Time from the beginning of the right ventricle isovolumetric contraction to the peak of the S wave: A new TDI indicator for the non-invasive estimation of pulmonary hypertension

Introduction: Animal models have been used to understand the pathophysiology of pulmonary hypertension, to describe the mechanisms of action and to evaluate promising active ingredients. The monocrotaline-induced pulmonary hypertension model is the most used animal model. In this model, invasive and non-invasive hemodynamic variables that resemble human measurements have been used. Aim: To define if non-invasive variables can predict hemodynamic measures in the monocrotaline-induced pulmonary hypertension model. Materials and Methods: Twenty 6-week old male Wistar rats weighing between 250-300g from the bioterium of the Universidad del Valle (Cali - Colombia) were used in order to establish that the relationships between invasive and non-invasive variables are sustained in different conditions (healthy, hypertrophy and treated). The animals were organized into three groups, a control group who was given 0.9% saline solution subcutaneously (sc), a group with pulmonary hypertension induced with a single subcutaneous dose of Monocrotaline 30 mg/kg, and a group with pulmonary hypertension with 30 mg/kg of monocrotaline treated with Sildenafil. Right ventricle ejection fraction, heart rate, right ventricle systolic pressure and the extent of hypertrophy were measured. The functional relation between any two variables was evaluated by the Pearson correlation coefficient. Results: It was found that all correlations were statistically significant (p <0.01). The strongest correlation was the inverse one between the RVEF and the Fulton index (r = -0.82). The Fulton index also had a strong correlation with the RVSP (r = 0.79). The Pearson correlation coefficient between the RVEF and the RVSP was -0.81, meaning that the higher the systolic pressure in the right ventricle, the lower the ejection fraction value. Heart rate was significantly correlated to the other three variables studied, although with relatively low correlation. Conclusion: The correlations obtained in this study indicate that the parameters evaluated in the research related to experimental pulmonary hypertension correlate adequately and that the measurements that are currently made are adequate and consistent with each other, that is, they have good predictive capacity.

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CMR markers for early right ventricular dysfunction in precapillary pulmonary hypertension

European Heart Journal ◽

10.1093/ehjci/ehaa946.0241 ◽

2020 ◽

Vol 41 (Supplement_2) ◽

Author(s):

J Vos ◽

T Leiner ◽

A.P.J Van Dijk ◽

F.J Meijboom ◽

G.T Sieswerda ◽

...

Keyword(s):

Pulmonary Hypertension ◽

Right Ventricle ◽

Right Ventricular ◽

Circumferential Strain ◽

Peak Strain ◽

Healthy Controls ◽

Free Wall ◽

Global Circumferential Strain ◽

The Right ◽

Rv Function

Abstract Introduction Precapillary pulmonary hypertension (pPH) causes right ventricular (RV) pressure overload inducing RV remodeling, often resulting in dysfunction and dilatation, heart failure, and ultimately death. The ability of the right ventricle to adequately adapt to increased pressure loading is key for patients' prognosis. RV ejection fraction (RVEF) by cardiac magnetic resonance (CMR) is related to outcome in pPH patients, but this global measurement is not ideal for detecting early changes in RV function. Strain analysis on CMR using feature tracking (FT) software provides a more detailed assessment, and might therefore detect early changes in RV function. Aim 1) To compare RV strain parameters in pPH patients and healthy controls, and 2) to compare strain parameters in a subgroup of pPH patients with preserved RVEF (pRVEF) and healthy controls. Methods In this prospective study, a CMR was performed in pPH patients and healthy controls. Using FT-software on standard cine images, the following RV strain parameters were analyzed: global, septal, and free wall longitudinal strain (GLS, sept-LS, free wall-LS), time to peak strain (TTP, as a % of the whole cardiac cycle), the fractional area change (FAC), global circumferential strain (GCS), global longitudinal and global circumferential strain rate (GLSR and GCSR, respectively). A pRVEF is defined as a RVEF >50%. To compare RV strain parameters in pPH patients to healthy controls, the Mann-Whitney U test was used. Results 33 pPH-patients (55 [45–63] yrs; 10 (30%) male) and 22 healthy controls (40 [36–48] yrs; 15 (68%) male) were included. All RV strain parameters were significantly reduced in pPH patients compared to healthy controls (see table), except for GCS and GCSR. Most importantly, in pPH patients with pRVEF (n=8) GLS (−26.6% [−22.6 to −27.3] vs. −28.1% [−26.2 to −30.6], p=0.04), sept-LS (−21.2% [−19.8 to −23.2] vs. −26.0% [−24.0 to −27.9], p=0.005), and FAC (39% [35–44] vs. 44% [42–47], p=0.02) were still significantly impaired compared to healthy controls. The RV TTP was significantly increased in pPH patients compared to healthy controls (47% [44–57] vs. 40% [33–43], p≤0.001). Conclusions Several CMR-FT strain parameters of the right ventricle are impaired in pPH patients when compared to healthy controls. Moreover, even in pPH patients with a preserved RVEF multiple RV strain parameters (GLS, sept-LS, and FAC) remained significantly impaired, and TTP significantly prolonged, in comparison to healthy controls. This suggests that RV strain parameters may be used as an early marker of RV dysfunction in pPH patients. Funding Acknowledgement Type of funding source: None

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Experimental pulmonary hypertension induced by constriction of the pulmonary arteries resulting in rupture or extraordinary dilatation of the right ventricle after administration of a little amount of Na2EDTA

Experimental and Toxicologic Pathology ◽

10.1016/s0940-2993(11)80445-8 ◽

1993 ◽

Vol 45 (1) ◽

pp. 21-27 ◽

Cited By ~ 5

Author(s):

