RV Measurements Research Articles

The Brown Dwarf Kinematics Project (BDKP). VI. Ultracool Dwarf Radial and Rotational Velocities from SDSS/APOGEE High-resolution Spectroscopy

We present precise measurements of radial (RV) and projected rotational ( vsini ) velocities of a sample of 258 M6 to L2 dwarfs with multiepoch, high-resolution (λ/Δλ = 22,500), near-infrared (1.514–1.696 μm) spectroscopic observations reported in the Apache Point Observatory Galactic Evolution Experiment Data Release 17. The spectra were modeled using a Markov Chain Monte Carlo forward-modeling method, which achieved median precisions of σ RV = 0.4 km s−1 and σvsini = 1.1 km s−1. One-half of our sample (138 sources) are previously known members of nearby young clusters and moving groups, and we identified three new kinematic members of the Argus or Carina Near moving groups, 2MASS J05402570+2448090, 2MASS J14093200+4138080, and 2MASS J21272531+5553150. Excluding these sources, we find that the majority of our sample have kinematics consistent with the Galactic thin disk, and 11 sources are associated with the intermediate thin/thick disk. The field sample has a velocity dispersion of 38.2 ± 0.3 km s−1, equivalent to an age of 3.30 ± 0.19 Gyr based on empirical age–velocity dispersion relations, and a median vsini of 17 km s−1. For 172 sources with multiepoch observations, we identified 37 as having significant RV variations, and determined preliminary orbit parameters for 26 sources with four or more epochs, nine of which are short-period binary candidates. For 40 sources with photometric variability periods from the literature less than 5 days and vsini > 20 km s−1, we find a decline in projected radii ( Rsini ) with age congruent with evolutionary models. Finally, we also present multiepoch RV and vsini measurements for additional 444 candidate ultracool dwarfs.

Long-period modulation of the classical T Tauri star CI Tau

Context. Detecting planets within protoplanetary disks around young stars is essential for understanding planet formation and evolution. However, planet detection using the radial velocity method faces challenges due to the strong stellar activity in these early stages. Aims. We detect long-term periodicities in photometric and spectroscopic time series of the classical T Tauri star (CTTS) CI Tau, and retrieve evidence for inner embedded planets in its disk. Methods. The study conducted photometric and spectroscopic analyses using K2 and Las Cumbres Observatory Global Network light curves, and high-resolution spectra from ESPaDOnS and SPIRou. We focused our radial velocity analysis on a wavelength domain less affected by spot activity. To account for spot effects, a quasi-periodic Gaussian process model was applied to K2 light curve, ESPaDOnS, and SPIRou radial velocity data. Additionally, a detailed bisector analysis on cross-correlation functions was carried out to understand the cause of long-term periodicity. Results. We detect coherent periods at ~6.6d, 9d, ~11.5d, ~14.2d, and ~25.2d, the last of which is seen consistently across all datasets. Bisector analysis of the cross-correlation functions provides strong hints for combined activity-induced and Doppler reflex signals in the radial velocities at a period of 25.2 d. Our analysis suggests that this periodicity is best explained by the presence of a 3.6 ± 0.3 MJup eccentric (e ~ 0.58) planet at a semi-major axis of 0.17 au. Conclusions. We report the detection of a massive inner planet in CI Tau. Our study outlines the difficulty of searching for disk-embedded planets in the inner 0.1 au of young and active systems. When searching for planets in actively accreting stars such as CI Tau, we demonstrate that the primary limitation is stellar activity rather than the precision of RV measurements provided by the instrument.

A novel technology for heart failure that utilizes the respiratory effort to shift fluids from the lung and alleviate cardiac workloads; feasibility study in sheep

