Right Ventricular Systolic Function Research Articles

Correlation between Electrocardiogram Changes and Right Ventricular Systolic Function in Patients with Chronic Atrial Fibrillation

Background: Chronic atrial fibrillation (CAF) induces various electric disturbances, and a single mutation can cause multifarious phenotypes or combinations. Identifying the correlation of electrocardiogram changes corresponding to the disorders of electrical activity with right ventricular systolic function (RVSF) is important for the treatment and prognosis of CAF. Therefore, this study explored the correlation of electrocardiogram changes and RVSF in patients with CAF. Methods: From March 2022, to March 2023, 97 patients with CAF admitted to the Department of Cardiology of our hospital (study group) and 100 normal people who received health examination (control group) were subjected to echocardiogram and electrocardiogram to record relevant parameters for correlation analysis. Results: Significant differences were found in the electrocardiogram indices and right heart function parameters between the two groups. The study group had significantly higher heart rate, QTc interval, QT interval and T wave time than the control group (p < 0.05). The study group showed significantly higher right ventricular end-diastolic volume (RVEDV) and right ventricular end-systolic volume (RVESV), and lower right ventricular stroke volume (RVSV) and right ventricular ejection fraction (RVEF) than the control group (p < 0.05). Pearson correlation analysis showed that QTc interval, QT interval, and T wave time were positively correlated with RVESV (p < 0.05); QTc interval, QT interval, and T wave time were negatively correlated with RVSV (p < 0.05); and QTc interval was negatively correlated with RVEF (p < 0.05). Conclusion: A correlation exists between electrocardiogram changes and RVSF in patients with CAF.

Prognostic value of the echocardiographic ratio tricuspid annular plane systolic excursion / pulmonary arterial systolic pressure in acute pulmonary embolism.

The occurrence of death from acute pulmonary embolism (PE) is often linked to right ventricular (RV) failure, arising from an imbalance between RV systolic function and heightened RV afterload. In our study, we posited that an echocardiographic ratio derived from this disparity [RV systolic function assessed by tricuspid annular plane systolic excursion (TAPSE) divided by pulmonary arterial systolic pressure (PASP)] could offer superior predictive value for adverse outcomes compared to individual measurements of TAPSE and PASP alone. We conducted a retrospective analysis using data from a University Hospital Centre spanning from 2017 to 2023. All individuals with confirmed PE and a formal transthoracic echocardiogram within 7 days of diagnosis were included. The primary endpoint was a composite outcome of death, hemodynamic deterioration needing introduction of inotropes or thrombolysis within 30 days. Secondary endpoints included 6 months all-cause mortality and onset of right-sided heart failure. Thirty-eight patients were included. Mean age was 58 ±15 years old. A male predominance was noted: 23 male patients (60.5%) and 15 female patients (39.5%). Eight patients met the primary composite endpoint while nine patients met the secondary composite endpoint. In multivariate analysis, the TAPSE/PASP ratio was independently associated with the primary outcome (OR=2.77, 95% CI 1.101-10.23, P=0.042). A TAPSE/PASP ratio <0.3 was independently associated with the secondary outcome (OR=3.07, 95% CI 1.185-10.18, P=0.034). This study suggests that a combined echocardiographic ratio of RV function to afterload is effective in predicting adverse outcomes in acute PE.

Low circulating lysophosphatidylcholine and phosphatidylcholine are linked to pulmonary hypertension severity

