Value of 2D speckle tracking technique combined with real-time 3-dimensional echocardiography in the evaluation of the right atrial function in patients with 3-branch coronary artery disease without myocardial infarction.

To evaluate the right atrial function in patients with 3-branch coronary artery disease (TBCAD) without myocardial infarction by 2D speckle tracking echocardiography (2D-STE) combined with real-time 3-dimensional echocardiography (RT-3DE). Fifty-six patients admitted to our hospital without myocardial infarction with TBCAD were selected. We divided them into 2 groups according to the coronary angiography results: 28 patients in group B (the rate of stenosis is 50% ~< 75%); 28 patients in group C (the rate of stenosis is ≥75%); in addition, 30 healthy volunteers were screened as group A. All subjects underwent RT-3DE to obtain the right atrial volume (RAVmax, RAVmin, and RAVp), and then we calculated the right atrial passive and active ejection fraction (RAPEF, RAAEF), and maximum volume index (RAVImax). In addition, to measure the strain rates (RASRs, RASRe, RASRa) of the right atrium during systole, early diastole, and late diastole, 2D-STE was applied. Correlations between the 2D-STE parameters and the results of N-terminal pro-brain natriuretic peptide (NT-proBNP) and Gensini scores were analyzed by Pearson linear analysis. Compared with group A, RAPEF and RASRe were reduced, while RAAEF and RASRa were elevated in group B (P < .05). RAPEF, RASRs, RASRe, and RASRa were decreased compared with groups A and B, while RAVmax, RAVmin, RAVp, RAVImax, and RAAEF were increased in group C (P < .05). There was a significant correlation between 2D-STE parameters and the results of NT-proBNP and Gensini scores (P < .05). The storage, conduit, and pump functions of the right atrium are reduced in patients with 3-branch coronary artery disease without myocardial infarction; 2D-STE combined with RT-3DE is valuable in the evaluation of the right atrium in patients with coronary artery disease.

Autonomic function and specific right atrial functions - Is there a relationship? Correlations from the three-dimensional speckle-tracking echocardiographic MAGYAR-Healthy Study.

INTRODUCTION: Similarly to the ventricles, the atria are under sympathetic/parasympathetic neural regulation. Accordingly, correlations were investigated between Ewing's standard cardiovascular reflex tests (SCRTs) and three-dimensional speckle-tracking echocardiography (3DSTE)-derived right atrial (RA) volumes and strains in healthy subjects. MATERIALS AND METHODS: The study comprised 45 healthy adults, but 5 subjects were excluded due to inferior image quality for 3DSTE-derived RA assessments. The remaining 40 individuals being in sinus rhythm had a mean age of 35.1 ± 3.5 years (20 men). Two-dimensional, Doppler, 3DSTE and SCRTs were performed in all cases. RESULTS: RA maximum volume and total and passive RA stroke volumes correlated with the Valsalva ratio. Active RA stroke volume and emptying fraction showed correlations with 30/15 ratio. Peak global and mean segmental RA circumferential (CS) and longitudinal strains (LS) showed correlation with the Valsalva ratio. At atrial contraction, global RA-LS and mean segmental RA-CS showed correlations with the Valsalva ratio. Moreover, mean segmental RA-CS correlated with 30/15 ratio and mean segmental RA radial strain showed correlations with systolic blood pressure in response to standing. Autonomic neuropathy score correlated with peak global RA-LS. CONCLUSIONS: Autonomic function parameters have significant associations with specific RA functions in healthy adults, making the latter possible indicators of autonomic dysregulation.

Elevated Left and Right Atrial Pressures Long-Term After Atrial Septal Defect Correction: An Invasive Exercise Hemodynamic Study.