Abstract Introduction Hemodynamic congestion is governed by inflow from RV and drainage through LV. However, ventricle functions are affected by the intrathoracic/pleural pressure: Negative pleural pressure (PPL) increases RV outflow while decreasing LV outflow, and vice versa at high PPL. Cardiac decompensation is associated with an increase in the respiratory effort (the peak-to-peak changes in PPL). We suggest to utilize this respiratory effort to shift fluid out of the lung and alleviate hemodynamic congestion. It is done by pacing the heart when PPL is high and the LV stroke volume is larger than the RV stroke volume. Purpose To test the feasibility of the novel technology in sheep. To verify that it is possible to modify the distribution of the heart beat within the respiratory cycle (slightly modify the rhythm according to the PPL) with insignificant effect on mean heart rate. Methods The utility was validated in sheep (N=9), under spontaneous breathing before and after induction of acute infarction by balloon inflation in the mid-LAD artery. The device senses the intracardiac electrical activity and respiratory effort and paces the right atrium when the PPL is high. The R-R interval of the paced beats was shorter than the sinus R-R interval by less than 10%. The effects of PPL and device pacing on LV and RV stroke-volumes were derived from simultaneous measurements of RV and LV pressure-volume loops, utilizing two impedance catheters (CD-Leycom) within both ventricles. Results The respiratory effort had significant effects on RV and LV outputs before and after infarction. The stroke volumes of the two ventricles were in antiphase! At low PPL the RV output increased while the LV decreased by about 10%, and the opposite occurred at high PPL. The pacing increased cardiac beating probability at high PPL. Sequential pacing for one minute increased the systolic pressure by 5 mmHg while decreasing the pulmonary artery pressure. Based on the pressure-volume loops, each paced breath cycle increased the LV outflow by 1.14 ml and decreased RV outflow by 0.36ml, yielding a shift of 1.5 ml from the lung. Interestingly, it was associated with a decrease in the sinus rate, which further decreased cardiac beating at low PPL and may represent a decrease in sympathetic tone. Conclusions Pacing only 1% of the ∼20,000 daily breath-cycles can shift 300 ml from the lung per day! The technology is agnostic of the heart-failure etiology. Preclinical studies in a model of chronic heart failure are required to further validate the novel approach.

Abstract 13652: Machine Learning Prediction of RV End-Diastolic Volume in Patients With Pulmonary Regurgitation

Introduction: RV end-diastolic volume (RVEDV) by cardiac MRI (cMRI) guides intervention in congenital heart disease. Guideline directed linear and area measurements from two-dimensional echocardiography (2DE) have poor univariable linear correlation with RVEDV. We hypothesized that non-linear modeling of 2DE RV measurements may predict cMRI volume. Aims: We sought to develop a prediction algorithm for RVEDV from guideline-directed RV 2DE measurements. Methods: Patients from 2009 to 2022 with > mild pulmonary regurgitation and cMRI +/- 3 months were included. 2DE measurements were: RV end-diastolic (RVED) apical 4-chamber area, basal RVED diameter (d), mid RVED d, tricuspid annulus d, RVED length; PSLAX proximal RVOT d; PSSAX proximal RVOT d, distal RVOT d. A gradient-boosting decision trees algorithm (XGBoost) regressed cMRI RVEDV (mL) using 2DE inputs (including missing data) with leave-one-out crossvalidation. Predicted RVEDV was BSA-indexed to examine performance at clinical threshold 150 mL/m 2 . Intraclass correlation coefficient (ICC) in 30 samples was measured. Results: Of 243 subjects (median age 21 [IQR 16-31] y, 58% tetralogy of Fallot, 22% congenital pulmonary stenosis s/p intervention), 19% had cMRI RVEDV > 150 mL/m 2 . Missing ranged from 5% (basal RVED d) to 17% (PSSA proximal RVOT), and ICC ranged from 0.46 (basal RVED d) to 0.78 (tricuspid annulus). Mean absolute error was 40 mL (27 mL/m 2 ). At the predicted threshold 150 mL/m 2 had 39% sensitivity, 87% specificity, 40% positive predictive value, and 86% negative predictive value for true RV dilation. Conclusion: Prediction of RVEDV from guideline recommended 2DE RV measurements is possible. Detection of clinically significant RV dilation has low sensitivity but may be helpful in ruling out cases. Sources of error include interrater variability and missing data due to poor visualization of the RV on 2DE. Future work to develop a consistent and informative feature set for modeling is required.

Kynurenine pathway metabolism evolves with development of preclinical and scleroderma-associated pulmonary arterial hypertension.

Understanding metabolic evolution underlying pulmonary arterial hypertension (PAH) development may clarify pathobiology and reveal disease-specific biomarkers. Patients with systemic sclerosis (SSc) are regularly surveilled for PAH, presenting an opportunity to examine metabolic change as disease develops in an at-risk cohort. We performed mass spectrometry-based metabolomics on longitudinal serum samples collected before and near SSc-PAH diagnosis, compared with time-matched SSc subjects without PAH, in a SSc surveillance cohort. We validated metabolic differences in a second cohort and determined metabolite-phenotype relationships. In parallel, we performed serial metabolomic and hemodynamic assessments as the disease developed in a preclinical model. For differentially expressed metabolites, we investigated corresponding gene expression in human and rodent PAH lungs. Kynurenine and its ratio to tryptophan (kyn/trp) increased over the surveillance period in patients with SSc who developed PAH. Higher kyn/trp measured two years before diagnostic right heart catheterization increased the odds of SSc-PAH diagnosis (OR 1.57, 95% CI 1.05-2.36, P = 0.028). The slope of kyn/trp rise during SSc surveillance predicted PAH development and mortality. In both clinical and experimental PAH, higher kynurenine pathway metabolites correlated with adverse pulmonary vascular and RV measurements. In human and rodent PAH lungs, expression of TDO2, which encodes tryptophan 2,3 dioxygenase (TDO), a protein that catalyzes tryptophan conversion to kynurenine, was significantly upregulated and tightly correlated with pulmonary hypertensive features. Upregulated kynurenine pathway metabolism occurs early in PAH, localizes to the lung, and may be modulated by TDO2. Kynurenine pathway metabolites may be candidate PAH biomarkers and TDO warrants exploration as a potential novel therapeutic target.NEW & NOTEWORTHY Our study shows an early increase in kynurenine pathway metabolism in at-risk subjects with systemic sclerosis who develop pulmonary arterial hypertension (PAH). We show that kynurenine pathway upregulation precedes clinical diagnosis and that this metabolic shift is associated with increased disease severity and shorter survival times. We also show that gene expression of TDO2, an enzyme that generates kynurenine from tryptophan, rises with PAH development.

