Right Atrial Volume Research Articles

Right Atrial Strain in Preterm Infants With a History of Bronchopulmonary Dysplasia.

BACKGROUNDFew studies have utilized right atrial (RA) strain to evaluate right ventricular (RV) diastolic dysfunction in preterm infants with bronchopulmonary dysplasia (BPD). We aimed to evaluate the associations of RA strain with BPD severity and respiratory outcomes in preterm infants with BPD.METHODSWe retrospectively studied 153 infants with BPD born before 32 weeks of gestational age at CHA Bundang Medical Center. Peak longitudinal right atrial strain (PLRAS) was obtained using velocity vector imaging and compared among infants across BPD severity. Conventional echocardiographic parameters and clinical characteristics were also evaluated.RESULTSIn infants with severe BPD, mean gestational age (27.4 ± 2.1 weeks) and mean birth weight (971.3 ± 305.8 g) were significantly smaller than in those with mild BPD (30.0 ± 0.9 weeks, 1,237.3 ± 132.2 g) and moderate BPD (29.6 ± 1.3 weeks, 1,203.2 ± 214.4 g). PLRAS was significantly lower in infants with severe BPD (26.3 ± 10.1%) than in those in the moderate BPD group (32.4 ± 10.9%) or mild BPD group (31.9 ± 8.3%). Tricuspid E/e′ and maximum RA volume index were similar across BPD severity. A decrease in PLRAS was significantly correlated with increased duration of mechanical ventilation duration; however, tricuspid E/e′ and maximum RA volume index were not.CONCLUSIONSEvaluating PLRAS with other parameters in infants with BPD might detect RV diastolic dysfunction. Longer follow-up and larger study populations may elucidate the association between PLRAS and respiratory outcomes in infants with BPD.

145 Prognostic value of three-dimensional echocardiographic assessment of tricuspid valve geometry in atrial and ventricular functional tricuspid regurgitation

Abstract Aims Atrial and ventricular functional tricuspid regurgitation (A-FTR and V-FTR) have recently emerged as different phenotypes of FTR. Given the difference in mechanisms that are postulated to be underlying these two entities, a different remodelling of tricuspid valve (TV) apparatus can occur and therefore also a specific quantitative approach could be deemed. Moreover, considered the known limitation of the two-dimensional flow convergence method (2D-PISA) for quantifying FTR in advanced valve apparatus remodelling with irregular effective valve orifice (ERO) morphology, it would be expected that also the parameters of severity of FTR can be different in these two types of FTR. The aim of this study was to investigate the TV apparatus remodelling in the two different phenotypes of FTR: ventricular (V-FTR) and atrial (A-FTR) and the role of echocardiographic parameters of TV remodelling and TR severity to predict clinical outcomes. Methods and results The present retrospective study included consecutive patients with moderate to severe functional tricuspid regurgitation (FTR) referred for echocardiography in two Italian centres. The composite endpoint of death for any cause and heart failure (HF) hospitalization was used as primary outcome of this analysis. According to more recent guidelines, patients were considered having A-FTR if having history of long-standing atrial fibrillation, without history of pulmonary hypertension and left side heart disease. A total of 180 patients were included. Despite the right atrial volume (RAV) was not different in the two groups, in A-FTR tethering height was significantly lower (11.7 ± 4.8 mm vs. 15.0 ± 5.5 in V-FTR. P < 0.01) and the 3D-derived tricuspid annulus (TA) diameters were larger both in end-diastolic and mid-systolic phase (3D-TA-End diastolic-major axis: 45.2 ± 6.2 mm in A-FTR vs. 42.8 ± 5.4 in V-FTR. P = 0.04; 3D-TA mid systolic major axis: 41.7 ± 6.4 mm in A-FTR vs. 37.9 ± 5.1 in V-FTR, P < 0.01). 3D-TA-End diastolic-minor axis: 39.7 ± 6.8 vs. 37.1 ± 5.2. P = 0.03. Regarding the parameters of severity of FTR, patients with V-FTR had larger vena contracta (VC), either when 2D estimated or 3D (2D-VC-average: 5.3 ± 2.8 mm in A-FTR vs. 6.6 ± 3.7 in V-FTR. P = 0.02; 3D-VCA: 0.9 ± 0.4 cm2 vs. 1.3 ± 1.1 cm2, P = 0.02); conversely the value of 2D-ERO and regurgitant volume estimated with 2D-PISA method did not show significant difference between the two groups. After a median follow-up of 24 months (IQR: 2–48) 72 patients (40%) reached the primary endpoint and 64 (36%) hospitalized for HF. Different predictors of combined endpoint were found in the two groups: tenting height. 2D-VC. 3D-VCA and regurgitant fraction were prognostic correlates in V-FTR; TA dimensions as well as all the parameters of severe TR, including EROA with PISA method were related to the prognosis in A-FTR. Conclusions Different TV remodelling occurs in patients with A- and V-FTR, having the second more pronounce tethering of TV leaflets; the prognostic role of quantitative parameters of FTR in these two groups is different, thus reaffirming: (1) the limitation of PISA method without correction in case of more pronounced tenting of leaflets; (2) the difference in underlying pathogenic mechanisms; and (3) the needing for a more specific diagnostic approach and prognostic stratification in these two FTR phenotypes.

