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Cardiovascular Engineering and... Jun 2020Additional pulmonary blood flow (APBF) can provide better pulsating blood flow and systemic arterial oxygen saturation, while low blood pulsation and low oxygen...
PURPOSE
Additional pulmonary blood flow (APBF) can provide better pulsating blood flow and systemic arterial oxygen saturation, while low blood pulsation and low oxygen saturation are defects of the Fontan and Glenn procedure. Studying the hemodynamic effect of APBF is beneficial for clinical decisions. This study aimed to explore the effect on particle washout, as well as the differences among the sensitivities of both different hemodynamic parameters and different procedures to APBF.
METHODS
The patient-specific clinical datasets of a patient who underwent bilateral bidirectional Glenn (BBDG) with APBF were enrolled in this study, and using these datasets, Glenn- and Fontan-type artery models were reconstructed. A series of parameters, including the total caval flow pulsatility index (TCPI), indexed energy loss (iPL), wall shear stress (WSS), systemic arterial oxygen saturation (Sat), particle washout time (WOT), pressure in the right superior vena cava (P), pulmonary flow distribution (PFD) and hepatic flow distribution (HFD), were computed from computational fluid dynamic (CFD) simulation to evaluate the hemodynamic effect of APBF.
RESULTS
The result showed that APBF led to better iPL and Sat but worse P and heart load accompanied by a great impact on HFD, making hepatic flow easier to perfuse the side without MPA and APBF. The increase in the APBF rate also effectively results in larger flow pulsation, region velocity, and wall shear stress and lower WOT, and this effect may be more effective for patients with persistent left superior vena cava (PLSVC). However, APBF might have little effect on PFD. Furthermore, APBF might affect WOT, iPL and HFD more significantly than P and has a greater improvement effect in patients with poorer iPL and WOT.
CONCLUSIONS
Moderate APBF is not only a measure to promote pulmonary artery growth and systemic arterial oxygen saturation but also an effective method against endothelial dysfunction and thrombosis. However, moderate APBF is patient-specific and should be determined based on hemodynamic preference that leads to desired patient outcomes, and care should be taken to prevent P and heart load from being too high as well as an imbalance in HFD.
Topics: Fontan Procedure; Heart Defects, Congenital; Hemodynamics; Humans; Pulmonary Artery; Pulmonary Circulation; Retrospective Studies; Time Factors; Treatment Outcome
PubMed: 32072439
DOI: 10.1007/s13239-020-00459-x -
Scientific Reports Apr 2023Chronic thromboembolic pulmonary hypertension is caused by incomplete resolution and organization of thrombi. Blood flow dynamics are involved in thrombus formation;...
Chronic thromboembolic pulmonary hypertension is caused by incomplete resolution and organization of thrombi. Blood flow dynamics are involved in thrombus formation; however, only a few studies have reported on pulmonary artery blood flow dynamics in patients with chronic thromboembolic pulmonary hypertension. Furthermore, the effects of treatment interventions on pulmonary artery blood flow dynamics are not fully understood. The aim of the study was to evaluate pulmonary artery blood flow dynamics in patients with chronic thromboembolic pulmonary hypertension before and after pulmonary endarterectomy and balloon pulmonary angioplasty, using computational fluid dynamics. We analyzed patient-specific pulmonary artery models of 10 patients with chronic thromboembolic pulmonary hypertension and three controls using computational fluid dynamics. In patients with chronic thromboembolic pulmonary hypertension, flow velocity and wall shear stress in the pulmonary arteries were significantly decreased, and the oscillatory shear index and blood stagnation volume were significantly increased than in controls. Pulmonary endarterectomy induced redistribution of pulmonary blood flow and improved blood flow dynamics in the pulmonary artery. Balloon pulmonary angioplasty improved pulmonary blood flow disturbance, decreased blood flow stagnation, and increased wall shear stress, leading to vasodilatation of the distal portion of the pulmonary artery following balloon pulmonary angioplasty treatment.