Hyperspectral Infrared Observations of Arctic Snow, Sea Ice, and Non-Frozen Ocean from the RV Polarstern during the MOSAiC Expedition October 2019 to September 2020

This study highlights hyperspectral infrared observations from the Marine-Atmospheric Emitted Radiance Interferometer (M-AERI) collected as part of the Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Mobile Facility (AMF) deployment on the icebreaker RV Polarstern during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition from October 2019 to September 2020. The ARM M-AERI directly measures the infrared radiance emission spectrum between 520 cm−1 and 3000 cm−1 (19.2–3.3 μm) at 0.5 cm−1 spectral resolution. These ship-based observations provide a valuable set of radiance data for the modeling of snow/ice infrared emission as well as validation data for the assessment of satellite soundings. Remote sensing using hyperspectral infrared observations provides valuable information on sea surface properties (skin temperature and infrared emissivity), near-surface air temperature, and temperature lapse rate in the lowest kilometer. Comparison of the M-AERI observations with those from the DOE ARM meteorological tower and downlooking infrared thermometer are generally in good agreement with some notable differences. Operational satellite soundings from the NOAA-20 satellite were also assessed using ARM radiosondes launched from the RV Polarstern and measurements of the infrared snow surface emission from the M-AERI showing reasonable agreement.

How should right ventricle remodeling be assessed in women and men with chronic mitral regurgitation?

Abstract Funding Acknowledgements Type of funding sources: Public Institution(s). Main funding source(s): Haukeland University Hospital Introduction Right ventricular (RV) dysfunction has a negative impact in patients with mitral regurgitation (MR), yet its assessment by two-dimensional (2D) echocardiography remains challenging. It is unclear which echocardiographic parameter best reflects RV remodeling in chronic MR. Purpose To assess 2D and three-dimensional (3D) measures of RV size and function in relation to MR severity. Methods Patients in the 3D-PRIME (3D Echocardiography and Cardiovascular Prognosis in Mitral Regurgitation) study with moderate or severe MR by combined transthoracic/transesophageal assessment and no other severe valve disease were examined at our heart valve clinic between 2020–2022. RV remodeling was assessed in 2D by the basal diameter, tissue Doppler peak systolic velocity at the lateral tricuspid ring (RV s´), tricuspid annular plane systolic excursion (TAPSE), and RV free wall longitudinal strain (RV FWS); and in 3D by end-diastolic volume (3D RVEDV), end-systolic volume (3D RVESV), ejection fraction (3D RVEF) and fractional area change (3D RVFAC). Results 100 patients with moderate or severe MR (54 with degenerative MR; 26 with atrial functional MR; 20 with ventricular functional MR) were included. Women (n=38) had smaller MR regurgitation volumes and RV size, similar TAPSE and RV s´, but higher 3D RVEF, 3D RVFAC and RV strain normalized for 3D RVEDV (all p <0.05). More severe RV remodeling with larger volumes, and lower 3D RVFAC (all p <0.05), and 3D RVEF (p = 0.05) was detected in severe MR by 3D, but not by 2D RV measures (Figure). In ROC analyses, 3D RVESV was strongest associated with severe MR (area under curve 0.68, p <0.01, Figure). In linear regression analysis, increasing 3D RVESV was associated with higher body mass index, larger MR regurgitation volume, male sex, and larger 3D left atrial volumes (R2 0.48, p <0.001). Conclusion RV remodeling in severe MR is detected by 3D, but not by routine 2D echocardiography. The 3D RV end-systolic size best reflects MR severity.

