Assessment of Right Atrial Function Measured with Cardiac MRI Feature Tracking for Predicting Outcomes in Patients with Dilated Cardiomyopathy.

Background Right atrial (RA) function strain is increasingly acknowledged as an important predictor of adverse events in patients with diverse cardiovascular conditions. However, the prognostic value of RA strain in patients with dilated cardiomyopathy (DCM) remains uncertain. Purpose To evaluate the prognostic value of RA strain derived from cardiac MRI (CMR) feature tracking (FT) in patients with DCM. Materials and Methods This multicenter, retrospective study included consecutive adult patients with DCM who underwent CMR between June 2010 and May 2022. RA strain parameters were obtained using CMR FT. The primary end points were sudden or cardiac death or heart transplant. Cox regression analysis was used to determine the association of variables with outcomes. Incremental prognostic value was evaluated using C indexes and likelihood ratio tests. Results A total of 526 patients with DCM (mean age, 51 years ± 15 [SD]; 381 male) were included. During a median follow-up of 41 months, 79 patients with DCM reached the primary end points. At univariable analysis, RA conduit strain was associated with the primary end points (hazard ratio [HR], 0.82 [95% CI: 0.76, 0.87]; P < .001). In multivariable Cox analysis, RA conduit strain was an independent predictor for the primary end points (HR, 0.83 [95% CI: 0.77, 0.90]; P < .001). A model combining RA conduit strain with other clinical and conventional imaging risk factors (C statistic, 0.80; likelihood ratio, 92.54) showed improved discrimination and calibration for the primary end points compared with models with clinical variables (C statistic, 0.71; likelihood ratio, 37.12; both P < .001) or clinical and imaging variables (C statistic, 0.75; likelihood ratio, 64.69; both P < .001). Conclusion CMR FT-derived RA conduit strain was an independent predictor of adverse outcomes among patients with DCM, providing incremental prognostic value when combined in a model with clinical and conventional CMR risk factors. Published under a CC BY 4.0 license. Supplemental material is available for this article.

Right Atrial Function Role in Tricuspid Regurgitation-Related Systemic Venous Congestion.

Tricuspid regurgitation (TR) is a frequent valvular pathology and when significant, may cause systemic venous congestion (SC). The right atrium (RA) is an intermediate structure between the tricuspid valve and the venous system and its role in SC is not yet defined. A total of 116 patients with a measurable TR effective regurgitant orifice area (EROA) and regurgitant volume (RVol) were selected from 2020 to 2022. SC was estimated by echocardiography using inferior vena cava diameter and estimated right atrial pressure (eRAP) and by clinical congestive features. TR grade was mild in 23 patients (20%), moderate in 53 patients (46%), and severe in 40 patients (34%). There was a significant decrease in RA function measured by strain with increasing TR severity (p <0.001). There was a marked difference in RA strain between the groups with eRAP >10 and ≤10 mm Hg (25 ± 11% vs 11 ± 7%, p <0.0001). Variables independently associated with inferior vena cava diameter were RA strain (ß -0.532, p <0.001), RA volume indexed (ß 0.249, p = 0.002), RVol (ß 0.229, p = 0.005) and EROA (ß 0.185, p = 0.016), and independently associated with eRAP >10 mm Hg were EROA (odds ratio [OR] 1.024, 95% confidence interval [CI] 1.002 to 1.046), RVol (OR 1.039, 95% CI 1.007 to 1.072) and RA strain (OR 0.863, 95% CI 0.794 to 0.940). The addition of RA strain to models containing EROA or RVol significantly improved the power of the model. RA strain was independently associated with the presence of 3 or more congestive features. In conclusion, echocardiographic and clinical signs of SC are frequent in higher degrees of TR, and RA function seems to play a key role in modulating the downstream effect of TR.

Correlation between the VExUS score and right atrial pressure: a pilot prospective observational study.

