Atrial Pressure Research Articles

Time-Dependent Association Between Agonal Respirations and Cardiopulmonary Resuscitation Hemodynamics in a Porcine Model of Cardiac Arrest

Objective: Agonal respirations (AR) are common in patients with cardiac arrest (CA) and are associated with a higher likelihood of successful return of spontaneous circulation (ROSC). Prior preclinical studies suggest that the favorable effects of AR may be mediated by improved coronary perfusion pressure (CPP) during subsequent cardiopulmonary resuscitation (CPR) efforts, but whether this relationship is influenced by the duration of CA has yet to be studied. Accordingly, we measured CPR hemodynamics in swine following 7 minutes or 10 minutes of untreated ventricular fibrillation (VF) to determine if the frequency of AR is associated with CPP after prolonged CA. Methods: Swine (n=71) were subjected to either 7 minutes (n=50) or 10 minutes (n=21) of electrically-induced VF CA, during which the frequency of AR was recorded before the initiation of CPR with chest compressions (100/minute) and mechanical ventilation (16-20 breaths/minute). CPP was assessed during CPR by calculating the difference between aortic pressure and right atrial pressure during decompression. Animals were retrospectively stratified into two groups (high and low frequency of AR) based on the median number of AR in each cohort (7-minute CA median = 6 AR; 10-minute CA median = 9 AR).>Results: In the 7-minute CA cohort, the high AR group (9.7±2.9 AR; n=28) had a significantly longer time from first to last AR (102±6 vs. 34±6 seconds; p<0.001), shorter time from final AR to CPR initiation (208±8 vs. 280±15 seconds; p<0.001), and higher CPP during CPR (14.4±1.0 vs. 9.3±0.6 mmHg; p<0.001) than the low AR group (2.9±0.4 AR; n=22). In contrast, following 10 minutes of CA, the high AR group (12.0±0.4 AR; n=11) did not have a significantly different CPP during CPR (8.7±1.8 vs. 10.4±1.5 mmHg; p=0.48) when compared to the low AR group (6.2±0.5 AR; n=10). A greater number of defibrillation attempts were required to terminate VF after 10 minutes of CA (3.0±0.6) vs. 7 minutes of CA (1.2±0.1; p<0.001), but this was not impacted by the frequency of AR in either cohort. Conclusion: Consistent with prior studies in swine subjected to 5 minutes of untreated CA, a high frequency of AR during a 7-minute episode of CA was associated with higher CPP upon initiation of CPR. However, the favorable effects of AR frequency on CPP during CPR were no longer apparent when the duration of untreated CA was extended to 10 minutes. These results demonstrate that the beneficial effects of AR on CPR hemodynamics are time-dependent and highlight the importance of early initiation of CPR following CA. Supported by funding from the NIH and US Department of Veteran's Affairs. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Allometric scaling of the parameters characterizing venous return surface in the generalized framework of circulatory equilibrium

Study objective: In the generalized framework of circulatory equilibrium (GCE), the integrated cardiac output (CO) curve characterizes the pumping abilities of the left and right hearts, whereas the venous return (VR) surface characterizes the preloading properties of the systemic and pulmonary circuits. Equilibrium CO (= VR), left (PLA) and right (PRA) atrial pressures are predicted from the intersection between the CO curve and VR surface. In VR surface, VR is theoretically related with stressed blood volume (V), PLA and PRA as: VR =V/W − Gs × PRA − Gp × PLA, where Gs and Gp is a ratio of systemic (Cs) and pulmonary (Cp) vascular compliance to W (time constant of the systemic and pulmonary circuits), respectively. However, there was a concern whether the standard parameters can be applicable to animals with different body size including human. The objective of this study is to experimentally investigate whether an allometric scaling of the parameters (Gs, Gp, W, Cs, Cp) of the VR surface is feasible. Hypothesis: Kleiber’s law indicates that an animal's metabolic rate scales to the 3⁄4 power of the animal's body weight (BW). Based on this, we hypothesize that Cs and Cp may be proportionate to BW, W may be proportionate to BW1/4. Hence, Gs and Gp may be proportionate to BW3/4. Methodology: Seven mongrel dogs (BW 26±2.8 kg) and 4 beagles (BW 9±0.5 kg) were anesthetized, and their left and right hearts were replaced by dual mechanical pumps. While V was kept constant, by controlling the speed of the fluid pumps, VR (ml/min), PLA and PRA (mmHg) were changed variably over a wide range to obtain six sets of VR, PLA and PRA. After the change of a known amount of V (4 mL/kg), six sets of VR, PLA and PRA were obtained in a similar manner. Using 12 sets of VR, PLA and PRA, we obtained Gs, Gp, W, Cs, and Cp using regression analysis in each animal. Finally, we analyzed relations between BW and all these parameters using regression analysis over the 11 animals. Data: Gs (r2=0.73, p value for independent variable piv<0.01; p value for intercept, pi=0.57) and Gp (r2=0.81, piv<0.01, pi=0.64) were proportionate to BW3/4. Cs (r2=0.37, piv=0.027, pi=0.40) and Cp (r2=0.61, piv<0.01, pi=0.48) were proportionate to BW. However, W (r2=-0.11, piv=0.90, pi=0.17) was not associated with BW1/4. Summary of results: All parameters characterizing VR surface except for W were significantly associated with BW. W did not show a significant association with BW, potentially due to the low variations of BW. Conclusions: Allometric scaling of VR surface may be feasible and effective in future clinical application of GCE. NTT Research, Inc. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Clinical usefulness of endothelial progenitor cells in predicting the efficacy of riociguat in chronic thromboembolic pulmonary hypertension.