Two warm Neptunes transiting HIP 9618 revealed by TESS and Cheops

ABSTRACT HIP 9618 (HD 12572, TOI-1471, TIC 306263608) is a bright (G = 9.0 mag) solar analogue. TESS photometry revealed the star to have two candidate planets with radii of 3.9 ± 0.044 R⊕ (HIP 9618 b) and 3.343 ± 0.039 R⊕ (HIP 9618 c). While the 20.77291 d period of HIP 9618 b was measured unambiguously, HIP 9618 c showed only two transits separated by a 680-d gap in the time series, leaving many possibilities for the period. To solve this issue, CHEOPS performed targeted photometry of period aliases to attempt to recover the true period of planet c, and successfully determined the true period to be 52.56349 d. High-resolution spectroscopy with HARPS-N, SOPHIE, and CAFE revealed a mass of 10.0 ± 3.1M⊕ for HIP 9618 b, which, according to our interior structure models, corresponds to a $6.8\pm 1.4~{{\ \rm per\ cent}}$ gas fraction. HIP 9618 c appears to have a lower mass than HIP 9618 b, with a 3-sigma upper limit of <18M⊕. Follow-up and archival RV measurements also reveal a clear long-term trend which, when combined with imaging and astrometric information, reveal a low-mass companion ($0.08^{+0.12}_{-0.05} M_\odot$) orbiting at $26.0^{+19.0}_{-11.0}$ au. This detection makes HIP 9618 one of only five bright (K < 8 mag) transiting multiplanet systems known to host a planet with P > 50 d, opening the door for the atmospheric characterization of warm (Teq < 750 K) sub-Neptunes.

The Araucaria project: High-precision orbital parallaxes and masses of binary stars

Aims. We aim to measure very precise and accurate model-independent masses and distances of detached binary stars. Precise masses at the < 1% level are necessary to test and calibrate stellar interior and evolution models, while precise and independent orbital parallaxes are essential to check for the next Gaia data releases. Methods. We combined RV measurements with interferometric observations to determine orbital and physical parameters of ten double-lined spectroscopic systems. We report new relative astrometry from VLTI/GRAVITY and, for some systems, new VLT/UVES spectra to determine the radial velocities of each component. Results. We measured the distance of ten binary systems and the mass of their components with a precision as high as 0.03% (average level 0.2%). They are combined with other stellar parameters (effective temperatures, radii, flux ratios, etc.) to fit stellar isochrones and determine their evolution stage and age. We also compared our orbital parallaxes with Gaia and showed that half of the stars are beyond 1σ with our orbital parallaxes; although, their RUWE is below the frequently used cutoff of 1.4 for reliable Gaia astrometry. By fitting the telluric features in the GRAVITY spectra, we also estimated the accuracy of the wavelength calibration to be ∼0.02% in high and medium spectral resolution modes. Conclusions. We demonstrate that combining spectroscopic and interferometric observations of binary stars provides extremely precise and accurate dynamical masses and orbital parallaxes. As they are detached binaries, they can be used as benchmark stars to calibrate stellar evolution models and test the Gaia parallaxes.

Follow-up of Young Stars Identified with BANYAN Σ: New Low-mass Members of Nearby Moving Groups

The characterization of moving groups offers a powerful means to identify large populations of young stars. In this paper, we present a sample of follow-up observations for 56 systems that have previously been proposed as members of young stellar associations through the application of the BANYAN Σ kinematic classification tool. Our measurements, which probe seven different associations, provide a sample of 39 stellar systems that either are confirmed or appear consistent with being young members of their respective associations. Nineteen of these are single M dwarfs. This sample expands our knowledge of Upper Centaurus Lupus, Coma Berenices, and AB Doradus Major to cooler temperatures and also significantly increases the known population of the Carina-Near association. The young systems present excellent targets for future planet searches and would also be valuable for studies of star formation and evolution. Additionally, we find two stellar systems that show indications of being rare instances of late-stage circumstellar accretion. Lastly, our follow-up measurements serve as a test of BANYAN Σ, finding an overall contamination rate that is consistent with previous findings (29% for systems with RV measurements, 37% without).

Right Ventricular Injury Increases Mortality in Patients With Acute Respiratory Distress Syndrome on Veno-Venous Extracorporeal Membrane Oxygenation: A Systematic Review and Meta-Analysis.