Background: Pulmonary hypertension (PH) is a progressive pulmonary vascular disease. Given the mechanistic role of lipids in peripheral vascular diseases, we hypothesized that PH is also associated with pathologic circulating lipid metabolites. To test this, lipid metabolites of patients with PH were evaluated in association with clinical severity, including right ventricle systolic pressure (RVSP), pulmonary vascular resistance (PVR), right ventricular size and function, and plasma endothelin-1. Methods and Results: Participants were recruited as a part of a small site clinical trial (Clinicaltrials.gov, # NCT01586156). Comprehensive lipidomes were determined using unbiased nontargeted lipidomics (Metabolon Inc., Durham, NC) in 30 PH patients and 12 healthy controls. RVSP, right ventricular end diastolic (RVED) and end systolic (RVES) area were measured by echocardiogram and PVR was calculated. Plasma endothelin-1 was measured by Elisa. Nontargeted analysis detected 1099 lipid-related metabolites of which 83 and 60 metabolites were upregulated and downregulated in PH ( p&lt;0.05), respectively. Pathway enrichment analysis identified abnormalities of lipid metabolic pathways including choline-related, acylcarnitine, and sphingolipid metabolism. Targeted measures of lysophosphatidylcholine (lysoPC) and phosphatidylcholine (PC) confirmed these findings. Total circulating lysoPC and PC were downregulated [Healthy vs. PH, mean ± SD, mM; LysoPC, 786±102 vs. 586±139, p&lt;0.01; PC, 1855±389 vs. 1495±282, p&lt;0.01]. Sixteen out of the 25 lysoPC detected, and 25 out of 39 PC detected, were lower in PH, including the most abundant lysoPC-16:0 [226±31 vs. 186±39, p&lt;0.01] and PC-34:2 [436±91 vs. 360±75, p&lt;0.01]. RVSP, PVR, RVED area, RVES area and endothelin-1 were all higher in PH (all, p&lt;0.01). Lipid metabolites were inversely related to clinical measures of PH severity. For example, lysoPC-20:3 was related to RVSP [ r=−0.63, p&lt;0.01], PVR [ r=−0.50, p&lt;0.01], and endothelin-1 [ r=−0.51, p&lt;0.01], and PC-36:5 was inversely related to RVSP [ r=−0.36, p=0.02], PVR [ r=−0.43, p&lt;0.01], and endothelin-1 [ r=−0.50, p&lt;0.01]. Additionally, both lysoPC-20:3 and PC36:5 metabolites were inversely associated with right ventricular size, measured as RVED area [lysoPC-20:3, r=−0.62, p&lt;0.01; PC-36:5, r=−0.69, p&lt;0.01], RVES area [lysoPC-20:3, r=−0.66, p&lt;0.01; PC-36:5, r=−0.71, p&lt;0.01] and related with RV systolic function, measured as RV fractional area change [lysoPC-20:3, r=0.57, p&lt;0.01; PC-36:5, r=0.50, p&lt;0.01). Conclusion: Plasma phosphatidylcholine is low in PH and is associated with disease severity, suggesting disturbances in PC metabolism are important in pulmonary vascular disease. NIH NHLBI R37HL60917, R01HL115008 CTSA UL1TR000439; UL1TR002548. 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.

Impact of modulating pulmonary artery pressure on resting right ventricular function in endurance-trained and untrained individuals

Prolonged endurance training is associated with critical adaptations to right ventricular (RV) structure and function that facilitate the achievement of higher exercise capacity, peak cardiac output, and RV stroke volume in the face of large increases in pulmonary artery pressures (afterload) and RV wall stress. Compared to the left ventricle, the RV is more sensitive to increases in afterload during exercise. However, the independent effect of increased afterload on RV function in endurance trained (Trained) vs untrained individuals remain unknown. Trained were considered those with a maximal oxygen consumption ( V̇O2max) &gt;60ml/kg/min (male) or &gt;55ml/kg/min (female) while untrained were defined as V̇O2max &lt;45ml/kg/min. Using echocardiography, this retrospective study sought to evaluate RV systolic function (RV global longitudinal strain [GLS]) and ventriculo-arterial coupling (ratio of RV GLS to pulmonary artery systolic pressure [PASP]) in Trained and untrained individuals while manipulating PASP. Ten participants (5 Trained and 5 Untrained) underwent resting echocardiography while breathing moderate (pressure of inspired oxygen; PiO2=89 mmHg) and severe hypoxia (PiO2=79 mmHg; order randomized) to increase PASP. Separately, eight participants (4 Trained and 4 untrained) inhaled nitric oxide (iNO; 40ppm) during echocardiography to lower PASP. Moderate and severe hypoxia increased PASP by 2.3 ± 1.3mmHg and 3.5 ± 1.8mmHg, respectively, while iNO decreased PASP by 2.6 ± 2.4mmHg, with no between group differences observed. Cardiac output was not different between any condition. A fitness-by-hypoxia interaction was observed in RV GLS in moderate hypoxia suggesting Trained had lower RV function during moderate hypoxia as compared to untrained (Untrained: -23.1 ± 4.4% vs. Trained: -20.2 ± 2.7%; p&lt;0.01). No differences in RV GLS were observed with iNO (p=0.98). The ratio of RV GLS to PASP was significantly different between groups at moderate hypoxia (Untrained: -1.06 ± 0.09%/mmHg vs. Trained: -0.85 ± 0.12%/mmHg; p=0.04) but not severe hypoxia (p=0.78). These findings suggest reducing PASP did not alter RV function or ventriculo-arterial coupling, however, Trained individuals experienced differential RV function responses when PASP is experimentally increased with hypoxia. Natural Sciences and Engineering Research Council of Canada. 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.