204 Permanent his bundle pacing using stylet-driven lead in patients with right atriomegaly: a single-centre experience

Abstract Aims His bundle pacing (HBP) is becoming an increasing widespread approach for physiological pacing. However, successful HBP procedure could be hampered by limited implantation tools especially in challenging anatomies. We aimed to report our experience with HBP technique using a novel stylet-driven lead system in patients with right atriomegaly. Methods and results Consecutive patients with right atrium (RA) volume >25 ml/m2 in men and >21 ml/m2 in women who underwent permanent HBP for standard indications were enrolled from March 2020 to March 2021. The tool of first choice for HBP attempt was a stylet-driven lead (Solia S 60, Biotronik) delivered via a dedicated introducer sheath (Selectra 3D, Biotronik). The acute, 1-month and 6-month procedural success rates were assessed. We enrolled 24 patients [median age: 75 (70–79) years, 85% men] with an average RA volume of 50.7 ± 7.8 ml/m2. At implant, conduction system pacing using stylet-driven lead was achieved in 21 patients (87%): 12 (50%) selective HBP, 6 (25%) non-selective HBP, and 3 (12.5%) left bundle branch area pacing. In the three failures, HBP was further attempted with a lumen-less lead with fixed helix (SelectSecure 3830, Medtronic) with final procedural success in two cases. In the successful cases, there was a significant reduction of QRS duration between paced and spontaneous beats [152.5 (130–167.5) ms vs. 130 (122.5–137.5) ms, P = 0.003]. No lead dislodgment nor significant pacing threshold increase was observed at 1-month (1.30 ± 0.76 V@0.4 vs. 1.32 ± 0.80 V@0.4 ms, P > 0.9) and 6-month follow-up (1.30 ± 0.76 V@0.4 vs. 1.38 ± 0.97 V@0.4 ms, P = 0.66). Conclusions In patients with right atriomegaly, the novel stylet-driven lead system showed high implant success rates with stable pacing thresholds.

144 Atrial and ventricular phenotypes in a cohort of patients with functional tricuspid regurgitation: clinical, echocardiographic, and prognostic aspects

Abstract Aims Atrial functional tricuspid regurgitation (A-FTR) has emerged as a newly recognized phenotype of functional tricuspid regurgitation (FTR), occurring in patients with atrial fibrillation and right atrial (RA) dilation but normal right ventricular (RV) size and function. Its prevalence, echocardiographic features, and prognosis have not yet clarified since most evidence to date has included indiscriminately FTR patients with A-FTR and ventricular form (V-FTR). Aim of this study was to investigate the differences between these two phenotypes of FTR in terms of clinical correlates, echocardiographic aspects, and prognosis. Methods and results A total of 180 consecutive patients with moderate to severe FTR referred for echocardiography in two Italian centres were retrospectively enrolled. A-FTR was defined as: (1) longstanding atrial fibrillation; (2) PASP <50 mmHg; (3) left ventricular ejection fraction > 60% (complete according to the ACC guidelines); and (4) no significant left side valve disease. 3D TTE was used for the quantitative assessment of TR and chamber sizing and function. The composite endpoint of death for any cause and heart failure (HF) hospitalization was used as primary outcome of this analysis; secondary endpoint was HF-hospitalization. Patients with A-FTR were 30% of the population; they were older than those one with V-FTR; with higher systolic blood pressure and less advanced symptoms. Chronic obstructive pulmonary disease was more prevalent in V-FTR. Patients with V-FTR had larger 3D-derived right ventricle (RV) volumes, both diastolic and systolic, while right ventricle ejection fraction (RVEF) was similar. RV functional parameters as TAPSE, RVFWLS, and RVGLS were significantly lower in the V-FTR patients as well as all the parameters of RV-pulmonary arterial (PA) coupling. After a median follow-up of 24 months (IQR: 2–48), 72 patients (40%) reached the primary endpoint and 64 (36%) hospitalized for HF. The rate of composite endpoint tended to be lower in A-FTR than in V-FTR (29% vs. 44%, P-value: 0.1); the rate of hospitalization for HF was higher in V-FTR patients (22% vs. 41%, P-value: 0.04). Correlates of combined endpoint in both groups were: functional class of dyspnoea (NYHA class III–IV vs. I–II), severe TR grade (HR in V-FTR: 2.88 [1.63–5.06], P < 0.01; HR in A-FTR: 8[3–17], P < 0.01); RV volumes, RA volumes. Estimated SPAP as well as all the parameters of RV function and of RV-PA coupling were correlates of prognosis only in V-FTR; conversely, parameters of TA dimensions were related to combined Endpoint in A-FTR phenotype, while RV function and RV-PA coupling indexes did not. Conclusions Patients having A-FTR have an incidence of combined endpoint slightly different, without reaching a statistically significant difference, thus remarking the fact that A-FTR could not be considered ‘more benign’ and should therefore be targeted. Prognostic predictors are different between A-.FTR and V-FTR patients.