Right ventricular injury (RVI) in the context of acute respiratory distress syndrome (ARDS) is well recognized as an important determinant risk factor of mortality. Veno-venous extracorporeal membrane oxygenation (VV-ECMO) is part of the algorithm for the management of patients with severe ARDS and severely impaired gas exchange. Although VV-ECMO may theoretically protect the RV it is uncertain to what degree RVI persists despite VV-ECMO support, and whether it continues to influence mortality after ECMO initiation. The aim of this systematic review and meta-analysis was to investigate the impact of RVI on mortality in this context, testing the hypothesis that RVI worsens mortality in this cohort. We performed a systematic search that identified seven studies commenting on RVI and mortality in patients with ARDS receiving VV-ECMO. The presence of RVI was associated with greater mortality overall (odds ratios [OR]: 2.72; 95% confidence intervals [CI]: 1.52-4.85; p < 0.00) and across three subgroups (RV dilatational measures: OR: 3.51; 95% CI: 1.51-8.14; p < 0.01, RV functional measures: OR: 1.84; 95% CI: 0.99-3.42; p = 0.05, RV measurements post-ECMO initiation: OR: 1.94; 95% CI: 1.01-3.72; p < 0.05). Prospective studies are needed to investigate the causal relationship between RVI and mortality in this patient group and the best management strategies to reduce mortality.

Assessment Of Left and Right Ventricular Functions In Overweight and Obese Females by Different Echo-Doppler Modalities

Abstract Aim of work Assessment of left and right ventricular functions in overweight and obese females using different echo-Doppler modalities. Methods This study included 32 obese females (group I), 26 overweight females (group II) -both of them have no chronic illnesses- in addition to 25 healthy females (group III) as a control group. All of them had hsCRP level measured. The following parameters were measured using 2D echocardiography: LA, Ao, LA/Ao ratio, LV measures included LV dimensions, 2D LVEF, 2D LV global longitudinal strain (LVGLS), average LV Sm, Em, Am, LV E/Em ratio, LV E, A and LV E/A ratio. RV measures included LV dimensions, RV FAC, RV Tei index, TAPSE, RV Sm, Em, Am, Em/Am ratio, RV E, A, E/A ratio and PASP. Results hsCRP, LA, Ao, LV dimensions, Average LV Am, E/Em, RVD1, RV Tei and PASP were significantly higher in group I compared to group III, but group I had significantly lower LV E/A, LV Sm, Em, LVGLS, RV E/A, Em/Am and RVGLS compared to group III. Group II had significantly higher hsCRP, Ao and RV Tei and significantly lower LV E/A ratio and LV Em compared to group III. On the other hand, group, I had significantly lower average Sm, LVGLS and RVGLS than group II but no significant difference detected between two groups as regard LV and RV diastolic function. Pulse, BMI, BSA, waist circumference, waist to hip ratio, hsCRP were negatively correlated with LVGLS and RVGLS. Cut-off values for BMI showed good sensitivity and specificity to predict impaired LVGLS and RVGLS. Cut-off point 31.9 kg/m2 for impaired LVGLS with sensitivity 80%, specificity 76.81% and p value &amp;lt;0.001, cut-off point &amp;gt;30.73kg/m2 for impaired RVGLS with sensitivity 80%, specificity 69.57% and p value 0.001. Waist circumference was the most sensitive predictor for impaired LVGLS and hsCRP for impaired RVGLS. Conclusion Isolated obesity and overweight are independent predisposing factors for impaired LV and RV systolic and diastolic dysfunctions. TDI and 2D STE are good echo-Doppler modalities to detect subclinical effects on LV and RV functions. Additional Content An author video to accompany this abstract is available on https://academic.oup.com/eurheartjsupp. Please click on the arrow next to ‘More Content’ and then click on ‘Author videos’.

Right ventricular reverse remodeling after mitral valve transcatheter edge-to-edge repair

Abstract Background Right ventricular dysfunction (RVD) is an important predictor for outcome in patients undergoing transcatheter mitral or tricuspid valve edge-to-edge repair (M/T-TEER). Due to the unique anatomy and contraction pattern of the RV, three-dimensional echocardiography (3DE) has emerged as a valuable tool in the assessment of RV function. While 3DE data showed RV reverse remodeling (RVRR) following T-TEER, respective data are absent in the setting of M-TEER. Purpose We sought to assess RVRR after M-TEER using 3DE comparing baseline and follow-up RV measurements. Methods Patients undergoing M-TEER treatment for relevant MR between August 2016 and February 2021 with eligible transthoracic 3DE of the RV at baseline and follow-up were included in the study. 3DE comprised RV end-diastolic and end-systolic volumes (RVEDV3D, RVESV3D), total RV stroke volume (RVSV3D) and RV ejection fraction (RVEF3D). Further, RV length (RVL3D) as well as RV basal (RVbase3D) and mid-ventricular diameters (RVmid3D) were derived from 3DE. RVRR was assessed as change in the respective 3DE parameters of RV dimensions between baseline and follow-up. Results A total of 66 patients (45.5% female; age 78.5±8.2 years; EuroScore II 4.6±3.6%) were included in the study. From baseline to latest available follow-up (median interval 364 days, interquartile range 180–728 days), a significant reduction of RVEDV3D and RVESV3D was observed (RVEDV3D 140.2±50.2 ml to 128.1±46.1 ml, p&amp;lt;0.01 and RVESV3D 93.1±37.8ml to 87.1±34.7ml, p=0.04). The decrease in 3D-derived linear RV dimensions primarily occurred in the septolateral direction, while RV length did not change significantly. The observed RVRR was associated with significant reduction of TR severity. Of note, patients with RVRR showed also left ventricular reverse remodeling (LVRR). Conclusion M-TEER is an effective treatment option for patients with MR which leads to LVRR and RVRR. Funding Acknowledgement Type of funding sources: None.