Endothelial dysfunction is important in the pathology of pulmonary hypertension, and circulating endothelial progenitor cells (EPCs) have been studied to evaluate endothelial dysfunction. In patients with chronic thromboembolic pulmonary hypertension (CTEPH), riociguat reportedly increases the number of circulating EPCs. However, the relationship between EPC numbers at baseline and changes in clinical parameters after riociguat administration has not been fully elucidated. Here, we evaluated 27 treatment-naïve patients with CTEPH and analyzed the relationships between EPC number at diagnosis and clinical variables (age, hemodynamics, atrial blood gas parameters, brain natriuretic peptide, and exercise tolerance) before and after riociguat initiation. EPCs were defined as CD45dim CD34+ CD133+ cells and measured by flow cytometry. A low number of circulating EPCs at diagnosis was significantly correlated with increased reductions in mean pulmonary arterial pressure (mPAP) (correlation coefficient = 0.535, P = 0.004) and right atrial pressure (correlation coefficient = 0.618, P = 0.001) upon riociguat treatment. We then divided the study population into two groups according to the mPAP change: a weak-response group (a decrease in mPAP of 4 mmHg or less) and a strong-response group (a decrease in mPAP of more than 4 mmHg). The number of EPCs at diagnosis was significantly lower in the strong-response group than in the weak-response group (P = 0.022), but there were no significant differences in other clinical variables or in medication profiles. In conclusion, circulating EPC numbers could be a potential predictor of the therapeutic effect of riociguat in CTEPH patients.

An Innovative Apical-4-Chamber-long-axis Imaging Approach Precisely Tracks Progressive Deterioration of Mouse Ventricles, Atria, and Atrioventricular Valves

Transthoracic echocardiography stands as the primary non-invasive method for cardiac function evaluation in clinical settings. It’s widely used to assess chamber sizes, heart wall integrity, as well as the hemodynamic performance of the left ventricle (LV), right ventricle (RV), atria, and valves. However, applying comprehensive echocardiography assessments to mice has been challenging, primarily due to diffculties in obtaining on-axis apical 4-chamber views; most mouse studies have thus been restricted to evaluating the LV using short-axis M-mode assays. To overcome this limitation, we’ve recently developed a novel methodology to consistently obtain high-quality apical 4-chamber-long-axis (A4CLAX) view images of mouse heart. This advancement permits a range of clinically relevant functional assessments, including Long Axis Biplane (LAX-BP) assay, which has been shown to surpasses M-mode in estimating LV function. In this study, we delve into the breadth of comprehensive echocardiography assessments made possible for mice through the A4CLAX imaging approach. We performed a severe transverse aortic constriction (TAC) surgery on mice and monitored the pathological development in their hearts post-surgery. Alongside the expected hypertrophy, the LAX-BP assay revealed LV volumetric dilation as early as 1-week after TAC surgery Indicative of decompensated heart failure; however, m-mode was not able to pick up on this early dilation due to its lack of longitudinal assessment and inconsistent measurements of EDV and ESV. The apical 4 chamber view significantly improved the consistency and reliability of trans mitral and pulmonary vein doppler recordings and enabled us to reliably estimate the pressure relationships of the LV and Left Atrial (LA) pressure, which is consistent with the LAX-BP detected LV decompensation. Additionally, the high clarity of the 4 chamber images achieved improved visualization of both mitral and tricuspid valve leaflets. This allowed more precise characterization of valvular issues, including mitral regurgitation caused by LV dilatation, as well as identification of less common pathological occurrences like desynchronization of the tricuspid and mitral valve opening. A speckle tracking assay of the Right ventricle (RV) showed that a delayed contraction of the lateral apical RV wall caused the tricuspid valve to not open during the early filling phase, but rather at the atrial kick, leading to this valve desynchrony. This delayed contraction indicates a possible elevation of pulmonary pressure, as evidenced by pulmonary vein doppler indices and the analysis of pulmonary congestion. In conclusion, the innovative A4CLAX imaging technique revolutionizes murine heart analysis, bringing it in line with clinical echocardiography standards allowing for a whole heart analysis approach. It sensitively identifies subtle anomalies, providing a precise characterization of cardiac remodeling and disease progression in mouse hearts. This study has been supported by grants NIH-R01HL139006 and R21OD031965. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Increased left atrial pressure distorts pulmonary arterial impedance estimates in the low-range of frequency in rats