Abstract 11168: Right Atrial Adaptation in Pulmonary Hypertension: In-Depth Pressure-Volume Analysis

Introduction: Pulmonary hypertension (PH) is associated with increased right atrial (RA) pressure and volume. We hypothesized that RA stroke work and RA stiffness are higher in PH patients in comparison to healthy controls. Methods: RA PV loops were created through a novel method. RA volume was measured throughout the cardiac cycle on a magnetic resonance transverse stack of slices (typically 8-10). RA pressure was averaged over at least 10 cardiac cycles and approximately two respiratory cycles. Alignment of RA volume and pressure was done based on the v-wave (peak during ventricular contraction, see figure). RA stroke work was calculated as the area under the PV loop from the p-wave (start of atrial contraction) to the minimal RA volume. RA active emptying as the difference between p-wave and minimal volume. An exponential curve was fitted through the reservoir portion of the PV loop from the x-descent to the v-wave. The slope of this curve at the v-wave (RA end-reservoir elastance) was determined as a measure of RA stiffness. Results: RA PV loops were created for healthy controls (n=9) and PH patients (n=27). The averaged PV loops in the figure show RA dilatation in PH patients as well as elevated pressure, especially during atrial contraction. The difference between RA maximal pressure and p-wave pressure was higher in PH patients in comparison with controls (4.01 [3.12-6.75] vs 2.83 [2.54-3.06] mmHg; p=0.001). RA stroke work (493±253 vs 171±50 mmHg*ml; p=0.001) and active emptying (41±13 vs 23±5 ml; p<0.001) were also higher in PH, while RA end-reservoir elastance was not (0.26 [0.23-0.37] vs 0.33 [0.24-0.64] mmHg/ml; p=0.22). Conclusions: PH patients have increased RA stroke work and active emptying, as assessed with a novel method to derive RA PV loops. They do not show signs of RA stiffening. Future associations with right ventricular diastolic stiffness will show whether RA stroke work is able to match the increase in RA afterload.

Abstract 9675: Right Ventricular and Right Atrial Function in Pulmonary Hypertension Secondary to Heart Failure With Preserved Ejection Fraction: A Comparison With Pulmonary Arterial Hypertension

Introduction: Heart failure with preserved ejection fraction (HFpEF) is a prevalent condition for which no treatment exists. Pulmonary hypertension (PH) and right atrial (RA) and right ventricular (RV) dysfunction are frequently observed. The question remains whether PH and the associated RV/RA dysfunction in HFpEF are treatment targets or a mere reflection of disease severity. Methods: To study the relative contribution of pressure-overload and left-to-right interaction, we compared RA/RV function in three groups: 1. HFpEF (n=13); 2. HFpEF-PH (n=33), and; 3. pulmonary arterial hypertension (PAH) matched to pulmonary artery pressures of HFpEF-PH (n=47). Patients underwent right heart catheterization and cardiac magnetic resonance imaging. Groups were compared using one-way ANOVA, after which post-hoc analysis with unpaired t-test and Bonferroni correction was performed. Results: The right ventricle in HFpEF-PH was less dilated and hypertrophied than in PAH and RV ejection fraction was more preserved (HFpEF-PH: 52±11 vs. PAH: 36±12%). RV filling patterns were altered: vena cava backflow during RA contraction was observed in PAH only. In HFpEF-PH, RA pressure was elevated throughout the cardiac cycle (HFpEF-PH: 10[8-14] vs. PAH: 7[5-10] mmHg), while RA volume was smaller, reflecting excessive RA stiffness (HFpEF-PH: 0.14[0.10-0.17] vs. PAH: 0.08[0.06-0.11]mmHg/mL). RA stiffness was associated with an increased RA eccentricity index (HFpEF-PH: 1.3±0.2 vs PAH: 1.2±0.1) and transmural pressure gradient (9[5-12] vs 2[-2-5] mmHg). Conclusions: Despite similar pressure-overload, RV/RA function was less compromised in HFpEF-PH than in PAH. Increased RA pressure and stiffness in HFpEF-PH were explained by left atrial/RA-interaction. Our results indicate that increased RA pressure is not a sign of overt RV failure, but rather a reflection of HFpEF-severity.

Abstract 10462: Increased Bone Morphogenetic Protein 10 Activity is Associated with Increased Right Atrial Wall Stress and Disease Severity in Pulmonary Hypertension

