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Echocardiography (Mount Kisco, N.Y.) Aug 2017The right heart pulmonary circulation unit (RH-PCU) is a key determinant of prognosis in several cardiorespiratory diseases. Although right heart catheterization is... (Review)
Review
The right heart pulmonary circulation unit (RH-PCU) is a key determinant of prognosis in several cardiorespiratory diseases. Although right heart catheterization is considered the gold standard for pulmonary hemodynamic assessment, a comprehensive cardiovascular ultrasound approach is an essential step in the diagnostic-prognostic clinical pathway of patients with suspect or overt pulmonary hypertension. The exponential development of advanced ultrasound techniques (strain, 3-dimensional echocardiography and lung ultrasound) has led to new insights into the evaluation of RH-PCU structure and function, overcoming some limitations of standard Doppler echocardiography. In the near future, exercise Doppler echocardiography may become a useful technique for detecting a latent stage of pulmonary hypertension and for evaluating right ventricular contractile reserve.
Topics: Echocardiography, Doppler; Echocardiography, Three-Dimensional; Heart Ventricles; Humans; Hypertension, Pulmonary; Pulmonary Circulation; Ventricular Function, Right
PubMed: 28664665
DOI: 10.1111/echo.13594 -
European Heart Journal Nov 2022
Topics: Humans; Pulmonary Circulation; Pulmonary Edema; Lung; Hemodynamics
PubMed: 36104502
DOI: 10.1093/eurheartj/ehac499 -
Journal of Echocardiography Mar 2023Pulmonary transit time (PTT) and pulmonary blood volume (PBV) derived from non-invasive imaging correlate with pulmonary artery wedge pressure. The response of PBV to...
BACKGROUND
Pulmonary transit time (PTT) and pulmonary blood volume (PBV) derived from non-invasive imaging correlate with pulmonary artery wedge pressure. The response of PBV to exercise may be useful in the evaluation of cardiopulmonary disease but whether PBV can be obtained reliably following exercise is unknown. We therefore aimed to assess the technical feasibility of measuring PTT and PBV after exercise using contrast echocardiography.
METHODS
In healthy volunteers, PTT was calculated from time-intensity curves generated as contrast traversed the cardiac chambers before and immediately after participants performed sub-maximal exercise on the Standard Bruce Protocol. From the product of PTT and heart rate (HR) during contrast passage through the pulmonary circulation, PBV relative to systemic stroke volume (rPBV) was calculated.
RESULTS
The cohort consisted of 14 individuals (age: 46 ± 8 years; 2 female) without cardiopulmonary disease. Exercise time was 8 ¾ ± 1 ¾ minutes and participants reached 85 ± 9% of age-predicted maximal HR, which corresponded to a near-doubling of resting HR at the time of post-exercise contrast injection. Data sufficient to derive PTT and rPBV were obtained for all participants. With exercise, the change in PBV from baseline ranged from 56 to 138% of systemic stroke volume, consistent with rPBV and absolute PBV values obtained in prior studies.
CONCLUSIONS
Acquisition of PTT and rPBV using contrast echocardiography after exercise is achievable and the results are physiologically plausible. As the next step towards clinical implementation, validation of this technique against hemodynamic exercise studies appears reasonable.
Topics: Humans; Female; Adult; Middle Aged; Blood Volume; Pulmonary Circulation; Echocardiography; Pulmonary Wedge Pressure; Heart
PubMed: 35829996
DOI: 10.1007/s12574-022-00582-9 -
Progress in Cardiovascular Diseases 2016Pulmonary hypertension (PH) is common in patients with heart failure with preserved ejection fraction (HFpEF). While PH-HFpEF may affect more than a million patients in... (Review)
Review
Pulmonary hypertension (PH) is common in patients with heart failure with preserved ejection fraction (HFpEF). While PH-HFpEF may affect more than a million patients in the United States alone, it has been difficult to study its epidemiology and response to treatment due to difficulty in properly defining the illness. While chronic remodeling of the pulmonary vasculature is related to chronic passive congestion of the pulmonary circulation from the pulmonary veins, there are likely other contributors to the development of PH-HFpEF. We explore the potential direct contributions of obesity, diabetes mellitus, genetics, and sleep apnea on the pulmonary circulation in those with PH-HFpEF, and we discuss the potential role of exercise testing or fluid challenge during diagnostic testing.