BACKGROUD: Post-capillary pulmonary hypertension (PH), characterized as increased downstream pressure such as left atrial pressure (LAP), is the most prevalent type of PH and a significant contributor to right heart failure. Accurate estimation of pulmonary arterial characteristics, serving as right ventricular afterload, is crucial for management of PH. These characteristics can be captured comprehensively through pulmonary arterial impedance (PAZ), which elucidates pulmonary arterial pressure-flow relationship within the frequency domain. Although LAP waveforms are potential to affect the contours of pulmonary arterial pressure (PAP) and flow (PAF) waveforms, it remains unknown whether increased LAP affects the accuracy of PAZ measurement. This study aimed to investigate the impact of LAP on the accuracy of PAZ using an acute rodent model. METHODS: We measured pulmonary arterial blood flow (PAF), PAP, and LAP simultaneously in eight male Sprague-Dawley rats. PAZ was calculated as a reciprocal of admittance. Admittance was calculated in the following two ways: 1) one-input (PAP) and one-output (PAF) analysis (I1O1 analysis): the ratio of PAP(f) to PAF(f) at each frequency, where PAP(f) and PAF(f) are frequency spectra of PAP and PAF, respectively, and 2) two-input (PAP and LAP) and one-output (PAF) analysis (I2O1 analysis): excluding the potential effect of LAP from PAP and PAF. We measured PAZ under both normal physiological condition and post-capillary PH condition. To induce acute post-capillary PH by raising LAP >15 mmHg, we ligated aortic arch at the site between brachiocephalic artery and left common carotid artery and performed blood transfusion from a donor rat (TAL/BT). The accuracy of PAZ was examined as the coherence function representing the linearity between the input and output signals. Results: TAL/BT significantly increased LAP from 3 ± 1mmHg to 21 ± 4 mmHg and PAP from 17 ± 3 mmHg to 34 ± 3 mmHg (p<0.01 for both). The I2O1 analysis provided a consistently accurate estimation of PAZ under both normal and elevated LAP conditions with high coherence function (>0.9) in the wide range of frequency between 0.12 and 10.7 Hz. The I1O1 analysis also estimated the PAZ accurately in normal condition with high coherence function (>0.9) in the wide range of frequency, however, the I1O1 analysis overestimated PAZ in the low-range frequency between 0.12 and 1.0 Hz compared with the I2O1 analysis (I1O1: 0.32±0.10 vs. I2O1 0.23±0.06 mmHg/ml/min, p<0.01), with significantly lower coherence function (I1O1: 0.77±0.05 vs. I2O1: 0.96±0.01, p<0.01). CONCLUSION: Increased LAP may have the impact on the accuracy of PAZ estimation in the low-range frequency. The I2O1 analysis can lead to more accurate assessment of right ventricular afterload in post-capillary PH, compared with the I1O1 analysis. Grant-in-Aid for Young Scientists of the Japanese Society of Cardiovascular Anesthesiologists Project Number 2271000048. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

B-57 | Change in Left Atrial Pressure on 12-month Heart Failure Outcomes After MitraClip

B-57 | Change in Left Atrial Pressure on 12-month Heart Failure Outcomes After MitraClip

Association of Renin-Angiotensin-Aldosterone System Inhibitors With Clinical Outcomes, Hemodynamics, and Myocardial Remodeling Among Patients With Advanced Heart Failure on Left Ventricular Assist Device Support.

We evaluated the potential benefits of renin-angiotensin-aldosterone system inhibitors (RAASi) in patients with left ventricular assist device support. A total of 165 consecutive patients undergoing left ventricular assist device implant and alive at 6-month on support were studied. RAASi status after 6-month visit along with clinical reasons for nonprescription/uptitration were retrospectively assessed. The primary outcome was a composite of heart failure hospitalization or cardiovascular death between 6 and 24 months after left ventricular assist device implant. Remodeling and hemodynamic outcomes were explored by studying the association of RAASi new prescription/uptitration versus unmodified therapy at 6-month visit with the change in echocardiographic parameters and hemodynamics between 6 and 18 months. After the 6-month visit, 76% of patients were on RAASi. Patients' characteristics among those receiving and not receiving RAASi were mostly similar. Of 85 (52%) patients without RAASi new prescription/uptitration at 6-month visit, 62% had no apparent clinical reason. RAASi were independently associated with the primary outcome (adjusted hazard ratio, 0.31 [95% CI, 0.16-0.69]). The baseline rates of optimal echocardiographic profile (neutral interventricular septum, mitral regurgitation less than mild, and aortic valve opening) and hemodynamic profile (cardiac index ≥2.2 L/min per m2, wedge pressure <18 mm Hg, and right atrial pressure <12 mm Hg) were similar between groups. At 18 months, patients receiving RAASi new prescription/uptitration at 6 months had higher rates of optimal hemodynamic profile (57.5% versus 37.0%; P=0.032) and trends for higher rates of optimal echocardiographic profile (39.6% versus 22.9%; P=0.055) compared with patients with 6-month unmodified therapy. Optimal 18-month hemodynamic and echocardiographic profiles were associated with the primary outcome (log-rank=0.022 and log-rank=0.035, respectively). RAASi are associated with improved outcomes and improved hemodynamics among mechanically unloaded patients.