Background: Pulmonary Hypertension (PH) is characterized by increased right atrial (RA) stretch and pressure. The major predisposing risk factor for PH involves mutations in bone morphogenetic protein (BMP) receptor 2 (BMPR2), for which BMP9 and BMP10 are ligands. In adults, BMP10 is produced by RA cardiomyocytes, however, the mechanism to BMP10 release is unknown. We hypothesize that RA wall stress may be a trigger for BMP10 secretion. Methods: We determined BMP10 and BMP9 levels in plasma samples from PH-patients (22 idiopathic pulmonary arterial hypertension (iPAH), 14 hereditary PAH (hPAH) and 11 chronic thromboembolic PH (CTEPH)) and 16 controls by ELISA. To study BMP10 and BMP9 activity, we exposed endothelial cells to 10% serum and analyzed BMP-activity as read out of the BRE-luciferase reporter assay. Serum was incubated with trap antibodies: anti-BMP9 to inhibit BMP9 ligand, and ALK1-Fc to inhibit both BMP9 and BMP10 ligands. BMP9 and BMP10 activity were deducted from the difference vs baseline and BMP9-activity, respectively. Results: Circulating BMP10 levels were higher in PH-patients: 16.5 [9.5-69.7] pg/mL in iPAH, 17.1 [1.4-113.4] pg/mL in hPAH and 37.8 [10.7-87.1] pg/mL in CTEPH, vs 6.1 [0-8.7] pg/mL in controls (A). No differences were observed in BMP9 levels (B). BMP10 and BMP9 activity appeared lower in iPAH, only a trend was seen in BMP9-activity in iPAH vs hPAH (C,D). Next, we divided the PH cohort on median BMP10-activity. Higher active BMP10 in PH was associated with an increase in RA volume and pressure, and reduced RA compliance (E). Further, higher BMP10-activity in PH-patients was associated with worse disease status, shown by worse right ventricular function, lower stroke volume and increased NTproBNP (F). Conclusions: BMP10 circulating levels were increased in PH, whereas no difference in circulating BMP10-activity was observed. High BMP10-activity was associated with increased RA wall stress and disease severity in PH-patients.

Temporal trends in right heart strain in patients undergoing pulmonary thromboendarterectomy for chronic thromboembolic pulmonary hypertension.

Pulmonary thromboendarterectomy (PTE) is a curative procedure for chronic thromboembolic pulmonary hypertension (CTEPH). Right ventricular free wall strain (RV FWS) and right atrial strain (RAS) are not well studied in a CTEPH population. We sought to determine temporal trends in RAS and RV FWS in patients post-PTE. 28 patients undergoing PTE for CTEPH were prospectively enrolled in a surgical database. Comprehensive echocardiographic assessment of the right heart was performed including RV FWS, right atrial volume, and the three components of RAS: reservoir, conduit, and booster strain. Patients undergoing PTE demonstrated improvement in NYHA functional class (P<0.001). Hemodynamic assessment showed improvement in mean pulmonary artery pressure from 49.7±8.5mm Hg to 23.9±6.5mm Hg (P<0.001) and pulmonary vascular resistance decreased from 7.8±3.2 wu to 2.4±1.3 wu (P<0.001). Tricuspid annular plane systolic excursion (TAPSE) and lateral S` declined immediately post-op. RV FWS improved from -14.4±4% to -19±3.4% post-op and -21.2±4.7% at long-term follow-up (P<0.001). Improvement in RV FWS post-op was driven primarily by increases in the apical and mid segments. RA volume declined significantly during the study period. RA reservoir and conduit strain improved after PTE. Patients undergoing PTE for CTEPH had significant improvement in right heart hemodynamics immediately post-op. Traditional echo metrics of RV performance including TAPSE and lateral S` did not improve. RV FWS improved, which was driven by changes in the apical and mid segments. This highlights that RV FWS is a viable and useful metric to follow in CTEPH patients post-PTE.

Cardiac MRI risk factors predict atrial arrhythmia development in repaired tetralogy of Fallot patients

Abstract Background/Introduction Tetralogy of Fallot (TOF) patients with atrial arrhythmias (AA) experience greater morbidity and mortality than do their arrhythmia-free counterparts. Cardiac MRI (cMRI) has proven useful in elucidating risk factors for arrhythmia development in this population, but more work needs to be done to assess the efficacy of predicting AA onset. Purpose To evaluate demographic and clinical metrics, including those routinely assessed on cMRI, that predict AA onset in repaired TOF. Methods 175 repaired TOF patients ≥18 years of age and without prior AA undergoing initial cMRI between 2003 and 2020 were identified from a tertiary U.S. hospital database. Subsequent development of AA (specifically atrial fibrillation, atrial flutter, and atrial tachycardia) was evaluated by chart review and device checks (if present). Kaplan-Meier analysis was used to assess arrhythmia-free survival based on cMRI characteristics, and log-rank test used to compare differences in survival curves. Cutoff values for Kaplan-Meier analysis were the mean value (for the respective variable being measured) of our cohort at the time of their initial cMRI. Results Over a median follow-up of 3.3 years, 30 patients (17%) developed AA, including 16 with atrial fibrillation (53%), 20 with atrial flutter (67%), and 2 with atrial tachycardia (7%). Age at cMRI (p&amp;lt;0.01), history of hypertension (p=0.01), and time from birth to complete TOF repair (p&amp;lt;0.05) predicted AA. cMRI predictors included indexed right ventricular (RV) end diastolic and systolic volumes (both p&amp;lt;0.01), as well as indexed right atrial (RA) volume (p&amp;lt;0.05) and pulmonic regurgitation (PR) fraction (p&amp;lt;0.05). Indexed RV and RA volumes but not left sided chamber volumes predicted the development of atrial fibrillation. All Kaplan-Meier survival distributions were significantly different with the exception of those for right atrial volumes. Conclusions Our study suggests that RA and RV volumes may play a valuable role in predicting atrial arrhythmia onset in the repaired TOF population. Disease progression in a predominantly right-sided heart disease may play a role in predicting the onset of both “right sided” arrhythmias such as atrial flutter, as well as “left sided” arrhythmias such as atrial fibrillation. Additionally, the increased AA burden in patients with mild RV dilation seen in our study may suggest a potential benefit to early pulmonic valve replacement in this patient group. Funding Acknowledgement Type of funding sources: None. Clinical and cMRI CharacteristicsKaplan-Meier Survival Analysis