Background Despite correction of the atrial septal defect (ASD), patients experience atrial fibrillation frequently and have increased morbidity and mortality. We examined physical capacity, cardiac performance, and invasive hemodynamics in patients with corrected ASD. Methods and Results Thirty-eight corrected patients with isolated secundum ASD and 19 age-matched healthy controls underwent right heart catheterization at rest and during exercise with simultaneous expired gas assessment and echocardiography. Maximum oxygen uptake was comparable between groups (ASD 32.7±7.7 mL O2/kg per minute, controls 35.2±7.5 mL O2/kg per minute, P=0.3), as was cardiac index at both rest and peak exercise. In contrast, pulmonary artery wedge v wave pressures were increased at rest and peak exercise (rest: ASD 14±4 mm Hg, controls 10±5 mm Hg, P=0.01; peak: ASD 25±9 mm Hg, controls 14±9 mm Hg, P=0.0001). The right atrial v wave pressures were increased at rest but not at peak exercise. The transmural filling pressure gradient (TMFP) was higher at peak exercise among patients with ASD (10±6 mm Hg, controls 7±3 mm Hg, P=0.03). One third of patients with ASD demonstrated an abnormal hemodynamic exercise response defined as mean pulmonary artery wedge pressure ≥25 mm Hg and/or mean pulmonary artery pressure ≥35 mm Hg at peak exercise. These patients had significantly elevated peak right and left atrial a wave pressures, right atrial v wave pressures, pulmonary artery wedge v wave pressures, and transmural filling pressure compared with both controls and patients with ASD with a normal exercise response. Conclusions Patients with corrected ASD present with elevated right and in particular left atrial pressures at rest and during exercise despite preserved peak exercise capacity. Abnormal atrial compliance and systolic atrial function could predispose to the increased long-term risk of atrial fibrillation. Registration Information clinicaltrials.gov. Identifier: NCT03565471.

Right atrium and cryptogenic ischaemic stroke in the young: a case-control study.

BACKGROUND: Recent studies suggest left atrial (LA) dysfunction in cryptogenic stroke. We studied the dynamics of right atrium (RA) and right atrial appendage (RAA) in young adults with cryptogenic stroke. We hypothesised that bi-atrial dysfunction and blood stagnation might contribute to thrombosis formation in patients with patent foramen ovale (PFO), as deep venous thrombosis is detected only in the minority of patients. METHODS: Thirty patients (aged 18-49) with a first-ever cryptogenic stroke and 30 age-matched and sex-matched stroke-free controls underwent cardiac magnetic resonance (CMR) imaging. An approach to estimate the RAA volume was developed, using crista terminalis and pectinate muscles as anatomical landmarks. Atrial expansion indices were calculated as (maximal volume - minimal volume) ×100%/minimal volume. Total pulmonary to systemic blood flow ratio (Qp/Qs) was based on phase contrast CMR. Right-to-left shunt (RLS) was evaluated with transoesophageal echocardiography in 29 patients and transcranial Doppler in 30 controls, moderate-to-severe RLS considered as clinically significant. RESULTS: We found that RA and RAA volumes were similar between patients and controls. Also, RA expansion index was similar, but RAA (95.6%±21.6% vs 108.7%±25.8%, p=0.026) and LA (126.2%±28% vs 144.9%±36.3%, p=0.023) expansion indices were lower in patients compared with controls. Seven (24%) of 29 patients had an RLS compared with 1 (3%) of 30 controls (p=0.012). Among 59 study subjects, RLS was associated with lower RA (81.9%±15.9% vs 98.5%±29.5%, p=0.030), RAA (84.7%±18% vs 105.6%±24.1%, p=0.022), LA (109.8%±18.6% vs 140.1%±33.7%, p=0.017) and LAA (median 102.9% (IQR 65.6%-121.7%) vs 229.1% (151.8%-337.5%], p=0.002) expansion indices and lower Qp/Qs ratio (0.91±0.06 vs 0.98±0.07, p=0.027). CONCLUSIONS: This study suggests bi-atrial dysfunction in young adults with cryptogenic stroke, associated with moderate-to-severe RLS. Dysfunction of the atria and atrial appendages may be an additional mechanism for PFO-related stroke. TRIAL REGISTRATION NUMBER: NCT01934725.

