High Right Atrial Research Articles

Right atrial remodelling and prognosis in patients with severe atrial functional tricuspid regurgitation.

Atrial functional tricuspid regurgitation (AFTR) is increasingly recognized as a distinct cause of tricuspid regurgitation, yet data on outcomes and their determinants are limited. This study examines the prognostic role of right atrial (RA) remodelling in patients with severe AFTR. This retrospective study included consecutive patients with severe AFTR. The primary outcome was all-cause mortality. Cutoff values for RA and right ventricular (RV) sizes related to mortality were identified using receiver operating characteristic curves and maximally selected rank statistics. The cohort included 155 patients with severe AFTR, 96.1% of whom had atrial fibrillation. Of these, 121 received medical treatment, and 34 underwent surgery during follow-up. In the medical management group, 42 deaths (34.7%) occurred over a median of 3.3years. Patients with high RV end-diastolic area and RA area indices (>14.5cm2/m2 and >22cm2/m2) had significantly lower survival compared to their counterparts (P=0.012 and P=0.001, respectively). Cox analyses demonstrated that increased RV end-diastolic area and RA area indices were associated with higher mortality (RV end-diastolic area index, per 1cm2/m2 increase: adjusted hazard ratio 1.11, 95% confidence interval 1.02-1.22, P=0.019; RA area index, per 1cm2/m2 increase: adjusted hazard ratio 1.06, 95% confidence interval 1.02-1.10, P=0.006). Mortality was highest in patients with both high RV end-diastolic area index (>14.5cm2/m2) and RA area index (>22cm2/m2) and lowest in those with low values for both indices (P=0.001). In the surgical intervention group, four post-surgical deaths (11.8%) occurred exclusively in patients with both high RA area and RV end-diastolic area indices. RA and RV enlargement are poor prognostic factors in patients with severe AFTR. These findings underscore the importance of assessing RA and RV remodelling to optimize the timing of intervention in this population.

Abstract 4136316: BMP10 as novel marker for right atrial dilatation and pressure in precapillary pulmonary hypertension

Introduction: Precapillary pulmonary hypertension (precPH) leads to increased right atrial (RA) stretch and pressure. The right atrium is the major source of bone morphogenetic protein 10 (BMP10) in adults. Aim: This study aims to investigate BMP10 in relation to RA dilatation and pressure overload. Methods: We studied BMP10 mRNA in fresh RA tissue of N=5 Chronic Thromboembolic Pulmonary Hypertension (CTEPH) patients and N=9 controls and protein expression in paraffin-embedded RA tissue of N=4 Pulmonary Arterial Hypertension (PAH) patients and N=6 controls. We prospectively included 48 precPH patients (N=22 idiopathic PAH, N=14 hereditary PAH and N=12 CTEPH, and N=16 controls. To study BMP10-induced transcriptional activity, we assayed serum samples in human microvascular endothelial cells (HMEC) with a BMP-responsive transcriptional luciferase assay. BMP10 activity was calculated by subtracting BMP activity after incubation with antibodies for Alk1Fc and bone morphogenetic protein 9 (BMP9). We assessed correlations between BMP10 activity and RA dilatation (RA max volume>79 ml/m2 for male or >69 ml/m2 for female) and right ventricular (RV) dilatation (RV end-diastolic volume>108 ml/m2 for male and >96 ml/m2 for female). In a cohort of CTEPH patients that underwent pulmonary endarterectomy (PEA) we assessed the effect of pressure unloading on BMP10 activity. Normality of data was checked and statistical differences between groups were tested using an independent sample t-test or Wilcoxon rank-sum test. Results: BMP10 mRNA, protein and downstream activity were higher in the precPH RA tissue (Figure 1A-F). High systemic BMP10 activity was associated with RA dilatation and high RA pressure, but not RV dilatation in precPH (Figure 2A-C). Finally, pressure unloading after PEA in CTEPH patients results in a reduction in BMP10 activity (figure 2D). Conclusions: Local RA BMP10 expression and activity is increased in precPH. Increased systemic BMP10 activity was related to RA dilatation and pressure. Pressure unloading of the right heart leads to a reduction of systemic BMP10 activity. Future studies are needed to determine whether increased BMP10 release is an adaptative mechanism or can be used as therapeutic target.