Venous congestion is an under-recognized contributor to mortality in critically ill patients. Unfortunately, venous congestion is difficult to measure, and right heart catheterization (RHC) has been considered the most readily available means for measuring venous filling pressure. Recently, a novel "Venous Excess Ultrasound (VExUS)" score was developed to noninvasively quantify venous congestion using inferior vena cava (IVC) diameter and Doppler flow through the hepatic, portal, and renal veins. A preliminary retrospective study of post-cardiac surgery patients showed promising results, including a high positive-likelihood ratio of high VExUS grade for acute kidney injury. However, studies have not been reported in broader patient populations, and the relationship between VExUS and conventional measures of venous congestion is unknown. To address these gaps, we prospectively assessed the correlation of VExUS with right atrial pressure (RAP), with comparison to inferior vena cava (IVC) diameter. Patients undergoing RHC at Denver Health Medical Center underwent VExUS examination before their procedure. VExUS grades were assigned before RHC, blinding ultrasonographers to RHC outcomes. After controlling for age, sex, and common comorbidities, we observed a significant positive association between RAP and VExUS grade (P < 0.001, R2 = .68). VExUS had a favorable AUC for prediction of a RAP ≥ 12 mmHg (0.99, 95% CI 0.96-1) compared to IVC diameter (0.79, 95% CI 0.65-0.92). These results suggest a strong correlation between VExUS and RAP in a diverse patient population, and support future studies of VExUS as a tool to assess venous congestion and guide management in a spectrum of critical illnesses.

Clinical utility and prognostic value of right atrial function in severe tricuspid regurgitation: one more piece of the puzzle.

AIMS: The optimal management of severe tricuspid regurgitation (TR) remains controversial. While right ventricular systolic function is an established prognostic marker of outcomes, the potential role of right atrial (RA) function is unknown. This study aimed to describe RA function by 2D speckle-tracking echocardiography (STE) in at least severe TR and to evaluate its potential association with cardiovascular outcomes. METHODS AND RESULTS: Consecutive patients with at least (≥) severe TR (severe, massive, or torrential TR) evaluated in the Heart Valve Clinic following a comprehensive clinical protocol were included. Consecutive control subjects and patients with permanent isolated atrial fibrillation (AF) were included for comparison (control and AF group, respectively). RA function was measured with 2D-STE and two components of RA function were calculated: reservoir (RASr) and contractile (RASct) strain (AutoStrain, Philips Medical Systems the EPIQ system). A combined endpoint of hospital admission due to heart failure (HF) or all-cause mortality was defined. Patients with ≥ severe TR (n = 140) showed lower RASr compared with controls (n = 20) and with the AF group (n = 20) (P < 0.001). Atrial TR showed lower RASr compared with other aetiologies of TR (P < 0.001). After a median follow-up of 2.2 years (IQR: 12-41 months), RASr remained an independent predictor of mortality and HF. A cut-off value of RASr of <9.4% held the best accuracy to predict outcomes. CONCLUSION: RA function by 2D-STE independently predicts mortality and HF hospitalizations in patients with ≥ severe TR.

Evaluation of right atrial function by two-dimensional echocardiography and strain imaging in patients with RCA CTO recanalization.

OBJECTIVES: The right heart is mainly supplied with blood by the right coronary artery (RCA). The impact of RCA chronic total occlusion (CTO) on the function of the right heart [right atrium (RA) and ventricle (RV)] and whether successful recanalization of a RCA CTO improves the function of the right heart is not clearly understood yet. We aimed to evaluate right atrial function after recanalization of the RCA using transthoracic echocardiography with additional strain imaging. METHODS AND RESULTS: Fifty-five patients undergoing RCA CTO recanalization at the University Medical Center of Mainz were included in the study. Right atrial strain was assessed before and 6 months after successful CTO revascularization. The median age of the total collective was 66 (50-90) years. We did not find difference in our analysis of RA Volume (p 0.086), RA area (p 0.093), RA major dimension (p 0.32) and RA minor dimension (p 0.139) at baseline and follow-up. Mean RA reservoir strain at baseline was 30.9% (21.1-43.0) vs. 33.4% (20.7-47.7) at follow up (p < 0.001). Mean RA conduit strain was - 17.5% (- 10.7-(- 29.7)) at baseline vs. - 18.2% (- 9.6-(- 31.7)) at follow-up (p = 0.346). Mean RA contraction strain was - 12.9% (- 8.0- (- 21.3)) at baseline vs. - 15.5% (- 8.7-(- 26.6)) at follow-up (p < 0.001). CONCLUSION: Right atrial function was altered in patients with RCA CTO. Successful revascularisation of an RCA CTO improved RA function assessed by strain imaging at follow-up.