Topics: Humans; Pulmonary Artery; Pulmonary Embolism; Hypertension, Pulmonary; Pulmonary Circulation; Endarterectomy; Thrombosis; Chronic Disease
PubMed: 37081116
DOI: 10.1038/s41598-023-33727-6 -
The European Respiratory Journal Aug 2021https://bit.ly/3e2GajO
https://bit.ly/3e2GajO
Topics: Bronchi; COVID-19; Humans; Pulmonary Circulation; Respiratory Insufficiency; SARS-CoV-2
PubMed: 33863743
DOI: 10.1183/13993003.04397-2020 -
American Journal of Physiology. Heart... Feb 2021Exercise-induced mitral regurgitation (Ex-MR) is one of the mechanisms that contribute to reduced functional capacity in heart failure (HF). Its prevalence is not well... (Observational Study)
Observational Study
Exercise-induced mitral regurgitation (Ex-MR) is one of the mechanisms that contribute to reduced functional capacity in heart failure (HF). Its prevalence is not well defined across different HF subtypes. The aim of the present study was to describe functional phenotypes and cardiac response to exercise in HFrEF, HFmrEF, and HFpEF, according to Ex-MR prevalence. A total of 218 patients with HF [146 men, 68 (59-78) yr], 137 HFrEF, 41 HFmrEF, 40 HFpEF, and 23 controls were tested with cardiopulmonary exercise test combined with exercise echocardiography. Ex-MR was defined as development of at least moderate (≥2+/4+) regurgitation during exercise. Ex-MR was highly prevalent in the overall population (52%) although differed in the subgroups as follows: 82/137 (60%) in HFrEF, 17/41 (41%) in HFmrEF, and 14/40 (35%) in HFpEF ( < 0.05). Ex-MR was associated with a high rate of ventilation (VE) to carbon dioxide production (VCO) in all HF subtypes [31.2 (26.6-35.6) vs. 33.4 (29.6-40.5), = 0.004; 28.1 (24.5-31.9) vs. 34.4 (28.2-36.7), = 0.01; 28.8 (26.6-32.4) vs. 32.2 (29.2-36.7), = 0.01] and with lower peak VO in HFrEF and HFmrEF. Exercise right ventricle to pulmonary circulation (RV-PC) uncoupling was observed in HFrEF and HFpEF patients with Ex-MR [peak TAPSE/SPAP: HFrEF 0.40 (0.30-0.57) vs. 0.29 (0.23-0.39), = 0.006; HFpEF 0.44 (0.28-0.62) vs. 0.31 (0.27-0.33), = 0.05]. HFpEF with Ex-MR showed a distinct phenotype characterized by better chronotropic reserve and peripheral O extraction. Ex-MR is a common mechanism across the spectrum of HF subtypes and combines with ventilatory inefficiency and RV-PC uncoupling. Interestingly, in HFpEF, Ex-MR emerged as unexpectedly prevalent and peculiarly associated with increased chronotropic response and peripheral O extraction as potential adaptive mechanisms to backward flow redistribution.
Topics: Aged; Echocardiography, Doppler, Color; Echocardiography, Stress; Exercise; Exercise Test; Female; Heart Failure; Hemodynamics; Humans; Italy; Male; Middle Aged; Mitral Valve; Mitral Valve Insufficiency; Phenotype; Prevalence; Prospective Studies; Pulmonary Circulation; Risk Factors; Ventricular Function, Right
PubMed: 33306448
DOI: 10.1152/ajpheart.00507.2020 -
Journal of the American Heart... Feb 2022Background The COVID-19-related pulmonary effects may negatively impact pulmonary hemodynamics and right ventricular function. We examined the prognostic relevance of...
Background The COVID-19-related pulmonary effects may negatively impact pulmonary hemodynamics and right ventricular function. We examined the prognostic relevance of right ventricular function and right ventricular-to-pulmonary circulation coupling assessed by bedside echocardiography in patients hospitalized with COVID-19 pneumonia and a large spectrum of disease independently of indices of pneumonia severity and left ventricular function. Methods and Results Consecutive COVID-19 subjects who underwent full cardiac echocardiographic evaluation along with gas analyses and computed tomography scans were included in the study. Measurements were performed offline, and quantitative analyses were obtained by an operator blinded to the clinical data. We analyzed 133 patients (mean age 69±12 years, 57% men). During a mean hospital stay of 26±16 days, 35 patients (26%) died. The mean tricuspid annular plane systolic excursion/pulmonary artery systolic pressure (TAPSE/PASP) ratio was 0.48±0.18 mm/Hg in nonsurvivors and 0.72±0.32 mm/Hg in survivors (=0.002). For each 0.1 mm/mm Hg increase in TAPSE/PASP, there was a 27% lower risk of in-hospital death (hazard ratio [HR], 0.73 [95% CI, 0.59-0.89]; =0.003). At multivariable analysis, TAPSE/PASP ratio remained a predictor of in-hospital death after adjustments for age, oxygen partial pressure at arterial gas analysis/fraction of inspired oxygen, left ventricular ejection fraction, and computed tomography lung score. Receiver operating characteristic analysis was used to identify the cutoff value of the TAPSE/PASP ratio, which best specified high-risk from lower-risk patients. The best cutoff for predicting in-hospital mortality was TAPSE/PASP <0.57 mm/mm Hg (75% sensitivity and 70% specificity) and was associated with a >4-fold increased risk of in-hospital death (HR, 4.8 [95% CI, 1.7-13.1]; =0.007). Conclusions In patients hospitalized with COVID-19 pneumonia, the assessment of right ventricular to pulmonary circulation coupling appears central to disease evolution and prediction of events. TAPSE/PASP ratio plays a mainstay role as prognostic determinant beyond markers of lung injury.