Incomplete reverse remodeling in aged mice exposed to pulmonary hypertension-induced right ventricular failure

Right ventricle (RV) function is the strongest predictor of survival in pulmonary hypertension (PH) and age-related HF; however no therapies exist to improve RV function. Understanding mechanisms by which the RV undoes pathological remodeling (reverse remodeling) might aid in identifying therapies for this unmet need. Our objective was to determine whether the aged RV can undergo reverse remodeling following pathological afterload (PH). We hypothesized that return to normoxia after hypoxia-induced PH would result in attenuation of RV mass and improved RV function. We exposed male and female aged (~18 months) C57Bl6 mice to hypobaric hypoxia (HH) for 4 weeks before returning them to normoxia for 3 (WK3RR) or 6 (WK6RR) weeks. HH induced RV hypertrophy by RV myocyte area which was attenuated at Wk3RR and WK6RR in both male (Con: 425 μm2 ± 104, HH: 740 μm2 ± 125, WK3RR: 447 μm2 ± 129, WK6RR: 530 μm2 ± 187) and female mice (Con: 340 μm2 ± 116, HH: 770 μm2 ± 35, WK3RR: 516 μm2 ± 186, WK6RR: 655 μm2 ± 224). HH stimulated fibrosis by collagen deposition that was also reversed during normoxia re-exposure in male mice only (Con: 4.1% ± 1.0, HH: 10.8% ± 0.8, WK3RR: 4.2% ± 0.8, WK6RR: 2.5% ± 0.7). However, HH decreased RV systolic function by fractional area change (FAC) that was also not rescued by normoxia re-exposure. The aged RV can undergo morphological reverse remodeling in response to HH; however RV function does not improve with resolution of afterload. Further investigation into the mechanisms of reverse remodeling may identify potential drug therapies for maladaptive RV remodeling. AHA-Predoctoral Fellowship 897622 (BDM). 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.

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.

Significant Disagreement Between Conventional Parameters and 3D Echocardiography-Derived Ejection Fraction in the Detection of Right Ventricular Systolic Dysfunction and Its Association With Outcomes

Conventional echocardiographic parameters such as tricuspid annular plane systolic excursion (TAPSE), fractional area change (FAC), and free-wall longitudinal strain (FWLS) offer limited insights into the complexity of right ventricular (RV) systolic function, while 3D echocardiography-derived RV ejection fraction (RVEF) enables a comprehensive assessment. We investigated the discordance between TAPSE, FAC, FWLS, and RVEF in RV systolic function grading and associated outcomes. We analyzed two- and three-dimensional echocardiography data from 2 centers including 750 patients followed up for all-cause mortality. Right ventricular dysfunction was defined as RVEF <45%, with guideline-recommended thresholds (TAPSE <17mm, FAC <35%, FWLS >-20%) considered. Among patients with normal RVEF, significant proportions exhibited impaired TAPSE (21%), FAC (33%), or FWLS (8%). Conversely, numerous patients with reduced RVEF had normal TAPSE (46%), FAC (26%), or FWLS (41%). Using receiver-operating characteristic analysis, FWLS exhibited the highest area under the curve of discrimination for RV dysfunction (RVEF <45%) with 59% sensitivity and 92% specificity. Over a median 3.7-year follow-up, 15% of patients died. Univariable Cox regression identified TAPSE, FAC, FWLS, and RVEF as significant mortality predictors. Combining impaired conventional parameters showed that outcomes are the worst if at least 2 parameters are impaired and gradually better if only one or none of them are impaired (log-rank P<.005). Guideline-recommended cutoff values of conventional echocardiographic parameters of RV systolic function are only modestly associated with RVEF-based assessment. Impaired values of FWLS showed the closest association with the RVEF cutoff. Our results emphasize a multiparametric approach in the assessment of RV function, especially if 3D echocardiography is not available.

The Effects of Radiofrequency Catheter Ablation for Atrial Fibrillation on Right Ventricular Function.

The effects of radiofrequency catheter ablation (RFCA) for atrial fibrillation (AF) on right ventricular (RV) function are not well known. Patients who underwent RFCA for AF and underwent pre- and post-procedural echocardiography were enrolled consecutively. Fractional area change (FAC), RV free-wall longitudinal strain (RVFWSL), and RV 4-chamber strain including the ventricular septum (RV4CSL) were measured. Changes in FAC, RVFWSL, and RV4CSL before and after RFCA were compared among paroxysmal AF (PAF), persistent AF (PeAF), and long-standing persistent AF (LSPeAF) groups. A total of 164 participants (74 PAF, 47 PeAF, and 43 LSPeAF; age, 60.8 ± 9.8 years; men, 74.4%) was enrolled. The patients with PeAF and LSPeAF had worse RV4CSL (p<0.001) and RVFWSL (p<0.001) than those with PAF and reference values. Improvements in RVFWSL and RV4CSL after RFCA were significant in the PeAF group compared with the PAF and LSPeAF groups (ΔRV4CSL, 8.4% [5.1, 11.6] in PeAF vs. 1.0% [-1.0, 4.1] in PAF, 1.9% [-0.2, 4.4] in LSPeAF, p<0.001; ΔRVFWSL, 9.0% [6.9, 11.5] in PeAF vs. 0.9% [-1.4, 4.9] in PAF, 1.0% [-1.0, 3.6] in LSPeAF, p<0.001). In patients without recurrence, improvements in RVFWSL and RV4CSL after RFCA were significant in the PeAF group compared to the LSPeAF group. RV systolic function is more impaired in patients with PeAF and LSPeAF than in those with PAF. RV systolic function is more improved after RFCA in patients with PeAF than in those with PAF or LSPeAF.