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.

Prognostic value of right atrial stiffness in systemic sclerosis.

OBJECTIVES: We hypothesised that right atrial (RA) size and mechanics may have prognostic role in systemic sclerosis (SSc) patients without manifest pulmonary arterial hypertension (PAH), thus we aimed to investigate the prognostic power of RA volume, strain and stiffness parameters alone and when added to the echocardiographic marker of RV longitudinal systolic function. METHODS: Seventy SSc patients (57±12 years) were enrolled into our follow-up study. They underwent standard echocardiographic and tissue Doppler measurements at baseline. In addition to maximal RA volume index, RA reservoir, conduit and contractile strain were measured with 2D speckle tracking technique. RA stiffness was calculated as ratio of TriE/e' to reservoir strain. Survival was assessed after 5 years. All-cause mortality was chosen as outcome. Sequential χ2 analysis was used to evaluate the incremental prognostic benefit of adding RA volume, strain or stiffness to tricuspid S (TriS). RESULTS: During the follow-up period of 4.7±0.9 years, 6 patients (8.6%) died. When added to TriS in sequential Cox model, RA stiffness significantly improved the diagnostic performance of the model (Δχ2= 3.950; p=0.047) and remained independent predictor of the outcome (HR 2.460 (1.005-6.021); p=0.049). Vmax index and strain parameters did not show incremental prognostic value over TriS. Using ROC analysis, RA stiffness ≥0.156 was the best predictor of mortality (sensitivity=83.3%, specificity =89.1%, AUC=0.859). CONCLUSIONS: RA stiffness is associated with all-cause mortality in SSc patients without PAH independent of and incremental to the RV longitudinal systolic function. It may be proposed as non-invasive marker for identifying patients with high mortality risk.

Estimation of Right Atrial Pressure Using a Portable Handheld Ultrasound Device.

BACKGROUND: Handheld ultrasound devices are increasingly used by clinicians for their ease of use and portability. Their utility for estimating right atrial pressure (RAP) is poorly described. METHODS: This prospective study enrolled 50 consecutive patients presenting for outpatient right heart catheterization (RHC). A handheld ultrasound device was used to measure inferior vena cava size and collapsibility and estimate RAP to be 3, 8, or 15 mmHg according to American Society of Echocardiography recommendations for cardiac chamber quantification. Invasive pressure measurements were then performed using RHC. Spearman's correlation and linear regression analysis were used to evaluate the association between estimated RAP using ultrasound and invasive RAP. RESULTS: Fifty patients were enrolled (mean age 68 ± 8 years). Estimated RAP by ultrasound was significantly associated with invasive RAP (r 0.80; R2 0.63; 95% confidence interval, 0.61-0.96; P < .001). The correlation was stronger when RHC was indicated for evaluation of heart failure (r 0.88; P < .001) compared with other indications (r 0.69; P < .001). An estimated RAP of 3, 8, and 15 mmHg by ultrasound had a sensitivity and specificity of predicting an invasive RAP of 0-5, 6-10, and > 10 mmHg of 88% and 76%, 56% and 88%, and 81% and 97%, respectively, with overall accuracy of 80%, 76%, and 92%, respectively. Estimated RAP also correlated with invasive pulmonary capillary wedge pressure (r 0.64; R2 0.41; 95% confidence interval, 0.26-0.54; P < .001). CONCLUSIONS: Handheld ultrasonography is a useful tool that can accurately estimate RAP at the bedside.