Diameter and shunt act as an alleviator of pulmonary hypertension: an echocardiography assessment of patients with ostium secundum atrial septal defect

Abstract Background Ostium-secundum atrial septal defect (OS-ASD) increases pulmonary arterial systolic pressure (PSAP) and eventually leads to pulmonary hypertension (PH). Nevertheless, whether the characteristics of OS-ASD could serve as an alleviator within chronic-volume overload in the right atrium (RA) is unclear. Aims To evaluate a potential interaction of OS-ASD diameter and the shunt (Qp/Qs ratio) on PSAP values in patients with secondary PH. Methods We designed a cross-sectional study of 63 adult patients with OS-ASD. A conventional transthoracic echocardiography was performed using Vivid 9X-clear equipment (GE Vingmed Ultrasound, Horten, Norway) to evaluate the OS-ASD diameter and the Qp/Qs ratio. The PSAP was calculated by tricuspid regurgitation velocity with continuous-wave Doppler in the apical four-chamber view. Polynomic adjusted correlations were performed between the RA volume and the PSAP; we evaluated a double and triple interaction-effect of the OS-ASD diameter and Qp/Qs ratio, respectively adjusted for age, sex and body surface area. Results In our study population, 78% (n=49) were female, with a mean age of 41.8 (±15) years. 44% (n=28) with mild-PH, 38% (n=24) with moderate-PH and 17% (n=11) with severe-PH. Mean echocardiographic parameters were: RA volume 58.8 (±26.4) mL, PSAP of 55.9 (±20.7) mmHg, OS-ASD diameter 30.1 (±7.8) mm and Qp/Qs 2.9 (±0.9). We observed a cubic relationship between RA volume and PSAP (r=0.354, p=0.006; Figure 1A). ASD-Diameter had a negative interaction effect (β=−0.0231 95% CI: −0.043 to −0.003, p=0.03) of the relationship between RA volume and PSAP (Figure 1B). Furthermore, the addition of Qp/Qs ratio displayed a positive triple interaction effect (β=0.021 95% CI: 0.001–0.043, p=0.048) on the previously mentioned variables (Figure 1C) after adjusting for covariates. Conclusions The increase in OS-ASD diameter and shunt decreases PSAP values. Our results could indicate that OS-ASD could potentially ameliorate chronic-volume overload in patients with secondary PH. Funding Acknowledgement Type of funding sources: None. Figure 1

Effect of interventional edge-to-edge repair in tricuspid regurgitation on ring dimensions

Abstract Background The concept of percutaneous tricuspid valve edge-to-edge repair (pTVR) is based on the connection of leaflets in the area of insufficiency using a coaptation device. By closing the coaptation device a considerable tractive force is applied on the leaflets, which might have an effect on the valve ring. Aim of the study was to examine the impact of device implantation on tricuspid ring dimensions. Methods During pTVR 3D zoom loops of tricuspid valve were acquired before and after clip placement using transoesophageal echocardiography. Measurements of TV ring dimensions included the following parameters: ring area (TV area), maximal diameter, minimal diameter, eccentricity index (Figure 1). Tenting area was derived from a four-chamber view of the valve. In addition, regurgitation severity was graded from 1+ to 5+ by measuring vena contracta area (VCA3D) in 3D full volume colour Doppler loop using multiplanar reconstruction. Right atrial (RA) and ventricular volumes (RVVd3D, RVVs3D) and function (RVEF3D) were assessed in a 3D full volume loop. Results The study population comprised 97 patients (age 78±6 years, 47 male), who underwent pTVR at our hospital. As expected cavity dimension correlated with TV area size (for RVVd3D r=0.51, p&amp;lt;0.001 and for RA volume r=0.71, p&amp;lt;0.001). The mean TV ring area was significantly reduced (ring area 8.53±2.23 cm2/m2BSA vs. 7.55±2.18 cm2/m2BSA, p&amp;lt;0.001) and the ring shape became more oval (Eccentricity index 1.2±0.15 vs. 1.29±0.17, p&amp;lt;0.001) after pTVR. The reduction of ring area (12±7%, range 0.7–28%) showed an only modest correlation to the number of implanted coaptation devices (r=0.30, p&amp;lt;0.001) and percentage reduction of VCA3D (r=0.36, p&amp;lt;0.001). In the patient group with a ring area change ≥12% a reduction to TR grade ≤2+ by pTVR was achieved in 83% of cases, whereas only 62% of patients reached moderate TR when area change was below 12%. Conclusion pTVR using coaptation devices reduces the ring area. This effect is related to the number of devices implanted. Funding Acknowledgement Type of funding sources: None.

Biatrial volume ratio predicts low voltage areas in atrial fibrillation.