Prognostic value of right atrial function in patients with significant tricuspid regurgitation.

Although right ventricular (RV) dysfunction is associated with adverse outcomes in tricuspid regurgitation (TR), the potential role of right atrial (RA) function is unknown. We aimed to investigate the relationship between RA function and clinical outcomes in patients with significant TR. This retrospective study included 169 outpatients with moderate or severe TR due to left-sided heart diseases who underwent transthoracic echocardiography between June 2020 and April 2023 (average age, 75±10years; male, 40%). Patients with atrial fibrillation were excluded from this study due to the inaccuracy of the evaluation using 2D speckle-tracking echocardiography. RA function was compared between patients with and without events, which were defined as all-cause mortality or hospitalization due to heart failure. RA function was calculated as RA global longitudinal strain (RAGLS) with the 2D speckle-tracking echocardiography. During a median follow-up of 13months, 19 patients had events (all-cause mortality: 14 cases, hospitalization due to heart failure: 5 cases). RAGLS was lower in patients with events than in those without events (13%±10% vs. 18%±9%, P=0.02). When the patients were categorized into two groups [low RAGLS≤16.2% vs. high RAGLS>16.2%, high RA volume index (RAVI)≥50mL/m2 vs. low RAVI<50mL/m2], Kaplan-Meier curves showed that patients with low RAGLS had higher event rates than those with high RAGLS (log-rank test, P=0.003). Patients with high RAVI had higher event rates than those with low RAVI (log-rank test, P<0.001). In the multivariate Cox regression analysis, low RAGLS (≤16.2%) was significantly associated with events in a model that included RV dysfunction (RV fractional area change≤35%) or high RAVI (≥50mL/m2) (hazard ratio: 4.55, 95% confidence interval: 1.51-13.71, P<0.01; hazard ratio: 4.57, 95% confidence interval: 1.52-13.79, P<0.01, respectively). RAGLS is associated with all-cause mortality and hospitalization due to heart failure in patients with significant TR. Our results suggest that RA function is a sensitive marker for identifying the risk stratification of significant TR.

Similarities and Differences between Three-Dimensional Speckle-Tracking Echocardiography-Derived Left and Right Atrial Volumes and Volume-Based Functional Properties in the Same Healthy Adults-A Detailed Analysis from the MAGYAR-Healthy Study.

Background and Objectives: It would be important to know what happens to the volume and volume-based functional properties of one atrium if the size of the other atrium is larger or smaller than the average. Therefore, the present study aimed to perform three-dimensional speckle-tracking echocardiography (3DSTE)-derived quantification of left atrial (LA) and right atrial (RA) volumes and volume-based functional properties to examine these associations in healthy adults with mean and lower or higher than mean atrial volumes. Materials and Methods: The present study consisted of 179 healthy volunteers with a mean age of 32.3 ± 12.3 years (92 males). Three-dimensional speckle-tracking echocardiography-derived LA and RA volumes and volume-based functional properties were determined in all cases. Results: When different LA or RA volume groups were evaluated, both LA and RA showed the same pattern of volume changes in all phases of atrial function with higher LA or RA volumes. In case of low and mean LA volumes, RA volumes were higher compared to their LA counterpart. In case of mean and high RA volumes, RA volumes proved to be higher as well. In case of mean LA or RA volumes, differences between LA and RA stroke volumes (SVs) could not be detected, but all atrial emptying fractions (EFs) were lower for RA than for LA. Some differences were detected in counterpart LA/RA total, passive, and active atrial SVs and EFs values in the presence of lower/higher than mean LA/RA volume. Conclusions: In case of mean LA or RA volumes, RA volumes are higher compared to their LA counterpart, LA-SVs and RA-SVs are similar, but atrial EFs are lower for RA than for LA. If lower/higher than mean LA or RA volumes are present, some differences in patterns of changes in counterpart atrial volumes-SVs and EFs-could be detected.