Detailed evolutionary models for twins in sight of new spectral data: AN Cam, RS Ari, and V455 Aur

ABSTRACT We present the evolutionary scenarios for three eclipsing twin (q(M2/M1) ∼1) binary systems using their combined spectroscopic and photometric data. Using accurate TESS photometric data, RV measurements, and spectroscopic data enabled us to calculate fundamental parameters, such as mass and radius, better than 2 per cent. The temperature of each component and metallicity of the systems have been obtained via high-resolution spectra. According to our spectral analysis, the metallicity values of AN Cam, RS Ari, and V455 Aur are [M/H] = 0.00 ± 0.12, 0.05 ± 0.08, and −0.07 ± 0.07, respectively. Using the derived metallicity for each system, initial orbital parameters, and detailed evolutionary status of these three systems are calculated with high precision by using mesa. According to our analysis, both components of AN Cam have passed the terminal-age main sequence (TAMS), the primary component of RS Ari is in the giant phase while the secondary component has passed the TAMS, finally, both components of V455 Aur are still on the main sequence. The current ages of the three systems AN Cam, RS Ari, and V455 Aur are 3.0, 3.3, and 1.4 Gyr, respectively, and they will approximately start to transfer mass between components in 400, 250, and 2700 Myr, respectively.

PO-688-05 EVALUATION OF TRANSSEPTAL DELAY IN CARDIAC RESYNCHRONIZATION THERAPY PATIENTS WITH HEART FAILURE AND LEFT BUNDLE BRANCH BLOCK

Transseptal delay accounts for QRS prolongation in LBBB and may affect CRT programming. It is represented by the first notch of the QRS in Strauss-type LBBB indicating the depolarization of the LV endocardium after transiting the septum. However, little is known about the distribution of transseptal delay or the relationship with baseline electrical parameters common in CRT. To characterize transseptal delay in heart failure patients with LBBB. Heart failure patients with QRS> 120ms and Strauss-type LBBB receiving CRT, the transseptal delay (TSt) was estimated as the onset of the QRS to the peak of the first notch in at least two continuous leads (I, aVL, V1 or V6). Device-based measurements of RV and LV intrinsic activation delay (qRV/qLV) and paced inter-ventricular conduction times were evaluated for each patient. One hundred and forty-seven patients (65% Male, 32% ICM, 68 ± 10 yrs, EF 27±8%, qRV 21±11 ms, qLV 127 ± 24 ms, qLV/QRSd 0.76 ± 0.13 and QRSd 166 ± 17 ms) were evaluated. The TSt was 56 ± 14 ms (34% of QRSd; range 25 to 93 ms). There was no difference in TSt when gender (M/F) or type of cardiomyopathy (ICM/NICM) were compared. Further, correlation was poor between TSt and electrical measures during intrinsic conduction (qRV, r=0.11; qLV, r=0.08; and QRSd, r=0.22) or paced activation (RV pace to LV sense time, r=0.00 or LV pace to RV sense time, r=0.03). Transseptal delay, the basis for LV activation delay in LBBB, is widely distributed in CRT patients, not influenced by gender or type of cardiomyopathy, and unrelated to other baseline intrinsic or paced electrical parameters.

Speckle-Tracking Analysis in Fetuses With Tetralogy of Fallot: Evaluation of Right and Left Ventricular Contractility and Left Ventricular Function.