Left and right atrial appendage functional features as predictors for voltage-defined left atrial remodelling in patients with long-standing persistent atrial fibrillation.

It was hypothesised that left atrial (LA) fibrosis identified by the presence of low-voltage areas (LVA) may influence the mechanical and electrical function of the left (LAA) and right (RAA) atrial appendage among the long-standing persistent atrial fibrillation (LSPAF) population. 140 consecutive patients underwent voltage mapping of LA with a multielectrode catheter following pulmonary vein isolation and restoration of sinus rhythm with cardioversion. Echocardiography determined LAA peak outflow and inflow velocities and intracardiac catheter-based mean LAA and RAA AF cycle length (AFCL) were obtained during AF before ablation. The impact of flow velocities and AFCL on the prevalence and location of LVA was further evaluated. LVA were detected in 54% of the patients. 14% of the patients presented severe global LVA burden > 20% of the total LA surface area. 29% of the patients presented a disseminated pattern of remodelling as 3 out of 5 LA segments were affected. LAA AFCL, RAA AFCL, LAA flow velocities did not predict the absolute presence of LVA. However LAA AFCL > 155 ms predicted disseminated LVA pattern and LAA AFCL > 165 ms severe LVA incidence. LAA AFCL > 155 ms was predictive for existence of LVA within antero-septal LA segments whilst LAA emptying velocity ≤ 0.2 m/s within lateral wall. Moreover RAA AFCL > 165 ms was strongly related to the presence of LAA AFCL > 15 ms and > 165 ms. LAA and RAA functional assessment was predictive of the presence of advanced stages of voltage-defined LA fibrosis and its regional distribution among LSPAF population.

Cardiac Computed Tomography-Derived Left Atrial Volume Index as a Predictor of Long-Term Success of Cryo-Ablation in Patients With Atrial Fibrillation.

Patients with symptomatic, drug-refractory atrial fibrillation (AF) are frequently treated with catheter ablation. Cryo-ablation has been established as an alternative to radiofrequency ablation but long-term outcome data are still limited. This study aimed at elucidating the influence of the left atrial volume index (LAVI), derived from cardiac computed tomography (cCT) data, on the long-term outcome of ablation-naïve AF patients, after their first cryo-ablation. 415 patients (n = 290 [69.90%] male, 60.00 [IQR: 53.00 to 68.00] years old) who underwent a cCT and subsequent cryo-ablation index procedure were included in this single centre retrospective data analysis. A composite end point was defined (AF on electrocardiogram and/or electric cardioversion and/or re-do). Patients were closely followed for a year and then contacted for long-term follow-up after a median of 53.00 months (IQR: 34.50 to 73.00). Statistical analyses of the outcome and predictors of AF recurrence were conducted. In 224 patients (53.98%) no evidence of AF recurrence could be found. LAVI differed significantly between the positive and adverse (AF recurrence) outcome group (49.96 vs 56.07 ml/m2, p < 0.001). Cox regression analyses revealed cCT LAVI (HR: 1.022, 95% CI: 1.013 to 1.031, p < 0.001), BMI (HR: 1.044, 95% CI: 1.005 to 1.084, p < 0.05) and the type of AF (HR: 1.838 for nonparoxysmal AF, 95% CI: 1.214 to 2.781, p < 0.01) to be effective predictors of AF recurrence. A prognostic cCT LAVI cut-off value of 51.99 ml/m2 was calculated and must be validated in future prospective studies. In conclusion, LAVI is an accurate, yet underutilized predictor of AF recurrence after pulmonary vein isolation with cryo-energy and scores for calculating AF recurrence or progression risks might underemphasize the importance of CT-derived LAVI as a predictive factor.