In silico biatrial fibrosis ablation improves atrial fibrillation outcome

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Medical Research Council Fellowship Background In DECAAF II, left atrial (LA) fibrosis ablation plus PVI did not improve AF outcome compared to PVI alone across the study cohort. We hypothesize that biatrial fibrosis ablation could improve AF ablation therapy outcome in a subset of patients with properties identified through a large virtual in silico trial. Purpose To investigate the effects of anatomy, fibrosis distribution, and LGE-MRI threshold on ablation outcome using a virtual cohort of 4000 patients. Methods We constructed 1000 biatrial models from a statistical shape model and we mapped pectinate muscles, Bachmann’s bundle and fibers from an atlas. For each of the 1000 anatomies we applied a randomly selected fibrosis map from a library of 100 clinical maps. We then created four versions of each case by assigning one of four randomly selected right atrial (RA) fibrosis distributions with Utah grades 1-4 (Fig 1A), giving 4000 virtual patients. Four ablation approaches were applied to each patient model after 5 seconds of AF: PVI, PVI &amp; LA fibrosis, PVI &amp; RA fibrosis, PVI &amp; biatrial fibrosis. LGE-MRI was thresholded for fibrosis ablation at either 1.2 or 1.32 image intensity ratio (IIR). The outcome was classified 5 seconds post ablation. Results Biatrial fibrosis ablation is more effective than LA ablation. For patients with high (Utah 4) RA fibrosis, biatrial fibrosis ablation increases AF termination compared to LA fibrosis ablation (Figs 1B &amp; 2A: 62% vs 14%), this compares to cases with low (Utah 1) RA fibrosis (21% vs 14%). For patients with high LA (Utah 4) fibrosis, biatrial ablation is more effective than LA ablation (Fig 2B: 52% vs 19%), this compares to patients with low (Utah 1) LA fibrosis (17% vs 7%). Increasing IIR threshold for ablation decreases termination (LA fibrosis ablation: 15.8% termination at IIR 1.2, 11.0% at IIR 1.32; biatrial: 41.5% at IIR1.2; 20.3% at IIR1.32). Anatomy has a larger effect on biatrial ablation outcome (31.2% of outcomes change between anatomies) than on PVI only ablation outcome (20.0% change). Conclusion Biatrial fibrosis ablation is superior to LA fibrosis ablation for cases with high RA fibrosis. Biatrial fibrosis distribution should be considered when targeting AF ablation therapy.

Elevated Right And Left Sided Filling Pressures Determine Adverse Outcomes In Ambulatory Heart Failure With Preserved Ejection Fraction

Elevated Right And Left Sided Filling Pressures Determine Adverse Outcomes In Ambulatory Heart Failure With Preserved Ejection Fraction

The Detrimental Effect of RA Pacing on LA Function and Clinical Outcome in Cardiac Resynchronization Therapy

The Detrimental Effect of RA Pacing on LA Function and Clinical Outcome in Cardiac Resynchronization Therapy

Prolonged Sinus Pauses upon Termination of Paroxysmal Atrial Fibrillation: Abnormal Right Atrial Electrophysiologic and Electroanatomic Findings.