BackgroundLeft atrial volume (LAV) and low voltage areas (LVAs) are acknowledged markers for worse rhythm outcome after ablation of atrial fibrillation (AF). Some studies reported the importance of increased right atrial volume (RAV) as a predictor for arrhythmia recurrences in AF patients.ObjectiveTo investigate association between the LAV/RAV ratio and LVAs presence.MethodsPatients undergoing first AF ablation were included. LVAs were assessed peri‐procedurally using high‐density 3D maps and defined as <0.5 mV. All patients underwent pre‐procedural cardiovascular magnetic resonance imaging. LAV (biplane) and RAV (monoplane 4‐chamber) were assessed prior to ablation, and the LAV/RAV ratio was calculated.ResultsThe study population included 189 patients (age mean 63 ± 10 years, 33% women, 57% persistent AF, 22% LVAs). There were 149 (79%) patients with LAV > RAV. In univariable analysis LAV > RAV was associated with LVAs (OR 6.803, 95%CI 1.395–26.514, p = .016). The association remained robust in multivariable model after adjustment for persistent AF, CHA2DS2‐VASc score, and heart rate (OR 5.981, 95%CI 1.256–28.484, p = .025). Using receiver operator curve analysis, LAV > RAV (AUC 0.668, 95%CI 0.585–0.751, p = .001) was significant predictor for LVAs. In multivariable analysis, after adjustment for age, persistent AF, and renal function, RAV≥LAV was threefold higher in males (OR 3.040, 95%CI 1.050–8.802, p = .04).ConclusionsLAV > RAV is useful for the prediction of electro‐anatomical substrate in AF. LAV > RAV was associated with LVAs presence, while male sex remained associated with RAV≥LAV and less LVAs.

Atrial structure and function in middle-aged, physically-active males and females: A cardiac magnetic resonance study.

Recent studies have reported on an association between endurance sport, atrial enlargement and the development of lone atrial fibrillation in younger, male cohorts. The atrial morphology and function of middle‐aged, physically‐active males and females have not been well studied. We hypothesized that middle‐aged males would demonstrate larger left atrium (LA) and right atrium (RA) volumes compared to females, but atrial function would not differ. LA and RA volume and function were evaluated at rest in healthy adults, using a standardized 3.0Tesla cardiac magnetic resonance protocol. Physical activity, medical history, and maximal oxygen consumption (V˙O2peak) were also assessed. Physically‐active, middle‐aged men (n = 60; 54 ± 5 years old) and women (n = 30; 54 ± 5 years old) completed this study. Males had a higher body mass index, systolic blood pressure, and V˙O2peak than females (p < .05 for all), despite similar reported physical activity levels. Absolute and BSA and height‐indexed LA and RA maximum volumes were higher in males relative to females, despite no differences in ejection fractions (p < .05 for all). In multivariable regression, male sex p < .001) and V˙O2peak (p = .004) were predictors of LA volume (model R 2 = 0.252), whereas V˙O2peak (p < .001), male sex (p = .03), and RV EF (p < .05) were predictors of RA volume (model R 2 = 0.377). While middle‐aged males exhibited larger atrial volumes relative to females, larger, prospective studies are needed to explore the magnitude of physiologic atrial remodeling and functional adaptations in relation to phenotypic factors.

Minimal fluoroscopic approaches and factors associated with radiation dose when high-definition mapping is used for supraventricular tachycardia ablation: insight from the CHARISMA registry

Abstract Funding Acknowledgements Type of funding sources: None. Background Limited data exist on factors associated with radiation exposure during ablation procedures when a high definition mapping technology is used. Purpose To report factors associated with radiation exposure and data on feasibility and safety of a minimal fluoroscopic approach using the Rhythmia mapping system in supraventricular tachycardia (SVT) ablation procedures. Methods Consecutive patients indicated for arrhythmia ablation were enrolled in the CHARISMA study at 12 centers. We included in this analysis consecutive right-side procedures performed through a minimal fluoroscopy approach with the Rhythmia mapping system were analyzed. A 3D geometry of chambers of interest was reconstructed on the basis of the electroanatomic information taken from the mapping system. Fluoroscopy was used only if deemed necessary. The effective dose (ED) was calculated using accepted formula. For our purpose high dose exposure was defined as an ED greater than the median value of ED of the population exposed to radiation. Results This analysis included 325 patients (mean age = 56 ± 17 years, 57% male) undergoing SVT procedures (152 AVNRT, 116 AFL, 41 AP and 16 AT). During the study, 27481 seconds of fluoroscopy was used (84.6 ± 224 seconds per procedure), resulting in a mean equivalent ED of 1.1 ± 3.7 mSv per patient. The mean reconstructed RA volume was 99 ± 54 ml in a mean mapping time of 12.2 ± 7 min. The mean number of radiofrequency ablations (RFC) to terminate each arrhythmia was 9.4 ± 9 (mean RFC delivery time equal to 6.7 ± 6 min). 192 procedures (59.1%) were completed without any use of fluoroscopy; during the remaining 133 procedures (39.9%), 206.6 ± 313.4 seconds of fluoroscopy was used (median ED = 1.2 mSv). In a minority of the cases (n = 25, 7.7%) the fluoroscopy time was higher than 5 minutes (median ED = 6.5 mSv), whereas radiologic exposure time greater than 1 minute occurred in ninety cases (27.7%, median ED = 2.1 mSv). On multivariate logistic analysis adjusted for baseline confounders the RFC application time (OR = 1.0014, 95%CI: 1.0007 to 1.0022; p = 0.0001) was independently associated to an ED greater than 1.2 mSv, whereas female gender had an inverse association (0.54, 0.29 to 0.98; p = 0.0435). Acute success was reached in 97.8% of the cases. During a mean of 290.7 ± 169.6 days follow-up, no major adverse events related to the procedure were reported. Overall, the recurrence rate of the primary arrhythmia during follow-up was 2.5%. Conclusions In our experience, arrhythmias ablation through minimal fluoroscopy approach with the use of a novel ablation technology is safe, feasible, and effective in common right atrial arrhythmias. High-dose exposure occurred in a very limited number of cases, without any reduction of the safety and acute and long-term effectiveness profile.