International experience using a durable, centrifugal-flow ventricular assist device for biventricular support.

BACKGROUND: Heart transplantation is limited by the scarcity of suitable donors. Patients with advanced biventricular failure may require biventricular support to provide optimal cardiac output and end-organ perfusion. We highlight the outcomes of using the HeartWare HVAD System (HVAD) in a biventricular configuration. METHODS: This retrospective study included patients implanted with HVAD as a biventricular assist device (BiVAD) between 2009 and 2017 at 12 participating centers. When used as a right ventricular assist device (VAD) (RVAD), the HVAD can be attached to the right ventricle (RV) or the right atrium (RA). Kaplan-Meier survival estimates were calculated comparing the 2 RVAD implant locations. Comparisons were also made between the timing of RVAD implantation (primary vs staged) on adverse event (AE) profiles and survival. RESULTS: Among the 93 patients who were implanted with a HVAD BiVAD, Kaplan-Meier survivals at 1-year and 2-year were 56% and 47%, respectively. Survival was independent of the location of the HVAD RVAD implant or whether there was an interval between left VAD and RVAD implantation. The most common AEs were bleeding (35.5%), infection (25.8%), and respiratory failure (20.4%). CONCLUSIONS: This study illustrated similar survival in patients receiving a primary or staged HVAD BiVAD implant at 1 year and 2 years. This study also established that the locations of the RVAD implant (RV or RA) result in similar AE profiles.

Cryoballoon catheter ablation versus antiarrhythmic drugs as a first-line therapy for patients with paroxysmal atrial fibrillation: Rationale and design of the international Cryo-FIRST study.

BACKGROUND: Radiofrequency current (RFC) catheter ablation for patients with paroxysmal atrial fibrillation (AF) has been shown to be safe and effective in first-line therapy. Recent data demonstrates that RFC ablation provides better clinical outcomes compared to antiarrhythmic drug (AAD) in the treatment of early AF disease. Furthermore, studies comparing RFC and cryoballoon have established comparable efficacy and safety of pulmonary vein isolation (PVI) for patients with symptomatic paroxysmal AF. OBJECTIVES: The Cryo-FIRST trial was designed to compare AAD treatment against cryoballoon PVI as a first-line therapy in treatment naïve patients with AF. Efficacy and safety will be compared between the two cohorts and amongst subgroups. METHODS: The primary hypothesis is that cryoablation is superior to AAD therapy. To test this hypothesis, patients will be randomized in a 1:1 design. Using a 90-day blanking period, primary efficacy endpoint failure is defined as (at least) one episode of atrial arrhythmia with a duration >30 sec (documented by 7-day Holter or 12-lead ECG). Secondary endpoints (Quality-of-Life, rehospitalization, arrhythmia recurrence rate, healthcare utilization, and left atrial function) and adverse events will also be evaluated. Study enrollment will include 218 patients in up to 16 centers. CONCLUSIONS: This study will be a multi-national randomized controlled trial comparing cryoablation against AAD as a first-line treatment in patients with paroxysmal AF. The results may help guide the selection of patients for early AF disease therapy via cryoballoon ablation.

Right atrial-right ventricular coupling in heart failure with preserved ejection fraction.