The efficacy of pulmonary vein antral isolation for patients with prolonged sinus pauses (PSP) on termination of atrial fibrillation has been reported. We studied the right atrial (RA) electrophysiologic and electroanatomic characteristics in such patients. Forty patients underwent electroanatomic mapping of the RA: 13 had PSP (group A), 13 had no PSP (group B), and 14 had paroxysmal supraventricular tachycardia (control group C). Group A had longer P-wave durations in lead II than did groups B and C (115.5 ± 15.4 vs 99.5 ± 10.9 vs 96.5 ± 10.4 ms; P=0.001), and RA activation times (106.8 ± 13.8 vs 99 ± 8.7 vs 94.5 ± 9.1 s; P=0.02). Group A's PP intervals were longer during adenosine triphosphate testing before ablation (4.6 ± 2.3 vs 1.7 ± 0.6 vs 1.5 ± 1 s; P <0.001) and after ablation (4.7 ± 2.5 vs 2.2 ± 1.4 vs 1.6 ± 0.8 s; P <0.001), and group A had more complex electrograms (11.4% ± 5.4% vs 9.3% ± 1.6% vs 5.8% ± 1.6%; P <0.001). Compared with group C, group A had significantly longer corrected sinus node recovery times at a 400-ms pacing cycle length after ablation, larger RA volumes (100.1 ± 23.1 vs 83 ± 22.1 mL; P=0.04), and lower conduction velocities in the high posterior (0.87 ± 0.13 vs 1.02 ± 0.21 mm/ms; P=0.02) and high lateral RA (0.89 ± 0.2 vs 1.1 ± 0.35 mm/ms; P=0.04). We found that patients with PSP upon termination of atrial fibrillation have RA electrophysiologic and electroanatomic abnormalities that warrant post-ablation monitoring.

Temporal sinus node modification by high-dose continuous intravenous administration of landiolol in a patient with persistent inappropriate sinus tachycardia

Temporal sinus node modification by high-dose continuous intravenous administration of landiolol in a patient with persistent inappropriate sinus tachycardia

Right-to-left frequency gradient during atrial fibrillation initiated by right atrial ectopies and its augmentation by adenosine triphosphate: Implications of right atrial fibrillation

Right-to-left frequency gradient during atrial fibrillation initiated by right atrial ectopies and its augmentation by adenosine triphosphate: Implications of right atrial fibrillation

Discrimination of Thoracic Vein Potentials Facilitated by Atrial Pacing during the Isolation

Although electrical thoracic vein (TV) isolation is an established strategy during atrial fibrillation (AF) ablation, discriminating TV potentials from far-field signals is critical for the achievement. One hundred consecutive drug-refractory symptomatic paroxysmal AF patients who underwent AF catheter ablation were included. All patients underwent circumferential pulmonary vein (PV) isolation during distal coronary sinus (CS) pacing with a cycle length of 600 ms. A superior vena cava (SVC) isolation was added during high right atrial (HRA) pacing with the same cycle length in 79 patients in whom SVC potentials were identified. The interval between the near-field PV potentials and far-field atrial signals significantly prolonged more during distal CS pacing than sinus rhythm (SR) in the left superior (26.0 [18.5-32.8] ms to 36.0 [24.3-55.5] ms, P < 0.01) and left inferior PVs (21.0 [14.0-30.0] ms to 40.0 [23.0-56.0] ms, P < 0.01), but not in the right superior (34.0 [20.0-40.0] ms to 23.0 [18.0-36.0] ms, P = 0.13) and right inferior PVs (22.0 [16.0-28.0] ms to 25.0 [18.0-38.0] ms, P = 0.05). The interval between the SVC potentials and far-field atrial signals significantly prolonged more during HRA pacing than SR (20.0 [0-32.0] ms to 34.0 [24.0-46.0] ms, P < 0.01). Electrical isolation was successfully achieved in all TVs without any complications except for transient right phrenic nerve palsy in two patients. Discrimination of ipsilateral left PVs and SVC potentials is facilitated by pacing from the distal CS and HRA, respectively. Better recognition of TV potentials would help to achieve electrical isolation.

Right atrial volume and body mass index in corrected tetralogy of Fallot correlate with the incidence of supraventricular arrhythmia - an MRI study