Efficacy of Shensong Yangxin capsule combined with dronedarone in paroxysmal atrial fibrillation after ablation.

To investigate whether postoperative administration of Shensong Yangxin capsules (SSYX) and dronedarone for atrial fibrillation (AF) can reduce the recurrence of paroxysmal AF after radiofrequency ablation, thus providing a more optimal choice of antiarrhythmic medication during the blank period. We included 120 patients with paroxysmal AF who underwent radiofrequency ablation at our hospital between July 2020 and July 2022. They underwent routine circumferential pulmonary vein ablation and, subsequently, left and right atrial pressure monitoring to assess sinoatrial node recovery time under burst 400/300 ms stimulation. Postoperatively, the patients were randomly divided into 2 groups (60 patients each). The control group was administered dronedarone orally for 3 months and the study group was treated with SSYX combined with dronedarone. This study aimed to compare differences in clinical efficacy of the treatment between the 2 groups. The left and right atrial pressures in both groups were higher than those in the preoperative period (P < .05), with no statistically significant differences between the 2 groups (P > .05). Sinoatrial node recovery time under burst 400/300 ms stimulation showed no statistical difference between the 2 groups (P > .05). At 3 months and 1 year postoperatively, the AFEQT scale scores for both groups were lower than those before treatment (P < .05), with the study group scoring lower than the control group at 3 months (P < .05). However, no statistically significant difference was observed between the 2 groups at 1 year postoperatively (P > .05). At 3 months postoperatively, the sinus rhythm maintenance rate and heart rate were higher in the intervention group than in the control group (P < .05); however, these differences between the 2 groups were not statistically significant at 1 year postoperatively (P > .05). The combination of SSYX and dronedarone could effectively reduce the early recurrence of paroxysmal AF after radiofrequency ablation, increase heart rate, and improve the quality of life.

Anesthetic challenges in patients with multicompartmental lymphatic failure after Fontan palliation undergoing transcatheter thoracic duct decompression.

Lymphatic flow abnormalities are central to the development of protein losing enteropathy, plastic bronchitis, ascites and pleural effusions in patients palliated to the Fontan circulation. These complications can occur in isolation or multicompartmental (two or more). The treatment of multicompartmental lymphatic failure aims at improving thoracic duct drainage. Re-routing the innominate vein to the pulmonary venous atrium decompresses the thoracic duct, as atrial pressure is lower than systemic venous pressure in Fontan circulation. Transcatheter thoracic duct decompression is a new minimally invasive procedure that involves placing covered stents from the innominate vein to the atrium. Patients undergoing this procedure require multiple general anesthetics, presenting challenges in managing the sequelae of disordered lymphatic flow superimposed on Fontan physiology. We reviewed the first 20 patients at the Center for Lymphatic Imaging and Intervention at a tertiary care children's hospital presenting for transcatheter thoracic duct decompression between March 2018 and February 2023. The patients ranged in age from 3 to 26 years. The majority had failed prior catheter-based lymphatic intervention, including selective embolization of abnormal lympho-intestinal and lympho-bronchial connections to treat lymphatic failure in a single compartment. Fourteen had failure in three lymphatic compartments. Patients were functionally impaired (ASA 3-5) with significant comorbidities. Concurrent with thoracic duct decompression, three patients required fenestration closure for the resultant decrease in oxygen saturation. Ten patients had improvement in symptoms, seven had no changes and three have limited follow up. Five (25%) of these patients were deceased as of January 2024 due to non-lymphatic complications from Fontan failure.

Macitentan in Adults with Sickle Cell Disease and Pulmonary Hypertension: A Proof-of-Concept Study

Pulmonary hypertension (PH) in sickle cell disease (SCD) is associated with a mortality rate of 37%. There is an upregulation of adhesion molecules which leads to the expression of endothelin-1, a potent vasoconstrictor. A prospective, descriptive study was done to determine the safety and efficacy of macitentan in patients with SCD and PH. Continuous variables were reported as mean ± SEM or percentage where appropriate. We screened 13 patients and recruited five. All five patients were adults. Data were analyzed as appropriate by student t - test. Statistical significance was assumed at p &lt; 0.05. Baseline pulmonary hemodynamics obtained by right heart catheterization and systemic hemodynamics were (± SEM): mean pulmonary artery pressure (MPAP) 32 ± 8 mmHg, right atrial pressure (RAP) 9 ± 4 mmHg, pulmonary vascular resistance (PVR) 257 dynes-sec/cm5 and CI 3·7 ± 0.39 l/m2. Of all parameters, only PVR and 6-min walk distance changed significantly. For the group, MPAP decreased by 15.6%, PVR by 22.5% and RAP by 25.5%. The 6-minute walk distance increased over sixteen weeks except in Patient 4 who had a 3% decrease. The mean walk distance increased in the total distance, from 464 ± 158 meters to 477 ± 190 meters (p .123). In four patients, the adverse events were mild to moderate and did not lead to study drug discontinuation. Significant improvement in pulmonary hemodynamics and exercise capacity in patients with SCD-related pulmonary arterial hypertension. We found that macitentan was safe and well tolerated.