Topics: Diagnostic Imaging; Disease Progression; Heart Failure; Humans; Hypertension, Pulmonary; Pulmonary Circulation; Stroke Volume
PubMed: 27350563
DOI: 10.1016/j.pcad.2016.06.002 -
Echocardiography (Mount Kisco, N.Y.) Jan 2015Echocardiography is a key screening tool in the diagnostic algorithm of pulmonary arterial hypertension (PAH). It provides an estimate of right ventricular function and... (Review)
Review
Echocardiography is a key screening tool in the diagnostic algorithm of pulmonary arterial hypertension (PAH). It provides an estimate of right ventricular function and pulmonary artery pressure, either at rest or during exercise, and is useful in ruling out secondary causes of pulmonary hypertension (PH) such as left heart disease or congenital heart disease. Several studies have showed that echocardiography is insufficiently precise as single tool for the ultimate diagnosis of PH respect to the right heart catheterization, considered the gold standard technique. Echocardiography is valuable in assessing prognosis and treatment options, monitoring the efficacy of specific therapeutic interventions, and detecting the preclinical stages of disease. The ideal imaging modality for accurate noninvasive assessment of the right heart should be accurate and precise, not influenced by loading conditions, routinely practicable and easily repeatable. For all such reasons and considering that PAH is a rare and severe condition, a complete noninvasive assessment of right heart function requires a deep knowledge of the disease and a multimodality approach.
Topics: Cardiac Catheterization; Echocardiography, Three-Dimensional; Female; Humans; Hypertension, Pulmonary; Male; Mass Screening; Monitoring, Physiologic; Prognosis; Pulmonary Circulation; Pulmonary Wedge Pressure; Sensitivity and Specificity; Severity of Illness Index; Ventricular Dysfunction, Right; Ventricular Function, Right
PubMed: 25244441
DOI: 10.1111/echo.12283 -
Heart Failure Clinics Jan 2023Main pulmonary vascular diseases (PVD) with precapillary pulmonary hypertension (PH) are pulmonary arterial and chronic thromboembolic PH. Guidelines recommend... (Meta-Analysis)
Meta-Analysis Review
Main pulmonary vascular diseases (PVD) with precapillary pulmonary hypertension (PH) are pulmonary arterial and chronic thromboembolic PH. Guidelines recommend supplemental oxygen therapy (SOT) for severely hypoxemic patients with PH, but evidence is scarce. The authors performed a systematic review and where possible meta-analyses on the effects of SOT on hemodynamics and exercise performance in patients with PVD. In PVD, short-term SOT significantly improved mean pulmonary artery pressure and exercise performance. There is growing evidence on the benefit of long-term SOT for selected patients with PVD regarding exercise capacity and maybe even survival.
Topics: Humans; Pulmonary Circulation; Vascular Diseases; Hypertension, Pulmonary; Pulmonary Artery; Hemodynamics; Oxygen
PubMed: 36922056
DOI: 10.1016/j.hfc.2022.11.001 -
Cardiology in the Young Nov 2023The objective was to study the ductus arteriosus morphology in duct-dependent pulmonary circulation and its pattern in different ventricle morphology using CT...
BACKGROUND
The objective was to study the ductus arteriosus morphology in duct-dependent pulmonary circulation and its pattern in different ventricle morphology using CT angiography.
METHOD
From January 2013 to December 2015, patients aged 6 months and below with duct-dependent pulmonary circulation underwent CT angiography to delineate the ductus arteriosus origin, tortuosity, site of insertion, and pulmonary artery anatomy. The ductus arteriosus were classified into type I, IIa, IIb, and III based on its site of origin, either from descending aorta, distal arch, proximal arch, or subclavian artery, respectively.
RESULTS
A total of 114 patients and 116 ductus arteriosus (two had bilateral ductus arteriosus) were analysed. Type I, IIa, IIb, and III ductus arteriosus were seen in 13 (11.2 %), 71 (61.2%), 21 (18.1%), and 11 (9.5%), respectively. Tortuous ductus arteriosus was found in 38 (32.7%), which was commonly seen in single ventricular lesions. Ipsilateral and bilateral branch pulmonary artery stenosis was seen in 68 (59.6%) and 6 (5.3%) patients, respectively. The majority of patients with pulmonary atresia intact ventricular septum had type I (54.4%) and non-tortuous ductus arteriosus, while those with single and biventricular lesions had type II ductus arteriosus (84.9% and 89.7%, respectively). Type III ductus arteriosus was more common in biventricular lesions (77.8%).