BACKGROUND: Right ventricular (RV) function is prognostically relevant in heart failure with preserved ejection fraction (HFpEF) but data on profound assessment of RV and right atrial (RA) interaction in HFpEF are lacking. The current study characterizes RV and RA interaction using invasive pressure-volume-loop analysis and cardiac magnetic resonance imaging (CMR) data. METHODS AND RESULTS: We performed CMR and myocardial feature-tracking in 24 HFpEF patients and 12 patients without HFpEF. Invasive pressure-volume-loops were obtained to evaluate systolic and diastolic RV properties. RV early filling was determined from CMR RV volume-time curves. RV systolic function was slightly increased in HFpEF (RV EF 68 ± 8 vs. 60 ± 9%, p = 0.01), while no differences in RV stroke volume were found (45 ± 7 vs 42 ± 9 ml/m2, p = 0.32). RV early filling was decreased in HFpEF (21 ± 11 vs. 40 ± 11% of RV filling volume, p < 0.01) and RV early filling was the strongest predictor for VO2max even after inclusion of invasively derived RV stiffness and relaxation constant (Beta 0.63, p < 0.01). RA conduit-function was lower in HFpEF (RA conduit-strain - 11 ± 5 vs. - 16 ± 4%, p < 0.01) while RA booster-pump-function was increased (RA active-strain - 18 ± 6 vs. - 12 ± 6%, p = 0.01) as a compensation. RV filling was associated with RA conduit-function (r = - 0.55, p < 0.01) but not with invasively derived RV relaxation constant. CONCLUSION: In compensated HFpEF patients RV early filling was impaired and compensated by increased RA booster pump function, while RV systolic function was preserved. Impaired RV diastology and RA-RV interaction were linked to impaired exercise tolerance and RA-RV-coupling seems to be independent of RV relaxation, suggestive of an independent pathophysiological contribution of RA dysfunction in HFpEF. CLINICAL-TRIAL-REGISTRATION: NCT02459626 (www.clinicaltrials.gov).

Elongation of the high right atrium to coronary sinus conduction time predicts the recurrence of atrial fibrillation after radiofrequency catheter ablation.

BACKGROUND: The impact of intra-atrial conduction delay on the recurrence of atrial tachyarrhythmia after radio frequency catheter ablation (RFCA) has not been fully elucidated. METHODS: We retrospectively analyzed 155 AF patients who were sinus rhythm at the start of RFCA. The conduction time from the onset of the earliest atrial electrogram at the high right atrium (HRA) to the end of the latest electrogram at the coronary sinus (CS) during sinus rhythm was defined as HRA-CS conduction time. Pulmonary vein isolation (PVI) was performed followed by linear roof lesion and complex fractionated atrial electrogram (CFAE) ablation until AF termination. We evaluated atrial tachyarrhythmia recurrence 12 months after RFCA. RESULTS: The follow-up data were available for 148 patients. The recurrence of atrial tachyarrhythmia was noted in 28 (18.9%) patients. Atrial tachyarrhythmia recurrence patients had longer HRA-CS conduction times (151.3 ± 22.1 ms vs 160.1 ± 32.6 ms, p = .017). The patients were divided into the long or short HRA-CS conduction time group. The Kaplan-Meier analysis revealed that the long HRA-CS conduction time group held a higher risk of atrial tachyarrhythmia recurrence (log-rank test, p = .019). The multivariable Cox hazard analysis revealed that a long HRA-CS conduction time was a significant risk factor for the recurrence of atrial tachyarrhythmia, despite a long AF duration, persistent AF, and larger left atrial diameter (LAD) were not statistically significant. CONCLUSIONS: The HRA-CS conduction time was the primary influencing factor that predicted the recurrence of atrial tachyarrhythmia after catheter ablation.

Normal reference values of three-dimensional speckle-tracking echocardiography-derived right atrial volumes and volume-based functional properties in healthy adults (Insights from the MAGYAR-Healthy Study).