Prognostic role of haemodynamics at follow-up in patients with pulmonary arterial hypertension: a challenge to current European Society of Cardiology/European Respiratory Society risk tools.

Haemodynamic variables like right atrial pressure (RAP), cardiac index (CI), stroke volume index (SVI) and mixed venous oxygen saturation (S vO2 ) predict survival in patients with pulmonary arterial hypertension (PAH). However, there is the need to identify further prognostic haemodynamic parameters as well as to redefine their role in PAH risk stratification compared to current risk tools and non-invasive parameters. This cohort study includes treatment-naïve patients assessed at baseline and after first-line PAH therapy with clinical, functional, exercise, laboratory and haemodynamic evaluations. Using a stepwise multivariate Cox regression analysis, independent prognostic haemodynamic parameters were identified and stratified according to cut-offs already defined in the European Society of Cardiology (ESC)/European Respiratory Society (ERS) risk table or defined based on the highest Chi-squared of the log-rank test. Their discriminatory power was tested for all-cause death and a combined end-point of death, hospitalisation and need of treatment escalation. 794 patients with PAH were enrolled. At first follow-up, RAP and pulmonary artery elastance were independently associated with death. Because of high correlations between haemodynamic parameters, different multivariable analyses were done identifying six other variables (pulmonary arterial compliance, cardiac efficiency, pulmonary vascular resistance, S vO2 , CI and SVI). Haemodynamic parameters were of no added prognostic value compared to ESC/ERS risk tools for the all-cause death end-point but they showed additional value to non-invasive parameters for the combined end-point and, when taken alone, had a discriminatory capacity comparable to ESC/ERS risk tools. Haemodynamics' discriminative ability for clinical worsening is comparable to current ESC/ERS risk tools and is of added value to non-invasive parameters.

Atrial Shunt Device Effects on Cardiac Structure and Function in Heart Failure With Preserved Ejection Fraction

Although the results of A Study to Evaluate the Corvia Medical Inc IASD System II to Reduce Elevated Left Atrial Pressure in Patients with Heart Failure (REDUCE LAP-HF II) trial were neutral overall, atrial shunt therapy demonstrated potential efficacy in responders (no latent pulmonary vascular disease and no cardiac rhythm management device). Post hoc analyses were conducted to evaluate the effect of shunt vs sham stratified by responder status. To evaluate the effect of atrial shunt vs sham control on cardiac structure/function in the overall study and stratified by responder status. This was a sham-controlled randomized clinical trial of an atrial shunt device in heart failure with preserved ejection fraction (HFpEF)/HF with mildly reduced EF (HFmrEF). Trial participants with evaluable echocardiography scans were recruited from 89 international medical centers. Data were analyzed from April 2023 to January 2024. Atrial shunt device or sham control. Changes in echocardiographic measures from baseline to 1, 6, 12, and 24 months after index procedure. The modified intention-to-treat analysis of the REDUCE LAP-HF II trial included 621 randomized patients (median [IQR] age, 72.0 [66.0-77.0] years; 382 female [61.5%]; shunt arm, 309 [49.8%]; sham control arm, 312 [50.2%]). Through 24 months, 212 of 217 patients (98%) in the shunt arm with evaluable echocardiograms had patent shunts. In the overall trial population, the shunt reduced left ventricular (LV) end-diastolic volume (mean difference, -5.65 mL; P <.001), left atrial (LA) minimal volume (mean difference, -2.8 mL; P =.01), and improved LV systolic tissue Doppler velocity (mean difference, 0.69 cm/s; P <.001) and LA emptying fraction (mean difference, 1.88 percentage units; P =.02) compared with sham. Shunt treatment also increased right ventricular (RV; mean difference, 9.58 mL; P <.001) and right atrial (RA; mean difference, 9.71 mL; P <.001) volumes but had no effect on RV systolic function, pulmonary artery pressure, or RA pressure compared with sham. In the shunt arm, responders had smaller increases in RV end-diastolic volume (mean difference, 5.71 mL vs 15.18 mL; interaction P =.01), RV end-systolic volume (mean difference, 1.58 mL vs 7.89 mL; interaction P =.002), and RV/LV ratio (mean difference, 0.07 vs 0.20; interaction P <.001) and larger increases in transmitral A wave velocity (mean difference, 5.08 cm/s vs -1.97 cm/s; interaction P =.02) compared with nonresponders randomized to the shunt, suggesting greater ability to accommodate shunted blood through the pulmonary circulation enabling LA unloading. In this post hoc analysis of the REDUCE LAP-HF II trial, over 2 years of follow-up, atrial shunting led to reverse remodeling of left-sided chambers and increases in volume of right-sided chambers consistent with the shunt flow but no change in RV systolic function compared with sham. Changes in cardiac structure/function were more favorable in responders compared with nonresponders treated with the shunt, supporting the previously identified responder group hypothesis and mechanism, although further evaluation with longer follow-up is needed. ClinicalTrials.gov Identifier: NCT03088033.