Hisao Yamaguchi ◽

Hirokuni Kaku ◽

Masaru Morisada

Keyword(s):

Pulmonary Hypertension ◽

Right Ventricle ◽

Pulmonary Arteries ◽

The Right

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The Role of G Protein-Coupled Receptors in the Right Ventricle in Pulmonary Hypertension

Frontiers in Cardiovascular Medicine ◽

10.3389/fcvm.2018.00179 ◽

2018 ◽

Vol 5 ◽

Cited By ~ 2

Author(s):

Gayathri Viswanathan ◽

Argen Mamazhakypov ◽

Ralph T. Schermuly ◽

Sudarshan Rajagopal

Keyword(s):

Pulmonary Hypertension ◽

Right Ventricle ◽

G Protein ◽

G Protein Coupled Receptors ◽

The Right ◽

G Protein Coupled

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Right Ventricular Function in Acute Respiratory Distress Syndrome: Impact on Outcome, Respiratory Strategy and Use of Veno-Venous Extracorporeal Membrane Oxygenation

Frontiers in Physiology ◽

10.3389/fphys.2021.797252 ◽

2022 ◽

Vol 12 ◽

Author(s):

Matthieu Petit ◽

Edouard Jullien ◽

Antoine Vieillard-Baron

Keyword(s):

Pulmonary Hypertension ◽

Extracorporeal Membrane Oxygenation ◽

Right Ventricle ◽

Pulmonary Circulation ◽

Distress Syndrome ◽

Cor Pulmonale ◽

Prone Positioning ◽

Acute Cor Pulmonale ◽

Membrane Oxygenation ◽

The Right

Acute respiratory distress syndrome (ARDS) is characterized by protein-rich alveolar edema, reduced lung compliance and severe hypoxemia. Despite some evidence of improvements in mortality over recent decades, ARDS remains a major public health problem with 30% 28-day mortality in recent cohorts. Pulmonary vascular dysfunction is one of the pivot points of the pathophysiology of ARDS, resulting in a certain degree of pulmonary hypertension, higher levels of which are associated with morbidity and mortality. Pulmonary hypertension develops as a result of endothelial dysfunction, pulmonary vascular occlusion, increased vascular tone, extrinsic vessel occlusion, and vascular remodeling. This increase in right ventricular (RV) afterload causes uncoupling between the pulmonary circulation and RV function. Without any contractile reserve, the right ventricle has no adaptive reserve mechanism other than dilatation, which is responsible for left ventricular compression, leading to circulatory failure and worsening of oxygen delivery. This state, also called severe acute cor pulmonale (ACP), is responsible for excess mortality. Strategies designed to protect the pulmonary circulation and the right ventricle in ARDS should be the cornerstones of the care and support of patients with the severest disease, in order to improve prognosis, pending stronger evidence. Acute cor pulmonale is associated with higher driving pressure (≥18 cmH2O), hypercapnia (PaCO2 ≥ 48 mmHg), and hypoxemia (PaO2/FiO2 < 150 mmHg). RV protection should focus on these three preventable factors identified in the last decade. Prone positioning, the setting of positive end-expiratory pressure, and inhaled nitric oxide (INO) can also unload the right ventricle, restore better coupling between the right ventricle and the pulmonary circulation, and correct circulatory failure. When all these strategies are insufficient, extracorporeal membrane oxygenation (ECMO), which improves decarboxylation and oxygenation and enables ultra-protective ventilation by decreasing driving pressure, should be discussed in seeking better control of RV afterload. This review reports the pathophysiology of pulmonary hypertension in ARDS, describes right heart function, and proposes an RV protective approach, ranging from ventilatory settings and prone positioning to INO and selection of patients potentially eligible for veno-venous extracorporeal membrane oxygenation (VV ECMO).

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Hepatic Venous Duplex as an Alternative Non- invasive Diagnostic Tool for Diagnosis of Pulmonary Hypertension

University Heart Journal ◽

10.3329/uhj.v16i2.49665 ◽

2020 ◽

Vol 16 (2) ◽

pp. 86-91

Author(s):

Md Harisul Hoque ◽

SM Mustafa Zaman ◽

Khurshid Ahmed ◽

Sajal Krisna Banerjee ◽

Md Faisal Ibne Kabir ◽

...

Keyword(s):

Pulmonary Hypertension ◽

Diagnostic Tool ◽

Right Heart Catheterization ◽

Diagnostic Methods ◽

Heart Catheterization ◽

Right Heart ◽

Non Invasive ◽

Close Proximity ◽

The Right ◽

Practical Demonstration

Pulmonary hypertension is a hemodynamic disorder defined by abnormally high pulmonary artery pressure that affects the arteries in your lungs and the right side of your heart. In this study, hepatic venous duplex will be done to diagnose and quantify the PH. So that Patients can avoid unnecessary invasive right heart catheterization. This practical demonstration is the key to enrich our experience and knowledge in the field of PH. Objectives of this study was to assess PH status by Hepatic venous Duplex (HVD) as well by right heart catheterization and to compare them. This study was conducted in the Department of Cardiology, BSMMU, Shahbagh, Dhaka extending from July 2018 to December 2019. Total 100 (One hundred) subjects were enrolled in this study. It was an Observational study and includes the subjects between 18 years to 45 years of age. Results of this study shows very close proximity to that of Right heart catheterization. Hemodynamic changes in Hepatic venous duplex study could be used as an alternative diagnostic tool for evaluating moderate to severe pulmonary hypertension. This method could counteract the weakness of the currently used diagnostic methods and improve the accuracy of assessing pulmonary hypertension when combined with other methods. University Heart Journal Vol. 16, No. 2, Jul 2020; 86-91

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