Exploratory analysis of the accuracy of echocardiographic parameters for the assessment of right ventricular function and right ventricular–pulmonary artery coupling

AbstractEchocardiography is a widely used modality for the assessment of right ventricular (RV) function; however, few studies have comprehensively compared the accuracy of echocardiographic parameters using invasively obtained reference values. Therefore, this exploratory study aimed to compare the accuracy of echocardiographic parameters of RV function and RV–pulmonary artery (PA) coupling. We calculated four indices of RV function (end‐systolic elastance [Ees] for systolic function [contractility], τ for relaxation, and β and end‐diastolic elastance [Eed] for stiffness), and an index of RV–PA coupling (Ees/arterial elastance [Ea]), using pressure catheterization, cardiac magnetic resonance imaging, and a single‐beat method. We then compared the correlations of RV indices with echocardiographic parameters. In 63 participants (54 with pulmonary hypertension (PH) and nine without PH), Ees and τ correlated with several echocardiographic parameters, such as RV diameter and area, but the correlations were moderate (|correlation coefficients (ρ)| &lt; 0.5 for all parameters). The correlations of β and Eed with echocardiographic parameters were weak, with |ρ| &lt; 0.4. In contrast, Ees/Ea closely correlated with RV free wall longitudinal strain (RVFW‐LS)/estimated systolic PA pressure (eSPAP) (ρ = −0.72). Ees/Ea also correlated with tricuspid annular plane systolic excursion/eSPAP, RV diameter, and RV end‐systolic area, with |ρ | &gt;0.65. In addition, RVFW‐LS/eSPAP yielded high sensitivity (0.84) and specificity (0.75) for detecting reduced Ees/Ea. The present study indicated a limited accuracy of echocardiographic parameters in assessing RV systolic and diastolic function. In contrast to RV function, they showed high accuracy for assessing RV–PA coupling, with RVFW‐LS/eSPAP exhibiting the highest accuracy.

Association between right ventricular global longitudinal strain and mortality in intermediate-risk pulmonary embolism.

Right ventricular (RV) systolic dysfunction has been identified as a prognostic marker for adverse clinical events in patients presenting with acute pulmonary embolism (PE). However, challenges exist in identifying RV dysfunction using conventional echocardiography techniques. Strain echocardiography is an evolving imaging modality which measures myocardial deformation and can be used as an objective index of RV systolic function. This study evaluated RV Global Longitudinal Strain (RVGLS) in patients with intermediate risk PE as a parameter of RV dysfunction, and compared to traditional echocardiographic and CT parameters evaluating short-term mortality. Retrospective single center cohort study of 251 patients with intermediate-risk PE between 2010 and 2018. The primary outcome was all-cause mortality at 30 days. Statistical analysis evaluated each parameter comparing survivors versus non-survivors at 30 days. Receiver operating characteristic (ROC) curves and Kaplan-Meier curves were used for comparison of the two cohorts. Altogether 251 patients were evaluated. Overall mortality rate was 12.4%. Utilizing an ROC curve, an absolute cutoff value of 17.7 for RVGLS demonstrated a sensitivity of 93% and specificity of 70% for observed 30-day mortality. Individuals with an RVGLS ≤17.7 had a 25 times higher mortality rate than those with RVGLS above 17.7 (HR 25.24, 95% CI=6.0-106.4, p<.001). Area under the curve was (.855), RVGLS outperformed traditional echocardiographic parameters, CT findings, and cardiac biomarkers on univariable and multivariable analysis. Reduced RVGLS values on initial echocardiographic assessment of patients with intermediate-risk PE identified patients at higher risk for mortality at 30 days.

Deep learning to assess right ventricular ejection fraction from two-dimensional echocardiograms in precapillary pulmonary hypertension.

Precapillary pulmonary hypertension (PH) is characterized by a sustained increase in right ventricular (RV) afterload, impairing systolic function. Two-dimensional (2D) echocardiography is the most performed cardiac imaging tool to assess RV systolic function; however, an accurate evaluation requires expertise. We aimed to develop a fully automated deep learning (DL)-based tool to estimate the RV ejection fraction (RVEF) from 2D echocardiographic videos of apical four-chamber views in patients with precapillary PH. We identified 85 patients with suspected precapillary PH who underwent cardiac magnetic resonance imaging (MRI) and echocardiography. The data was divided into training (80%) and testing (20%) datasets, and a regression model was constructed using 3D-ResNet50. Accuracy was assessed using five-fold cross validation. The DL model predicted the cardiac MRI-derived RVEF with a mean absolute error of 7.67%. The DL model identified severe RV systolic dysfunction (defined as cardiac MRI-derived RVEF<37%) with an area under the curve (AUC) of.84, which was comparable to the AUC of RV fractional area change (FAC) and tricuspid annular plane systolic excursion (TAPSE) measured by experienced sonographers (.87 and.72, respectively). To detect mild RV systolic dysfunction (defined as RVEF ≤ 45%), the AUC from the DL-predicted RVEF also demonstrated a high discriminatory power of.87, comparable to that of FAC (.90), and significantly higher than that of TAPSE (.67). The fully automated DL-based tool using 2D echocardiography could accurately estimate RVEF and exhibited a diagnostic performance for RV systolic dysfunction comparable to that of human readers.