Background Patients with corrected Tetralogy of Fallot (cTOF) can develop supraventricular arrhythmias. So far, right atrial (RA) volume in TOF has not been evaluated in the context of arrhythmia. The aim of this study was to evaluate if right atrial (RA) volume in TOF correlates with the occurrence of supraventricular arrhythmias. To identify other risk factors for arrhythmias additional parameters were included in the analysis: anthropomorphic parameters (BMI, age, gender), previous shunt, high right ventricular (RV) volumes and pulmonary regurgitation (PR). Methods Cardiac MRI (CMR) and 24h Holter ECG-monitoring were performed in 69 consecutive patients with cTOF (Table 1). CMR protocol included triplanar HASTE sequences, standard SSFP cine images, flow measurements of the aorta, pulmonary trunk and pulmonary arteries. RA and LA volumes were retrieved from HASTE sequences and SSFP cine images. Results Mean values for RA volume were 49 +-19 ml/m 2 from HASTE sequences. In 23 patients endsystolic and enddiastolic RA-volumes were obtained from cineSSFP and compared to HASTE sequences. Bland-Altman analysis confirmed correlation of RA volumes from both sequences in atrial diastole with minimal overestimation by HASTE sequences. Mean RV volumes were 97 +-27 ml/m 2 ,p ulmonary valve regurgitation fraction 21 +-19 %. Mean heart rate on Holter was 75, ranging from from 52 to 124 bpm. 57 of 69 patients had supraventricular arrhythmias as singular extrasystolies, couplets or short runs. Mean BMI was 25 kg/m 2 with a range from 15.5 to 36 kg/m 2 . Based on multivariate regression analysis RA volume (p<0.01) as well as BMI (p<0.01) were identified as independent risk factors for supraventricular arrhythmias. No correlation was found for gender, age, previous shunt, RV volume or degree of residual pulmonary regurgitation. Conclusions TOF patients with high RA volumes or high BMI exhibited supraventricular arrhythmias more often, regardless of age, gender, previous shunt, RV volume or PR.

Acute Hemodynamic Benefits of Bi-Atrial Atrioventricular Sequential Pacing With the Optimal Atrioventricular Delay

Acute Hemodynamic Benefits of Bi-Atrial Atrioventricular Sequential Pacing With the Optimal Atrioventricular Delay

Effectiveness of rhythm control in persistent or permanent atrial fibrillation with overdrive atrial pacing and antiarrhythmic drugs after linear right atrial catheter ablation

Effectiveness of rhythm control in persistent or permanent atrial fibrillation with overdrive atrial pacing and antiarrhythmic drugs after linear right atrial catheter ablation

Effect of Chronic Right Atrial Stretch on Atrial Electrical Remodeling in Patients With an Atrial Septal Defect

Adults with an atrial septal defect (ASD) frequently develop late atrial arrhythmias. We sought to characterize the pattern and persistence of atrial electrical remodeling caused by chronic right atrial (RA) stretch in this group. Thirteen ASD patients without atrial arrhythmia (42+/-10 years old; RA volume, 65+/-16 mL) and 17 normal control subjects (44+/-11 years old; RA volume, 38+/-8 mL) had electrophysiological study to measure (1) atrial effective refractory period (AERP) from the low lateral/high lateral/high septal RA and distal coronary sinus (CS), (2) dispersion of AERP, (3) lateral-RA and CS conduction time during constant pacing, (4) conduction delay across the crista terminalis measuring the number of crista catheter bipoles (0-10) recording discrete double potentials during pacing, (5) corrected sinus node recovery time, and (6) P-wave duration. After ASD closure (8.3+/-5.6 months), follow-up echo studies (n=12) and electrophysiological study (n=4) were performed. The low-lateral AERP, P-wave duration, sinus node recovery time, and extent of conduction delay across the crista terminalis were significantly greater in ASD patients. No differences were found for other measured electrophysiological study parameters. At follow-up, there was incomplete resolution of RA volume (47+/-12 mL; P<0.01 versus before surgery), a trend toward shortening of the AERP at the lateral RA and an increase at the distal CS and high septal RA, but persisting extensive, widely split crista double potentials. Chronic RA stretch because of ASD causes electrical remodeling with modest increases in RA ERP, conduction delay at the crista terminalis, and sinus node dysfunction. Conduction delay at the crista terminalis persists beyond ASD closure and may contribute to the long-term atrial arrhythmia substrate in this condition.

