; atrial fibrillation n = 23); annual incidence 11.2%. Similarly, RA reservoir strain was associated with recurrent atrial arrhythmias (adjusted HR 0.92, 95% CI 0.88-0.96) after multivariable adjustment.

CONCLUSIONS

RA strain indices can identify patients at risk for atrial arrhythmias, and this can in turn, be used to guide the type/intensity of therapy in such patients.

Right atrial function and fibrosis in relation to successful atrial fibrillation ablation

AIMS

Bi-atrial remodelling in patients with atrial fibrillation (AF) is rarely assessed and data on the presence of right atrial (RA) fibrosis, the relationship between RA and left atrial (LA) fibrosis, and possible association of RA remodelling with AF recurrence after ablation in patients with AF is limited.

METHODS AND RESULTS

A total of 110 patients with AF undergoing initial pulmonary vein isolation (PVI) were included in the present study. All patients were in sinus rhythm during cardiac magnetic resonance (CMR) imaging performed prior to ablation. LA and RA volumes and function (volumetric and feature tracking strain) were derived from cine CMR images. The extent of LA and RA fibrosis was assessed from 3D late gadolinium enhancement images. AF recurrence was followed up for 12 months after PVI using either 12-lead electrocardiograms or Holter monitoring. Arrhythmia recurrence was observed in 39 patients (36%) after the 90-day blanking period, occurring at a median of 181 (interquartile range: 122-286) days. RA remodelling parameters were not significantly different between patients with and without AF recurrence after ablation, whereas LA remodelling parameters were different (volume, emptying fraction, and strain indices). LA fibrosis had a strong correlation with RA fibrosis (r = 0.88, P < 0.001). Both LA and RA fibrosis were not different between patients with and without AF recurrence.

CONCLUSIONS

This study shows that RA remodelling parameters were not predictive of AF recurrence after AF ablation. Bi-atrial fibrotic remodelling is present in patients with AF and moreover, the amount of LA fibrosis had a strong correlation with the amount of RA fibrosis.

Provocation and localization of atrial ectopy in patients with atrial septal defects

Background

Atrial fibrillation (AF) is associated with atrial septal defects (ASDs), but the mechanism of arrhythmia in these patients is poorly understood. We hypothesised that right-sided atrial ectopy may predominate in this cohort. Here, we aimed to localise the origin of spontaneous and provoked atrial ectopy in ASD patients.

Methods

Following invasive calibration of P-wave axes, 24-h Holter monitoring was used to determine the chamber of origin of spontaneous atrial ectopy. Simultaneous electrogram recording from multiple intra-cardiac catheters was used to determine the chamber of origin of isoprenaline-provoked ectopy. Comparison was made to a group of non-congenital heart disease AF patients.

Results

Amongst ASD patients, a right-sided origin for spontaneous atrial ectopy was significantly more prevalent than a left-sided origin (24/30 patients with right-sided ectopy vs. 14/30 with left-sided ectopy, P = 0.015). Amongst AF patients, there was no difference in the prevalence of spontaneous right vs. left-sided ectopy. For isoprenaline-provoked ectopy, there was no significant difference in the proportions of patients with right-sided or left-sided ectopy in either group.

Conclusions

When spontaneous atrial ectopy occurs in ASD patients, it is significantly more prevalent from a right-sided than left-sided origin. Isoprenaline infusion did not reveal the predilection for right-sided ectopy during electrophysiology study.

Catheter ablation of atrial fibrillation using 2nd-generation cryoballoon in congenital heart disease patients - significance of RF ablation of additional atrial macro-reentrant tachycardia

Background

Prevalence of atrial fibrillation (AF) is increasing in adult patients with congenital heart disease (CHD). Experience using the cryoballoon to achieve pulmonary vein isolation (PVI) in adult CHD patients is limited. The aim of the present study was to assess the value of PVI by cryoballoon in adult CHD patients and to evaluate the significance of additional radiofrequency (RF) ablation of atrial tachycardia (AT).

Patients and methods

Prospective data analysis; all patients with CHD and AF and PVI using the cryoballoon from January 2017 through November 2021 were included.

Results

Nineteen patients with various types of CHD were included. Median age was 58 (IQR 47–63) years. A total of 12/19 (63%) patients had had RF ablation of right atrial AT before. Median procedure duration was 225 (IQR 196–261) min. Median fluoroscopy time was 12.3 (IQR 5.2–19.5) min and median freeze time was 32 (IQR 28–36.3) min. Procedural success was achieved in all patients. Additional RF catheter ablation of intraatrial reentrant tachycardia within the left atrium was performed in 3/19 (16%) subjects and within the right atrium in 6/19 (32%) patients. Median follow-up was 26 (IQR 9–49) months. Excluding a 90-day blanking period, recurrence of AF was observed in 6/19 subjects (32%). After one redo procedure deploying RF energy only, 84% of all patients remained free from recurrence. Phrenic nerve palsy was observed in 1 subject.

Conclusion

Results after PVI using the cryoballoon plus additional RF ablation of AT were promising (84% success including one redo procedure). Success of AF ablation was unsatisfactory in all patients who had no additional AT ablation. Ablation of any AT in these patients should therefore be considered in addition to PVI.