INTRODUCTION: The right atrium (RA) roles include being a systolic reservoir, an early diastolic conduit, and a late-diastolic booster pump. The present study aimed to assess normal reference values of three-dimensional speckle-tracking echocardiography (3DSTE)-derived RA volumetric data and volume-based functional properties in healthy adult subjects. METHODS: We included 260 healthy adult subjects in sinus rhythm with complete clinical and demographic dataset, but excluded 110 of them because of inferior image quality. The remaining population sample comprised 150 subjects (31.0 ± 11.6 years, 79 males). Complete two-dimensional Doppler echocardiography and 3DSTE have been performed in all subjects. RESULTS: Systolic RA volumetric variables did not show changes over time, but after 50 years, a significant reduction could be demonstrated in RA stroke volume and emptying fraction. While early diastolic RA volume increased over time, RA stroke volume and emptying fraction decreased. While late-diastolic RA volume increased over age decades, similar increase could be detected in RA stroke volume but a reduction occurred in older ages. Late-diastolic RA emptying fraction showed an increasing (after the 40s)-decreasing (after the 50s) pattern. CONCLUSIONS: Our study provides normal reference values of 3DSTE-derived RA volumes and volume-based functional properties and their age- and gender dependency in healthy adult subjects.

Right Ventricular Diastolic Function and Right Atrial Function and Their Relation With Exercise Capacity in Ebstein Anomaly.

BACKGROUND: Right ventricular (RV) diastolic function and right atrial (RA) function are poorly characterized in patients with Ebstein anomaly (EA) but may influence functional capacity. We aimed to evaluate RV diastolic function and RA function in EA and study their relationship with biventricular systolic function and exercise capacity. METHODS: Seventy-two patients with EA and 69 controls prospectively underwent echocardiography, cardiovascular magnetic resonance imaging, and cardiopulmonary exercise testing to investigate RV systolic and diastolic function, RA function, and exercise capacity. RESULTS: Altered RV diastolic function was indicated by the reduced tricuspid valve E/A ratio, percentage RV filling time, and early and late diastolic strain rate; and by the increased tricuspid valve E/E', isovolumic relaxation time, and RV myocardial performance index. The average of 6-RV-segment early diastolic strain rate correlated modestly with peak VO2 (r = 0.38, P < 0.01), RV ejection fraction (r = 0.41, P < 0.01), and left ventricular ejection fraction (r = 0.33, P < 0.05). Patients with EA had impaired RA reservoir, conduit, and pump function, which were associated with peak VO2 (r = 0.54, P < 0.001 for reservoir function). CONCLUSIONS: Altered RV diastolic function and RA function in patients with EA are associated with impaired biventricular systolic function and exercise capacity. The stronger correlation of RA vs RV function with exercise capacity suggests that it may be important to evaluate RA function in this population.

Invasive Hemodynamic Predictors of Renal Outcomes after Percutaneous Coronary Interventions.

OBJECTIVES: To determine the association of right heart invasive hemodynamic parameters with post-percutaneous coronary intervention (PCI) acute kidney injury (AKI). BACKGROUND: AKI after PCI is associated with a high morbidity and mortality. Various mechanisms are implicated in AKI after PCI. However, the association between filling pressures and invasive hemodynamic measures of right heart function with post-PCI AKI has not been described. METHODS: This is a retrospective single-center analysis of patients of who underwent simultaneous right heart catheterization (RHC) and left heart catheterization with PCI at the Einstein Medical Center, Philadelphia, between January 2010 and December 2016. We included patients who had hemodynamic parameters from the concomitant RHC as well as measurements of kidney function up to 1 month after the procedure. We excluded patients with ST elevation myocardial infarction, end-stage renal disease, cardiogenic shock, and PCI with a need for mechanical circulatory device support. Multivariate linear regression analysis was used to analyze the association between the various right ventricular hemodynamic parameters and eGFR within 1 week and 1 month after catheterization after adjusting for age, race, gender, diabetes and hypertension, contrast volume, cardiac index, and baseline eGFR. RESULTS: Right atrial (RA) pressure was inversely associated with eGFR within 1 week (ß = -1.66; 95% CI -3.06 to -0.25; p = 0.021) and 1 month after PCI (ß = -2.14; 95% CI -4.08 to -0.20; p = 0.031). CONCLUSION: Elevated RA pressure is associated with a worsening kidney function after cardiac catheterization and PCI.

The role of the right atrium in development of postoperative atrial fibrillation: A speckle tracking echocardiography study.