This study examines fetuses with tetralogy of Fallot (TOF) and evaluates the right (RV) and left (LV) ventricular contractility and LV function using speckle-tracking analysis of the endocardium. The study group consisted of 44 fetuses with TOF, of which 34% had pulmonary valve atresia (N=15) and 59% (N=26) had pulmonary valve stenosis. The RV and LV global fractional area change, longitudinal contractility (longitudinal strain, free wall strain, septal strain, free wall and septal annular fractional shortening, and free wall and septal wall annular plane systolic excursion), and transverse contractility (24-segment fractional shortening) as well as LV functional assessment (stroke volume, cardiac output, and ejection fraction) were measured using speckle-tracking analysis. The z-scores of the measurements were compared to 200 controls. Compared to controls, measurements of LV contractility in fetuses with TOF demonstrated significantly abnormal values for global contractility, longitudinal contractility, and transverse contractility of the mid and apical segments. LV function was abnormal for stroke volume (SV), cardiac output (CO), and ejection fraction (EF). In comparison, RV contractility demonstrated no significant difference between TOF and control z-score values for RV global contractility. Only two RV measurements were found to be abnormal: longitudinal contractility and transverse contractility of the apical segments. Using multiple measurement tools to evaluate global, longitudinal, and transverse contractility, this study identified significant differences between fetuses with TOF and healthy controls, with greater contractility abnormalities seen in the LV than in the RV.

Predictors Of Right Heart Failure Post Liver Transplant

Background Cardiac complications in liver cirrhosis are associated with increased mortality following liver transplant. Pre-transplant guidelines recommend risk stratification with 2D and dobutamine stress echocardiography, which may lead to coronary angiography or right heart catheterization. There is a paucity of data on the utility of RV hemodynamics during the perioperative period. Our objective was to determine if certain preoperative RV measurements distinguish which patients will experience post liver transplant RV failure. METHODS A retrospective study of liver transplant patients from 2015 through 2020 at the University of Cincinnati Medical Center was performed following IRB approval. Out of 389 patients, 13 had right heart failure based on ICD 10 code and discharge documentation. Preoperative echocardiographic data at baseline and peak stress were collected along with pre and postoperative RHC hemodynamics for comparison to age matched controls. Data was analyzed using two sample T tests in SPSS software. RESULTS Pre-operative RA pressure was higher in the RV failure group (12.5 vs. 6 p<0.001) and baseline PAPI was lower (1.97. vs. 3.54 p=0.02). Baseline TAPSE (2.05 vs. 2.52 p=0.03), stress TAPSE (2.75 vs. 3.22 p=0.02), and TAPSE augmentation (0.13 vs. 0.39 p=0.02) were lower in the RV failure group. Postoperatively, the RV failure group had higher RA pressure (10.01 vs. 7.46 p=0.04) and lower PAPI (1.44 vs. 3.34 p=0.004). There were no differences in mean PA and wedge pressure. The RV failure group had significantly more ventilator days (7.62 vs. 1.92 p<0.001), inotrope use (3.38 vs. 0 p<0.001), and pulmonary vasodilator use (1.93 vs. 0 p<0.001). Thirty day post-transplant mortality was 23% in the RV failure group and 0% in the control group. Data is represented in figure 1. DISCUSSION Cirrhosis causes hyperdynamic cardiac output leading to difficulty determining a pathologic level of dysfunction in these patients. Mean normal TAPSE and PAPI in the literature are 2.0cm and 2.75, respectively, but in our control group mean TAPSE was 2.52cm and PAPI was 3.54. This is likely explained by the high cardiac output state in cirrhosis. In the RV failure group, TAPSE and PAPI were within the normal range suggesting the need to identify a different baseline for patients with a hyperdynamic state due to cirrhosis. Mean PA pressure, commonly used to determine perioperative risk, did not have any discriminating ability between groups. Impaired RV reserve demonstrated by reduced TAPSE augmentation to stress may be a better predictor of RV failure in this patient population and identify patients that may be at risk for significant 30 day post-transplant mortality.

Preoperative Computed Tomography Assessment of Risk of Right Ventricle Failure After Left Ventricular Assist Device Placement.

Identification of patients who are at a high risk for right ventricular failure (RVF) after left ventricular assist device (LVAD) implantation is of critical importance. Conventional tools for predicting RVF, including two-dimensional echocardiography, right heart catheterization (RHC), and clinical parameters, generally have limited sensitivity and specificity. We retrospectively examined the ability of computed tomography (CT) ventricular volume measures to identify patients who experienced RVF after LVAD implantation. Between September 2017 and November 2021, 92 patients underwent LVAD surgery at our institution. Preoperative CT-derived ventricular volumes were obtained in 20 patients. Patients who underwent CT evaluation had a similar demographics and rate of RVF after LVAD as patients who did not undergo cardiac CT imaging. In the study cohort, seven of 20 (35%) patients experienced RVF (2 unplanned biventricular assist device, 5 prolonged inotropic support). Computed tomography-derived right ventricular end-diastolic and end-systolic volume indices were the strongest predictors of RVF compared with demographic, echocardiographic, and RHC data with areas under the receiver operating curve of 0.79 and 0.76, respectively. Computed tomography volumetric assessment of RV size can be performed in patients evaluated for LVAD treatment. RV measures of size provide a promising means of pre-LVAD assessment for postoperative RV failure.