Thirty-day outcomes of the Cardioband tricuspid system for patients with symptomatic functional tricuspid regurgitation: The TriBAND study.

Severe tricuspid regurgitation (TR) has limited treatment options and is associated with high morbidity and mortality. We evaluated the safety and effectiveness of the Cardioband tricuspid valve reconstruction system from the ongoing European single-arm, multicentre, prospective TriBAND post-market clinical follow-up study. Eligible patients had chronic symptomatic functional TR despite diuretic therapy and were deemed candidates for transcatheter tricuspid repair by the local Heart Team. Sixty-one patients had ≥severe functional TR. At baseline, 85% of patients were in NYHA Class III-IV, 94% had ≥severe TR (core laboratory-assessed) with 6.8% EuroSCORE II and 53% LVEF. Device success was 96.7%. At discharge, 59% (p<0.001) of patients achieved ≤moderate TR and 78% had at least one grade TR reduction. At 30 days, all-cause mortality and composite MAE rates were 1.6% and 19.7%, respectively; septolateral annular diameter was reduced by 20%, where 69% of patients achieved ≤moderate TR and 85% of patients had at least one grade TR reduction (all p<0.001). Mid-RVEDD, RA volume, and IVC diameter decreased by 10% (p=0.005), 21% (p<0.001), and 11% (p=0.022), respectively; 74% were in NYHA Class I-II (p<0.001) with improvements in overall KCCQ score by 17 points (p<0.001). In the TriBAND study, the Cardioband tricuspid system demonstrated favourable outcomes at discharge and 30 days in a challenging patient population with symptomatic ≥severe functional TR. Results showed significant reductions in annular diameter and TR severity, accompanied by early evidence of right heart remodelling and improvements in functional status and quality of life.

Impact of right atrial structural remodeling on recurrence after ablation for atrial fibrillation.

BackgroundRecurrence of atrial fibrillation (AF) after pulmonary vein isolation (PVI) is associated with left atrial (LA) remodeling; however, its association with right atrial (RA) remodeling remains unclear.ObjectiveThis study aimed to identify whether RA structural remodeling could predict recurrence of AF after PVI.MethodsThis study prospectively analyzed 245 patients with AF who had undergone PVI. RA and LA volumes were determined by contrast‐enhanced computed tomography. Atrial structural remodeling was defined as an atrial volume of ≥110 mL according to previous reports and receiver operating characteristic curve analysis.ResultsAfter excluding 32 patients, 213 patients were analyzed. During a follow‐up period of 12 months, 41 patients (19%) demonstrated atrial arrhythmia recurrence after PVI. With the Cox proportional‐hazards model, RA structural remodeling was the only predictor of arrhythmia recurrence (hazard ratio, 1.012; 95% confidence interval 1.003‐1.021; P = .009). Kaplan–Meier analysis showed that arrhythmia recurrence was more frequent in the RA structural remodeling group compared with the group without RA remodeling (log‐rank, P < .001), and the arrhythmia‐free survival rates in these groups at 12 months were 68.0% and 91.4%, respectively. Additionally, there was a significant difference in recurrence‐free survival after RA structural remodeling in each type of AF (log‐rank, P < .001).ConclusionsRA structural remodeling is a useful predictor of clinical outcome after PVI regardless of the type of AF. Our results suggest that patients without RA structural remodeling may be good candidates for successful ablation with PVI.

Tricuspid annular dilation in patients undergoing early mitral valve surgery: is it an old story?

Patients with mitral valve prolapse (MVP), undergoing early surgery for severe regurgitation, are usually characterized by a low degree of right chambers' remodeling. In this selected population, the mechanisms leading to tricuspid annular (TA) dilatation (TAD) are not well understood. In this setting, we aimed to evaluate, using three-dimensional echocardiography (3DE), how right chambers affect TA size and might contribute to functional tricuspid regurgitation (FTR) progression. We studied 159 patients treated with early isolated surgery for MVP, characterized by: sinus rhythm; normal biventricular function; normal or elevated pulmonary artery pressure; tricuspid regurgitation (TR) ≤ mild; no concomitant cardiac disease. All patients reached a 3-year echocardiographic follow-up. Based on two-dimensional echocardiography, patients were divided in Group 1 (N = 68, 43%, TAD, TA ≥ 21mm/m2) and Group 2 (N = 91, 57%, no TAD, TA < 21mm/m2). By 3DE, Group 1 showed larger TA size, right atrial (RA) volume and right ventricular (RV) conical remodeling compared to Group 2 (p < 0.05). The multivariate analysis revealed that RA volume, RV basal diameter and function were independently correlated to TA size (p < 0.05). At the 3-year follow-up there was a low incidence of FTR, with a trend towards FTR progression in Group 1 (p = 0.07). In patients undergoing early surgery for MVP, TAD seems to result from distinctive early-onset geometrical changes of the right chambers, preceding TR, RV dilatation and pulmonary hypertension at rest. An integrated approach, including right chambers' assessment by 3DE, might help to better recognized patients at higher risk for TAD and, potentially for FTR.