Septic cardiomyopathy phenotype in the critically ill may depend on antimicrobial resistance

BackgroundSepsis is a life-threatening organ dysfunction, and septic cardiomyopathy (SCM) may complicate the course of the disease. Infection with multidrug-resistant (MDR) pathogens has been linked with worse outcomes. This study aims to evaluate SCM in patients with infections caused by different antimicrobial-resistant phenotypes. MethodThis retrospective study included patients with sepsis/septic shock, hospitalized, and intubated in the intensive care unit of the University Hospital of Larissa between January 2022 and September 2023 with echocardiographic data during the first two days after infection onset. The patients were divided into two groups: a non-MDR-SCM and an MDR-SCM. The cardiac function was compared between the two groups. ResultA total of 62 patients were included in the study. Twenty-six patients (41.9%) presented with left ventricular (LV) systolic dysfunction, and ≤35% right ventricular fractional area change (RVFAC) was present in 56.4%. Forty-four patients comprised the MDR-SCM and 18 the non-MDR-SCM group. LV systolic function was more severely impaired in the non-MDR-SCM group (left ventricular ejection fraction, 35.8±4.9% vs. 45.6±2.4%, P=0.049; LV outflow tract velocity time integral, 10.1±1.4 cm vs. 15.3±0.74 cm, P=0.001; LV-Strain, -9.02±0.9% vs. -14.02±0.7%, P=0.001). The MDR-SCM group presented with more severe right ventricular (RV) dilatation (right ventricular end-diastolic area/left ventricular end-diastolic area, 0.81±0.03 vs. 0.7±0.05, P=0.042) and worse RV systolic function (RVFAC, 32.3±1.9% vs. 39.6±2.7%, P=0.035; tricuspid annular plane systolic excursion, 15.9±0.9 mm vs. 18.1±0.9 mm, P=0.165; systolic tissue Doppler velocity measured at the lateral tricuspid annulus, 9.9±0.5 cm/s vs. 13.1±0.8 cm/s, P=0.002; RV-strain, -11.1±0.7% vs. -15.1±0.9%, P=0.002). ConclusionSCM related to MDR infection presents with RV systolic dysfunction predominance, while non-MDR-SCM is mainly depicted with LV systolic dysfunction impairment.

Metabolic changes contribute to maladaptive right ventricular hypertrophy in pulmonary hypertension beyond pressure overload: an integrative imaging and omics investigation.

Right ventricular (RV) failure remains the strongest determinant of survival in pulmonary hypertension (PH). We aimed to identify relevant mechanisms, beyond pressure overload, associated with maladaptive RV hypertrophy in PH. To separate the effect of pressure overload from other potential mechanisms, we developed in pigs two experimental models of PH (M1, by pulmonary vein banding and M2, by aorto-pulmonary shunting) and compared them with a model of pure pressure overload (M3, pulmonary artery banding) and a sham-operated group. Animals were assessed at 1 and 8 months by right heart catheterization, cardiac magnetic resonance and blood sampling, and myocardial tissue was analyzed. Plasma unbiased proteomic and metabolomic data were compared among groups and integrated by an interaction network analysis. A total of 33 pigs completed follow-up (M1, n = 8; M2, n = 6; M3, n = 10; and M0, n = 9). M1 and M2 animals developed PH and reduced RV systolic function, whereas animals in M3 showed increased RV systolic pressure but maintained normal function. Significant plasma arginine and histidine deficiency and complement system activation were observed in both PH models (M1&M2), with additional alterations to taurine and purine pathways in M2. Changes in lipid metabolism were very remarkable, particularly the elevation of free fatty acids in M2. In the integrative analysis, arginine-histidine-purines deficiency, complement activation, and fatty acid accumulation were significantly associated with maladaptive RV hypertrophy. Our study integrating imaging and omics in large-animal experimental models demonstrates that, beyond pressure overload, metabolic alterations play a relevant role in RV dysfunction in PH.