[Application values of right atrial volume, myocardial strain and strain rate in evaluating right atrial function in patients with essential hypertension with normal left ventricular ejection fraction].

Objective: To explore the application values of right atrial (RA) volume, myocardial strain and strain rate in evaluating right atrial functions in patients with essential hypertension (EHT) with normal left ventricular ejection fraction (LVEF). Methods: We retrospectively collected a total of 126 EHT patients with normal LVEF, including 66 males and 60 females, age from 18 to 83(48±15) years from the Affiliated Changzhou No.2 People's Hospital with Nanjing Medical University from March, 2018 to May, 2020. According to the left ventricular mass index, those patients were divided into without left ventricle hypertrophy (LVH) group (n=66) and LVH group (n=60), and 83 healthy volunteers were enrolled as control group, which including 42 males and 41 females, age from 14 to 88 (48±16) years. The total, passive and active RA emptying fraction (total RAEF, passive RAEF and active RAEF) were measured by using RA volumes method. The RA strain (S-reservoir, S-conduit, S-booster pump) and the strain rate (SR-reservoir, SR-conduit, SR-booster pump) were measured by two-dimensional speckle tracking echocardiography. Total RAEF, S-reservoir, and Sr-reservoir represented the reservoir function, while passive RAEF, S-conduit, and Sr-conduit represented the conduit function, and active RAEF, S-booster pump and Sr-booster pump represented the booster pump function, respectively. Than the values between the EHT patients and normal subjects, and the values among the EHT patients without LVH, EHT patients without LVH and normal subjects were compared. Results: The value of active RAEF was significantly lower in EHT patient than normal controls (40.1%±10.5% vs 45.4%±11.1%,P=0.001). There were significant differences among EHT patients without LVH, EHT patients with LVH and normal subjects in passive RAEF and active RAEF (passive RAEF: 40.2%±9.3% vs 36.4%±10.7% vs 36.5%±9.4%, P=0.038, active RAEF: 39.8%±10.6% vs 40.4%±10.4% vs 45.4%±11.1%, P=0.002). There were significant differences in S-reservoir, S-conduit, S-booster pump, SR-reservoir, SR-conduit and SR-booster pump between EHT patients and normal subjects [S-reservoir: 34.8%±13.7% vs 45.0%±13.3%, S-conduit: 18.3%±9.4% vs 26.5%±9.6%, S-booster pump: 16.4%±7.3% vs 18.6%±7.1%, SR-reservoir: (1.6±0.6)/s vs (2.0±0.6)/s, SR-conduit: (-1.2±0.5)/s vs (-1.6±0.6)/s, SR-booster pump: (-1.7±0.6)/s vs (-2.3±0.6)/s; all P<0.05]. The trend tests showed normal controls achieved the largest the absolute values of S-reservoir, S-conduit, SR-reservoir, SR-conduit, SR-booster pump, followed by EHT patients without LVH and EHT patients with LVH(all P<0.001). Conclusions: Using RA volume, myocardial strain and strain rate can detect the RA impaired reservoir, conduit, and the booster pump functions in EHT patients with normal LVEF, and the RA functions were damaged more significantly in EHT patients with LVH.

Impaired Right Atrial Reserve Function in Heart Failure with Preserved Ejection Fraction.