Improved suppression of recurrent atrial fibrillation with dual-site right atrial pacing and antiarrhythmic drug therapy

Improved suppression of recurrent atrial fibrillation with dual-site right atrial pacing and antiarrhythmic drug therapy

Electrophysiology and endocardial mapping of induced atrial fibrillation in patients with spontaneous atrial fibrillation

Electrophysiology and endocardial mapping of induced atrial fibrillation in patients with spontaneous atrial fibrillation

Coronary sinus pacing prevents induction of atrial fibrillation.

Atrial fibrillation (AF) is due to reentry, and its incidence has been shown to decrease after dual-site atrial or biatrial pacing. We investigated whether a simpler pacing approach via the distal coronary sinus (CSd) could eliminate AF inducibility by high right atrial (HRA) extrastimuli (APDs). We based our hypothesis on our previous observation that AF inducibility by HRA APDs was associated with conduction delays to the posterior triangle of Koch, whereas AF was never induced with CSd APDs, which were associated with minimal intra-atrial conduction delays. Programmed electrical stimulation was performed from the high right atrium and CSd, and bipolar recordings were obtained from the high right atrium, His bundle, posterior triangle of Koch, and coronary sinus. In 13 patients (age, 44+/-18 years), AF was reproducibly induced with a critically timed HRA APD (220+/-22 ms) delivered during HRA pacing. AF was not induced in any of the patients when HRA APDs were delivered during CSd pacing at the same critical coupling intervals. Coronary sinus APDs delivered during HRA pacing also were not associated with AF induction. The APD coupling interval measured at the posterior triangle of Koch during CSd pacing was significantly prolonged compared with the one measured during HRA pacing and AF induction (381+/-58 versus 263+/-37 ms; P<.0001). We propose that CSd pacing suppresses the propensity of HRA APDs to induce AF by limiting their prematurity at the posterior triangle of Koch and not allowing local conduction delay and local reentry to occur.

Mechanisms of entrainment of human common flutter studied with multiple endocardial recordings.

The mechanisms of common atrial flutter entrainment have not been directly studied in humans. Endocardial mapping in six cases of common flutter showed large right atrial (RA) reentry circuits. Activation was craniocaudal in the anterolateral right atrium and caudocranial in the septum. The inferior vena cava-tricuspid isthmus (IVC-TV) closed the circuit. The high right atrium was paced at progressively shorter cycle lengths (CLs) in all, and the IVC-TV was paced in three cases. We recorded six to eight simultaneous RA electrograms from septum and anterior wall. Transient entrainment was recognized from all sites by capture of all electrograms at two or more paced CLs, with total or partial preservation of baseline flutter sequence and return to baseline after pacing. Antidromic circuit penetration was documented in five cases during high RA pacing and in one with IVC-TV pacing. Short CLs induced orthodromic conduction delays that resulted in a postpacing pause longer than basal flutter CL. ECG fusion with high RA pacing correlated poorly with antidromic septal penetration. This was related to overlap of orthodromic septal activation with anterior wall activation of the following cycle. Pacing disorganized flutter into a brief irregular rapid rhythm in two cases and atrial fibrillation in one case. In two cases, complete antidromic septal penetration led to sudden flutter interruption, and in another case it led to circuit inversion. Direct recordings confirm orthodromic and antidromic penetration of flutter circuits by high and low RA pacing. Short CLs modify the circuit. Disorganization is the most common mode of flutter interruption.

Left atrial electrograms recorded through the patent foramen ovale.

The presence of a patent foramen ovale allows direct recording of a left atrial (LA) electrogram. Three patients are reported in whom simultaneous high right atrial (HRA), coronary sinus (CS), and direct LA electrograms were obtained. In two patients with normal surface ECG P waves the direct LA lead depolarized before the CS or low RA. The HRA to LRA and HRA to CS conduction times were similar to those reported previously. In a patient with a prolonged surface ECG P wave, the direct LA electrogram occurred late and after low RA depolarization. Recording LA electrograms through a patent foramen ovale is a useful technique, and these defects should be sought in all patients undergoing electrophysiological study.