The selective serotonin reuptake inhibitor paroxetine improves right ventricular systolic function in experimental pulmonary hypertension

BackgroundPulmonary hypertension (PH) often leads to right ventricle (RV) failure, a significant cause of morbidity and mortality. Despite advancements in PH management, progression to RV maladaptation and subsequent failure remain a clinical challenge. This study explored the effect of paroxetine, a selective serotonin reuptake inhibitor (SSRI), on RV function in a rat model of PH, hypothesizing that it improves RV function by inhibiting G protein-coupled receptor kinase 2 (GRK2) and altering myofilament protein phosphorylation. MethodsThe Su5416/hypoxia (SuHx) rat model was used to induce PH. Rats were treated with paroxetine and compared to vehicle-treated and control groups. Parameters measured included RV morphology, systolic and diastolic function, myofilament protein phosphorylation, GRK2 activity, and sympathetic nervous system (SNS) markers. ResultsParoxetine treatment significantly improved RV systolic function, evidenced by increased stroke volume, cardiac output, and ejection fraction, without significantly affecting RV hypertrophy, myosin heavy chain/titin isoform switching, or fibrosis. Enhanced phosphorylation of titin and myosin light chain-2 was observed, correlating positively with improved systolic function. Contrary to the hypothesis, improvements occurred independently of GRK2 inhibition or SNS modulation, suggesting an alternate mechanism, potentially involving antioxidant properties of paroxetine. ConclusionParoxetine improves RV systolic function in PH rats, likely through mechanisms beyond GRK2 inhibition, possibly related to its antioxidant effects. This highlights the potential of paroxetine in managing RV dysfunction in PH, warranting further investigation into its detailed mechanisms of action and clinical applicability.

Feasibility Value of Right Ventricular Longitudinal Shortening Fraction and the Prognostic Implications in Patients With Heart Transplantation.

Right ventricular longitudinal shortening fraction (RVLSF) is a 2-dimensional speckle tracking echocardiography parameter based on tricuspid annular displacement analysis that could be used to assess right ventricular (RV) systolic function. The value of RVLSF in the assessment of RV systolic function in recipients of heart transplantation (HT) and whether RVLSF can replace strain parameters remains unknown. A total of 153 adult patients who underwent HT were consecutively enrolled in this prospective longitudinal study. All subjects were examined by conventional transthoracic 2-dimensional echocardiography and 2-dimensional speckle tracking echocardiography to evaluate the RV end-diastolic basal diameter, RV end-diastolic area, fractional area change, peak systolic velocity of tricuspid annulus, tricuspid annular plane systolic excursion, RV free wall strain, and RVLSF. Cox proportional hazards regression was used to test if the parameters of interest had independent prognostic value for adverse outcome prediction in patients who underwent HT. A significant positive correlation was found between the measurements of RVLSF and RV free wall strain (r=0.927, P<0.001). Compared with the event-free group, the adverse outcome group displayed reduced RVLSF and RV free wall strain and higher age (P<0.001, <0.001, =0.016, respectively) in patients who underwent HT. RVLSF and RV free wall strain were independently associated with poor prognosis in multivariable analysis (both P<0.001). RVLSF assessment provides an effective evaluation of RV longitudinal systolic function in the transplanted hearts and has prognostic value for adverse outcomes in patients undergoing HT.

The Effect of Recruitment Maneuvers on Cerebrovascular Dynamics and Right Ventricular Function in Patients with Acute Brain Injury: A Single-Center Prospective Study.

Optimization of ventilatory settings is challenging for patients in the neurointensive care unit, requiring a balance between precise gas exchange control, lung protection, and managing hemodynamic effects of positive pressure ventilation. Although recruitment maneuvers (RMs) may enhance oxygenation, they could also exert profound undesirable systemic impacts. The single-center, prospective study investigated the effects of RMs (up-titration of positive end-expiratory pressure) on multimodal neuromonitoring in patients with acute brain injury. Our primary focus was on intracranial pressure and secondarily on cerebral perfusion pressure (CPP) and other neurological parameters: cerebral autoregulation [pressure reactivity index (PRx)] and regional cerebral oxygenation (rSO2). We also assessed blood pressure and right ventricular (RV) function evaluated using tricuspid annular plane systolic excursion. Results are expressed as the difference (Δ) from baseline values obtained after completing the RMs. Thirty-two patients were enrolled in the study. RMs resulted in increased intracranial pressure (Δ = 4.8mm Hg) and reduced CPP (ΔCPP = -12.8mm Hg) and mean arterial pressure (difference in mean arterial pressure = -5.2mm Hg) (all p < 0.001). Cerebral autoregulation worsened (ΔPRx = 0.31 a.u.; p < 0.001). Despite higher systemic oxygenation (difference in partial pressure of O2 = 4mm Hg; p = 0.001) and unchanged carbon dioxide levels, rSO2 marginally decreased (ΔrSO2 = -0.5%; p = 0.031), with a significant drop in arterial content and increase in the venous content. RV systolic function decreased (difference in tricuspid annular plane systolic excursion = -0.1cm; p < 0.001) with a tendency toward increased RV basal diameter (p = 0.06). Grouping patients according to ΔCPP or ΔPRx revealed that those with poorer tolerance to RMs had higher CPP (p = 0.040) and a larger RV basal diameter (p = 0.034) at baseline. In patients with acute brain injury, RMs appear to have adverse effects on cerebral hemodynamics. These findings might be partially explained by RM's impact on RV function. Further advanced echocardiography monitoring is required to prove this hypothesis.