Feasibility and role of echocontrast evaluation of patients with LVAD

Abstract Funding Acknowledgements Type of funding sources: None. Background In patients with Advanced heart failure (AHF) long-term support with durable mechanical circulatory support (MCS) devices such as left ventricular assist device (LVAD) brings survival benefits and improvement in quality of life, compared with conventional medical treatments. Development of RVF in patients with LVAD has a direct effect on mortality and is associated with prolonged length of stay in intensive care unit and in-hospital stay and with poor quality of life. Purpose: the evaluation of clinical safety and feasibility of echocontrast (EC) in patients implanted with 3 different types of LVAD (HeartWAre HVAD, Jarvik 2000, HeartMate 3); the assessment of the improvement in the visualization of heart structures; the intra and inter-operator agreement of RV measurements (FAC, TAPSE, sPAP, TR, regional wall motion abnormalities) with and without contrast. Methods: Between 2014 and 2019, 43 patients were implanted with LVAD, in particular 7 (16%) patients were implanted with Jarvik 2000, 31 (72%) with HeartMAte 3, 5 (12%) pts with HeartWAre HVAD. Nine patients (21%) either had contraindication or refused contrast injection. In 3 (7%) patients, it was technically challenging to obtain apical images at all levels. Two (5%) patients lost their follow-up. Our final population was of 29 (67%) patients. We also assessed the reproducibility of these measurements between two different expert operators (blind analysis). Results: We observed no allergic reaction to EC. Total 329 (64%) of 516 RV wall segments were available for qualitative analysis without contrast vs 451 (87%) with contrast (p &amp;lt; 0.001) with a significant improvement of the evaluability of regional contractility and FAC (41% vs 90%, p &amp;lt; 0.001). Evaluation of TAPSE, TR and sPAP was similar with and without contrast (p = NS) All the RV parameters showed little inter-operator variability when measured with contrast. TAPSE, FAC, and RWMA showed an excellent reproducibility (ICC &amp;gt;0.86) while it was good for 2D-baseline derived parameters (ICC = 0.74) showing improvement of inter operator reproducibility in the evaluation of regional contractility in the contrast echocardiography modality. Conclusion: EC is safe with all the types of LVAD we examined. Accurate and reproducible visualization of RV is imperative for reliability of information, a routine use of EC could play a pivotal role in interpreting RV features. EC improves RV morphologic and functional judgment; allowing greater accuracy and precision in the assessment of both global and regional RV functions. This finding may have important clinical improvement, especially in the future for analysis focused in RV prognostic role in LVAD patients

Abstract 10802: Validation of Artificial Intelligence for Assessing Right Ventricular Function by Transthoracic Echocardiography Compared to Cardiac MRI

Introduction: Cardiac MRI (CMR) is the gold standard for right ventricular function (RVF) because echo assessment is limited. Potential echo parameters to assess RVF include RV fractional area change (FAC), RV free wall strain (FWS), and tricuspid annular plane systolic excursion (TAPSE) on apical 4-chamber (A4C) view. We compared a new Artificial Intelligence method that tracks the RV almost instantaneously in a single 4-chamber view (AI, LVivo RV®, DiA Imaging, Figure) to quantify RVF vs CMR. Methods: We compared AI RVF against CMR in 125 pts. Abnormal LVEF and RVEF were defined as &lt;57% and &lt;49% respectively. Echo closest to CMR date was analyzed with AI RV to obtain FAC, FWS, and TAPSE. We defined abnormal RVF by DiA Imaging’s predetermined thresholds. Sensitivities and specificities for abnormal RVF and chi-square (χ 2 ) tests were calculated for each variable against CMR RVEF. Results: Of the 125 pts, 55 (44%) were female with median age 55 [Q1 44, Q3 67] years. Thirty pts (24%) had abnormal RVEF and 78 (62.4%) had abnormal LVEF by CMR. All pts with abnormal RVEF had abnormal LVEF. Compared to CMR, AI RV sensitivities and specificities for abnormal RVEF were: FAC 87% and 60%, FWS 80% and 61%, TAPSE 77% and 54%, any 2 criteria 83% and 61%, and all 3 criteria 63% and 69%. AI RV χ 2 values were: FAC 19.9 (p&lt;0.001), FWS 15.4 (p&lt;0.001), TAPSE 8.4 (p=0.004), any 2 criteria 18.0 (p&lt;0.001), and all 3 criteria 10.4 (p=0.001). Conclusions: This is the first validation of a novel AI method (LVivo RV®) that can detect RV dysfunction using 3 standard RV measurements from a single A4C view with good sensitivity and specificity compared to volumetric CMR as the gold standard.