Prevalence and Predictors of Readmissions in Patients With Hypertrophic Cardiomyopathy and Atrial Fibrillation/Flutter

Atrial fibrillation/flutter (AF) is the most common dysrhythmia in patients with hypertrophic cardiomyopathy (HCM). Unexplained left ventricular hypertrophy and left ventricular outflow tract obstruction are integral components of HCM pathology which can cause increased left atrial pressure and atrial myopathy contributing to the substrate for AF. We aimed to determine the impact of AF on hospital readmissions in patients with HCM. We conducted a retrospective analysis using the 2015 to 2019 Nationwide Readmission Database to analyze the effect of AF on 30-day readmission and causes of 30-day readmission in patients with HCM. We also determined the hospital, patient, and procedure-specific independent predictors of readmission in patients with HCM and AF. Of 191,235 index HCM hospitalizations, 81,390 (42.6%) had a secondary diagnosis of AF. A total of 16.9% of patients with HCM and AF were readmitted within 30 days as compared with 14% of HCM patients without AF. The presence of AF was independently associated with a higher risk of all-cause 30-day readmission (hazard ratio [HR] 1.21, 95% confidence interval [CI] 1.17 to 1.25, p <0.001). The foremost etiology of 30-day readmission in HCM patients with AF was hypertensive heart and chronic kidney disease with heart failure, whereas the foremost etiology of 30-day readmission in HCM patients without AF was sepsis. Interventions aimed toward AF management (electrical cardioversion: adjusted HR 0.91, 95% CI 0.82 to 1.01. p = 0.074, AF ablation: HR 0.92, 95% CI 0.74 to 1.13, p = 0.409, Watchman procedure: HR 1.50, 95% CI 0.16 to 14.6, p = 0.725) during index admission did not significantly impact the 30-day readmission in HCM patients with AF. Myectomy during index hospitalization (adjusted HR 0.54, 95% CI 0.34 to 0.86, p = 0.010) was most strongly associated with a lower risk of 30-day readmission in HCM patients with AF. In conclusion, in patients hospitalized for HCM, presence of AF was associated with excess risk of 30-day all-cause readmission. Interventions aimed toward HCM management, that is, myectomy rather than interventions aimed toward AF management predicted lower readmission rate in this patient population.

Late Presentation of Pulmonary Hypertension Crisis Concurrent with Atrial Arrhythmia after Atrial Septal Defect Device Closure

Background: ASD occurs when there is a septal defect between the right and left atria, resulting in a left-to-right shunt that increases the volume of the right heart and pulmonary circulation. Increased pulmonary resistance can lead to pulmonary hypertension (PH), resulting in progressive deterioration of right ventricular function, leading to right heart failure and death. Prolonged elevation of atrial pressure induces progressive atrial dilatation and electrophysiological remodelling. Together with autonomic modulation, this leads to atrial arrhythmias (AAs). Patients with significant shunts leading to ventricular volume overload are considered for ASD closure. However, in some cases, PH occurs after ASD closure.  Case Presentation: We report a 21 yo man diagnosed with ASD Secundum Post Closure with Device (September 1th, 2023) and Pulmonary Hypertension Crisis. The left atria (LA), right atria (RA) and right ventricle (RV) were dilated. We also found moderate mitral regurgitation, severe tricuspid regurgitation, and mild to moderate pulmonary regurgitation. There was a decline in systolic function in the right ventricle, and grade III diastolic dysfunction in left ventricle. There was a well-seated device with no residual shunt on interatrial septal. The pulmonary arteries were confluence and dilated. From ECG we found atrial flutter with variable conduction. This patient was transferred to HCU. This patient treated with digoxin, furosemide, milrinon, ceftriaxone, miniaspi, sildenafil, electrophysiology, and 3D ablation.  Conclusion: Pulmonary hypertension can occur in cases of congenital heart defects, such as ASD. The operative management of ASD is closure of the ASD, but in some unique groups, this can lead to pulmonary hypertensive crisis after its closure.

Sudden death due to spontaneous rupture of the right atrium in the setting of chronic lung disease: A case report and review.