BACKGROUND: Patients with heart failure with preserved ejection fraction (HFpEF) have multiple cardiac reserve limitations during exercise. However, no data are available regarding right atrial (RA) reserve capacity in HFpEF. The aim of this study was to determine the association of RA reserve impairments with right ventricular function and exercise capacity in HFpEF and to explore its diagnostic value. METHODS: Patients with HFpEF (n = 89) and control subjects without heart failure (n = 108) underwent bicycle exercise echocardiography. RA reservoir, conduit, and booster pump strain at rest and during exercise were measured using speckle-tracking echocardiography. In a subset, simultaneous expired gas analysis was performed to measure peak oxygen consumption. RESULTS: At rest, RA reservoir strain was lower in patients with HFpEF than control subjects (27.0 ± 17.1% vs 38.6 ± 17.1%, P < .0001), while RA conduit and booster pump strain were similar between groups. During peak exercise, patients with HFpEF displayed marked reserve limitations in RA reservoir and booster pump function compared with control subjects, and the differences remained significant even after adjusting for confounding factors. During peak exercise, RA reservoir and booster pump strain were correlated with right ventricular systolic function. Lower RA booster pump strain during exercise was also weakly associated with lower cardiac output (r = 0.34, P < .0001) and reduced peak oxygen consumption (r = 0.47, P < .0001). RA reservoir strain during exercise had incremental diagnostic value to differentiate patients with HFpEF from control subjects over the established HFpEF diagnostic algorithms and left-sided strain parameters. CONCLUSIONS: Limitations in RA reservoir and booster pump function during exercise are present in patients with HFpEF, and the severity is associated with right ventricular systolic reserve, poor cardiac output, and depressed exercise capacity. Exercise RA strain assessment may help in the diagnosis of HFpEF.

Evaluation of the right atrial phasic functions in patients with anterior ST-elevation myocardial infarction: a 2D speckle-tracking echocardiography study.

BACKGROUND: Evidence suggests that changes in left ventricular systolic and diastolic functions may affect right atrial (RA) phasic functions. We aimed to evaluate RA phasic functions in the presence of anterior ST-elevation myocardial infarction (ASTEMI) as an acute event and to compare the findings with those in a control group. METHODS: We recruited 92 consecutive ASTEMI patients without accompanying significant stenosis in the proximal and middle parts of the right coronary artery and 31 control subjects, matched for age, sex, diabetes, and hypertension. RA phasic functions were evaluated concerning their longitudinal 2D speckle-tracking echocardiography-derived markers. The ASTEMI group was followed up for all-cause mortality or reinfarction. RESULTS: In the ASTEMI group, RA strain was reduced during the reservoir (33.2% ± 4.3% vs 30.5% ± 8.1%; P = 0.021) and conduit (16% [12-18%] vs 14% [9-17%]; P = 0.048) phases. The other longitudinal 2D speckle-tracking echocardiography-derived markers of RA phasic functions were not different between the 2 groups. RA strain and strain rate during the contraction phase were predictive of all-cause mortality or reinfarction (hazard ratio = 0.80; P = 0.024 and hazard ratio = 0.39; P = 0.026, respectively). CONCLUSIONS: Based on 2D speckle-tracking echocardiography, in the ASTEMI group, compared with the control group, RA reservoir and conduit functions were reduced, while RA contraction function was preserved. RA contraction function was predictive of all-cause mortality or reinfarction during the follow-up period.

Right atrial phasic function and outcome in patients with heart failure and reduced ejection fraction: Insights from speckle-tracking and three-dimensional echocardiography.