Topics: Aged; Aged, 80 and over; COVID-19; Echocardiography, Doppler; Female; Hospital Mortality; Humans; Male; Middle Aged; Prognosis; Pulmonary Circulation; Ventricular Dysfunction, Right
PubMed: 35156389
DOI: 10.1161/JAHA.121.023220 -
Hypertension (Dallas, Tex. : 1979) Nov 2023Hypoxic pulmonary hypertension is a difficult disease to manage that is characterized by sustained elevation of pulmonary vascular resistance and pulmonary artery...
BACKGROUND
Hypoxic pulmonary hypertension is a difficult disease to manage that is characterized by sustained elevation of pulmonary vascular resistance and pulmonary artery pressure due to vasoconstriction, perivascular inflammation, and vascular remodeling. Consumption of soluble-fiber is associated with lower systemic blood pressure, but little is known about its ability to affect the pulmonary circulation.
METHODS
Mice were fed either a low- or high-soluble-fiber diet (0% or 16.9% inulin) and then exposed to hypoxia (FiO, 0.10) for 21 days to induce pulmonary hypertension. The impact of diet on right ventricular systolic pressure and pulmonary vascular resistance was determined in vivo or in ex vivo isolated lungs, respectively, and correlated with alterations in the composition of the gut microbiome, plasma metabolome, pulmonary inflammatory cell phenotype, and lung proteome.
RESULTS
High-soluble-fiber diet increased the abundance of short-chain fatty acid-producing bacteria, with parallel increases in plasma propionate levels, and reduced the abundance of disease-related bacterial genera such as , , and in hypoxic mice with parallel decreases in plasma levels of p-cresol sulfate. High-soluble-fiber diet decreased hypoxia-induced elevations of right ventricular systolic pressure and pulmonary vascular resistance. These changes were associated with reduced proportions of interstitial macrophages, dendritic cells, and nonclassical monocytes. Whole-lung proteomics revealed proteins and molecular pathways that may explain the effect of soluble-fiber supplementation.
CONCLUSIONS
This study demonstrates for the first time that a high-soluble-fiber diet attenuates hypoxia-induced pulmonary vascular remodeling and the development of pulmonary hypertension in a mouse model of hypoxic pulmonary hypertension and highlights diet-derived metabolites that may have an immuno-modulatory role in the lung.
Topics: Mice; Animals; Hypertension, Pulmonary; Vascular Remodeling; Lung; Pulmonary Circulation; Hypoxia; Pulmonary Artery
PubMed: 37851762
DOI: 10.1161/HYPERTENSIONAHA.123.20914 -
European Journal of Heart Failure Apr 2024Pulmonary hypertension (PH) associated with left heart failure (LHF) (PH-LHF) is one of the most common causes of PH. It directly contributes to symptoms and reduced... (Review)
Review
A roadmap for therapeutic discovery in pulmonary hypertension associated with left heart failure. A scientific statement of the Heart Failure Association (HFA) of the ESC and the ESC Working Group on Pulmonary Circulation & Right Ventricular Function.