CONCLUSIONS
Ductus arteriosus in duct-dependent pulmonary circulation has a diverse morphology with a distinct origin and tortuosity pattern in different types of ventricular morphology. CT may serve as an important tool in case selection and pre-procedural planning for ductal stenting.
Topics: Humans; Ductus Arteriosus; Pulmonary Circulation; Ductus Arteriosus, Patent; Pulmonary Atresia; Stents; Computed Tomography Angiography
PubMed: 36651340
DOI: 10.1017/S1047951122004218 -
International Journal of Cardiology Nov 2018Elevation in central venous pressure (CVP) plays a fundamental pathophysiologic role in Fontan circulation. Because there is no sub-pulmonary ventricle in this system,...
BACKGROUND
Elevation in central venous pressure (CVP) plays a fundamental pathophysiologic role in Fontan circulation. Because there is no sub-pulmonary ventricle in this system, CVP also provides the driving force for pulmonary blood flow. We hypothesized that this would make Fontan patients more susceptible to even low-level elevation in pulmonary vascular resistance index (PVRI), resulting in greater systemic venous congestion and adverse outcomes.
METHODS
Adult Fontan patients and controls without congenital heart disease undergoing clinical evaluation that included cardiac catheterization and echocardiography were examined retrospectively. Outcomes including all-cause mortality and the development of Fontan associated diseases (FAD, defined as protein losing enteropathy, cirrhosis, heart failure hospitalization, arrhythmia, or thromboembolism) were assessed from longitudinal assessment.
RESULTS
As compared to controls (n = 82), Fontan patients (n = 164) were younger (36 vs 45 years, p < 0.001), more likely to be on anticoagulation or antiplatelet therapy, and more likely to have atrial arrhythmia or cirrhosis. There was a strong correlation between CVP and PVRI in the Fontan group (r = 0.79, p < 0.001), but there was no such relationship in controls. Elevated PVRI identified patients at increased risk for FAD (HR 1.92, 95% CI 1.39-2.41, p = 0.01), and composite endpoint of FAD and/or death (HR 1.89, 95% CI 1.32-2.53, p = 0.01) per 1 WU∗m increment.
CONCLUSIONS
Systemic venous congestion, which is the primary factor in the pathogenesis of FAD and death, is related to even low-level abnormalities in pulmonary vascular function. Multicenter studies are needed to determine whether interventions targeting pulmonary vascular structure and function can improve outcomes in the Fontan population.
Topics: Adult; Central Venous Pressure; Cohort Studies; Cross-Sectional Studies; Female; Fontan Procedure; Humans; Hyperemia; Male; Middle Aged; Prognosis; Pulmonary Circulation; Retrospective Studies; Treatment Outcome
PubMed: 30223363
DOI: 10.1016/j.ijcard.2018.05.039 -
Journal of Clinical Monitoring and... Dec 2018We have previously developed a simulated cardiovascular physiology model for in-silico testing and validation of novel closed-loop controllers. To date, a detailed model...