PURPOSE: Atrial fibrillation (AF) is relatively frequent in the postoperative period, and is associated with an increased frequency of adverse events. The role of right atrial (RA) volume and functions in the development of AF is unknown. In this study, we investigated the effect of RA echocardiographic indices on AF development in the postoperative period. METHOD: We enrolled 142 consecutive patients who underwent coronary artery bypass surgery, and assigned them into two groups depending on the occurrence or not of AF development in the postoperative period. RESULTS: A propensity score matching analysis was performed to balance the groups, and 37 pairs were eventually included in the analysis. The median age was 67.5 (63-75) years and 73.3% of them were males. In the univariate analysis, right atrial volume index (RAVi), right atrial strain during reservoir phase (RASr), left ventricular global longitudinal strain, right ventricular strain, left atrial volume index, left atrial strain during reservoir phase, and systolic pulmonary artery pressure were associated with AF development. In the regression analysis, we found that RAVi (OR: 3.1, 95% CI: 2.2-6.3, P: .033) and RASr (OR: 0.82, 95% CI: 0.67-0.93, P: .048) were independent predictors of AF development. CONCLUSIONS: RA structure and functions are closely associated with AF development in the postoperative period, and screening of RA functions prior to surgery may be useful for preventing AF development.

Left and Right Atrial Function and Remodeling in Beta-Thalassaemia Major.

This study aimed to assess left (LA) and right atrial (RA) function in patients with beta-thalassaemia major. Thirty-eight patients (19 males) aged 34.5 ± 10.7 years and 43 (18 males) controls aged 30.3 ± 12.6 years (p = 0.12) were studied. The maximum RA and LA areas were measured using two-dimensional planimetry, while atrial and ventricular strain and strain rates were quantified using speckle-tracking echocardiography. Compared with controls, patients had significantly reduced LA and RA peak positive strain and total strain, and LA strain rate during ventricular systole and at atrial contraction (all p < 0.05). The LA and RA strain parameters were significantly associated (all p < 0.05). The maximum LA (10.2 ± 1.6 cm2/m2 vs. 8.6 ± 1.3 cm2/m2, p < 0.001) and RA (9.2 ± 1.2 cm2/m2 vs. 7.5 ± 1.3 cm2/m2, p < 0.001) areas were significantly greater in patients than controls. The LV and RV strain and early strain rates were similar between patients and controls (all p > 0.05). Four patients with significant myocardial iron overload had larger LA area (p < 0.001) than those without. Functional and structural remodeling of both the right and left atria occurs in patients with beta-thalassaemia major, even in the absence of ventricular diastolic dysfunction.

Signal-averaged P wave area increases during respiratory events in patients with paroxysmal atrial fibrillation and obstructive sleep apnea.

PURPOSE: P wave characteristics change during simulated apneic events in individuals with atrial fibrillation (AF). This study sought to assess whether similar changes occur during nocturnal respiratory events in patients with AF and obstructive sleep apnea (OSA). METHODS: Thirty-five individuals with severe OSA who underwent formal polysomnography and subsequent AF ablation were compared to a matched group without AF. Electrocardiographic segments from each polysomnogram corresponding to the following events were identified: period of wakefulness closest to the initial onset of sleep (baseline-awake), first respiratory event, respiratory event with the lowest nadir oxygen saturation, longest respiratory event, and last respiratory event. Signal-averaged P wave duration and signal-averaged positive P wave area (amplitude*duration for positive P wave amplitudes) were extracted using custom software. P wave characteristics during respiratory events and the baseline-awake condition were compared. RESULTS: Compared to the baseline-awake condition, the signal-averaged positive P wave area was significantly greater during the longest event and the event with the lowest oxygen saturation in those with AF, but not in those without AF. There were no significant differences in signal-averaged P wave duration for any respiratory event compared to the baseline-awake condition, regardless of AF status. CONCLUSION: In patients with paroxysmal AF and obstructive sleep apnea, the signal-averaged positive P wave area is greater during certain respiratory events than during wakefulness. This finding may reflect the acute impact on right atrial volume of increased venous return associated with respiratory events and could be useful to assess AF risk in sleep apnea and to monitor response to treatment.