Detection of severe pulmonary hypertension based on computed tomography pulmonary angiography.

Pulmonary hypertension (PH) is often diagnosed late in the disease course. As many patients may undergo computed tomography pulmonary angiography (CTPA) for exclusion of pulmonary embolism (PE), we aimed to create a model that can detect the existence of PH and grade its severity. Consecutive patients who underwent CTPA which was negative for PE, and echocardiography study within 24h, were included. The CT parameters evaluated to assess PH were: the diameters of the main pulmonary artery (MPA), ascending aorta (AA), calculation of each heart chamber volume, and the severity of reflux of contrast material. Randomly, 70% of patients were included in the model creation group, and 30% were used to validate the model. The final study group included 740 patients, 268 male patients, median age 72years. 374 patients (51%) had PH, of them 94 (13%) had severe PH on the echocardiography. Right atrium (RA) and Left atrium (LA) volume indices were the strongest parameter to indicate PH (area under the curve, AUC = 0.738 and 0.736, respectively), while Right ventricle (RV) and RA volume indices were the strongest parameter to identify severe PH (AUC = 0.735 and 0.715, respectively) with MPA diameter being the least influential indicator (AUC = 0.623). Using the patients age, gender, and multiple CTPA parameters, we created a model for predicting the existence of severe PH. After validation, the model demonstrated 91% sensitivity and a negative predictive value of 97%. Applying our models, CTPA can be used to identify severe PH immediately after the completion of CTPA exam.

Right Atrial Function Index in Chronic Thromboembolic Pulmonary Hypertension before and after Pulmonary Thromboendarterectomy

Purpose Chronic thromboembolic pulmonary hypertension (CTEPH) can be effectively treated with pulmonary thromboendarterectomy (PTE). The standard for assessing postoperative success is through right heart catheterization measurements of mean pulmonary arterial pressure (mPAP) and peripheral vascular resistance (PVR). Recently, a novel echocardiographic parameter (right atrial function index, RAFi) was shown to predict clinical outcomes in patients (pts) with precapillary PH. In this study, we assessed the utility and predictive value of this novel index in CTEPH patients before and after PTE. Methods 50 consecutive CTEPH pts with pre- and post-PTE echocardiograms (echos) were studied. RA volumes were assessed in the apical 4 chamber view. RA end-systolic volume (ESV) was measured just before tricuspid valve opening; RA end diastolic volume (EDV) was assessed at tricuspid valve closure. RV outflow tract velocity time integral (VTI) was also obtained in all pts. Calculations RAEF = ([RAESV-RAEDV]/RAESV)*100RAESVi = RAESV(mL)/BSA(m2)RAFi = (RAEF (%)*VTI (cm))/RAESVi (mL/m2) Results The mean pre-op RAFi was 24.1 ± 23.5; mean post-op RAFi was 20.2 ± 17.7 (p=0.27). Before PTE, there was a modest correlation between RAFi & mPAP (R= -0.399, p Conclusion In our patient population, RAFi was surprisingly unchanged statistically (and trended downward) after successful PTE. This trend may be due to sudden changes in RAESV and RAEDV or postoperative RV stunning, which could have caused the minimal change in RVOT VTI. Thus, RAFi cannot be used as a noninvasive parameter of post-PTE success. However, there is a significant correlation between pre-op RAFi and traditional invasive measurements that may be useful in the noninvasive assessment of pts with CTEPH.

Optimization and effect of wall conduction on natural convection in a cavity with constant temperature heat source: Using lattice Boltzmann method and neural network algorithm

In this paper, the natural convection (NC) of the Al2O3–H2O nanofluids (NFs) in a cavity with a heat source in its center is numerically investigated. A two-dimensional simulation of the cavity has been performed for this purpose. The D2Q9 LBM was used for the simulation. Then, the largest Nu was obtained using the artificial neural network (ANN). The ANN has been trained in such a way as to be able to automatically modify the input values and to estimate the largest heat transfer. With an increase in the Ra and nanoparticle volume fraction (NPVF), the heat transfer increases, but it decreases with an increase in the Ha number. In addition, the maximum heat transfer rate occurs for parallel magnetic field (MaF) and the heat transfer rate decreases with an increase in the MaF angle. As the size of the isothermal heat transfer and cold walls increase with a rise in the thermal conductivity coefficient, heat transfer also increases. With an increase in the thermal conductivity coefficient, no significant change was observed in the rate of heat transfer after an initial increase in the Nu. The largest Nu occurs at the largest Ra, largest MaF angle, and weakest MaF. The ANN predicted this value to be 7.0703, which is 2.3% different from the exact value resulting from the predicted computations.