Sudden death from haemopericardium as a result of a right atrial rupture is uncommon, most particularly when this occurs spontaneously without any prior trauma or evidence of atrial wall pathology. The deceased was a 32-year-old man. At lunchtime his symptoms of unease, giddiness and unconsciousness began and within 45 minutes he arrived at the hospital. His vitals could not be recorded in the emergency department, and after CPR, he was pronounced dead. At autopsy, an isolated right atrial rupture, without any disease of the heart wall, was discovered. The right atrium has the weakest wall and is frequently the site of spontaneous rupture brought on by increased intraluminal pressure. Both liquid blood and clotted blood were found in the pericardial cavity. Low atrial pressure encourages clot formation because it causes considerably slower blood entry into the pericardium at the time of atrial rupture compared with entry at the time of ventricular rupture. Evidence of chronic lung disease was found which explains the raised intraluminal pressure of the heart chambers. Even with no history of trauma or myocardial infarction, the Beck triad - an engorged neck vein, a muffled heart sound, and low blood pressure - should alert the emergency room staff to the possibility of cardiac tamponade because, in a very unlikely scenario, spontaneous cardial wall rupture might occur.

Serum PM20D1 levels in patients with idiopathic pulmonary arterial hypertension and its clinical significance

ObjectiveThis study aimed to investigate the serum levels of Peptidase M20 domain containing 1 (PM20D1) in idiopathic pulmonary arterial hypertension (IPAH) patients and examine its association with lipid metabolism, echocardiography, and hemodynamic parameters.MethodsThis prospective observational research enrolled 103 IPAH patients from January 2018 to January 2022. Enzyme-linked immunosorbent assay (ELISA) was used to measure the serum PM20D1 levels in all patients before treatment within 24 h of admission. Demographic data, echocardiography, hemodynamic parameters and serum biomarkers were also collected.ResultsThe IPAH patients in the deceased group had significantly elevated age, right atrial (RA), mean pulmonary arterial pressure (mPAP), mean right atrial pressure (mRAP), pulmonary capillary wedge pressure (PCWP), pulmonary vascular resistance (PVR) and significantly decreased 6 min walking distance (6MWD) and tricuspid annulus peak systolic velocity (TASPV). IPAH patients showed significant decreases in serum PM20D1, low-density lipoprotein cholesterol (LDL-C), and albumin (ALB). Additionally, PM20D1 was negatively correlated with RA, NT-proBNP and positively correlated with PVR, ALB, 6MWD, and TAPSV. Moreover, PM20D1 has the potential as a biomarker for predicting IPAH patients’ prognosis. Finally, logistic regression analysis indicated that PM20D1, ALB, NT-proBNP, PVR, TASPV, RA and 6MWD were identified as risk factors for mortality in IPAH patients.ConclusionOur findings indicated that the serum levels of PM20D1 were significantly decreased in IPAH patients with poor prognosis. Moreover, PM20D1 was identified as a risk factor associated with mortality in IPAH patients.

Prognostic Implication of Right Ventricular Free Wall Longitudinal Strain and Right Atrial Pressure Estimated By Echocardiography in Patients With Severe Functional Tricuspid Regurgitation.

The interaction between right ventricular (RV) function and pulmonary hypertension is crucial for prognosis of patients with severe functional tricuspid regurgitation. RV free wall longitudinal strain (RVFWLS) has been reported to detect RV systolic dysfunction earlier than other conventional parameters. Although pulmonary artery systolic pressure measured by Doppler echocardiography is often underestimated in severe functional tricuspid regurgitation, right atrial pressure (RAP) estimated by echocardiography may be viewed as a prognostic factor. Impact of RAP and RVFWLS on outcome in patients with severe functional tricuspid regurgitation remains unclear. The aim of the present study was to investigate prognostic implication of RAP, RVFWLS, and their combination in this population. We retrospectively examined 377 patients with severe functional tricuspid regurgitation. RAP, pulmonary artery systolic pressure, RV fractional area change, and RVFWLS were analyzed. RAP of 15 mm Hg was classified as elevated RAP. All-cause death at 2-year follow-up was defined as the primary end point. RVFWLS provided better prognostic information than RV fractional area change by receiver operating characteristic curve analysis. In the multivariable Cox regression analysis, elevated RAP and RVFWLS of ≤18% were independent predictors of clinical outcome. Patients with RVFWLS of ≤18% had higher risk of all-cause death than those without by Kaplan-Meier curve analysis. Furthermore, when patients were stratified into 4 groups by RAP and RVFWLS, the group with elevated RAP and RVFWLS of ≤18% had the worst outcome. Elevated RAP and RVFWLS of ≤18% were independent predictors of all-cause death. The combination of elevated RAP and RVFWLS effectively stratified the all-cause death.

The plasma proteome is linked with left ventricular and left atrial function parameters in patients with chronic heart failure.