Impact of Increased Right Atrial Size on Long-Term Mortality in Patients With Heart Failure Receiving Cardiac Resynchronization Therapy.

The ability to visualize the right atrium (RA) by echocardiography allows a quantitative, highly reproducible assessment of the RA volume (RAV). The aim of this study is to evaluate the relation between RAV and long-term mortality in a prospective cohort of heart failure and reduced ejection fraction patients in sinus rhythm receiving cardiac resynchronization therapy. 172 patients were included. The right atrium volume index (RAVI) was calculated using Simpson's method from the apical four-chamber view and indexed to body surface area. The relation between RAVI and mortality during follow up was studied. Median follow up was 68 months (interquartile range 62 to 73 months). Mean RAVI was 27 ± 14 mL/m² (IQR 22 to 33 mL/m²). Cumulative 5-year all-cause mortality was 22 ± 6% in patients with RAVI ≤ 19 mL/m², 24 ± 6% for RAVI 19 to 29 mL/m² and 58 ± 7% for RAVI >29 mL/m² (p for trend <0.001). After adjustment on clinical and echocardiographic predictors of outcome including indices of right ventricular function, there was a significant increase in overall mortality risk with increasing RAVI (adjusted hazard ratio 1.02 [95% confidence interval, 1.00 to 1.03], per 1 mL/m2 increment; p = 0.042). Patients in the highest tertile (RAVI >29 mL/m²) had significantly greater risk of death compared with those with RAVI ≤29 mL/m² (adjusted hazard ratio 2.01 [95% confidence interval, 1.15 to 3.50]; p = 0.014). In conclusion, RA enlargement is a powerful and highly reproducible independent predictor of long-term mortality in patients with heart failure and reduced ejection fraction in sinus rhythm receiving cardiac resynchronization therapy.

Echocardiographic surrogates of right atrial pressure in pulmonary hypertension.

Right atrial pressure (RAP), a representative parameter of right heart failure, is very important for prognostic evaluation and risk assessment in pulmonary hypertension. However, its measurement requires invasive cardiac catheterization. In this study, we determined the most accurate echocardiographic surrogate of catheterization-based RAP. In 23 patients with pulmonary hypertension, a total of 66 cardiac catheterization procedures were performed along with 2-dimensional echocardiography. We evaluated tricuspid E/A, E', A' and E/E', and estimated RAP by the respirophasic variation of the inferior vena cava diameter (eRAP-IVCd) as possible surrogates of catheterization-based RAP. In simple linear regression analysis, E/A (R = 0.452, P = 0.0001) and eRAP-IVCd (R = 0.505, P < 0.0001) were positively correlated with catheterization-based RAP, whereas A' (R = - 0.512, P < 0.0001) was negatively correlated with RAP. In multiple regression analysis, A' was the most significant independent predictor of catheterization-based RAP (R = - 0.375, P = 0.0007). In 16 patients who had multiple measurements, there were a total of 43 measurements before and after medication changes. The absolute change in catheterization-based RAP was negatively correlated with the percent change in A'. Receiver operating characteristic curve analysis indicated that the optimal cut-off value of A' to predict a catheterization-based RAP > 10 mmHg was 11.3 cm/s (area under the curve = 0.782, sensitivity = 0.70, specificity = 0.78). In 20 measurements of 20 patients with left heart failure, catheterization-based RAP was not correlated with any of 5 echocardiographic parameters. However, it was closely correlated with catheterization-based pulmonary capillary wedge pressure. The echocardiographic parameter, A', was the best surrogate of catheterization-based RAP in patients with pulmonary hypertension.