BACKGROUND: Atrial phasic function can be assessed using speckle-tracking and three-dimensional (3D) echocardiography. The extent and role of right atrial (RA) dysfunction in left-sided heart failure (HF) is incompletely understood. We aimed to characterize RA phasic function in HF with reduced ejection fraction (HFrEF) and to assess its prognostic significance. METHODS: We prospectively enrolled 60 patients with HFrEF and 29 normal controls. RA phasic function was assessed using strain curves derived from speckle-tracking echocardiography and 3D volumetric analysis. Patients were followed for a composite endpoint of cardiac death or rehospitalization for HF. RESULTS: After a mean follow-up of 19 (9) months, 33 patients reached the primary endpoint. Patients with HFrEF and adverse outcomes showed an impairment of both reservoir, conduit, and booster pump RA function when compared to controls. After adjustment for age, left ventricular systolic and diastolic function, right ventricular systolic function and pulmonary artery pressure, RA maximal and minimal volumes, as well as passive emptying fraction, remained independent predictors of death or rehospitalization (hazard ratio [HR], 3.207; 95% confidence interval [CI], 1.288-7.984; P = 0.012; HR, 2.362, 95% CI, 1.004-5.552; P = 0.049; and HR, 2.367; 95% CI, 1.066-5.259; P = 0.034, respectively). CONCLUSION: All three components of RA phasic function are impaired in left-sided HF. 3D RA maximal and minimal volumes, as well as 3D RA passive emptying fraction, are independent predictors of adverse outcomes in HFrEF.

Right atrial function early after tetralogy of Fallot repair.

Diastolic dysfunction after repair for Tetralogy of Fallot (TOF) is associated with adverse long-term outcomes. Right atrial (RA) mechanics as a proxy of right ventricular (RV) diastolic function in the early post-operative period after surgical repair for TOF has not been reported. We sought to evaluate RA and RV strain prior to hospital discharge after TOF repair and to identify important patient factors associated with strain using a machine learning method. Single center retrospective cohort study of TOF patients undergoing surgical repair, with analysis of RA and RV strain from pre-and post-operative echocardiograms. RA function was assessed by the peak RA strain, systolic RA strain rate, early diastolic RA strain rate and RA emptying fraction. RV systolic function was measured by global longitudinal strain. Pre- and post-operative values were compared using Wilcoxon rank sum test. Gradient boosted machine (GBM) models were used to identify the most important predictors of post-operative strain. In total, 153 patients were enrolled, median age at TOF repair 3.5 months (25th-75th percentile: 2.2- 5.2), mostly male (67%), and White (64.1%). From pre-to post-operative period, there was significant worsening in all RA parameters and in RV strain. GBM models identified patient, anatomic, and surgical factors that were strong predictors of post-operative RA and RV strain. These factors included pulmonary valve and branch pulmonary artery Z scores, birth weight, gestational age and age at surgery, pre-operative RV fractional area change and oxygen saturation, type of outflow tract repair, duration of cardiopulmonary bypass, and early post-operative partial arterial pressure of oxygen. There is significant worsening in RA and RV strain early after TOF repair, indicating early alteration in diastolic and systolic function after surgery. Several patient and operative factors influence post-operative RV function. Most of the factors described are not readily modifiable, however they may inform pre-operative risk-stratification. The clinical application of RA strain and the prognostic implication of these early changes merit further study.

Right atrial function is associated with right venticular diastolic stiffness: RA-RV interaction in pulmonary arterial hypertension.

BACKGROUND: Pulmonary arterial hypertension (PAH) patients have altered right atrial (RA) function and right ventricular (RV) diastolic stiffness. This study assessed the impact of RV diastolic stiffness on RA-RV interaction. METHODS: PAH patients with low or high end-diastolic elastance (Eed) (n=94) were compared with controls (n=31). Treatment response was evaluated in 62 patients. RV and RA longitudinal strain, RA emptying and RV filling were determined and diastole was divided into a passive and active phase. Vena cava backflow was calculated as RA active emptying-RV active filling and RA stroke work as RA active emptying×RV end-diastolic pressure. RESULTS: With increased Eed, RA and RV passive strain were reduced while active strain was preserved. In comparison to controls, patients had lower RV passive filling but higher RA active emptying and RA stroke work. RV active filling was lower in patients with high Eed, resulting in higher vena cava backflow. Upon treatment, Eed was reduced in ~50% of the patients with high Eed, which coincided with larger reductions in afterload, RV mass and vena cava backflow and greater improvements in RV active filling and stroke volume in comparison with patients in whom Eed remained high. CONCLUSIONS: In PAH, RA function is associated with changes in RV function. Despite increased RA stroke work, severe RV diastolic stiffness is associated with reduced RV active filling and increased vena cava backflow. In 50% of patients with high baseline Eed, diastolic stiffness remained high, despite treatment. A reduction in Eed coincided with a large reduction in afterload, increased RV active filling and decreased vena cava backflow.