We have previously developed a simulated cardiovascular physiology model for in-silico testing and validation of novel closed-loop controllers. To date, a detailed model of the right heart and pulmonary circulation was not needed, as previous controllers were not intended for use in patients with cardiac or pulmonary pathology. With new development of controllers for vasopressors, and looking forward, for combined vasopressor-fluid controllers, modeling of right-sided and pulmonary pathology is now relevant to further in-silico validation, so we aimed to expand our existing simulation platform to include these elements. Our hypothesis was that the completed platform could be tuned and stabilized such that the distributions of a randomized sample of simulated patients' baseline characteristics would be similar to reported population values. Our secondary outcomes were to further test the system in representing acute right heart failure and pulmonary artery hypertension. After development and tuning of the right-sided circulation, the model was validated against clinical data from multiple previously published articles. The model was considered 'tuned' when 100% of generated randomized patients converged to stability (steady, physiologically-plausible compartmental volumes, flows, and pressures) and 'valid' when the means for the model data in each health condition were contained within the standard deviations for the published data for the condition. A fully described right heart and pulmonary circulation model including non-linear pressure/volume relationships and pressure dependent flows was created over a 6-month span. The model was successfully tuned such that 100% of simulated patients converged into a steady state within 30 s. Simulation results in the healthy state for central venous volume (3350 ± 132 ml) pulmonary blood volume (405 ± 39 ml), pulmonary artery pressures (systolic 20.8 ± 4.1 mmHg and diastolic 9.4 ± 1.8 mmHg), left atrial pressure (4.6 ± 0.8 mmHg), PVR (1.0 ± 0.2 wood units), and CI (3.8 ± 0.5 l/min/m) all met criteria for acceptance of the model, though the standard deviations of LAP and CI were somewhat narrower than published comparators. The simulation results for right ventricular infarction also fell within the published ranges: pulmonary blood volume (727 ± 102 ml), pulmonary arterial pressures (30 ± 4 mmHg systolic, 12 ± 2 mmHg diastolic), left atrial pressure (13 ± 2 mmHg), PVR (1.6 ± 0.3 wood units), and CI (2.0 ± 0.4 l/min/m) all fell within one standard deviation of the reported population values and vice-versa. In the pulmonary hypertension model, pulmonary blood volume of 615 ± 90 ml, pulmonary arterial pressures of 80 ± 14 mmHg systolic, 36 ± 7 mmHg diastolic, and the left atrial pressure of 11 ± 2 mmHg all met criteria for acceptance. For CI, the simulated value of 2.8 ± 0.4 l/min/m once again had a narrower spread than most of the published data, but fell inside of the SD of all published data, and the PVR value of 7.5 ± 1.6 wood units fell in the middle of the four published studies. The right-ventricular and pulmonary circulation simulation appears to be a reasonable approximation of the right-sided circulation for healthy physiology as well as the pathologic conditions tested.
Topics: Computer Simulation; Fluid Therapy; Heart Failure; Heart Ventricles; Humans; Hypertension, Pulmonary; Models, Cardiovascular; Pulmonary Circulation; Ventricular Dysfunction, Right; Ventricular Function
PubMed: 29330837
DOI: 10.1007/s10877-018-0099-2 -
Reproductive Sciences (Thousand Oaks,... Mar 2019Sildenafil is a potential new treatment for placental insufficiency in human pregnancies as it reduces the breakdown of vasodilator nitric oxide. Pulmonary...
Sildenafil is a potential new treatment for placental insufficiency in human pregnancies as it reduces the breakdown of vasodilator nitric oxide. Pulmonary vasodilatation is observed in normoxemic fetuses following sildenafil administration. Placental insufficiency often leads to fetal hypoxemia that can cause pulmonary vasoconstriction and fetal cardiac dysfunction as evidenced by reduced isovolumic myocardial velocities. We tested the hypotheses that sildenafil, when given directly to the hypoxemic fetus, reverses reactive pulmonary vasoconstriction, increases left ventricular cardiac output by increasing pulmonary venous return, and ameliorates hypoxemic myocardial dysfunction. We used an instrumented sheep model. Fetuses were made hypoxemic over a mean (standard deviation) duration of 41.3 (9.5) minutes and then given intravenous sildenafil or saline infusion. Volume blood flow through ductus arteriosus was measured with an ultrasonic transit-time flow probe. Fetal left and right ventricular outputs and lung volume blood flow were calculated, and ventricular function was examined using echocardiography. Lung volume blood flow decreased and the ductus arteriosus volume blood flow increased with hypoxemia. There was a significant reduction in left ventricular and combined cardiac outputs during hypoxemia in both groups. Hypoxemia led to a reduction in myocardial isovolumic velocities, increased ductus venosus pulsatility, and reduced left ventricular myocardial deformation. Direct administration of sildenafil to hypoxemic fetus did not reverse the redistribution of cardiac output. Furthermore, fetal cardiac systolic and diastolic dysfunction was observed during hypoxemia, which was not improved by fetal sildenafil treatment. In conclusion, sildenafil did not improve pulmonary blood flow or cardiac function in hypoxemic sheep fetuses.
Topics: Animals; Cardiac Output; Disease Models, Animal; Female; Hemodynamics; Hypoxia; Placental Insufficiency; Pregnancy; Pulmonary Circulation; Sheep; Sildenafil Citrate; Vasodilator Agents
PubMed: 29716434
DOI: 10.1177/1933719118773412