Examining the systemic biological processes in the heterogeneous syndrome of heart failure with reduced ejection fraction (HFrEF), as reflected by circulating proteins, in relation to echocardiographic characteristics, may provide insights into HF pathophysiology. We investigated the link of 4210 repeatedly measured circulating proteins with repeatedly measured echocardiographic parameters, as well as with elevated left atrial pressure (LAP), in HFrEF patients, to provide insights into underlying mechanisms. In 173 HFrEF patients, we performed six-monthly echocardiography and trimonthly blood sampling during a median follow-up of 2.7(IQR:2.5-2.8) years. We investigated circulating proteins in relation to echocardiographic parameters of left ventricular (left ventricular ejection fraction[LVEF], global longitudinal strain[GLS]), and left atrial function (left atrial reservoir strain[LASr]) and elevated LAP(E/e' ratio >15), and used gene enrichment analyses to identify underlying pathophysiological processes. We found 723, 249, 792 and 427 repeatedly measured proteins, with significant associations with LVEF, GLS, LASr and E/e' ratio, respectively. Proteins associated with LASr reflected pathophysiological mechanisms mostly related to the extracellular matrix (ECM). Proteins associated with GLS reflected cardiovascular biological processes and diseases, whereas those associated with LVEF reflected processes involved in the sympathetic nervous system. Moreover, 49 proteins were associated with elevated LAP; after correction for LVEF, three proteins remained: Cystatin-D, Fibulin-5 and HSP40. Circulating proteins show varying associations with different echocardiographic parameters in HFrEF patients. These findings suggest that pathways involved in atrial and ventricular dysfunction, as reflected by the plasma proteome, are distinct.

Congestion patterns in severe tricuspid regurgitation and transcatheter treatment: Insights from a multicentre registry.

While invasively determined congestion holds mechanistic and prognostic significance in acute heart failure (HF), its role in patients with tricuspid regurgitation (TR)-related right- heart failure (HF) undergoing transcatheter tricuspid valve intervention (TTVI) is less well established. A comprehensive understanding of congestion patterns might aid in procedural planning, risk stratification, and the identification of patients who may benefit from adjunctive therapies before undergoing TTVI. The aim of this study was to investigate the role of congestion patterns in patients with severe TR and its implications for TTVI. Within a multicentre, international TTVI registry, 813 patients underwent right heart catheterization (RHC) prior to TTVI and were followed up to 24 months. The median age was 80 (interquartile range 76-83) years and 54% were women. Both mean right atrial pressure (RAP) and pulmonary capillary wedge pressure (PCWP) were associated with 2-year mortality on Cox regression analyses with Youden index-derived cut-offs of 17 mmHg and 19 mmHg, respectively (p < 0.01 for all). However, RAP emerged as an independent predictor of outcomes following multivariable adjustments. Pre-interventionally, 42% of patients were classified as euvolaemic (RAP <17 mmHg, PCWP <19 mmHg), 23% as having left-sided congestion (RAP <17 mmHg, PCWP ≥19 mmHg), 8% as right-sided congestion (RAP ≥17 mmHg, PCWP <19 mmHg), and 27% as bilateral congestion (RAP ≥17 mmHg, PCWP ≥19 mmHg). Patients with right-sided or bilateral congestion had the lowest procedural success rates and shortest survival times. Congestion patterns allowed for discerning specific patient's physiology and specifying prognostic implications of right ventricular to pulmonary artery coupling surrogates. In this large cohort of invasively characterized patients undergoing TTVI, congestion patterns involving right-sided congestion were associated with low procedural success and higher mortality rates after TTVI. Whether pre-interventional reduction of right-sided congestion can improve outcomes after TTVI should be established in dedicated studies.

Tricuspid regurgitation in pulmonary arterial hypertension: a right ventricular volumetric and functional analysis.

The consequences of tricuspid regurgitation (TR) for right ventricular (RV) function and prognosis in pulmonary arterial hypertension (PAH) are poorly described and effects of tricuspid valve repair on the RV are difficult to predict. In 92 PAH patients with available cardiac magnetic resonance (CMR) studies, TR volume was calculated as the difference between RV stroke volume and forward stroke volume, i.e. pulmonary artery (PA) stroke volume. Survival was estimated from the time of the CMR scan to cardiopulmonary death or lung transplantation. In a subgroup, pressure-volume loop analysis including two-parallel elastances was applied to evaluate effective elastances, including net afterload (effective arterial elastance (E a)), forward afterload (effective pulmonary arterial elastance (E pa)) and backward afterload (effective tricuspid regurgitant elastance (E TR)). The effects of tricuspid valve repair were simulated using the online software package Harvi. 26% of PAH patients had a TR volume ≥30 mL. Greater TR volume was associated with increased N-terminal pro-brain natriuretic peptide (p=0.018), mean right atrial pressure (p<0.001) and RV end-systolic and -diastolic volume (both p<0.001). TR volume ≥30 mL was associated with a poor event-free survival (p=0.008). In comparison to E a, E pa correlated better with indices of RV dysfunction. Lower end-systolic elastance (E es) (p=0.002) and E TR (p=0.030), higher E pa (p=0.001) and reduced E es/E pa (p<0.001) were found in patients with a greater TR volume. Simulations predicted that tricuspid valve repair increases RV myocardial oxygen consumption in PAH patients with severe TR and low E es unless aggressive volume reduction is accomplished. In PAH, TR has prognostic significance and is associated with low RV contractility and RV-PA uncoupling. However, haemodynamic simulations showed detrimental consequences of tricuspid valve repair in PAH patients with low RV contractility.