Atrial nitroso-redox balance and refractoriness following on-pump cardiac surgery: a randomized trial of atorvastatin.

AIMS: Systemic inflammation and increased activity of atrial NOX2-containing NADPH oxidases have been associated with the new onset of atrial fibrillation (AF) after cardiac surgery. In addition to lowering LDL-cholesterol, statins exert rapid anti-inflammatory and antioxidant effects, the clinical significance of which remains controversial. METHODS AND RESULTS: We first assessed the impact of cardiac surgery and cardiopulmonary bypass (CPB) on atrial nitroso-redox balance by measuring NO synthase (NOS) and GTP cyclohydrolase-1 (GCH-1) activity, biopterin content, and superoxide production in paired samples of the right atrial appendage obtained before (PRE) and after CPB and reperfusion (POST) in 116 patients. The effect of perioperative treatment with atorvastatin (80 mg once daily) on these parameters, blood biomarkers, and the post-operative atrial effective refractory period (AERP) was then evaluated in a randomized, double-blind, placebo-controlled study in 80 patients undergoing cardiac surgery on CPB. CPB and reperfusion led to a significant increase in atrial superoxide production (74% CI 71-76%, n = 46 paired samples, P < 0.0001) and a reduction in atrial tetrahydrobiopterin (BH4) (34% CI 33-35%, n = 36 paired samples, P < 0.01), and in GCH-1 (56% CI 55-58%, n = 26 paired samples, P < 0.001) and NOS activity (58% CI 52-67%, n = 20 paired samples, P < 0.001). Perioperative atorvastatin treatment prevented the effect of CPB and reperfusion on all parameters but had no significant effect on the postoperative right AERP, troponin release, or NT-proBNP after cardiac surgery. CONCLUSION: Perioperative statin therapy prevents post-reperfusion atrial nitroso-redox imbalance in patients undergoing on-pump cardiac surgery but has no significant impact on postoperative atrial refractoriness, perioperative myocardial injury, or markers of postoperative LV function. CLINICAL TRIAL REGISTRATION: https://clinicaltrials.gov/ct2/show/NCT01780740.

Favorable Atrial Remodeling After Percutaneous Pulmonary Valve Implantation and Its Association With Changes in Exercise Capacity and Right Ventricular Function.

Background Right atrial (RA) dilatation and impaired right ventricular (RV) filling are common in patients with RV outflow tract dysfunction. We aimed to study potential correlations between atrial function with clinically relevant hemodynamic parameters and to assess the predictive impact of atrial performance on the recovery of exercise capacity and RV pump function after percutaneous pulmonary valve implantation (PPVI). Methods and Results Altogether, 105 patients with right ventricular outflow tract dysfunction (median age at PPVI, 19.2 years; range, 6.2-53.4 years) who underwent cardiac magnetic resonance imaging before and 6 months after PPVI were included. RA and left atrial maximal and minimal volumes as well as atrial passive and active emptying function were assessed from axial cine slices. RA emptying function was inversely related to invasive RV end-diastolic pressure, and RA passive emptying correlated significantly with peak oxygen uptake. After PPVI, a significant decrease in RA minimum volume was observed, whereas RA passive emptying function improved, and RA active emptying function decreased significantly. Patients with predominant right ventricular outflow tract stenosis showed more favorable changes in RA active and left atrial passive emptying than those with primary volume overload. None of the RA and left atrial emptying parameters was predictive for recovery of peak oxygen uptake or RV ejection fraction. Conclusions In patients with right ventricular outflow tract dysfunction, impaired RA emptying assessed by cardiac magnetic resonance imaging was associated with increased RV filling pressures and lower exercise capacity. PPVI leads to a reduction in RA size and improved passive RA emptying function. However, RA function was not associated with improved exercise performance and RV pump function.