Pulmonary hypertension (PH) associated with left heart failure (LHF) (PH-LHF) is one of the most common causes of PH. It directly contributes to symptoms and reduced functional capacity and negatively affects right heart function, ultimately leading to a poor prognosis. There are no specific treatments for PH-LHF, despite the high number of drugs tested so far. This scientific document addresses the main knowledge gaps in PH-LHF with emphasis on pathophysiology and clinical trials. Key identified issues include better understanding of the role of pulmonary venous versus arteriolar remodelling, multidimensional phenotyping to recognize patient subgroups positioned to respond to different therapies, and conduct of rigorous pre-clinical studies combining small and large animal models. Advancements in these areas are expected to better inform the design of clinical trials and extend treatment options beyond those effective in pulmonary arterial hypertension. Enrichment strategies, endpoint assessments, and thorough haemodynamic studies, both at rest and during exercise, are proposed to play primary roles to optimize early-stage development of candidate therapies for PH-LHF.
Topics: Humans; Heart Failure; Hypertension, Pulmonary; Ventricular Function, Right; Pulmonary Circulation
PubMed: 38639017
DOI: 10.1002/ejhf.3236 -
Seminars in Thoracic and Cardiovascular... 2021Hypoplastic left heart complex with "borderline left ventricle" and intact ventricular septum is a clinical conundrum for the congenital heart surgeon. The choice... (Review)
Review
Hypoplastic left heart complex with "borderline left ventricle" and intact ventricular septum is a clinical conundrum for the congenital heart surgeon. The choice between neonatal biventricular repair and single ventricle palliation can be challenging, and the current tools to aid in the decision-making process fail to account for the morbidity associated with intermediate and late diastolic dysfunction. Staged ventricular recruitment, consisting of valvular repair techniques, resection of endocardial fibroelastosis, atrial septal restriction, and augmentation of pulmonary blood flow, has been shown to improve left ventricular size and function culminating in eventual biventricular circulation. Despite staged ventricular recruitment, some patients cannot undergo biventricular conversion. Strategies to address these complex patients, including the "reverse" double switch, are the next frontier in biventricular repair.
Topics: Endocardial Fibroelastosis; Heart Ventricles; Humans; Hypoplastic Left Heart Syndrome; Infant, Newborn; Palliative Care; Pulmonary Circulation
PubMed: 34116780
DOI: 10.1053/j.pcsu.2021.03.001 -
Biomolecules Nov 2021Potassium ion concentrations, controlled by ion pumps and potassium channels, predominantly govern a cell's membrane potential and the tone in the vessels.... (Review)
Review
Potassium ion concentrations, controlled by ion pumps and potassium channels, predominantly govern a cell's membrane potential and the tone in the vessels. Calcium-activated potassium channels respond to two different stimuli-changes in voltage and/or changes in intracellular free calcium. Large conductance calcium-activated potassium (BKCa) channels assemble from pore forming and various modulatory and auxiliary subunits. They are of vital significance due to their very high unitary conductance and hence their ability to rapidly cause extreme changes in the membrane potential. The pathophysiology of lung diseases in general and pulmonary hypertension, in particular, show the implication of either decreased expression and partial inactivation of BKCa channel and its subunits or mutations in the genes encoding different subunits of the channel. Signaling molecules, circulating humoral molecules, vasorelaxant agents, etc., have an influence on the open probability of the channel in pulmonary arterial vascular cells. BKCa channel is a possible therapeutic target, aimed to cause vasodilation in constricted or chronically stiffened vessels, as shown in various animal models. This review is a comprehensive collation of studies on BKCa channels in the pulmonary circulation under hypoxia (hypoxic pulmonary vasoconstriction; HPV), lung pathology, and fetal to neonatal transition, emphasising pharmacological interventions as viable therapeutic options.
Topics: Calcium; Large-Conductance Calcium-Activated Potassium Channels; Pulmonary Circulation
PubMed: 34827626
DOI: 10.3390/biom11111629 -
Pediatric Radiology Jul 2022The ductus arteriosus is important to fetal circulation. Failure to close at birth is a common event. In this educational pictorial essay, we illustrate the association...
The ductus arteriosus is important to fetal circulation. Failure to close at birth is a common event. In this educational pictorial essay, we illustrate the association of the ductus arteriosus with a variety of congenital cardiac, vascular and pulmonary lesions. These lesions can impact the systemic circulation, the pulmonary circulation or the airway and include coarctation of the aorta, ductal origin of the pulmonary artery and vascular rings.
Topics: Ductus Arteriosus; Ductus Arteriosus, Patent; Heart; Humans; Infant, Newborn; Pulmonary Artery; Pulmonary Circulation
PubMed: 35809133
DOI: 10.1007/s00247-022-05387-7