Comprehensive temporal analysis of right ventricular function and pulmonary haemodynamics in mechanically ventilated COVID-19 ARDS patients

BackgroundCardiac injury is frequently reported in COVID-19 patients, the right ventricle (RV) is mostly affected. We systematically evaluated the cardiac function and longitudinal changes in severe COVID-19 acute respiratory distress syndrome (ARDS) admitted to the intensive care unit (ICU) and assessed the impact on survival.MethodsWe prospectively performed comprehensive echocardiographic analysis on mechanically ventilated COVID-19 ARDS patients, using 2D/3D echocardiography. We defined left ventricular (LV) systolic dysfunction as ejection fraction (EF) < 40%, or longitudinal strain (LS) > − 18% and right ventricular (RV) dysfunction if two indices among fractional area change (FAC) < 35%, tricuspid annulus systolic plane excursion (TAPSE) < 1.6 cm, RV EF < 44%, RV–LS > − 20% were present. RV afterload was assessed from pulmonary artery systolic pressure (PASP), PASP/Velocity Time Integral in the right ventricular outflow tract (VTIRVOT) and pulmonary acceleration time (PAcT). TAPSE/PASP assessed the right ventriculoarterial coupling (VACR).ResultsAmong 176 patients included, RV dysfunction was common (69%) (RV–EF 41.1 ± 1.3%; RV–FAC 36.6 ± 0.9%, TAPSE 20.4 ± 0.4mm, RV–LS:− 14.4 ± 0.4%), usually accompanied by RV dilatation (RVEDA/LVEDA 0.82 ± 0.02). RV afterload was increased in most of the patients (PASP 33 ± 1.1 mmHg, PAcT 65.3 ± 1.5 ms, PASP/VTIRVOT, 2.29 ± 0.1 mmHg/cm). VACR was 0.8 ± 0.06 mm/mmHg. LV–EF < 40% was present in 21/176 (11.9%); mean LV–EF 57.8 ± 1.1%. LV–LS (− 13.3 ± 0.3%) revealed a silent LV impairment in 87.5%. A mild pericardial effusion was present in 70(38%) patients, more frequently in non-survivors (p < 0.05). Survivors presented significant improvements in respiratory physiology during the 10th ICU-day (PaO2/FiO2, 231.2 ± 11.9 vs 120.2 ± 6.7 mmHg; PaCO2, 43.1 ± 1.2 vs 53.9 ± 1.5 mmHg; respiratory system compliance—CRS, 42.6 ± 2.2 vs 27.8 ± 0.9 ml/cmH2O, all p < 0.0001). Moreover, survivors presented significant decreases in RV afterload (PASP: 36.1 ± 2.4 to 20.1 ± 3 mmHg, p < 0.0001, PASP/VTIRVOT: 2.5 ± 1.4 to 1.1 ± 0.7, p < 0.0001 PAcT: 61 ± 2.5 to 84.7 ± 2.4 ms, p < 0.0001), associated with RV systolic function improvement (RVEF: 36.5 ± 2.9% to 46.6 ± 2.1%, p = 0.001 and RV–LS: − 13.6 ± 0.7% to − 16.7 ± 0.8%, p = 0.001). In addition, RV dilation subsided in survivors (RVEDA/LVEDA: 0.8 ± 0.05 to 0.6 ± 0.03, p = 0.001). Day-10 CRS correlated with RV afterload (PASP/VTIRVOT, r: 0.535, p < 0.0001) and systolic function (RV–LS, 0.345, p = 0.001). LV–LS during the 10th ICU-day, while ΔRV–LS and ΔPASP/RVOTVTI were associated with survival.ConclusionsCOVID-19 improvements in RV function, RV afterload and RV–PA coupling at day 10 were associated with respiratory function and survival.

Meta-Analysis of Normal Reference Values for Right and Left Ventricular Quantification by Cardiovascular Magnetic Resonance.