Effect of a single dose of pimobendan on right ventricular and right atrial function in 11 healthy cats.

OBJECTIVES: The objective of this study was to investigate the effect of pimobendan on echocardiographic parameters of right ventricular and atrial function in healthy cats. ANIMALS: Eleven privately owned, healthy adult cats. MATERIAL AND METHODS: Each cat underwent five echocardiographic examinations: the first and second examinations were performed 1 h apart on day 0. On day 1, the third examination served as baseline, whereas the fourth and fifth examinations were performed one and 6 h after administration of a single oral dose of pimobendan (1.25 mg/cat), respectively. Parameters of right ventricular and atrial morphology and function were collected and compared among time points. RESULTS: Pimobendan administration produced a change in some echocardiographic variables. Specifically, heart rate, right ventricular fractional shortening and peak velocity of systolic lateral tricuspid annular motion increased (P = 0.032, P = 0.002 and P < 0.001, respectively), whereas right ventricular end-systolic internal diameter and right atrial maximum and minimum internal diameters decreased (P = 0.004, P = 0.025 and P = 0.01, respectively). Right ventricular fractional area change and tricuspid annular plane systolic excursion did not change. CONCLUSIONS: This novel study showed that pimobendan had positive effects on right ventricular and right atrial function in healthy cats. Further studies are needed to determine whether pimobendan has similar effects in cats with cardiac diseases.

The impact of atrial mechanical function on age-dependent presentation of neurocardiogenic syncope.

BACKGROUND: The contribution of atrial and ventricular function in neurocardiogenic syncope (NCS) pathophysiology is elusive. HYPOTHESIS: We assessed the influence of echocardiographic properties to the age of presentation and NCS recurrences. METHODS: We assigned 124 patients with symptoms suggesting NCS, to those with syncope initiation at age <35 (group A, n = 56) and >35 years (group B, n = 68). Echocardiographic indices were measured before head-up tilt test (HUTT). RESULTS: A total of 55 had positive HUTT (44%) with a trend favoring group A (p = .08). Group A exhibited lower left atrial (LA) volume index (17 ± 6 vs. 22 ± 11 ml/m2 , p = .015), higher LA ejection fraction (69 ± 10 vs. 63 ± 11%, p = .008), LA peak strain (reservoir phase 41 ± 13 vs. 31 ± 14%, p = .001, contraction phase 27 ± 11 vs. 15 ± 10%, p < .001) and LA peak strain rate (reservoir phase 1.83 ± 1.04 vs. 1.36 ± 0.96 1/s, p = .012, conduit phase 2.36 ± 1.25 vs. 1.36 ± 0.78 1/s, p = .001). Group A showed smaller minimum right atrial (RA) volume, better RA systolic function, superior left ventricular diastolic indices, and lower filling pressures. Group A patients were more likely to have >3 recurrences (82.0% vs. 50.1%, p < .05). CONCLUSIONS: Patients with younger age of NCS onset and more syncopal recurrences manifest smaller LA and RA dimensions with distinct patterns of systolic and diastolic function and better LA reservoir and contraction properties. These findings may indicate an increased susceptibility to preload reduction, thereby triggering the NCS mechanism.

Giant right atrium, what does it hide? Case presentation.

BACKGROUND: Malformation of the right atrium is a rare cardiac abnormality and is usually reported as isolated malformation in the literature. CASE PRESENTATION: Prenatal giant atrial dilatation in an asymptomatic infant was treated surgically at 18 months of age, due to potential risk of thrombosis and arrhythmias. Post-surgical echocardiographic images illustrate residual atrial elevated pressure. CONCLUSIONS: Sometimes, as seems in our case, right atrial dilatation hides an associated restrictive right ventricle.