Cardiovascular magnetic resonance (CMR) reference values are relied upon to accurately diagnose left ventricular (LV) and right ventricular (RV) pathologies. To date, reference values have been derived from modest sample sizes with limited patient diversity and attention to 1 but not both commonly used tracing techniques for papillary muscles and trabeculations. We sought to overcome these limitations by meta-analyzing normal reference values for CMR parameters stemming from multiple countries, vendors, analysts, and patient populations. We comprehensively extracted published and unpublished data from studies reporting CMR parameters in healthy adults. A steady-state free-precession short-axis stack at 1.5T or 3T was used to trace either counting the papillary muscles and trabeculations in the LV volume or mass. We used a novel Bayesian hierarchical meta-analysis model to derive the pooled lower and upper reference values for each CMR parameter. Our model accounted for the expected differences between tracing techniques by including informative prior distributions from a large external data set. A total of 254 studies from 25 different countries were systematically reviewed, representing 12 812 healthy adults, of which 52 were meta-analyzed. For LV parameters counting papillary muscles and trabeculations in the LV volume, pooled normative reference ranges in men and women, respectively, were as follows: LV ejection fraction of 52% to 73% and 54% to 75%, LV end-diastolic volume index of 60 to 109 and 56 to 96 mL/m2, LV end-systolic volume index of 18 to 45 and 16 to 38 mL/m2, and LV mass index of 41 to 76 and 33 to 57 g/m2. For LV parameters counting papillary muscles and trabeculations in the LV mass, pooled normative reference ranges in men and women, respectively, were as follows: LV ejection fraction of 57% to 74% and 57% to 75%, LV end-diastolic volume index of 60 to 97 and 55 to 88 mL/m2, LV end-systolic volume index of 18 to 37 and 15 to 34 mL/m2, and LV mass index of 50 to 83 and 38 to 65 g/m2. For RV parameters, pooled normative reference ranges in men and women, respectively, were as follows: RV ejection fraction of 47% to 68% and 49% to 71%, RV end-diastolic volume index of 64 to 115 and 57 to 99 mL/m2, RV end-systolic volume index of 23 to 52 and 18 to 42 mL/m2, and RV mass index of 14 to 29 and 13 to 25 g/m2. Our Bayesian hierarchical meta-analysis provides normative reference values for CMR parameters of LV and RV size, systolic function, and mass, encompassing both tracing techniques across a diverse multinational sample of healthy men and women.

Identifying the Causes of Unexplained Dyspnea at High Altitude Using Normobaric Hypoxia with Echocardiography.

Exposure to high altitude results in hypobaric hypoxia, leading to physiological changes in the cardiovascular system that may result in limiting symptoms, including dyspnea, fatigue, and exercise intolerance. However, it is still unclear why some patients are more susceptible to high-altitude symptoms than others. Hypoxic simulation testing (HST) simulates changes in physiology that occur at a specific altitude by asking the patients to breathe a mixture of gases with decreased oxygen content. This study aimed to determine whether the use of transthoracic echocardiography (TTE) during HST can detect the rise in right-sided pressures and the impact of hypoxia on right ventricle (RV) hemodynamics and right to left shunts, thus revealing the underlying causes of high-altitude signs and symptoms. A retrospective study was performed including consecutive patients with unexplained dyspnea at high altitude. HSTs were performed by administrating reduced FiO2 to simulate altitude levels specific to patients' history. Echocardiography images were obtained at baseline and during hypoxia. The study included 27 patients, with a mean age of 65 years, 14 patients (51.9%) were female. RV systolic pressure increased at peak hypoxia, while RV systolic function declined as shown by a significant decrease in the tricuspid annular plane systolic excursion (TAPSE), the maximum velocity achieved by the lateral tricuspid annulus during systole (S' wave), and the RV free wall longitudinal strain. Additionally, right-to-left shunt was present in 19 (70.4%) patients as identified by bubble contrast injections. Among these, the severity of the shunt increased at peak hypoxia in eight cases (42.1%), and the shunt was only evident during hypoxia in seven patients (36.8%). In conclusion, the use of TTE during HST provides valuable information by revealing the presence of symptomatic, sustained shunts and confirming the decline in RV hemodynamics, thus potentially explaining dyspnea at high altitude. Further studies are needed to establish the optimal clinical role of this physiologic method.

How to assess and treat right ventricular electromechanical dyssynchrony in post-repair tetralogy of Fallot: insights from imaging, invasive studies, and computational modelling.

Right bundle branch block (RBBB) and resulting right ventricular (RV) electromechanical discoordination are thought to play a role in the disease process of subpulmonary RV dysfunction that frequently occur post-repair tetralogy of Fallot (ToF). We sought to describe this disease entity, the role of pulmonary re-valvulation, and the potential added value of RV cardiac resynchronization therapy (RV-CRT). Two patients with repaired ToF, complete RBBB, pulmonary regurgitation, and significantly decreased RV function underwent echocardiography, cardiac magnetic resonance, and an invasive study to evaluate the potential for RV-CRT as part of the management strategy. The data were used to personalize the CircAdapt model of the human heart and circulation. Resulting Digital Twins were analysed to quantify the relative effects of RV pressure and volume overload and to predict the effect of RV-CRT. Echocardiography showed components of a classic RV dyssynchrony pattern which could be reversed by RV-CRT during invasive study and resulted in acute improvement in RV systolic function. The Digital Twins confirmed a contribution of electromechanical RV dyssynchrony to RV dysfunction and suggested improvement of RV contraction efficiency after RV-CRT. The one patient who underwent successful permanent RV-CRT as part of the pulmonary re-valvulation procedure carried improvements that were in line with the predictions based on his Digital Twin. An integrative diagnostic approach to RV dysfunction, including the construction of Digital Twins may help to identify candidates for RV-CRT as part of the lifetime management of ToF and similar congenital heart lesions.